Gene expression in thiazide diuretic or statin users in relation to incident type 2 diabetes.

PubMed

Suchy-Dicey, Astrid; Heckbert, Susan R; Smith, Nicholas L; McKnight, Barbara; Rotter, Jerome I; Chen, Yd Ida; Psaty, Bruce M; Enquobahrie, Daniel A

2014-01-01

Thiazide diuretics and statins are used to improve cardiovascular outcomes, but may also cause type 2 diabetes (T2DM), although mechanisms are unknown. Gene expression studies may facilitate understanding of these associations. Participants from ongoing population-based studies were sampled for these longitudinal studies of peripheral blood microarray gene expression, and followed to incident diabetes. All sampled subjects were statin or thiazide users. Those who developed diabetes during follow-up comprised cases (44 thiazide users; 19 statin users), and were matched to drug-using controls who did not develop diabetes on several factors. Supervised normalization, surrogate variable analyses removed technical bias and confounding. Differentially-expressed genes were those with a false discovery rate Q-value<0.05. Among thiazide users, diabetes cases had significantly different expression of CCL14 (down-regulated 6%, Q-value=0.0257), compared with controls. Among statin users, diabetes cases had marginal but insignificantly different expression of ZNF532 (up-regulated 15%, Q-value=0.0584), CXORF21 (up-regulated 11%, Q-value=0.0584), and ZNHIT3 (up-regulated 19%, Q-value=0.0959), compared with controls. These genes comprise potential targets for future expression or mechanistic research on medication-related diabetes development.

A randomised controlled trial for the evaluation of risk for type 2 diabetes in hypertensive patients receiving thiazide diuretics: Diuretics In the Management of Essential hypertension (DIME) study

PubMed Central

Ueda, Shinichiro; Morimoto, Takeshi; Ando, Shin-ichi; Takishita, Shu-ichi; Kawano, Yuhei; Shimamoto, Kazuaki; Ogihara, Toshio; Saruta, Takao

2014-01-01

Objectives Thiazide diuretics are one of the first choice antihypertensives but not optimally utilised because of concerns regarding their adverse effects on glucose metabolism. The Diuretics In the Management of Essential hypertension (DIME) study was designed, for the first time, to assess the risk for type 2 diabetes mellitus in patients with essential hypertension during antihypertensive treatment with low-dose thiazide diuretics compared to those not treated with diuretics. Design Multicentre, unblinded, pragmatic, randomised, controlled trial with blinded assessment of end points and intention-to-treat analysis that was started in 2004 and finished in 2012. Setting Hypertension clinics at 106 sites in Japan, including general practitioners’ offices and teaching hospitals. Participants Non-diabetic patients with essential hypertension. Interventions Antihypertensive treatment with low-dose thiazide diuretics at 12.5 mg/day of hydrochlorothiazide or equivalent (Diuretics group) or that without thiazide diuretics (No-diuretics group). Main outcome The primary outcome was new onset of type 2 diabetes diagnosed according to WHO criteria and the criteria of Japanese Society of Diabetes. Results 1130 patients were allocated to Diuretics (n=544) or No-diuretics group (n=586). Complete end point information was collected for 1049 participants after a median follow-up of 4.4 years. Diabetes developed in 25 (4.6%) participants in the Diuretics group, as compared with 29 (4.9%) in the No-diuretics group (HR 0.93; 95% CI 0.55 to 1.58; p=0.800). Conclusions Antihypertensive treatment with thiazide diuretics at low doses may not be associated with an increased risk for new onset of type 2 diabetes. This result might suggest safety of use of low doses of thiazide diuretics. Trial registration number ClinicalTrials.gov NCT00131846. PMID:25031188

Acetazolamide Attenuates Lithium–Induced Nephrogenic Diabetes Insipidus

PubMed Central

de Groot, Theun; Sinke, Anne P.; Kortenoeven, Marleen L.A.; Alsady, Mohammad; Baumgarten, Ruben; Devuyst, Olivier; Loffing, Johannes; Wetzels, Jack F.

2016-01-01

To reduce lithium–induced nephrogenic diabetes insipidus (lithium-NDI), patients with bipolar disorder are treated with thiazide and amiloride, which are thought to induce antidiuresis by a compensatory increase in prourine uptake in proximal tubules. However, thiazides induced antidiuresis and alkalinized the urine in lithium-NDI mice lacking the sodium-chloride cotransporter, suggesting that inhibition of carbonic anhydrases (CAs) confers the beneficial thiazide effect. Therefore, we tested the effect of the CA–specific blocker acetazolamide in lithium-NDI. In collecting duct (mpkCCD) cells, acetazolamide reduced the cellular lithium content and attenuated lithium-induced downregulation of aquaporin-2 through a mechanism different from that of amiloride. Treatment of lithium-NDI mice with acetazolamide or thiazide/amiloride induced similar antidiuresis and increased urine osmolality and aquaporin-2 abundance. Thiazide/amiloride-treated mice showed hyponatremia, hyperkalemia, hypercalcemia, metabolic acidosis, and increased serum lithium concentrations, adverse effects previously observed in patients but not in acetazolamide-treated mice in this study. Furthermore, acetazolamide treatment reduced inulin clearance and cortical expression of sodium/hydrogen exchanger 3 and attenuated the increased expression of urinary PGE2 observed in lithium-NDI mice. These results show that the antidiuresis with acetazolamide was partially caused by a tubular-glomerular feedback response and reduced GFR. The tubular-glomerular feedback response and/or direct effect on collecting duct principal or intercalated cells may underlie the reduced urinary PGE2 levels with acetazolamide, thereby contributing to the attenuation of lithium-NDI. In conclusion, CA activity contributes to lithium-NDI development, and acetazolamide attenuates lithium-NDI development in mice similar to thiazide/amiloride but with fewer adverse effects. PMID:26574046

The non-diuretic hypotensive effects of thiazides are enhanced during volume depletion states

PubMed Central

Alshahrani, Saeed; Rapoport, Robert M.; Zahedi, Kamyar; Jiang, Min; Nieman, Michelle; Barone, Sharon; Meredith, Andrea L.; Lorenz, John N.; Rubinstein, Jack

2017-01-01

Thiazide derivatives including Hydrochlorothiazide (HCTZ) represent the most common treatment of mild to moderate hypertension. Thiazides initially enhance diuresis via inhibition of the kidney Na+-Cl- Cotransporter (NCC). However, chronic volume depletion and diuresis are minimal while lowered blood pressure (BP) is maintained on thiazides. Thus, a vasodilator action of thiazides is proposed, likely via Ca2+-activated K+ (BK) channels in vascular smooth muscles. This study ascertains the role of volume depletion induced by salt restriction or salt wasting in NCC KO mice on the non-diuretic hypotensive action of HCTZ. HCTZ (20mg/kg s.c.) lowered BP in 1) NCC KO on a salt restricted diet but not with normal diet; 2) in volume depleted but not in volume resuscitated pendrin/NCC dKO mice; the BP reduction occurs without any enhancement in salt excretion or reduction in cardiac output. HCTZ still lowered BP following treatment of NCC KO on salt restricted diet with paxilline (8 mg/kg, i.p.), a BK channel blocker, and in BK KO and BK/NCC dKO mice on salt restricted diet. In aortic rings from NCC KO mice on normal and low salt diet, HCTZ did not alter and minimally decreased maximal phenylephrine contraction, respectively, while contractile sensitivity remained unchanged. These results demonstrate 1) the non-diuretic hypotensive effects of thiazides are augmented with volume depletion and 2) that the BP reduction is likely the result of HCTZ inhibition of vasoconstriction through a pathway dependent on factors present in vivo, is unrelated to BK channel activation, and involves processes associated with intravascular volume depletion. PMID:28719636

Gene expression in thiazide diuretic or statin users in relation to incident type 2 diabetes

PubMed Central

Suchy-Dicey, Astrid; Heckbert, Susan R; Smith, Nicholas L; McKnight, Barbara; Rotter, Jerome I; Chen, YD Ida; Psaty, Bruce M; Enquobahrie, Daniel A

2014-01-01

Thiazide diuretics and statins are used to improve cardiovascular outcomes, but may also cause type 2 diabetes (T2DM), although mechanisms are unknown. Gene expression studies may facilitate understanding of these associations. Participants from ongoing population-based studies were sampled for these longitudinal studies of peripheral blood microarray gene expression, and followed to incident diabetes. All sampled subjects were statin or thiazide users. Those who developed diabetes during follow-up comprised cases (44 thiazide users; 19 statin users), and were matched to drug-using controls who did not develop diabetes on several factors. Supervised normalization, surrogate variable analyses removed technical bias and confounding. Differentially-expressed genes were those with a false discovery rate Q-value<0.05. Among thiazide users, diabetes cases had significantly different expression of CCL14 (down-regulated 6%, Q-value=0.0257), compared with controls. Among statin users, diabetes cases had marginal but insignificantly different expression of ZNF532 (up-regulated 15%, Q-value=0.0584), CXORF21 (up-regulated 11%, Q-value=0.0584), and ZNHIT3 (up-regulated 19%, Q-value=0.0959), compared with controls. These genes comprise potential targets for future expression or mechanistic research on medication-related diabetes development. PMID:24596594

Prescription patterns of diuretics in Dutch community-dwelling elderly patients

PubMed Central

Van Kraaij, Dave J W; Jansen, René W M M; De Gier, Johan J; Gribnau, Frank W J; Hoefnagels, Willibrord H L

1998-01-01

Aims To describe age-and gender-related prescription patterns of diuretics in community-dwelling elderly, and to compare diuretics to other cardiovascular (CV) medications. Methods Cross-sectional study of patient-specific prescription data derived from a panel of 10 Dutch community pharmacies. Determination of proportional prescription rates and prescribed daily dose (PDD) of diuretics, cardiac glycosides, nitrates, angiotensin converting enzyme (ACE) inhibitors, β-adrenoceptor blockers, and calcium channel blockers in all 5326 patients aged 65 years or older dispensed CV medications between August 1st, 1995 and February 1st, 1996. Results Diuretics were prescribed to 2677 of 5326 patients (50.3%), 1325 patients (24.9%) using thiazides and 1198 patients (22.5%) using loop diuretics. Prescription rates of loop diuretics increased from 15.1% in patients aged 65–74 years to 37.2% in patients aged 85 years or older. Rates also increased for digoxin and nitrates. Rates for thiazide diuretics remained unchanged with age; rates for β-adrenoceptor blockers, ACE inhibitors and calcium channel blockers declined with age. Thiazides were prescribed to 30.1% of women compared with 16% of men (P<0.001). Average PDD was 135±117% of defined daily dose (DDD) for loop diuretics, and highest for bumetanide (245±2.01% of DDD, equivalent to 2.5±2.0 mg). Average PDD was 74±40% of DDD for thiazides, and highest for chlorthalidone (100±49% of DDD, equivalent to 25±12 mg). Conclusions Important characteristics of diuretic usage patterns in this elderly population were a steep increase in loop diuretic use in the oldest old, a large gender difference for thiazide use, and high prescribed doses for thiazides. PMID:9803990

Acetazolamide Attenuates Lithium-Induced Nephrogenic Diabetes Insipidus.

PubMed

de Groot, Theun; Sinke, Anne P; Kortenoeven, Marleen L A; Alsady, Mohammad; Baumgarten, Ruben; Devuyst, Olivier; Loffing, Johannes; Wetzels, Jack F; Deen, Peter M T

2016-07-01

To reduce lithium-induced nephrogenic diabetes insipidus (lithium-NDI), patients with bipolar disorder are treated with thiazide and amiloride, which are thought to induce antidiuresis by a compensatory increase in prourine uptake in proximal tubules. However, thiazides induced antidiuresis and alkalinized the urine in lithium-NDI mice lacking the sodium-chloride cotransporter, suggesting that inhibition of carbonic anhydrases (CAs) confers the beneficial thiazide effect. Therefore, we tested the effect of the CA-specific blocker acetazolamide in lithium-NDI. In collecting duct (mpkCCD) cells, acetazolamide reduced the cellular lithium content and attenuated lithium-induced downregulation of aquaporin-2 through a mechanism different from that of amiloride. Treatment of lithium-NDI mice with acetazolamide or thiazide/amiloride induced similar antidiuresis and increased urine osmolality and aquaporin-2 abundance. Thiazide/amiloride-treated mice showed hyponatremia, hyperkalemia, hypercalcemia, metabolic acidosis, and increased serum lithium concentrations, adverse effects previously observed in patients but not in acetazolamide-treated mice in this study. Furthermore, acetazolamide treatment reduced inulin clearance and cortical expression of sodium/hydrogen exchanger 3 and attenuated the increased expression of urinary PGE2 observed in lithium-NDI mice. These results show that the antidiuresis with acetazolamide was partially caused by a tubular-glomerular feedback response and reduced GFR. The tubular-glomerular feedback response and/or direct effect on collecting duct principal or intercalated cells may underlie the reduced urinary PGE2 levels with acetazolamide, thereby contributing to the attenuation of lithium-NDI. In conclusion, CA activity contributes to lithium-NDI development, and acetazolamide attenuates lithium-NDI development in mice similar to thiazide/amiloride but with fewer adverse effects. Copyright © 2016 by the American Society of Nephrology.

Antialbuminuric effect of eplerenone in comparison to thiazide diuretics in patients with hypertension.

PubMed

Sawai, Toshiki; Dohi, Kaoru; Fujimoto, Naoki; Okubo, Setsuya; Isaka, Naoki; Ichikawa, Takehiko; Makino, Katsutoshi; Okamoto, Shinya; Koyabu, Sukenari; Kitamura, Tetsuya; Ogura, Toru; Yamada, Tomomi; Tamaru, Satoshi; Nishikawa, Masakatsu; Nakamura, Mashio; Ito, Masaaki

2017-10-01

This study investigated the effects and safety of eplerenone or thiazide diuretics in patients with hypertension and albuminuria (pretreatment urinary albumin/creatinine ratio ≥10 mg/gCr) treated with an angiotensin II receptor blocker. The primary end point was the mean percent change in the urinary albumin/creatinine ratio from baseline to 48 weeks. An efficacy analysis was performed in 195 patients (98 in the eplerenone group and 97 in the thiazide group). Systolic and diastolic blood pressures at 48 weeks were similar in the two groups. The mean percent change in the urinary albumin/creatinine ratio from baseline to 48 weeks was similar in the two groups (P=.804). In the safety analysis, the withdrawal rates for adverse events were similar in both groups. The antialbuminuric effects and safety of eplerenone therapy were similar to those of thiazide diuretics when combined with an angiotensin II receptor blocker in patients with hypertension and albuminuria. ©2017 Wiley Periodicals, Inc.

Evidence-based diuretics: focus on chlorthalidone and indapamide.

PubMed

DiNicolantonio, James J; Bhutani, Jaikrit; Lavie, Carl J; O'Keefe, James H

2015-03-01

Thiazide and thiazide-like diuretics are cornerstone treatments for hypertension. However, unlike chlorthalidone (CTD) and indapamide (IDP), hydrochlorothiazide (HCTZ) lacks evidence for reducing morbidity and mortality as monotherapy compared with placebo or control. Despite this fact, HCTZ is prescribed much more frequently than CTD or IDP. We believe that all hypertension guidelines should follow the National Institute for Health and Excellence (NICE) and make IDP and CTD first choice 'thiazide-like diuretics.' This article will focus on the available evidence pertaining to HCTZ versus CTD and IDP. We will review the pharmacological differences between these three diuretics, as well as the clinical trial data and important side effects.

Pharmaceutical meaning-making beyond marketing: racialized subjects of generic thiazide.

PubMed

Pollock, Anne

2008-01-01

In contrast to discussions of BiDil, this paper explores racial meaning-making processes around an old generic hypertension drug. By unpacking a vignette about race and thiazide outside marketing or medicine, it shows that racialization of drugs exceeds those spheres and moves in unpredictable ways.

Diuretics in the treatment of hypertension.

PubMed

Blowey, Douglas L

2016-12-01

Diuretics have long been used for the treatment of hypertension. Thiazide diuretics are the most commonly prescribed diuretics for hypertension, but other classes of diuretics may be useful in alternative circumstances. Although diuretics are no longer considered the preferred agent for treatment of hypertension in adults and children, they remain acceptable first-line options. Diuretics effectively decrease blood pressure in hypertensive patients, and in adults with hypertension reduce the risk of adverse cardiovascular outcomes. Because of varied pharmacokinetic and pharmacodynamic differences, chlorthalidone may be the preferred thiazide diuretic in the treatment of primary hypertension. Other types of diuretics (e.g., loop, potassium sparing) may be useful for the treatment of hypertension related to chronic kidney disease (CKD) and other varied conditions. Common side effects of thiazides are mostly dose-related and involve electrolyte and metabolic abnormalities.

Rational Prescribing in Primary Care (RaPP): Economic Evaluation of an Intervention to Improve Professional Practice

PubMed Central

Fretheim, Atle; Aaserud, Morten; Oxman, Andrew D

2006-01-01

Background Interventions designed to narrow the gap between research findings and clinical practice may be effective, but also costly. Economic evaluations are necessary to judge whether such interventions are worth the effort. We have evaluated the economic effects of a tailored intervention to support the implementation of guidelines for the use of antihypertensive and cholesterol-lowering drugs. The tailored intervention was evaluated in a randomized trial, and was shown to significantly increase the use of thiazides for patients started on antihypertensive medication, but had little or no impact on other outcomes. The increased use of thiazides was not expected to have an impact on health outcomes. Methods and Findings We performed cost-minimization and cost-effectiveness analyses on data from a randomized trial involving 146 general practices from two geographical areas in Norway. Each practice was randomized to either the tailored intervention (70 practices; 257 physicians) or control group (69 practices; 244 physicians). Only patients that were being started on antihypertensive medication were included in the analyses. A multifaceted intervention was tailored to address identified barriers to change. Key components were an educational outreach visit with audit and feedback, and computerized reminders. Pharmacists conducted the visits. A cost-minimization framework was adopted, where the costs of intervention were set against the reduced treatment costs (principally due to increased use of thiazides rather than more expensive medication). The cost-effectiveness of the intervention was estimated as the cost per additional patient being started on thiazides. The net annual cost (cost minimization) in our study population was US$53,395, corresponding to US$763 per practice. The cost per additional patient started on thiazides (cost-effectiveness) was US$454. The net annual savings in a national program was modeled to be US$761,998, or US$540 per practice after 2 y. In this scenario the savings exceeded the costs in all but two of the sensitivity analyses we conducted, and the cost-effectiveness was estimated to be US$183. Conclusions We found a significant shift in prescribing of antihypertensive drugs towards the use of thiazides in our trial. A major reason to promote the use of thiazides is their lower price compared to other drugs. The cost of the intervention was more than twice the savings within the time frame of our study. However, we predict modest savings over a 2-y period. PMID:16737349

Initial antihypertensive prescription and switching: a 5 year cohort study from 250,851 patients.

PubMed

Wong, Martin C S; Tam, Wilson W S; Cheung, Clement S K; Tong, Ellen L H; Sek, Antonio C H; John, George; Cheung, N T; Yan, Bryan P Y; Yu, C M; Leeder, Stephen; Griffiths, Sian

2013-01-01

Adverse effects of antihypertensive therapy incur substantial cost. We evaluated whether any major classes of antihypertensive drugs were significantly associated with switching as a proxy measure of medication side effects in a large Chinese population in Hong Kong. From a clinical database, all adult patients newly prescribed an antihypertensive mono-therapy in Hong Kong between the years 2001-2003 and 2005 were included. Those who paid only one visit, died or stayed in the cohort for <180 days after the prescription, or prescribed more than one antihypertensive agent were excluded. The factors associated with switching at 180 days were evaluated by multivariate regression analyses. Age, gender, payment status, service type, district of residence, drug class, systolic and diastolic blood pressure levels were predictor variables. From 250,851 subjects, 159,813 patients were eligible. A total of 6,163 (3.9%) switched their medications within 180 days. Patients prescribed thiazide diuretics had the highest switching rate (5.6%), followed by ACEIs (4.5%), CCBs (4.4%) and beta-blockers (3.2%). When compared with ACEIs, patients on thiazide diuretics were significantly more likely to be switchers (adjusted odds ratio [AOR] 1.49, 95% C.I. 1.31-1.69, p<0.001), whilst patients prescribed CCBs and beta-blockers were similarly likely to have switching. Following these patients up for 5 years showed that thiazide had the most marked increase in switching rate. The higher rates of switching among thiazide diuretics in this study might raise a probably greater incidence of their adverse effects in this Chinese population, yet other factors might also influence switching rates. Patients prescribed thiazide diuretics for longer term should be observed for their intolerability.

Loop Diuretics in the Treatment of Hypertension.

PubMed

Malha, Line; Mann, Samuel J

2016-04-01

Loop diuretics are not recommended in current hypertension guidelines largely due to the lack of outcome data. Nevertheless, they have been shown to lower blood pressure and to offer potential advantages over thiazide-type diuretics. Torsemide offers advantages of longer duration of action and once daily dosing (vs. furosemide and bumetanide) and more reliable bioavailability (vs. furosemide). Studies show that the previously employed high doses of thiazide-type diuretics lower BP more than furosemide. Loop diuretics appear to have a preferable side effect profile (less hyponatremia, hypokalemia, and possibly less glucose intolerance). Studies comparing efficacy and side effect profiles of loop diuretics with the lower, currently widely prescribed, thiazide doses are needed. Research is needed to fill gaps in knowledge and common misconceptions about loop diuretic use in hypertension and to determine their rightful place in the antihypertensive arsenal.

[Classical antihypertensive drugs: diuretics].

PubMed

Nagy, Viktor László

2017-03-01

The diuretics are essential medicaments of antihypertensive therapy. They reduce blood pressure and cardiovascular events optimally. With increasing doses of thiazides and thiazide analogs do not come further powerful effect of reducing blood pressure or cardiovascular mortality and morbidity, but clearly elevate the side effects. Because of it, the minimum effective dose level and the fixed-dose combination therapy should be preferred. The use these drugs leads to especially positive outcome in elder patients, isolated systolic hypertension, heart failure, after stroke and in black population. Loop diuretics as antihypertensive therapy can be used only by renal impairment. The use of aldosterone antagonists can have a good effect not only on heart failure but also on prevention of atrial fibrillation. Furthermore, using it in a combination therapy with thiazides, it reduces the risk of hypokalemia. Therefore, the diuretic treatment in hypertension is flourishing again. Orv. Hetil., 2017, 158(11), 403-408.

Add-On Antihypertensive Medications to Angiotensin-Aldosterone System Blockers in Diabetes: A Comparative Effectiveness Study.

PubMed

Schroeder, Emily B; Chonchol, Michel; Shetterly, Susan M; Powers, J David; Adams, John L; Schmittdiel, Julie A; Nichols, Gregory A; O'Connor, Patrick J; Steiner, John F

2018-05-07

In individuals with diabetes, the comparative effectiveness of add-on antihypertensive medications added to an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker on the risk of significant kidney events is unknown. We used an observational, multicenter cohort of 21,897 individuals with diabetes to compare individuals who added β -blockers, dihydropyridine calcium channel blockers, loop diuretics, or thiazide diuretics to angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. We examined the hazard of significant kidney events, cardiovascular events, and death using Cox proportional hazard models with propensity score weighting. The composite significant kidney event end point was defined as the first occurrence of a ≥30% decline in eGFR to an eGFR<60 ml/min per 1.73 m 2 , initiation of dialysis, or kidney transplant. The composite cardiovascular event end point was defined as the first occurrence of hospitalization for acute myocardial infarction, acute coronary syndrome, stroke, or congestive heart failure; coronary artery bypass grafting; or percutaneous coronary intervention, and it was only examined in those free of cardiovascular disease at baseline. Over a maximum of 5 years, there were 4707 significant kidney events, 1498 deaths, and 818 cardiovascular events. Compared with thiazide diuretics, hazard ratios for significant kidney events for β -blockers, calcium channel blockers, and loop diuretics were 0.81 (95% confidence interval, 0.74 to 0.89), 0.67 (95% confidence interval, 0.58 to 0.78), and 1.19 (95% confidence interval, 1.00 to 1.41), respectively. Compared with thiazide diuretics, hazard ratios of mortality for β -blockers, calcium channel blockers, and loop diuretics were 1.19 (95% confidence interval, 0.97 to 1.44), 0.73 (95% confidence interval, 0.52 to 1.03), and 1.67 (95% confidence interval, 1.31 to 2.13), respectively. Compared with thiazide diuretics, hazard ratios of cardiovascular events for β -blockers, calcium channel blockers, and loop diuretics compared with thiazide diuretics were 1.65 (95% confidence interval, 1.39 to 1.96), 1.05 (95% confidence interval, 0.80 to 1.39), and 1.55 (95% confidence interval, 1.05 to 2.27), respectively. Compared with thiazide diuretics, calcium channel blockers were associated with a lower risk of significant kidney events and a similar risk of cardiovascular events. Copyright © 2018 by the American Society of Nephrology.

Thiazide increases serum calcium in anuric patients: the role of parathyroid hormone.

PubMed

Vasco, Raquel F V; Reis, Eduardo T; Moyses, Rosa M A; Elias, Rosilene M

2017-12-01

We evaluated the effect of hydrochlorothiazide in a sample of anuric patients on hemodialysis and found an increase in serum calcium, which occurred only in those with parathyroid hormone >300 pg/ml. This finding highlights the extra-renal effect of this diuretic and a possible role of parathyroid hormone in the mechanism. Thiazide diuretics are commonly used in patients with chronic kidney disease to treat hypertension. Their effects on calcium and bone metabolism are not well established, once calciuria may not fully explain levels of calcium and parathyroid hormone (PTH) in this population. A previous study has suggested that thiazides require the presence of PTH as a permissive condition for its renal action. In anuric patients, however, the role of PTH, if any, in the thiazide effect is unknown. To assess thiazide extra renal effect on serum calcium and whether such an effect is reliant on PTH, hydrochlorothiazide (HCTZ) 100 mg was given orally once a day to a sample of 19 anuric patients on hemodialysis for 2 weeks. Laboratories' analyses were obtained in three phases: baseline, after diuretic use, and after a 2-week washout phase. We demonstrated that serum calcium (Ca) increased in ten patients (52.6%) after HCTZ use, returning to previous levels after the washout period. Out of the 19 patients, ten presented PTH ≥ 300 pg/ml, and Ca has increased in eight of them, whereas in the other nine patients with PTH < 300 pg/ml, serum Ca has increased only in two individuals (RR risk of increase Ca 3.9; p = 0.012). HCTZ was capable of increasing serum Ca in a sample of anuric patients on hemodialysis and seems this effect is highly dependent on PTH levels. Caution is required while interpreting this result, as the small sample size might implicate in a finding caused by chance.

The role of calbindin-D28k on renal calcium and magnesium handling during treatment with loop and thiazide diuretics

PubMed Central

Lee, Chien-Te; Ng, Hwee-Yeong; Lee, Yueh-Ting; Lai, Li-Wen

2015-01-01

Calbindin-D28k (CBD-28k) is a calcium binding protein located in the distal convoluted tubule (DCT) and plays an important role in active calcium transport in the kidney. Loop and thiazide diuretics affect renal Ca and Mg handling: both cause Mg wasting, but have opposite effects on Ca excretion as loop diuretics increase, but thiazides decrease, Ca excretion. To understand the role of CBD-28k in renal Ca and Mg handling in response to diuretics treatment, we investigated renal Ca and Mg excretion and gene expression of DCT Ca and Mg transport molecules in wild-type (WT) and CBD-28k knockout (KO) mice. Mice were treated with chlorothiazide (CTZ; 50 mg·kg−1·day−1) or furosemide (FSM; 30 mg·kg−1·day−1) for 3 days. To avoid volume depletion, salt was supplemented in the drinking water. Urine Ca excretion was reduced in WT, but not in KO mice, by CTZ. FSM induced similar hypercalciuria in both groups. DCT Ca transport molecules, including transient receptor potential vanilloid 5 (TRPV5), TRPV6, and CBD-9k, were upregulated by CTZ and FSM in WT, but not in KO mice. Urine Mg excretion was increased and transient receptor potential subfamily M, member 6 (TRPM6) was upregulated by both CTZ and FSM in WT and KO mice. In conclusion, CBD-28k plays an important role in gene expression of DCT Ca, but not Mg, transport molecules, which may be related to its being a Ca, but not a Mg, intracellular sensor. The lack of upregulation of DCT Ca transport molecules by thiazides in the KO mice indicates that the DCT Ca transport system is critical for Ca conservation by thiazides. PMID:26582761

Do advertisements for antihypertensive drugs in Australia promote quality prescribing? A cross-sectional study.

PubMed

Montgomery, Brett D; Mansfield, Peter R; Spurling, Geoffrey K; Ward, Alison M

2008-05-20

Antihypertensive medications are widely prescribed by doctors and heavily promoted by the pharmaceutical industry. Despite strong evidence of the effectiveness and cost-effectiveness of thiazide diuretics, trends in both promotion and prescription of antihypertensive drugs favour newer, less cost-effective agents. Observational evidence shows correlations between exposure to pharmaceutical promotion and less ideal prescribing. Our study therefore aimed to determine whether print advertisements for antihypertensive medications promote quality prescribing in hypertension. We performed a cross-sectional study of 113 advertisements for antihypertensive drugs from 4 general practice-oriented Australian medical publications in 2004. Advertisements were evaluated using a quality checklist based on a review of hypertension management guidelines. Main outcome measures included: frequency with which antihypertensive classes were advertised, promotion of thiazide class drugs as first line agents, use of statistical claims in advertisements, mention of harms and prices in the advertisements, promotion of assessment and treatment of cardiovascular risk, promotion of lifestyle modification, and targeting of particular patient subgroups. Thiazides were the most frequently advertised drug class (48.7% of advertisements), but were largely promoted in combination preparations. The only thiazide advertised as a single agent was the most expensive, indapamide. No advertisement specifically promoted any thiazide as a better first-line drug. Statistics in the advertisements tended to be expressed in relative rather than absolute terms. Drug costs were often reported, but without cost comparisons between drugs. Adverse effects were usually reported but largely confined to the advertisements' small print. Other than mentioning drug interactions with alcohol and salt, no advertisements promoted lifestyle modification. Few advertisements (2.7%) promoted the assessment of cardiovascular risk. Print advertisements for antihypertensive medications in Australia provide some, but not all, of the key messages required for guideline-concordant care. These results have implications for the regulation of drug advertising and the continuing education of doctors.

Efficacy of azilsartan medoxomil with chlorthalidone in hypertension.

PubMed

Baker, William L; Nigro, Stefanie C; White, William B

2014-07-01

Azilsartan medoxomil (AZL) is the most recently approved angiotensin receptor blocker (ARB) for treating patients with hypertension. A fixed-dose combination product with AZL and the thiazide-like diuretic chlorthalidone (CLD) is now available to treat individuals who require additional blood pressure lowering. For this review, a literature search was conducted using MEDLINE and the keywords and MeSH terms azilsartan, azilsartan medoxomil, chlorthalidone, thiazide, blood pressure and hypertension. References for retrieved articles were also scanned for relevant citations. No language restrictions were used. AZL is structurally related to candesartan and has been shown to provide more potent angiotensin receptor antagonism versus other ARBs. CLD is a thiazide-like diuretic with a longer half-life and greater blood pressure lowering efficacy than hydrochlorothiazide. The combination of AZL plus CLD has superior efficacy to other ARBs alone or in combination with hydrochlorothiazide based on extensive evaluation in clinical trials. This superior efficacy is not offset by a large imbalance in clinically important adverse events.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beyer, K.H. Jr.; Fehr, D.M.; Gelarden, R.T.

Salt intake is restricted under clinical conditions for which thiazide diuretics are customarily used. Dietary iodide intake offsets any effect of thiazide on iodide loss. However, our correlation coefficients relating Na+ to Cl- to I- excretion indicate that as thiazide administration or sodium chloride intake increases renal Na+ and Cl- excretion, I- reabsorption by the nephron coordinately decreases. Increased sodium chloride and water intake by the dog doubled I-excretion rates. Hydrochlorothiazide increased the sodium chloride and water enhanced I-excretion rate as much as eight-fold. Without added NaCl, hydrochlorothiazide increased the excretion rate of 131I by three- to eightfold, acutely. Withinmore » five to seven days after 131I oral administration, hydrochlorothiazide (1 or 2 mg/kg twice daily) doubled the rate of 131I disappearance from plasma, reduced the fecal output of 131I, and increased its rate of renal excretion. When hydrochlorothiazide was administered, as much 131I was excreted in the first 24 hours as occurred in 48 hours when sodium chloride and water were given without hydrochlorothiazide. Thiazide administration in customary clinical dosage twice a day with substantial sodium chloride and water for the first two days after exposure to 131I, should therefore facilitate the safe excretion of 131I. This accelerated removal of 131I might be enhanced even more if thyroid uptake of 131I is blocked by administration of potassium iodide, as judged by the greater 131I recovery from thyroidectomized dogs.« less

Nephrogenic diabetes insipidus: treat with caution.

PubMed

Boussemart, Thierry; Nsota, Jacqueline; Martin-Coignard, Dominique; Champion, Gérard

2009-09-01

Current therapy for congenital nephrogenic diabetes insipidus consists of appropriate water intake coupled with decreased urine output obtained by means of a low-sodium diet and a combination of thiazide diuretics with renal prostaglandins inhibitors or amiloride. We report a case of congenital nephrogenic diabetes insipidus that was complicated by paradoxical water intoxication secondary to liberal water intake and the initiation of hydrochlorothiazide and indomethacin combination therapy. This report emphasizes the importance of evaluating the water balance and of a quick response with strict protocols following the initiation of indomethacin and thiazide diuretics in nephrogenic diabetes insipidus.

Medical management to prevent recurrent nephrolithiasis in adults: a systematic review for an American College of Physicians Clinical Guideline.

PubMed

Fink, Howard A; Wilt, Timothy J; Eidman, Keith E; Garimella, Pranav S; MacDonald, Roderick; Rutks, Indulis R; Brasure, Michelle; Kane, Robert L; Ouellette, Jeannine; Monga, Manoj

2013-04-02

Optimum management to prevent recurrent kidney stones is uncertain. To evaluate the benefits and harms of interventions to prevent recurrent kidney stones. MEDLINE, Cochrane, and other databases through September 2012 and reference lists of systematic reviews and randomized, controlled trials (RCTs). 28 English-language RCTs that studied treatments to prevent recurrent kidney stones and reported stone outcomes. One reviewer extracted data, a second checked accuracy, and 2 independently rated quality and graded strength of evidence. In patients with 1 past calcium stone, low-strength evidence showed that increased fluid intake halved recurrent composite stone risk compared with no treatment (relative risk [RR], 0.45 [95% CI, 0.24 to 0.84]). Low-strength evidence showed that reducing soft-drink consumption decreased recurrent symptomatic stone risk (RR, 0.83 [CI, 0.71 to 0.98]). In patients with multiple past calcium stones, most of whom were receiving increased fluid intake, moderate-strength evidence showed that thiazides (RR, 0.52 [CI, 0.39 to 0.69]), citrates (RR, 0.25 [CI, 0.14 to 0.44]), and allopurinol (RR, 0.59 [CI, 0.42 to 0.84]) each further reduced composite stone recurrence risk compared with placebo or control, although the benefit from allopurinol seemed limited to patients with baseline hyperuricemia or hyperuricosuria. Other baseline biochemistry measures did not allow prediction of treatment efficacy. Low-strength evidence showed that neither citrate nor allopurinol combined with thiazide was superior to thiazide alone. There were few withdrawals among patients with increased fluid intake, many among those with other dietary interventions and more among those who received thiazide and citrate than among control patients. Reporting of adverse events was poor. Most trial participants had idiopathic calcium stones. Nearly all studies reported a composite (including asymptomatic) stone recurrence outcome. In patients with 1 past calcium stone, increased fluid intake reduced recurrence risk. In patients with multiple past calcium stones, addition of thiazide, citrate, or allopurinol further reduced risk. Agency for Healthcare Research and Quality.

Methodology to Estimate the Longitudinal Average Attributable Fraction of Guideline-recommended Medications for Death in Older Adults With Multiple Chronic Conditions

PubMed Central

Zhan, Yilei; Cohen, Andrew B.; Tinetti, Mary E.; Trentalange, Mark; McAvay, Gail

2016-01-01

Background: Persons with multiple chronic conditions receive multiple guideline-recommended medications to improve outcomes such as mortality. Our objective was to estimate the longitudinal average attributable fraction for 3-year survival of medications for cardiovascular conditions in persons with multiple chronic conditions and to determine whether heterogeneity occurred by age. Methods: Medicare Current Beneficiary Survey participants (N = 8,578) with two or more chronic conditions, enrolled from 2005 to 2009 with follow-up through 2011, were analyzed. We calculated the longitudinal extension of the average attributable fraction for oral medications (beta blockers, renin–angiotensin system blockers, and thiazide diuretics) indicated for cardiovascular conditions (atrial fibrillation, coronary artery disease, heart failure, and hypertension), on survival adjusted for 18 participant characteristics. Models stratified by age (≤80 and >80 years) were analyzed to determine heterogeneity of both cardiovascular conditions and medications. Results: Heart failure had the greatest average attributable fraction (39%) for mortality. The fractional contributions of beta blockers, renin–angiotensin system blockers, and thiazides to improve survival were 10.4%, 9.3%, and 7.2% respectively. In age-stratified models, of these medications thiazides had a significant contribution to survival only for those aged 80 years or younger. The effects of the remaining medications were similar in both age strata. Conclusions: Most cardiovascular medications were attributed independently to survival. The two cardiovascular conditions contributing independently to death were heart failure and atrial fibrillation. The medication effects were similar by age except for thiazides that had a significant contribution to survival in persons younger than 80 years. PMID:26748093

Constitutively Active SPAK Causes Hyperkalemia by Activating NCC and Remodeling Distal Tubules.

PubMed

Grimm, P Richard; Coleman, Richard; Delpire, Eric; Welling, Paul A

2017-09-01

Aberrant activation of with no lysine (WNK) kinases causes familial hyperkalemic hypertension (FHHt). Thiazide diuretics treat the disease, fostering the view that hyperactivation of the thiazide-sensitive sodium-chloride cotransporter (NCC) in the distal convoluted tubule (DCT) is solely responsible. However, aberrant signaling in the aldosterone-sensitive distal nephron (ASDN) and inhibition of the potassium-excretory renal outer medullary potassium (ROMK) channel have also been implicated. To test these ideas, we introduced kinase-activating mutations after Lox-P sites in the mouse Stk39 gene, which encodes the terminal kinase in the WNK signaling pathway, Ste20-related proline-alanine-rich kinase (SPAK). Renal expression of the constitutively active (CA)-SPAK mutant was specifically targeted to the early DCT using a DCT-driven Cre recombinase. CA-SPAK mice displayed thiazide-treatable hypertension and hyperkalemia, concurrent with NCC hyperphosphorylation. However, thiazide-mediated inhibition of NCC and consequent restoration of sodium excretion did not immediately restore urinary potassium excretion in CA-SPAK mice. Notably, CA-SPAK mice exhibited ASDN remodeling, involving a reduction in connecting tubule mass and attenuation of epithelial sodium channel (ENaC) and ROMK expression and apical localization. Blocking hyperactive NCC in the DCT gradually restored ASDN structure and ENaC and ROMK expression, concurrent with the restoration of urinary potassium excretion. These findings verify that NCC hyperactivity underlies FHHt but also reveal that NCC-dependent changes in the driving force for potassium secretion are not sufficient to explain hyperkalemia. Instead, a DCT-ASDN coupling process controls potassium balance in health and becomes aberrantly activated in FHHt. Copyright © 2017 by the American Society of Nephrology.

Diuretics and disorders of calcium homeostasis.

PubMed

Grieff, Marvin; Bushinsky, David A

2011-11-01

Diuretics commonly are administered in disorders of sodium balance. Loop diuretics inhibit the Na-K-2Cl transporter and also increase calcium excretion. They are often used in the treatment of hypercalcemia. Thiazide diuretics block the thiazide-sensitive NaCl transporter in the distal convoluted tubule, and can decrease calcium excretion. They are often used in the treatment of nephrolithiasis. Carbonic anhydrase inhibitors decrease bicarbonate absorption and the resultant metabolic acidosis can increase calcium excretion. Their use can promote nephrocalcinosis and nephrolithiasis. This review will address the use of diuretics on disorders of calcium homeostasis. Copyright © 2011 Elsevier Inc. All rights reserved.

[Thiazide diuretics in the treatment of hypertensive patients].

PubMed

Rasmussen, Knud

2015-05-11

This Cochrane review had the objectives to determine the dose-related decrease in blood pressure due to thiazide diuretics compared with placebo control in the treatment of hypertensive patients. Hydrochlorothiazide has a dose-related blood pressure-lowering effect over the dose range 6.25, 12.5, 25 and 50 mg/day of 4/2, 6/3, 8/3 and 11/5 mmHg, respectively. This exceeds the mean 3 mmHg reduction achieved by angiotensin-converting-enzyme inhibitors and angiotensin receptor blockers as shown in other Cochrane reviews, which have compared these antihypertensive drugs with placebo having used similar inclusion/exclusion criteria.

A randomized controlled trial of the effects of aerobic dance training on blood lipids among individuals with hypertension on a thiazide.

PubMed

Maruf, Fatai A; Akinpelu, Aderonke O; Salako, Babatunde L

2014-12-01

Hypertension is associated with dyslipidemia. Thiazides adversely affect serum lipid levels in hypertensives. There is currently a dearth of information on benefits of aerobic exercise training on serum lipid levels in individuals on thiazides and this study aimed at bridging this gap in knowledge. This randomized-controlled trial involved 120 newly-diagnosed adults with essential hypertension (≥65 years). They were treated with 50 mg of hydrochlorothiazide + 5 mg of hydrochloride amiloride and 5 or 10 mg of amlodipine for 4-6 weeks before they were randomly assigned into exercise group (EG) and control croup (CG). Only EG underwent 12-week aerobic dance training at 50-70 % of heart rate reserve three times per week. Low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, triglyceride and total cholesterol were measured and recorded at baseline and post-study. Eighty-eight (45 in EG and 43 in CG) of 120 participants randomly assigned to groups completed the study. Systolic (p = 0.370) and diastolic (p = 0.771) blood pressures (BP) were similar between the two groups at baseline. Systolic (p < 0.001) and diastolic (p < 0.001) BPs reduced significantly in exercise and control groups. LDL-C (from 120.10 ± 33.41 to 110.50 ± 31.68 mg/dl; p = 0.037) and triglyceride (from 117.49 ± 45.12 to 100.63 ± 35.42 mg/dl; p = 0.002) decreased in EG post-study but no significant between-group differences were observed. Although, LDL-C and triglyceride are reduced after aerobic dance training, they were not any more than without it. Aerobic dance training has favorable effects on LDL-C, triglyceride, and systolic and diastolic BP in individuals with hypertension on a thiazide.

Rationale and Design of the "Safety and Efficacy of the Combination of Loop with Thiazide-type Diuretics in Patients with Decompensated Heart Failure (CLOROTIC) Trial:" A Double-Blind, Randomized, Placebo-Controlled Study to Determine the Effect of Combined Diuretic Therapy (Loop Diuretics With Thiazide-Type Diuretics) Among Patients With Decompensated Heart Failure.

PubMed

Trullàs, Joan Carles; Morales-Rull, José Luís; Casado, Jesús; Freitas Ramírez, Adriana; Manzano, Luís; Formiga, Francesc

2016-07-01

Fluid overload refractory to loop diuretic therapy can complicate acute or chronic heart failure (HF) management. The Safety and Efficacy of the Combination of Loop with Thiazide-type Diuretics in Patients with Decompensated Heart Failure (CLOROTIC) trial (Clinicaltrials.gov identifier NCT01647932) will test the hypothesis that blocking distal tubule sodium reabsorption with hydrochlorothiazide can antagonize the renal adaptation to chronic loop diuretic therapy and improve diuretic resistance. CLOROTIC is a randomized, placebo-controlled, double-blind, multicenter study. Three hundred and four patients with decompensated HF will be randomly assigned to receive hydrochlorothiazide or placebo in addition to a furosemide regimen. The main inclusion criteria are: age ≥18 years, history of chronic HF (irrespective of etiology and/or ejection fraction), admission for acute decompensation, and previous treatment with an oral loop diuretic for at least 1 month before randomization. The 2 coprimary endpoints are changes in body weight and changes in patient-reported dyspnea during hospital admission. Morbidity, mortality, and safety aspects will also be addressed. CLOROTIC is the first large-scale trial to evaluate whether the addition of a thiazide diuretic (hydrochlorothiazide) to a loop diuretic (furosemide) is a safe and effective strategy for improving congestive symptoms resulting from HF. This trial will provide important information and will therefore have a major impact on treatment strategies and future trials in these patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Diuretics for Hypertension: A Review and Update.

PubMed

Roush, George C; Sica, Domenic A

2016-10-01

This review and update focuses on the clinical features of hydrochlorothiazide (HCTZ), the thiazide-like agents chlorthalidone (CTDN) and indapamide (INDAP), potassium-sparing ENaC inhibitors and aldosterone receptor antagonists, and loop diuretics. Diuretics are the second most commonly prescribed class of antihypertensive medication, and thiazide-related diuretics have increased at a rate greater than that of antihypertensive medications as a whole. The latest hypertension guidelines have underscored the importance of diuretics for all patients, but particularly for those with salt-sensitive and resistant hypertension. HCTZ is 4.2-6.2 systolic mm Hg less potent than CTDN, angiotensin-converting enzyme inhibitors, beta blockers, and calcium channel blockers by 24-hour measurements and 5.1mm Hg systolic less potent than INDAP by office measurements. For reducing cardiovascular events (CVEs), HCTZ is less effective than enalapril and amlodipine in randomized trials, and, in network analysis of trials, it is less effective than CTDN and HCTZ-amiloride. Combined with thiazide-type diuretics, potassium-sparing agents decrease ventricular ectopy and reduce the risk for sudden cardiac death relative to thiazide-type diuretics used alone. A recent synthesis of 44 trials has shown that the relative potencies in milligrams among spironolactone (SPIR), amiloride, and eplerenone (EPLER) are approximately from 25 to 10 to 100, respectively, which may be important when SPIR is poorly tolerated. SPIR reduces proteinuria beyond that provided by other renin angiotensin aldosterone inhibitors. EPLER also reduces proteinuria and has beneficial effects on endothelial function. While guidelines often do not differentiate among specific diuretics, this review demonstrates that these distinctions are important for managing hypertension. © American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Thiazide-sensitive Na+ -Cl- cotransporter (NCC) gene inactivation results in increased duodenal Ca2+ absorption, enhanced osteoblast differentiation and elevated bone mineral density.

PubMed

Hsu, Yu-Juei; Yang, Sung-Sen; Cheng, Chih-Jen; Liu, Shu-Ting; Huang, Shih-Ming; Chau, Tom; Chu, Pauling; Salter, Donald M; Lee, Herng-Sheng; Lin, Shih-Hua

2015-01-01

Inactivation of the thiazide-sensitive sodium chloride cotransporter (NCC) due to genetic mutations in Gitelman's syndrome (GS) or pharmacological inhibition with thiazide diuretics causes hypocalciuria and increased bone mineral density (BMD) with unclear extrarenal calcium (Ca(2+) ) regulation. We investigated intestinal Ca(2+) absorption and bone Ca(2+) metabolism in nonsense Ncc Ser707X (S707X) homozygous knockin mice (Ncc(S707X/S707X) mice). Compared to wild-type and heterozygous knockin littermates, Ncc(S707X/S707X) mice had increased intestinal absorption of (45) Ca(2+) and expression of the active Ca(2+) transport machinery (transient receptor potential vanilloid 6, calbindin-D9K , and plasma membrane Ca(2+) ATPase isoform 1b). Ncc(S707X/S707X) mice had also significantly increased Ca(2+) content accompanied by greater mineral apposition rate (MAR) in their femurs and higher trabecular bone volume, cortical bone thickness, and BMD determined by μCT. Their osteoblast differentiation markers, such as bone alkaline phosphatase, procollagen I, osteocalcin, and osterix, were also significantly increased while osteoclast activity was unaffected. Analysis of marrow-derived bone cells, either treated with thiazide or directly cultured from Ncc S707X knockin mice, showed that the differentiation of osteoblasts was associated with increased phosphorylation of mechanical stress-induced focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK). In conclusion, NCC inhibition stimulates duodenal Ca(2+) absorption as well as osteoblast differentiation and bone Ca(2+) storage, possibly through a FAK/ERK dependent mechanism. © 2014 American Society for Bone and Mineral Research.

Are thiazides effective on hypertensive vertigo? A preliminary study.

PubMed

Eryaman, Esra; Gökcan, Gökçen; Parmaksız, Ergün; Acar, Nurhan Ozdemir; Ozlüoğlu, Levent Naci

2012-01-01

In this study, we aimed to investigate whether the symptoms of vertigo related to hypertension resulted from endolymphatic hydrops and the efficacy of the thiazides in the treatment. A total of 24 vertigo patients without peripheric or central vestibular pathologies or hyperlipidemia were included. The study group comprised 15 patients with hypertension, including nine with regulated non-insulin-dependent diabetes mellitus (DM). The control group comprised nine patients without hypertension or DM. The patients in the study group received hydrochlorothiazide treatment. The European Evaluation of Vertigo Scale (EEVS) and Vertigo Handicap Questionnaire (VHQ), puretone audiometry, tympanometry, electronystagmography (ENG) for nystagmus tests, oculomotor tests, and caloric test were carried out initially and at three weeks for both groups. The results of the study group were compared to those of the control group. There was a statistically significant decrease in the scores of EEVS and VHQ at three weeks in the study group, compared to the baseline scores (for both groups p≤0.01). Our study results showed that thiazides alleviated vertigo symptoms in hypertensive patients, as measured by qualitative methods (i.e. EEVS, VHQ), but not with quantitative measurements (i.e. ENG).

Impact of long-term potassium supplementation on thiazide diuretic-induced abnormalities of glucose and uric acid metabolisms.

PubMed

Zhang, Jian-Liang; Yu, Hui; Hou, Ying-Wei; Wang, Ke; Bi, Wen-Shan; Zhang, Liang; Wang, Qian; Li, Pan; Yu, Man-Li; Zhao, Xian-Xian

2018-04-01

Treatment of hypertension with thiazide diuretics may trigger hypokalemia, hyperglycemia, and hyperuricemia. Some studies suggest simultaneous potassium supplementation in hypertensive patients using thiazide diuretics. However, few clinical studies have reported the impact of long-term potassium supplementation on thiazide diuretic-induced abnormalities in blood glucose and uric acid (UA) metabolisms. One hundred hypertensive patients meeting the inclusion criteria were equally randomized to two groups: IND group receiving indapamide (1.25-2.5 mg daily) alone, and IND/KCI group receiving IND (1.25-2.5 mg daily) plus potassium chloride (40 mmol daily), both for 24 weeks. At the end of 24-week follow-up, serum K + level in IND group decreased from 4.27 ± 0.28 to 3.98 ± 0.46 mmol/L (P < 0.001), and fasting plasma glucose (FPG) and UA increased from 5.11 ± 0.52 to 5.31 ± 0.57 mmol/L (P < 0.05), and from 0.404 ± 0.078 to 0.433 ± 0.072 mmol/L (P < 0.05), respectively. Serum K + level in IND/KCl group decreased from 4.27 ± 0.36 to 3.89 ± 0.28 mmol/L (P < 0.001), and FPB and UA increased from 5.10 ± 0.41 to 5.35 ± 0.55 mmol/L (P < 0.01), and from 0.391 ± 0.073 to 0.457 ± 0.128 mmol/L (P < 0.001), respectively. The difference value between the serum K + level and FPG before and after treatment was not statistically significant between the two groups. However, the difference value in UA in IND/KCl group was significantly higher than that in IND group (0.066 (95% confidence interval (CI): 0.041-0.090)  mmol/L vs. 0.029 (95% CI: 0.006-0.058) mmol/L, P < 0.05). The results showed that long-term routine potassium supplementation could not prevent or attenuate thiazide diuretic-induced abnormalities of glucose metabolism in hypertensive patients; rather, it may aggravate the UA metabolic abnormality.

Circadian exosomal expression of renal thiazide-sensitive NaCl cotransporter (NCC) and prostasin in healthy individuals.

PubMed

Castagna, Annalisa; Pizzolo, Francesca; Chiecchi, Laura; Morandini, Francesca; Channavajjhala, Sarath Kiran; Guarini, Patrizia; Salvagno, Gianluca; Olivieri, Oliviero

2015-06-01

A circadian timing system is involved in the maintenance of fluid and electrolyte balance and blood pressure control. Aldosterone and vasopressin modulate ion transporters and channels crucial in sodium (Na) and water reabsorption such as the epithelium Na channel and the renal thiazide-sensitive NaCl cotransporter (NCC). We analyzed in urinary exosomes the intraday variations of NCC and prostasin expression and the association with electrolytes and water balance parameters. Blood and urine samples were collected at five time points during the day from five healthy subjects. Blood renin, aldosterone, cortisol, ACTH, and plasmatic and urinary Na, potassium, creatinine, adiuretin (ADH), NCC, and prostasin were evaluated. ACTH and cortisol showed a circadian pattern, similarly to aldosterone, while exosomal NCC and prostasin pattern were similar to urinary ADH, decreased in the morning and subsequently increased in the afternoon and evening. In urinary exosomes, NCC and prostasin had a diurnal pattern parallel to ADH and aquaporin 2, confirming that, in healthy subjects, both prostasin and NCC relate to water balance. These results provide suggestions for a possible chronotherapeutic approach in patients treated with thiazides, diuretic drugs acting as specific inhibitors of NCC-mediated Na reabsorption. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Engineering practice variation through provider agreement: a cluster-randomized feasibility trial.

PubMed

McCarren, Madeline; Twedt, Elaine L; Mansuri, Faizmohamed M; Nelson, Philip R; Peek, Brian T

2014-01-01

Minimal-risk randomized trials that can be embedded in practice could facilitate learning health-care systems. A cluster-randomized design was proposed to compare treatment strategies by assigning clusters (eg, providers) to "favor" a particular drug, with providers retaining autonomy for specific patients. Patient informed consent might be waived, broadening inclusion. However, it is not known if providers will adhere to the assignment or whether institutional review boards will waive consent. We evaluated the feasibility of this trial design. Agreeable providers were randomized to "favor" either hydrochlorothiazide or chlorthalidone when starting patients on thiazide-type therapy for hypertension. The assignment applied when the provider had already decided to start a thiazide, and providers could deviate from the strategy as needed. Prescriptions were aggregated to produce a provider strategy-adherence rate. All four institutional review boards waived documentation of patient consent. Providers (n=18) followed their assigned strategy for most of their new thiazide prescriptions (n=138 patients). In the "favor hydrochlorothiazide" group, there was 99% adherence to that strategy. In the "favor chlorthalidone" group, chlorthalidone comprised 77% of new thiazide starts, up from 1% in the pre-study period. When the assigned strategy was followed, dosing in the recommended range was 48% for hydrochlorothiazide (25-50 mg/day) and 100% for chlorthalidone (12.5-25.0 mg/day). Providers were motivated to participate by a desire to contribute to a comparative effectiveness study. A study promotional mug, provider information letter, and interactions with the site investigator were identified as most helpful in reminding providers of their study drug strategy. Providers prescribed according to an assigned drug-choice strategy most of the time for the purpose of a comparative effectiveness study. This simple design could facilitate research participation and behavior change in non-research clinicians. Waiver of patient consent can broaden the representation of patients, providers, and settings.

Inactivation of the Na-Cl co-transporter (NCC) gene is associated with high BMD through both renal and bone mechanisms: analysis of patients with Gitelman syndrome and Ncc null mice.

PubMed

Nicolet-Barousse, Laurence; Blanchard, Anne; Roux, Christian; Pietri, Laurence; Bloch-Faure, May; Kolta, Sami; Chappard, Christine; Geoffroy, Valérie; Morieux, Caroline; Jeunemaitre, Xavier; Shull, Gary E; Meneton, Pierre; Paillard, Michel; Houillier, Pascal; De Vernejoul, Marie-Christine

2005-05-01

Chronic thiazide treatment is associated with high BMD. We report that patients and mice with null mutations in the thiazide-sensitive NaCl cotransporter (NCC) have higher renal tubular Ca reabsorption, higher BMD, and lower bone remodeling than controls, as well as abnormalities in Ca metabolism, mainly caused by Mg depletion. Chronic thiazide treatment decreases urinary Ca excretion (UVCa) and increases BMD. To understand the underlying mechanisms, Ca and bone metabolism were studied in two models of genetic inactivation of the thiazide-sensitive NaCl cotransporter (NCC): patients with Gitelman syndrome (GS) and Ncc knockout (Ncc(-/-)) mice. Ca metabolism was analyzed in GS patients and Ncc(-/-) mice under conditions of low dietary Ca. BMD was measured by DXA in patients and mice, and bone histomorphometry was analyzed in mice. GS patients had low plasma Mg. They exhibited reduced UVCa, but similar serum Ca and GFR as control subjects, suggesting increased renal Ca reabsorption. Blood PTH was lower despite lower serum ionized Ca, and Mg repletion almost corrected both relative hypoparathyroidism and low UVCa. BMD was significantly increased in GS patients at both lumbar (+7%) and femoral (+16%) sites, and osteocalcin was reduced. In Ncc(-/-) mice, serum Ca and GFR were unchanged, but UVCa was reduced and PTH was elevated; Mg repletion largely corrected both abnormalities. Trabecular and cortical BMD were higher than in Ncc(+/+) mice (+4% and +5%, respectively), and despite elevated PTH, were associated with higher cortical thickness and lower endosteal osteoclastic surface. Higher BMD is observed in GS patients and Ncc(-/-) mice. Relative hypoparathyroidism (human) and bone resistance to PTH (mice), mainly caused by Mg depletion, can explain the low bone remodeling and normal/low serum Ca despite increased renal Ca reabsorption.

Central nervous system considerations in the use of beta-blockers, angiotensin-converting enzyme inhibitors, and thiazide diuretics in managing essential hypertension.

PubMed

Gengo, F M; Gabos, C

1988-07-01

The most common mild side effects occurring with use of beta-blockers, thiazide diuretics, and angiotensin-converting enzyme inhibitors for blood pressure control are central nervous system symptoms, specifically lethargy, sedation, and fatigue. These symptoms affect 5% to 10% of patients taking these drugs. The mechanism by which beta-blockers may induce central nervous system effects is uncertain. Relative lipophilicity as a factor affecting penetrance of the blood-brain barrier has not proved to be a reliable predictor of whether the drug will cause such disturbances. Comparisons of atenolol (hydrophilic) and metoprolol (lipophilic) have shown no differences between these drugs with respect to side effects of the central nervous system. The incidence of central nervous system effects with angiotensin-converting enzyme inhibitors is similar to that for most beta-blockers. The precise role of the angiotensin-converting enzyme in the central nervous system is not well defined. Most thiazide diuretics are not associated with major complications of the central nervous system, although electrolyte imbalance may occasionally lead to complaints of neurologic symptoms. Because the incidence of central nervous system effects with these three classes of drugs is so low, concern for the side effects of the central nervous system is not a prime consideration in the choice of an initial antihypertensive agent.

[All diuretics used in the treatment of hypertension are not the same].

PubMed

Asil, Serkan; Atalar, Enver

2017-01-01

Diuretics have been used for years to treat hypertension as both a monotherapy and in combination. Hydrochlorothiazide, indapamide, and chlorthalidone have frequently been considered in the same category as thiazide diuretics, but there is no evidence that their activities are similar. Studies have shown that chlorthalidone and indapamide reduce cardiovascular morbidity and mortality; however, there is no study indicating that hydrochlorothiazide has beneficial effects on cardiovascular outcomes such as myocardial infarction, renal failure, stroke, or death. Hydrochlorothiazide has less effect on blood pressure, a high risk of metabolic side effects, and may not have pleiotropic effects. As a result, it is not accurate to evaluate chlorthalidone and indapamide as similar to thiazide diuretics. Indapamide or chlorthalidone is a better choice of diuretic for use in the treatment of hypertension.

Mechanisms and pharmacogenetic signals underlying thiazide diuretics blood pressure response

PubMed Central

Shahin, Mohamed H; Johnson, Julie A

2016-01-01

Thiazide (TZD) diuretics are among the most commonly prescribed antihypertensives globally; however their chronic blood pressure (BP) lowering mechanism remains unclear. Herein we discuss the current evidence regarding specific mechanisms regulating the antihypertensive effects of TZDs, suggesting that TZDs act via multiple complex and interacting mechanisms, including natriuresis with short term use and direct vasodilatory effects chronically. Additionally, we review pharmacogenomics signals that have been associated with TZDs BP-response in several cohorts (i.e. NEDD4L, PRKCA, EDNRA-GNAS, and YEATS4) and discuss how these genes might be related to TZD BP-response mechanism. Understanding the association between these genes and TZD BP mechanism might facilitate the development of new drugs and therapeutic approaches based on a deeper understanding of the determinants of BP-response. PMID:26874237

Doxercalciferol Injection

MedlinePlus

... injection is in a class of medications called vitamin D analogs. It works by helping the body to ... thiazide diuretics (''water pills''), or other forms of vitamin D. You and your caregiver should know that many ...

Effect of indapamide on urinary calcium excretion in patients with and without urinary stone disease.

PubMed

Ceylan, Kadir; Topal, Cevat; Erkoc, Reha; Sayarlioglu, Hayriye; Can, Saban; Yilmaz, Yuksel; Dogan, Ekrem; Algun, Ekrem; Gonulalan, Hasan

2005-06-01

Indapamide is an antihypertensive agent similar to thiazides, but with some different effects. Thiazide and thiazide-like diuretics are useful in preventing recurrent urinary stone formation due to their hypocalciuric effects. To determine the hypocalciuric and other effects on certain laboratory parameters of indapamide 1.5 mg in different patient groups. Four groups of patients recruited from urology and nephrology outpatient departments were experiencing non-hypercalciuric urinary stone disease (group 1), idiopathic hypercalciuria (group 2), urinary stone disease with hypercalciuria (group 3), and essential hypertension (group 4). In all patients, fasting serum uric acid, calcium, sodium, potassium, cholesterol, triglyceride, parathyroid hormone (PTH) values, and morning second-spot urine calcium and creatinine levels were assessed before and 8 weeks after treatment with indapamide. Urinary calcium excretion was reduced significantly in all groups: group 1 from 0.10 +/- 0.02 to 0.07 +/- 0.03 (mean +/-SD; 30% reduction; p < 0.001), group 2 from 0.30 +/- 0.15 to 0.15 +/- 0.10 (50% reduction; p < 0.001), group 3 from 0.35 +/- 0.15 to 0.20 +/- 0.10 (43% reduction; p < 0.001), and group 4 from 0.10 +/- 0.03 to 0.08 +/- 0.02 (20% reduction; p < 0.0010). These results should be interpreted with caution since no control group was included in this study. Mean serum uric acid and triglyceride levels were significantly increased, and mean PTH and potassium levels and diastolic and systolic blood pressure were significantly decreased in all groups. Few temporary adverse effects, such as dizziness and fatigue, were noticed and none of them caused discontinuation of treatment. Indapamide 1.5 mg/day is effective in decreasing calciuria in patients with non-hypercalciuric urinary stone disease, idiopathic hypercalciuria, urinary stone disease with hypercalciuria, and essential hypertension. This could be achieved with few adverse effects similar to those of thiazides and indapamide 2.5 mg. Indapamide decreased the PTH levels in all groups. Long-term clinical benefits of these effects should be evaluated prospectively with further randomized studies.

Mechanisms and pharmacogenetic signals underlying thiazide diuretics blood pressure response.

PubMed

Shahin, Mohamed H; Johnson, Julie A

2016-04-01

Thiazide (TZD) diuretics are among the most commonly prescribed antihypertensives globally; however their chronic blood pressure (BP) lowering mechanism remains unclear. Herein we discuss the current evidence regarding specific mechanisms regulating the antihypertensive effects of TZDs, suggesting that TZDs act via multiple complex and interacting mechanisms, including natriuresis with short term use and direct vasodilatory effects chronically. Additionally, we review pharmacogenomics signals that have been associated with TZDs BP-response in several cohorts (i.e. NEDD4L, PRKCA, EDNRA-GNAS, and YEATS4) and discuss how these genes might be related to TZD BP-response mechanism. Understanding the association between these genes and TZD BP mechanism might facilitate the development of new drugs and therapeutic approaches based on a deeper understanding of the determinants of BP-response. Copyright © 2016. Published by Elsevier Ltd.

Integrated compensatory network is activated in the absence of NCC phosphorylation.

PubMed

Grimm, P Richard; Lazo-Fernandez, Yoskaly; Delpire, Eric; Wall, Susan M; Dorsey, Susan G; Weinman, Edward J; Coleman, Richard; Wade, James B; Welling, Paul A

2015-05-01

Thiazide diuretics are used to treat hypertension; however, compensatory processes in the kidney can limit antihypertensive responses to this class of drugs. Here, we evaluated compensatory pathways in SPAK kinase-deficient mice, which are unable to activate the thiazide-sensitive sodium chloride cotransporter NCC (encoded by Slc12a3). Global transcriptional profiling, combined with biochemical, cell biological, and physiological phenotyping, identified the gene expression signature of the response and revealed how it establishes an adaptive physiology. Salt reabsorption pathways were created by the coordinate induction of a multigene transport system, involving solute carriers (encoded by Slc26a4, Slc4a8, and Slc4a9), carbonic anhydrase isoforms, and V-type H⁺-ATPase subunits in pendrin-positive intercalated cells (PP-ICs) and ENaC subunits in principal cells (PCs). A distal nephron remodeling process and induction of jagged 1/NOTCH signaling, which expands the cortical connecting tubule with PCs and replaces acid-secreting α-ICs with PP-ICs, were partly responsible for the compensation. Salt reabsorption was also activated by induction of an α-ketoglutarate (α-KG) paracrine signaling system. Coordinate regulation of a multigene α-KG synthesis and transport pathway resulted in α-KG secretion into pro-urine, as the α-KG-activated GPCR (Oxgr1) increased on the PP-IC apical surface, allowing paracrine delivery of α-KG to stimulate salt transport. Identification of the integrated compensatory NaCl reabsorption mechanisms provides insight into thiazide diuretic efficacy.

Integrated compensatory network is activated in the absence of NCC phosphorylation

PubMed Central

Grimm, P. Richard; Lazo-Fernandez, Yoskaly; Delpire, Eric; Wall, Susan M.; Dorsey, Susan G.; Weinman, Edward J.; Coleman, Richard; Wade, James B.; Welling, Paul A.

2015-01-01

Thiazide diuretics are used to treat hypertension; however, compensatory processes in the kidney can limit antihypertensive responses to this class of drugs. Here, we evaluated compensatory pathways in SPAK kinase–deficient mice, which are unable to activate the thiazide-sensitive sodium chloride cotransporter NCC (encoded by Slc12a3). Global transcriptional profiling, combined with biochemical, cell biological, and physiological phenotyping, identified the gene expression signature of the response and revealed how it establishes an adaptive physiology. Salt reabsorption pathways were created by the coordinate induction of a multigene transport system, involving solute carriers (encoded by Slc26a4, Slc4a8, and Slc4a9), carbonic anhydrase isoforms, and V-type H+-ATPase subunits in pendrin-positive intercalated cells (PP-ICs) and ENaC subunits in principal cells (PCs). A distal nephron remodeling process and induction of jagged 1/NOTCH signaling, which expands the cortical connecting tubule with PCs and replaces acid-secreting α-ICs with PP-ICs, were partly responsible for the compensation. Salt reabsorption was also activated by induction of an α-ketoglutarate (α-KG) paracrine signaling system. Coordinate regulation of a multigene α-KG synthesis and transport pathway resulted in α-KG secretion into pro-urine, as the α-KG–activated GPCR (Oxgr1) increased on the PP-IC apical surface, allowing paracrine delivery of α-KG to stimulate salt transport. Identification of the integrated compensatory NaCl reabsorption mechanisms provides insight into thiazide diuretic efficacy. PMID:25893600

Fixed-dose combinations in the management of hypertension: defining the place of angiotensin receptor antagonists and hydrochlorothiazide.

PubMed

Kjeldsen, Sverre E; Os, Ingrid; Høieggen, Aud; Beckey, Kim; Gleim, Gilbert W; Oparil, Suzanne

2005-01-01

We discuss combination therapy with angiotensin receptor antagonists (angiotensin receptor blockers; ARBs) and thiazide diuretics in light of the independent actions of both types of agents, and the adverse effects of both agents independently and in the context of the physiologic synergy achieved in using these agents together. ARBs counteract many of the adverse events associated with the use of thiazide diuretics and have been shown to reduce the occurrence of new-onset diabetes mellitus. We also review outcome trials in patients with hypertension (such as LIFE [Losartan Intervention For Endpoint reduction in hypertension], VALUE [Valsartan Antihypertensive Long-term Use Evaluation], and SCOPE [Study on COgnition and Prognosis in the Elderly]), in which losartan, valsartan, and candesartan cilexetil were used in combination with hydrochlorothiazide. Fixed combination ARB/hydrochlorothiazide agents make sense as initial therapy for patients in whom BP is >20/10 mm Hg above goal.

Why Your Mother Was Right: How Potassium Intake Reduces Blood Pressure.

PubMed

Ellison, David H; Terker, Andrew S

2015-01-01

Low potassium intake, common in western diets, increases blood pressure and enhances salt-sensitivity. Most humans in "Westernized" countries also consume excess salt. In studies using mice, we found that a high-salt, low-potassium diet activates the thiazide-sensitive Na-Cl cotransporter in the kidney. This effect led to sodium retention and increased blood pressure, and was dependent on plasma potassium. We postulated that this effect was mediated by changes in intracellular chloride caused by changes in membrane voltage. We developed a model in cultured cells permitting us to confirm this hypothesis. We then confirmed, using urinary exosomes, that dietary changes in normal humans, affect the thiazide-sensitive Na-Cl cotransporter in the same way. These data show that dietary potassium deficiency increases blood pressure largely by stimulating salt reabsorption along the distal nephron. They suggest that global efforts should focus on increasing potassium intake, which will attenuate the effects of high-salt diets.

What role does African ancestry play in how hypertensive patients respond to certain antihypertensive drug therapy?

PubMed

Seedat, Yackoob K; Brewster, Lizzy M

2014-02-01

This article is a summary of the response of the four commonly used antihypertensive agents in African ancestry patients. They are thiazide like diuretics or indapamide, calcium channel blockers (CCB), angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers, and β-adrenergic blockers (ARB). Response was superior in African ancestry patients on a thiazide like diuretic or indapamide and CCB, while the response to β-adrenergic blockers and ACEI are attenuated. Available data are very limited but self-defined ancestry seems to be the best predictor of individual responses to antihypertensive drugs. Knowledge of the factors like economic and social consideration affect the lower rate of detection, treatment and control of hypertension in the African ancestry population of the USA. For regions in which health care resources are particularly scarce, investment in population-based primary prevention strategies may yield the largest benefit.

The association between drugs frequently used by the elderly and vitamin D blood levels: a review of observational and experimental studies.

PubMed

van Orten-Luiten, Anne Claire B; Janse, André; Dhonukshe-Rutten, Rosalie A M; Witkamp, Renger F

2014-02-01

The risk of adverse drug reactions (ADRs) rises with increasing age. In the field of ADRs, drug-nutrient interactions (DNIs) are a relatively unexplored area. More knowledge will contribute to the simple prevention of this type of ADR. As the prevalence of vitamin D deficiency in the elderly is high, the primary objective of this review is to evaluate the literature on the relationship between drug use and vitamin D status, focusing on medicines commonly used by the elderly. PubMed was searched for human epidemiological and clinical studies published until early 2013, investigating the relationship between vitamin D blood levels and use of drugs from one of the following groups: proton pump inhibitors (PPIs), biguanides, vitamin K antagonists, platelet aggregation inhibitors, thiazide diuretics, loop diuretics, beta-blocking agents, calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors, angiotensin-II antagonists, statins, benzodiazepines, and antidepressants. A total of 63 publications were identified. Thiazide diuretics, statins, and calcium channel blocking agents were the most frequently studied drug groups. Associations between thiazides and vitamin D were mixed (n = 22), statins had no or positive associations (n = 16) and calcium blockers were not associated or were negatively associated with vitamin D (n = 10). In conclusion, several knowledge gaps exist on the relationship between drug use and vitamin D blood levels. Available data are scarce (particularly for the aged), study characteristics are highly variable, and found associations may be confounded by, amongst other things, the underlying disease. Nonetheless, this review provides a basis for future research on ADRs that contribute to nutrient deficiencies.

An association of losartan-hydrochlorothiazide, but not losartan-furosemide, completely arrests progressive injury in the remnant kidney.

PubMed

Arias, Simone Costa Alarcon; Souza, Renata Alves; Malheiros, Denise Maria Avancini Costa; Fanelli, Camilla; Fujihara, Clarice Kazue; Zatz, Roberto

2016-01-15

We have previously shown that an association of losartan and hydrochlorothiazide, initiated 1 mo after 5/6 nephrectomy (Nx), reversed hypertension and albuminuria and promoted lasting renoprotection. In this new study, we investigated whether equal or even better protection could be obtained by combining losartan and furosemide. Nx was performed in 58 Munich-Wistar rats. One month later, tail-cuff pressure and albuminuria were markedly elevated. At this time, Nx rats were distributed among the following four groups: untreated Nx rats, Nx rats that received losartan, Nx rats that received losartan + hydrochlorothiazide, and Nx rats that received losartan + furosemide. Seven months later, Nx rats exhibited high mortality, severe hypertension, albuminuria, glomerulosclerosis, and interstitial fibrosis. Losartan treatment limited mortality and attenuated the renal and hemodynamic abnormalities associated with Nx. As previously shown, the losartan + hydrochlorothiazide association normalized tail-cuff pressure and albumin, prevented renal injury, and reduced mortality to zero. The losartan + furosemide treatment failed to reduce tail-cuff pressure or albumin to normal and prevented renal injury less efficiently than the losartan and hydrochlorothiazide regimen. The reasons for the differing efficacies of the losartan + furosemide and losartan + hydrochlorothiazide schemes are unclear and may include beneficial nondiuretic actions of thiazides, such as vasorelaxation and antiproliferative activity. These results refute the established concept that thiazides and thiazide-like diuretics are ineffective at advanced chronic kidney disease stages. Rather, they suggest that, in view of their renoprotective action, these compounds may even be preferable to loop diuretics in the management of hypertension in advanced chronic kidney disease. Copyright © 2016 the American Physiological Society.

Thiazide overdose

MedlinePlus

... you have any questions about poisoning or poison control. It does NOT need to be an emergency. You can call for any reason, 24 hours a day, 7 days a week. What to Expect at the Emergency Room Take the container with you to the hospital, ...

A urate gene-by-diuretic interaction and gout risk in participants with hypertension: results from the ARIC study.

PubMed

McAdams-DeMarco, Mara A; Maynard, Janet W; Baer, Alan N; Kao, Linda W; Kottgen, Anna; Coresh, Josef

2013-05-01

To test for a urate gene-by-diuretic interaction on incident gout. The Atherosclerosis Risk in Communities Study is a prospective population-based cohort of 15 792 participants recruited from four US communities (1987-1989). Participants with hypertension and available single nucleotide polymorphism (SNP) genotype data were included. A genetic urate score (GUS) was created from common urate-associated SNPs for eight genes. Gout incidence was self-reported. Using logistic regression, the authors estimated the adjusted OR of incident gout by diuretic use, stratified by GUS median. Of 3524 participants with hypertension, 33% used a diuretic and 3.1% developed gout. The highest 9-year cumulative incidence of gout was in those with GUS above the median and taking a thiazide or loop diuretic (6.3%). Compared with no thiazide or loop diuretic use, their use was associated with an OR of 0.40 (95% CI 0.14 to 1.15) among those with a GUS below the median and 2.13 (95% CI 1.23 to 3.67) for those with GUS above the median; interaction p=0.006. When investigating the genes separately, SLC22A11 and SLC2A9 showed a significant interaction, consistent with the former encoding an organic anion/dicarboxylate exchanger, which mediates diuretic transport in the kidney. Participants who were genetically predisposed to hyperuricaemia were susceptible to developing gout when taking thiazide or loop diuretics, an effect not evident among those without a genetic predisposition. These findings argue for a potential benefit of genotyping individuals with hypertension to assess gout risk, relative in part to diuretic use.

A urate gene-by-diuretic interaction and gout risk in participants with hypertension: results from the ARIC study

PubMed Central

McAdams-DeMarco, Mara A; Maynard, Janet W; Baer, Alan N; Kao, Linda W; Kottgen, Anna; Coresh, Josef

2015-01-01

Objective To test for a urate gene-by-diuretic interaction on incident gout. Methods The Atherosclerosis Risk in Communities Study is a prospective population-based cohort of 15 792 participants recruited from four US communities (1987–1989). Participants with hypertension and available single nucleotide polymorphism (SNP) genotype data were included. A genetic urate score (GUS) was created from common urate-associated SNPs for eight genes. Gout incidence was self-reported. Using logistic regression, the authors estimated the adjusted OR of incident gout by diuretic use, stratified by GUS median. Results Of 3524 participants with hypertension, 33% used a diuretic and 3.1% developed gout. The highest 9-year cumulative incidence of gout was in those with GUS above the median and taking a thiazide or loop diuretic (6.3%). Compared with no thiazide or loop diuretic use, their use was associated with an OR of 0.40 (95% CI 0.14 to 1.15) among those with a GUS below the median and 2.13 (95% CI 1.23 to 3.67) for those with GUS above the median; interaction p=0.006. When investigating the genes separately, SLC22A11 and SLC2A9 showed a significant interaction, consistent with the former encoding an organic anion/dicarboxylate exchanger, which mediates diuretic transport in the kidney. Conclusions Participants who were genetically predisposed to hyperuricaemia were susceptible to developing gout when taking thiazide or loop diuretics, an effect not evident among those without a genetic predisposition. These findings argue for a potential benefit of genotyping individuals with hypertension to assess gout risk, relative in part to diuretic use. PMID:22753387

The Thiazide-sensitive NaCl Cotransporter Is Targeted for Chaperone-dependent Endoplasmic Reticulum-associated Degradation*

PubMed Central

Needham, Patrick G.; Mikoluk, Kasia; Dhakarwal, Pradeep; Khadem, Shaheen; Snyder, Avin C.; Subramanya, Arohan R.; Brodsky, Jeffrey L.

2011-01-01

The thiazide-sensitive NaCl cotransporter (NCC, SLC12A3) mediates salt reabsorption in the distal nephron of the kidney and is the target of thiazide diuretics, which are commonly prescribed to treat hypertension. Mutations in NCC also give rise to Gitelman syndrome, a hereditary salt-wasting disorder thought in most cases to arise from impaired NCC biogenesis through enhanced endoplasmic reticulum-associated degradation (ERAD). Because the machinery that mediates NCC quality control is completely undefined, we employed yeast as a model heterologous expression system to identify factors involved in NCC degradation. We confirmed that NCC was a bona fide ERAD substrate in yeast, as the majority of NCC polypeptide was integrated into ER membranes, and its turnover rate was sensitive to proteasome inhibition. NCC degradation was primarily dependent on the ER membrane-associated E3 ubiquitin ligase Hrd1. Whereas several ER luminal chaperones were dispensable for NCC ERAD, NCC ubiquitination and degradation required the activity of Ssa1, a cytoplasmic Hsp70 chaperone. Compatible findings were observed when NCC was expressed in mammalian kidney cells, as the cotransporter was polyubiquitinated and degraded by the proteasome, and mammalian cytoplasmic Hsp70 (Hsp72) coexpression stimulated the degradation of newly synthesized NCC. Hsp70 also preferentially associated with the ER-localized NCC glycosylated species, indicating that cytoplasmic Hsp70 plays a critical role in selecting immature forms of NCC for ERAD. Together, these results provide the first survey of components involved in the ERAD of a mammalian SLC12 cation chloride cotransporter and provide a framework for future studies on NCC ER quality control. PMID:22027832

Functional assessment of sodium chloride cotransporter NCC mutants in polarized mammalian epithelial cells.

PubMed

Rosenbaek, Lena L; Rizzo, Federica; MacAulay, Nanna; Staub, Olivier; Fenton, Robert A

2017-08-01

The thiazide-sensitive sodium chloride cotransporter NCC is important for maintaining serum sodium (Na + ) and, indirectly, serum potassium (K + ) levels. Functional studies on NCC have used cell lines with native NCC expression, transiently transfected nonpolarized cell lines, or Xenopus laevis oocytes. Here, we developed the use of polarized Madin-Darby canine kidney type I (MDCKI) mammalian epithelial cell lines with tetracycline-inducible human NCC expression to study NCC activity and membrane abundance in the same system. In radiotracer assays, induced cells grown on filters had robust thiazide-sensitive and chloride dependent sodium-22 ( 22 Na) uptake from the apical side. To minimize cost and maximize throughput, assays were modified to use cells grown on plastic. On plastic, cells had similar thiazide-sensitive 22 Na uptakes that increased following preincubation of cells in chloride-free solutions. NCC was detected in the plasma membrane, and both membrane abundance and phosphorylation of NCC were increased by incubation in chloride-free solutions. Furthermore, in cells exposed for 15 min to low or high extracellular K + , the levels of phosphorylated NCC increased and decreased, respectively. To demonstrate that the system allows rapid and systematic assessment of mutated NCC, three phosphorylation sites in NCC were mutated, and NCC activity was examined. 22 Na fluxes in phosphorylation-deficient mutants were reduced to baseline levels, whereas phosphorylation-mimicking mutants were constitutively active, even without chloride-free stimulation. In conclusion, this system allows the activity, cellular localization, and abundance of wild-type or mutant NCC to be examined in the same polarized mammalian expression system in a rapid, easy, and low-cost fashion. Copyright © 2017 the American Physiological Society.

Thiazides diuretics in the treatment of nephrolithiasis: are we using them in an evidence-based fashion?

PubMed

Vigen, Rebecca; Weideman, Rick A; Reilly, Robert F

2011-09-01

In the 1980s a change occurred in hydrochlorothiazide prescribing practices for hypertension from high-dose (50 mg/day) to low-dose (12.5-25 mg/day) therapy. However, randomized controlled trials (RCT) for prevention of calcium-containing kidney stones (CCKS) employed only high doses (≥ 50 mg/day). We hypothesized that these practices have resulted in underdosing of hydrochlorothiazide for prevention of CCKS. Patients with a filled prescription for thiazide diuretics that underwent a 24-h urine stone risk factor analysis were eligible. Those with evidence that thiazide was prescribed for CCKS were further analyzed. Of 107 patients, 102 were treated with hydrochlorothiazide, 4 with indapamide, and one with chlorthalidone. Only 35% of hydrochlorothiazide-treated patients received 50 mg/day; a dose previously shown to reduce stone recurrence. Fifty-two percent were prescribed 25 mg and 13% 12.5 mg daily, doses that were not studied in RCT. Evidence-based hydrochlorothiazide use was suboptimal regardless of where the patient received care (Nephrology or Endocrinology clinic). In a small subset of patients (n = 6) with 24-h urinary calcium excretion measured at baseline and after 2 hydrochlorothiazide doses (25 and ≥ 50 mg), there was a trend toward decreased urinary calcium excretion as the dose was increased from 25 to ≥ 50 mg/day (p = 0.051). Low-dose hydrochlorothiazide was often used for prevention of CCKS despite the fact that there is no evidence that it is effective in this setting. This may have resulted from a practice pattern of using lower doses for hypertension therapy or a lack of knowledge of RCT results in treatment of CCKS.

Double Knockout of the Na+-Driven Cl-/HCO3- Exchanger and Na+/Cl- Cotransporter Induces Hypokalemia and Volume Depletion.

PubMed

Sinning, Anne; Radionov, Nikita; Trepiccione, Francesco; López-Cayuqueo, Karen I; Jayat, Maximilien; Baron, Stéphanie; Cornière, Nicolas; Alexander, R Todd; Hadchouel, Juliette; Eladari, Dominique; Hübner, Christian A; Chambrey, Régine

2017-01-01

We recently described a novel thiazide-sensitive electroneutral NaCl transport mechanism resulting from the parallel operation of the Cl - /HCO 3 - exchanger pendrin and the Na + -driven Cl - /2HCO 3 - exchanger (NDCBE) in β-intercalated cells of the collecting duct. Although a role for pendrin in maintaining Na + balance, intravascular volume, and BP is well supported, there is no in vivo evidence for the role of NDCBE in maintaining Na + balance. Here, we show that deletion of NDCBE in mice caused only subtle perturbations of Na + homeostasis and provide evidence that the Na + /Cl - cotransporter (NCC) compensated for the inactivation of NDCBE. To unmask the role of NDCBE, we generated Ndcbe/Ncc double-knockout (dKO) mice. On a normal salt diet, dKO and single-knockout mice exhibited similar activation of the renin-angiotensin-aldosterone system, whereas only dKO mice displayed a lower blood K + concentration. Furthermore, dKO mice displayed upregulation of the epithelial sodium channel (ENaC) and the Ca 2+ -activated K + channel BKCa. During NaCl depletion, only dKO mice developed marked intravascular volume contraction, despite dramatically increased renin activity. Notably, the increase in aldosterone levels expected on NaCl depletion was attenuated in dKO mice, and single-knockout and dKO mice had similar blood K + concentrations under this condition. In conclusion, NDCBE is necessary for maintaining sodium balance and intravascular volume during salt depletion or NCC inactivation in mice. Furthermore, NDCBE has an important role in the prevention of hypokalemia. Because NCC and NDCBE are both thiazide targets, the combined inhibition of NCC and the NDCBE/pendrin system may explain thiazide-induced hypokalemia in some patients. Copyright © 2016 by the American Society of Nephrology.

Metabolic complications associated with use of diuretics.

PubMed

Palmer, Biff F

2011-11-01

Diuretics are commonly used therapeutic agents that act to inhibit sodium transport systems along the length of the renal tubule. The most effective diuretics are inhibitors of sodium chloride transport in the thick ascending limb of Henle. Loop diuretics mobilize large amounts of sodium chloride and water and produce a copious diuresis with a sharp reduction of extracellular fluid volume. As the site of action of diuretics moves downstream (thiazide and potassium-sparing diuretics), their effectiveness declines because the transport systems they inhibit have low transport capacity. Depending on the site of action diuretics can influence the renal handling of electrolyte-free water, calcium, potassium, protons, sodium bicarbonate, and uric acid. As a result, electrolyte and acid-base disorders commonly accompany diuretic use. Glucose and lipid abnormalities also can occur, particularly with the use of thiazide diuretics. This review focuses on the biochemical complications associated with the use of diuretics. The development of these complications can be minimized with careful monitoring, dosage adjustment, and replacement of electrolyte losses. Copyright © 2011 Elsevier Inc. All rights reserved.

Diuretics in the treatment of hypertension. Part 2: loop diuretics and potassium-sparing agents.

PubMed

Tamargo, Juan; Segura, Julian; Ruilope, Luis M

2014-04-01

Diuretics enhance the renal excretion of Na(+) and water due to a direct action at different tubular sites of the nephron where solute re-absorption occurs. This paper focuses on the mechanism of action, pharmacodynamics, antihypertensive effects, adverse effects, interactions and contraindications of loop diuretics and potassium-sparing agents (including mineralocorticoid receptor antagonists (MRAs) and epithelial Na(+) channel blockers). Loop diuretics are less effective than thiazide diuretics in lowering blood pressure, so that their major use is in edematous patients with congestive heart failure (HF), cirrhosis with ascites and nephritic edema. MRAs represent a major advance in the treatment of resistant hypertension, primary and secondary hyperaldosteronism and in patients with systolic HF to reduce the risks of hospitalization and of premature death. Potassium-sparing diuretics when coadministered with diuretics (thiazides and loop diuretics) working at more proximal nephron locations reduce the risk of hypokalemia and hypomagnesemia and the risk of cardiac arrhythmias. At the end of the article, the basis for the combination of diuretics with other antihypertensive drugs to achieve blood pressure targets is presented.

Decongestion: Diuretics and other therapies for hospitalized heart failure

PubMed Central

Vazir, Ali; Cowie, Martin R.

2016-01-01

Acute heart failure (AHF) is a potentially life-threatening clinical syndrome, usually requiring hospital admission. Often the syndrome is characterized by congestion, and is associated with long hospital admissions and high risk of readmission and further healthcare expenditure. Despite a limited evidence-base, diuretics remain the first-line treatment for congestion. Loop diuretics are typically the first-line diuretic strategy with some evidence that initial treatment with continuous infusion or boluses of high-dose loop diuretic is superior to an initial lower dose strategy. In patients who have impaired responsiveness to diuretics, the addition of an oral thiazide or thiazide-like diuretic to induce sequential nephron blockade can be beneficial. The use of intravenous low-dose dopamine is no longer supported in heart failure patients with preserved systolic blood pressure and its use to assist diuresis in patients with low systolic blood pressures requires further study. Mechanical ultrafiltration has been used to treat patients with heart failure and fluid retention, but the evidence-base is not robust, and its place in clinical practice is yet to be established. Several novel pharmacological agents remain under investigation. PMID:27056656

Drug-induced abnormalities of potassium metabolism.

PubMed

Kokot, Franciszek; Hyla-Klekot, Lidia

2008-01-01

Pharmacotherapy has progressed rapidly over the last 20 years with the result that general practioners more and more often use drugs which may influence potassium metabolism at the kidney or gastrointestinal level, or the transmembrane transport of potassium at the cellular level. Potassium abnormalities may result in life-theatening clinical conditions. Hypokalemia is most frequently caused by renal loss of this electrolyte (thiazide, thiazide-like and loop diuretics, glucocorticoids) and the gastrointestinal tract (laxatives, diarrhea, vomiting, external fistula), and may be the result of an increased intracellular potassium influx induced by sympathicomimetics used mostly by patients with asthma, or by insulin overdosage in diabetic subjects. The leading symptoms of hypokalemia are skeletal and smooth muscle weakness and cardiac arrhythmias. Hyperkalemia may be caused by acute or end-stage renal failure, impaired tubular excretion of potassium (blockers of the renin-angiotensin-aldosterone system, nonsteroidal anti-inflammatory drugs, cyclosporine, antifungal drugs, potassium sparing diuretics), acidemia, and severe cellular injury (tumor lysis syndrome). Hyperkalemia may be the cause of severe injury of both skeletal and smooth muscle cells. The specific treatment counteracting hyperkalemia is a bolus injection of calcium salts and, when necessary, hemodialysis.

Use of acetazolamide in lithium-induced nephrogenic diabetes insipidus: a case report.

PubMed

Macau, Ricardo A; da Silva, Tiago Nunes; Silva, Joana Rego; Ferreira, Ana Gonçalves; Bravo, Pedro

2018-01-01

Lithium-induced nephrogenic diabetes insipidus (Li-NDI) is a rare and difficult-to-treat condition. A study in mice and two recent papers describe the use of acetazolamide in Li-NDI in 7 patients (a case report and a 6 patient series). We describe the case of a 63-year-old woman with bipolar disorder treated with lithium and no previous history of diabetes insipidus. She was hospitalized due to a bowel obstruction and developed severe dehydration after surgery when she was water deprived. After desmopressin administration and unsuccessful thiazide and amiloride treatment, acetazolamide was administrated to control polyuria and hydroelectrolytic disorders without significant side effects. To our knowledge, this is the third publication on acetazolamide use in Li-NDI patients. Treatment of lithium-induced nephrogenic diabetes insipidus might be challenging.Vasopressin, amiloride and thiazide diuretics have been used in lithium-induced nephrogenic diabetes insipidus treatment.Acetazolamide might be an option to treat lithium-induced nephrogenic diabetes insipidus patients who fail to respond to standard treatment.The use of acetazolamide in lithium-induced nephrogenic diabetes insipidus must be monitored, including its effects on glomerular filtration rate.

Generic sample preparation combined with high-resolution liquid chromatography-time-of-flight mass spectrometry for unification of urine screening in doping-control laboratories.

PubMed

Peters, R J B; Oosterink, J E; Stolker, A A M; Georgakopoulos, C; Nielen, M W F

2010-04-01

A unification of doping-control screening procedures of prohibited small molecule substances--including stimulants, narcotics, steroids, beta2-agonists and diuretics--is highly urgent in order to free resources for new classes such as banned proteins. Conceptually this may be achieved by the use of a combination of one gas chromatography-time-of-flight mass spectrometry method and one liquid chromatography-time-of-flight mass spectrometry method. In this work a quantitative screening method using high-resolution liquid chromatography in combination with accurate-mass time-of-flight mass spectrometry was developed and validated for determination of glucocorticosteroids, beta2-agonists, thiazide diuretics, and narcotics and stimulants in urine. To enable the simultaneous isolation of all the compounds of interest and the necessary purification of the resulting extracts, a generic extraction and hydrolysis procedure was combined with a solid-phase extraction modified for these groups of compounds. All 56 compounds are determined using positive electrospray ionisation with the exception of the thiazide diuretics for which the best sensitivity was obtained by using negative electrospray ionisation. The results show that, with the exception of clenhexyl, procaterol, and reproterol, all compounds can be detected below the respective minimum required performance level and the results for linearity, repeatability, within-lab reproducibility, and accuracy show that the method can be used for quantitative screening. If qualitative screening is sufficient the instrumental analysis may be limited to positive ionisation, because all analytes including the thiazides can be detected at the respective minimum required levels in the positive mode. The results show that the application of accurate-mass time-of-flight mass spectrometry in combination with generic extraction and purification procedures is suitable for unification and expansion of the window of screening methods of doping laboratories. Moreover, the full-scan accurate-mass data sets obtained still allow retrospective examination for emerging doping agents, without re-analyzing the samples.

Antihypertensive medication classes used among medicare beneficiaries initiating treatment in 2007-2010.

PubMed

Kent, Shia T; Shimbo, Daichi; Huang, Lei; Diaz, Keith M; Kilgore, Meredith L; Oparil, Suzanne; Muntner, Paul

2014-01-01

After the 2003 publication of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) guidelines, there was a 5-10% increase in patients initiating antihypertensive medication with a thiazide-type diuretic, but most patients still did not initiate treatment with this class. There are few contemporary published data on antihypertensive medication classes filled by patients initiating treatment. We used the 5% random Medicare sample to study the initiation of antihypertensive medication between 2007 and 2010. Initiation was defined by the first antihypertensive medication fill preceded by 365 days with no antihypertensive medication fills. We restricted our analysis to beneficiaries ≥ 65 years who had two or more outpatient visits with a hypertension diagnosis and full Medicare fee-for-service coverage for the 365 days prior to initiation of antihypertensive medication. Between 2007 and 2010, 32,142 beneficiaries in the 5% Medicare sample initiated antihypertensive medication. Initiation with a thiazide-type diuretic decreased from 19.2% in 2007 to 17.9% in 2010. No other changes in medication classes initiated occurred over this period. Among those initiating antihypertensive medication in 2010, 31.3% filled angiotensin-converting enzyme inhibitors (ACE-Is), 26.9% filled beta blockers, 17.2% filled calcium channel blockers, and 14.4% filled angiotensin receptor blockers (ARBs). Initiation with >1 antihypertensive medication class decreased from 25.6% in 2007 to 24.1% in 2010. Patients initiated >1 antihypertensive medication class most commonly with a thiazide-type diuretic and either an ACE-I or ARB. These results suggest that JNC 7 had a limited long-term impact on the choice of antihypertensive medication class and provide baseline data prior to the publication of the 2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults from the Panel Members Appointed to the Eighth Joint National Committee (JNC 8).

Comparative effectiveness of antihypertensive therapeutic classes and treatment strategies in the initiation of therapy in primary care patients: a Distributed Ambulatory Research in Therapeutics Network (DARTNet) study.

PubMed

Bronsert, Michael R; Henderson, William G; Valuck, Robert; Hosokawa, Patrick; Hammermeister, Karl

2013-01-01

Few comparative effectiveness studies of treatment strategies using antihypertensive therapeutic classes in hypertension control have been assessed in a primary care environment. The objectives are to compare the effectiveness of common antihypertensive therapeutic classes initiated as monotherapy and of fixed-dose combinations (FDCs), free-equivalent combinations (FECs), and monotherapy on hypertension control. This article reports observational comparative effectiveness analyses of data electronically extracted from electronic health records. The study population consisted of 8,676 patients with an incident prescription for an antihypertensive agent of a total of 79,176 patients receiving antihypertensive therapy in 33 geographically diverse primary care clinics. The main measures were reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) and rates of attaining goals per the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7). There were small, clinically insignificant differences in blood pressure reductions between the monotherapy classes. Higher rates of blood pressure control were obtained when patients were initiated on an angiotensin-converting enzyme inhibitor than a thiazide or thiazide-like diuretic (47.8% vs 39.9%) or a β-blocker versus a thiazide (45.9% vs 39.9%). Patients initiated on FDCs had significantly larger reductions in blood pressure than patients initiated on FECs (-17.3 vs -12.0 mm Hg SBP; -10.1 vs -6.0 mm Hg DBP) or monotherapy (-17.3 vs -13.6 mm Hg SBP; -10.1 vs -7.9 mm Hg DBP). Rates of attaining JNC7 goals also were better for FDCs than FECs (57.2% vs 42.5%) and for FDCs versus monotherapy (57.2% vs 44.9%). Patients initiated on angiotensin-converting enzyme inhibitors and β-blockers had slightly higher rates of blood pressure control. The use of FDCs as initial therapy is more effective in the control of hypertension than monotherapy or FECs.

Choice of generic antihypertensive drugs for the primary prevention of cardiovascular disease--a cost-effectiveness analysis.

PubMed

Wisløff, Torbjørn; Selmer, Randi M; Halvorsen, Sigrun; Fretheim, Atle; Norheim, Ole F; Kristiansen, Ivar Sønbø

2012-04-04

Hypertension is one of the leading causes of cardiovascular disease (CVD). A range of antihypertensive drugs exists, and their prices vary widely mainly due to patent rights. The objective of this study was to explore the cost-effectiveness of different generic antihypertensive drugs as first, second and third choice for primary prevention of cardiovascular disease. We used the Norwegian Cardiovascular Disease model (NorCaD) to simulate the cardiovascular life of patients from hypertension without symptoms until they were all dead or 100 years old. The risk of CVD events and costs were based on recent Norwegian sources. In single-drug treatment, all antihypertensives are cost-effective compared to no drug treatment. In the base-case analysis, the first, second and third choice of antihypertensive were calcium channel blocker, thiazide and angiotensin-converting enzyme inhibitor. However the sensitivity and scenario analyses indicated considerable uncertainty in that angiotensin receptor blockers as well as, angiotensin-converting enzyme inhibitors, beta blockers and thiazides could be the most cost-effective antihypertensive drugs. Generic antihypertensives are cost-effective in a wide range of risk groups. There is considerable uncertainty, however, regarding which drug is the most cost-effective.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pruss, T.; Wolf, P.S.

Indapamide is a new indoline antihypertensive diuretic agent whose chemical structure differs substantially from those of the thiazides. The hydrophobic indoline moiety of indapamide confers a lipid solubility to the molecule that is 5 to 80 times greater than that of the thiazide diuretics. Thus indapamide accumulates in vascular smooth muscle at a concentration 10 times higher than that of protein-free perfusate. The affinity of indapamide for vascular smooth muscle manifests itself in vitro and in vivo as a decrease in reactivity following various pharmacologic interventions. Moreover, in vitro studies have demonstrated that indapamide decreases the inward calcium current andmore » the transmembrane influx of calcium. The diuretic effect of indapamide is predominantly due to inhibition of sodium reabsorption at the cortical diluting segment of the distal convoluted tubule. In animal studies, intravenous indapamide has no effect on glomerular filtration rate or renal blood flow. Indapamide is well absorbed and extensively metabolized in animals and humans, with biliary excretion being the predominant route of elimination in animals. Most important, repeat administration of indapamide to dogs with both kidneys removed produces no accumulation of intact indapamide or its metabolites. Extensive drug safety studies in animals indicate that indapamide produces no overt toxicity and exhibits a good margin of safety.« less

Decongestion: Diuretics and other therapies for hospitalized heart failure.

PubMed

Vazir, Ali; Cowie, Martin R

2016-04-01

Acute heart failure (AHF) is a potentially life-threatening clinical syndrome, usually requiring hospital admission. Often the syndrome is characterized by congestion, and is associated with long hospital admissions and high risk of readmission and further healthcare expenditure. Despite a limited evidence-base, diuretics remain the first-line treatment for congestion. Loop diuretics are typically the first-line diuretic strategy with some evidence that initial treatment with continuous infusion or boluses of high-dose loop diuretic is superior to an initial lower dose strategy. In patients who have impaired responsiveness to diuretics, the addition of an oral thiazide or thiazide-like diuretic to induce sequential nephron blockade can be beneficial. The use of intravenous low-dose dopamine is no longer supported in heart failure patients with preserved systolic blood pressure and its use to assist diuresis in patients with low systolic blood pressures requires further study. Mechanical ultrafiltration has been used to treat patients with heart failure and fluid retention, but the evidence-base is not robust, and its place in clinical practice is yet to be established. Several novel pharmacological agents remain under investigation. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Reversal of diuretic-associated impaired glucose tolerance and new-onset diabetes: results of the STAR-LET study.

PubMed

Bakris, George; Molitch, Mark; Zhou, Qian; Sarafidis, Pantelis; Champion, Annette; Bacher, Peter; Sowers, James R

2008-01-01

Reversal of new-onset diabetes secondary to thiazide diuretic use remains questionable. STAR-LET was a 6-month extension of the Study of Trandolapril/Verapamil SR and Insulin Resistance (STAR), which assessed the effects of a fixed-dose renin-angiotensin system inhibitor (RASI)/hydrochlorothiazide (HCTZ) combination on changes in 2-hour oral glucose tolerance test (OGTT) results. STAR-LET explored whether the glycemic impact of HCTZ could be reversed by conversion to a RASI/verapamil combination. The primary outcome was change in 2-hour OGTT results. Fifty-one percent of the STAR patients were enrolled in STAR-LET. The 2-hour OGTT value (mmol/L) was unchanged from STAR baseline in the RASI/verapamil group (7.7+/-2.4 vs 8.1+/-3.3; P=.18) and improved in those who were switched from RASI/HCTZ to RASI/verapamil (8.5+/-3.0 vs 7.2+/-2.3; P<.001). This exploratory study suggests that the impairment in glycemic control seen with use of a thiazide diuretic combined with a RASI can be reversed by switching to a regimen that does not include a diuretic.

Current trends in treatment of hypertension in Karachi and cost minimization possibilities.

PubMed

Hussain, Izhar M; Naqvi, Baqir S; Qasim, Rao M; Ali, Nasir

2015-01-01

This study finds out drug usage trends in Stage I Hypertensive Patients without any compelling indications in Karachi, deviations of current practices from evidence based antihypertensive therapeutic guidelines and looks for cost minimization opportunities. In the present study conducted during June 2012 to August 2012, two sets were used. Randomized stratified independent surveys were conducted in doctors and general population - including patients, using pretested questionnaires. Sample sizes for doctors and general population were 100 and 400 respectively. Statistical analysis was conducted on Statistical Package for Social Science (SPSS). Financial impact was also analyzed. On the basis of patients' doctors' feedback, Beta Blockers, and Angiotensin Converting Enzyme Inhibitors were used more frequently than other drugs. Thiazides and low-priced generics were hardly prescribed. Beta blockers were prescribed widely and considered cost effective. This trend increases cost by two to ten times. Feedbacks showed that therapeutic guidelines were not followed by the doctors practicing in the community and hospitals in Karachi. Thiazide diuretics were hardly used. Beta blockers were widely prescribed. High priced market leaders or expensive branded generics were commonly prescribed. Therefore, there are great opportunities for cost minimization by using evidence-based clinically effective and safe medicines.

Diuretics, calciuria and secondary hyperparathyroidism in the Chronic Renal Insufficiency Cohort.

PubMed

Isakova, Tamara; Anderson, Cheryl A M; Leonard, Mary B; Xie, Dawei; Gutiérrez, Orlando M; Rosen, Leigh K; Theurer, Jacquie; Bellovich, Keith; Steigerwalt, Susan P; Tang, Ignatius; Anderson, Amanda Hyre; Townsend, Raymond R; He, Jiang; Feldman, Harold I; Wolf, Myles

2011-04-01

Secondary hyperparathyroidism is a common complication of chronic kidney disease (CKD) that is associated with bone disease, cardiovascular disease and death. Pathophysiological factors that maintain secondary hyperparathyroidism in advanced CKD are well-known, but early mechanisms of the disease that can be targeted for its primary prevention are poorly understood. Diuretics are widely used to control volume status and blood pressure in CKD patients but are also known to have important effects on renal calcium handling, which we hypothesized could alter the risk of secondary hyperparathyroidism. We examined the relationship of diuretic treatment with urinary calcium excretion, parathyroid hormone (PTH) levels and prevalence of secondary hyperparathyroidism (PTH ≥ 65 pg/mL) in a cross-sectional study of 3616 CKD patients in the Chronic Renal Insufficiency Cohort. Compared with no diuretics, treatment with loop diuretics was independently associated with higher adjusted urinary calcium (55.0 versus 39.6 mg/day; P < 0.001), higher adjusted PTH [67.9, 95% confidence interval (CI) 65.2-70.7 pg/mL, versus 52.8, 95% CI 51.1-54.6 pg/mL, P < 0.001] and greater odds of secondary hyperparathyroidism (odds ratio 2.1; 95% CI 1.7-2.6). Thiazide monotherapy was associated with lower calciuria (25.5 versus 39.6 mg/day; P < 0.001) but only modestly lower PTH levels (50.0, 95% CI 47.8-52.3, versus 520.8, 95% CI 51.1-54.6 pg/mL, P = 0.04) compared with no diuretics. However, coadministration of thiazide and loop diuretics was associated with blunted urinary calcium (30.3 versus 55.0 mg/day; P <0.001) and odds of hyperparathyroidism (odds ratio 1.3 versus 2.1; P for interaction = 0.05) compared with loop diuretics alone. Loop diuretic use was associated with greater calciuria, PTH levels and odds of secondary hyperparathyroidism compared to no treatment. These associations were attenuated in patients who were coadministered thiazides. Diuretic choice is a potentially modifiable determinant of secondary hyperparathyroidism in CKD.

Comparison of single and combination diuretics on glucose tolerance (PATHWAY-3): protocol for a randomised double-blind trial in patients with essential hypertension

PubMed Central

Brown, Morris J; Williams, Bryan; MacDonald, Thomas M; Caulfield, Mark; Cruickshank, J Kennedy; McInnes, Gordon; Sever, Peter; Webb, David J; Salsbury, Jackie; Morant, Steve; Ford, Ian

2015-01-01

Introduction Thiazide diuretics are associated with increased risk of diabetes mellitus. This risk may arise from K+-depletion. We hypothesised that a K+-sparing diuretic will improve glucose tolerance, and that combination of low-dose thiazide with K+-sparing diuretic will improve both blood pressure reduction and glucose tolerance, compared to a high-dose thiazide. Methods and analysis This is a parallel-group, randomised, double-blind, multicentre trial, comparing hydrochlorothiazide 25–50 mg, amiloride 10–20 mg and combination of both diuretics at half these doses. A single-blind placebo run-in of 1 month is followed by 24 weeks of blinded active treatment. There is forced dose-doubling after 3 months. The Primary end point is the blood glucose 2 h after oral ingestion of a 75 g glucose drink (OGTT), following overnight fasting. The primary outcome is the difference between 2 h glucose at weeks 0, 12 and 24. Secondary outcomes include the changes in home systolic blood pressure (BP) and glycated haemoglobin and prediction of response by baseline plasma renin. Eligibility criteria are: age 18–79, systolic BP on permitted background treatment ≥140 mm Hg and home BP ≥130 mm Hg and one component of the metabolic syndrome additional to hypertension. Principal exclusions are diabetes, estimated-glomerular filtration rate <45 mL/min, abnormal plasma K+, clinic SBP >200 mm Hg or DBP >120 mm Hg (box 2). The sample size calculation indicates that 486 patients will give 80% power at α=0.01 to detect a difference in means of 1 mmol/L (SD=2.2) between 2 h glucose on hydrochlorothiazide and comparators. Ethics and dissemination PATHWAY-3 was approved by Cambridge South Ethics Committee, number 09/H035/19. The trial results will be published in a peer-reviewed scientific journal. Trial registration numbers Eudract number 2009-010068-41 and clinical trials registration number: NCT02351973. PMID:26253567

Diuretics, calciuria and secondary hyperparathyroidism in the Chronic Renal Insufficiency Cohort

PubMed Central

Isakova, Tamara; Anderson, Cheryl A. M.; Leonard, Mary B.; Xie, Dawei; Gutiérrez, Orlando M.; Rosen, Leigh K.; Theurer, Jacquie; Bellovich, Keith; Steigerwalt, Susan P.; Tang, Ignatius; Anderson, Amanda Hyre; Townsend, Raymond R.; He, Jiang; Feldman, Harold I.; Wolf, Myles

2011-01-01

Background. Secondary hyperparathyroidism is a common complication of chronic kidney disease (CKD) that is associated with bone disease, cardiovascular disease and death. Pathophysiological factors that maintain secondary hyperparathyroidism in advanced CKD are well-known, but early mechanisms of the disease that can be targeted for its primary prevention are poorly understood. Diuretics are widely used to control volume status and blood pressure in CKD patients but are also known to have important effects on renal calcium handling, which we hypothesized could alter the risk of secondary hyperparathyroidism. Methods. We examined the relationship of diuretic treatment with urinary calcium excretion, parathyroid hormone (PTH) levels and prevalence of secondary hyperparathyroidism (PTH ≥ 65 pg/mL) in a cross-sectional study of 3616 CKD patients in the Chronic Renal Insufficiency Cohort. Results. Compared with no diuretics, treatment with loop diuretics was independently associated with higher adjusted urinary calcium (55.0 versus 39.6 mg/day; P < 0.001), higher adjusted PTH [67.9, 95% confidence interval (CI) 65.2–70.7 pg/mL, versus 52.8, 95% CI 51.1–54.6 pg/mL, P < 0.001] and greater odds of secondary hyperparathyroidism (odds ratio 2.1; 95% CI 1.7–2.6). Thiazide monotherapy was associated with lower calciuria (25.5 versus 39.6 mg/day; P < 0.001) but only modestly lower PTH levels (50.0, 95% CI 47.8–52.3, versus 520.8, 95% CI 51.1–54.6 pg/mL, P = 0.04) compared with no diuretics. However, coadministration of thiazide and loop diuretics was associated with blunted urinary calcium (30.3 versus 55.0 mg/day; P <0.001) and odds of hyperparathyroidism (odds ratio 1.3 versus 2.1; P for interaction = 0.05) compared with loop diuretics alone. Conclusions. Loop diuretic use was associated with greater calciuria, PTH levels and odds of secondary hyperparathyroidism compared to no treatment. These associations were attenuated in patients who were coadministered thiazides. Diuretic choice is a potentially modifiable determinant of secondary hyperparathyroidism in CKD. PMID:21382989

Renoprotective effects of thiazides combined with loop diuretics in patients with type 2 diabetic kidney disease.

PubMed

Hoshino, Taro; Ookawara, Susumu; Miyazawa, Haruhisa; Ito, Kiyonori; Ueda, Yuichiro; Kaku, Yoshio; Hirai, Keiji; Mori, Honami; Yoshida, Izumi; Tabei, Kaoru

2015-04-01

Type 2 diabetic kidney disease (DKD) is frequently accompanied by uncontrollable hypertension due to the sodium sensitivity inherent in DKD and to diuretic-resistant edema. In general, diuretics are effective in treating this condition, but thiazide diuretics are thought to be innocuous in advanced chronic kidney disease (CKD). We examined the renoprotective effects of combination therapy with thiazides and loop diuretics in type 2 DKD patients with CKD stage G4 or G5. This study included 11 patients with type 2 DKD and an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m(2) who were suffering from severe edema even with loop diuretics. Each patient received additional hydrochlorothiazide (HCTZ) therapy, which was continued for more than 12 months. We examined clinical parameters including blood pressure (BP), proteinuria, and eGFR before and after the addition of HCTZ. Patients received a 13.6 ± 3.8 mg/day dose of HCTZ in addition to loop diuretics (azosemide: 120 mg/day in 6 cases, 60 mg/day in 3 cases and furosemide: 80 mg/day in 1 case, 120 mg/day in 1 case). Side effects of HCTZ were not observed in all patients. After the addition of HCTZ therapy, systolic and diastolic blood pressures (S-BP, D-BP) as well as proteinuria significantly decreased (S-BP: at 6 months, p < 0.05 and 12 months, p < 0.01 vs. 0 month, D-BP: at 12 months, p < 0.05 vs. 0 month, proteinuria: at 6 months, p < 0.05 and 12 months, p < 0.01 vs. 0 month). The annual decline in eGFR was not significantly different before and after HCTZ therapy (-7.7 ± 8.5 and -8.4 ± 4.8 mL/min/1.73 m(2)/year, respectively). Our findings suggest that the combination of HCTZ and loop diuretics improves BP levels, and decreases proteinuria even in advanced stage type 2 DKD patients with severe edema. The addition of HCTZ therapy was not found to negatively affect the change in eGFR in the present study.

Comparison of single and combination diuretics on glucose tolerance (PATHWAY-3): protocol for a randomised double-blind trial in patients with essential hypertension.

PubMed

Brown, Morris J; Williams, Bryan; MacDonald, Thomas M; Caulfield, Mark; Cruickshank, J Kennedy; McInnes, Gordon; Sever, Peter; Webb, David J; Salsbury, Jackie; Morant, Steve; Ford, Ian

2015-08-07

Thiazide diuretics are associated with increased risk of diabetes mellitus. This risk may arise from K(+)-depletion. We hypothesised that a K(+)-sparing diuretic will improve glucose tolerance, and that combination of low-dose thiazide with K(+)-sparing diuretic will improve both blood pressure reduction and glucose tolerance, compared to a high-dose thiazide. This is a parallel-group, randomised, double-blind, multicentre trial, comparing hydrochlorothiazide 25-50 mg, amiloride 10-20 mg and combination of both diuretics at half these doses. A single-blind placebo run-in of 1 month is followed by 24 weeks of blinded active treatment. There is forced dose-doubling after 3 months. The Primary end point is the blood glucose 2 h after oral ingestion of a 75 g glucose drink (OGTT), following overnight fasting. The primary outcome is the difference between 2 h glucose at weeks 0, 12 and 24. Secondary outcomes include the changes in home systolic blood pressure (BP) and glycated haemoglobin and prediction of response by baseline plasma renin. Eligibility criteria are: age 18-79, systolic BP on permitted background treatment ≥ 140 mm Hg and home BP ≥ 130 mm Hg and one component of the metabolic syndrome additional to hypertension. Principal exclusions are diabetes, estimated-glomerular filtration rate <45 mL/min, abnormal plasma K(+), clinic SBP >200 mm Hg or DBP >120 mm Hg (box 2). The sample size calculation indicates that 486 patients will give 80% power at α=0.01 to detect a difference in means of 1 mmol/L (SD=2.2) between 2 h glucose on hydrochlorothiazide and comparators. PATHWAY-3 was approved by Cambridge South Ethics Committee, number 09/H035/19. The trial results will be published in a peer-reviewed scientific journal. Eudract number 2009-010068-41 and clinical trials registration number: NCT02351973. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

First-line drugs for hypertension.

PubMed

Wright, James M; Musini, Vijaya M; Gill, Rupam

2018-04-18

This is the first update of a review published in 2009. Sustained moderate to severe elevations in resting blood pressure leads to a critically important clinical question: What class of drug to use first-line? This review attempted to answer that question. To quantify the mortality and morbidity effects from different first-line antihypertensive drug classes: thiazides (low-dose and high-dose), beta-blockers, calcium channel blockers, ACE inhibitors, angiotensin II receptor blockers (ARB), and alpha-blockers, compared to placebo or no treatment.Secondary objectives: when different antihypertensive drug classes are used as the first-line drug, to quantify the blood pressure lowering effect and the rate of withdrawal due to adverse drug effects, compared to placebo or no treatment. The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials up to November 2017: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 1946), Embase (from 1974), the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We contacted authors of relevant papers regarding further published and unpublished work. Randomized trials (RCT) of at least one year duration, comparing one of six major drug classes with a placebo or no treatment, in adult patients with blood pressure over 140/90 mmHg at baseline. The majority (over 70%) of the patients in the treatment group were taking the drug class of interest after one year. We included trials with both hypertensive and normotensive patients in this review if the majority (over 70%) of patients had elevated blood pressure, or the trial separately reported outcome data on patients with elevated blood pressure. The outcomes assessed were mortality, stroke, coronary heart disease (CHD), total cardiovascular events (CVS), decrease in systolic and diastolic blood pressure, and withdrawals due to adverse drug effects. We used a fixed-effect model to to combine dichotomous outcomes across trials and calculate risk ratio (RR) with 95% confidence interval (CI). We presented blood pressure data as mean difference (MD) with 99% CI. The 2017 updated search failed to identify any new trials. The original review identified 24 trials with 28 active treatment arms, including 58,040 patients. We found no RCTs for ARBs or alpha-blockers. These results are mostly applicable to adult patients with moderate to severe primary hypertension. The mean age of participants was 56 years, and mean duration of follow-up was three to five years.High-quality evidence showed that first-line low-dose thiazides reduced mortality (11.0% with control versus 9.8% with treatment; RR 0.89, 95% CI 0.82 to 0.97); total CVS (12.9% with control versus 9.0% with treatment; RR 0.70, 95% CI 0.64 to 0.76), stroke (6.2% with control versus 4.2% with treatment; RR 0.68, 95% CI 0.60 to 0.77), and coronary heart disease (3.9% with control versus 2.8% with treatment; RR 0.72, 95% CI 0.61 to 0.84).Low- to moderate-quality evidence showed that first-line high-dose thiazides reduced stroke (1.9% with control versus 0.9% with treatment; RR 0.47, 95% CI 0.37 to 0.61) and total CVS (5.1% with control versus 3.7% with treatment; RR 0.72, 95% CI 0.63 to 0.82), but did not reduce mortality (3.1% with control versus 2.8% with treatment; RR 0.90, 95% CI 0.76 to 1.05), or coronary heart disease (2.7% with control versus 2.7% with treatment; RR 1.01, 95% CI 0.85 to 1.20).Low- to moderate-quality evidence showed that first-line beta-blockers did not reduce mortality (6.2% with control versus 6.0% with treatment; RR 0.96, 95% CI 0.86 to 1.07) or coronary heart disease (4.4% with control versus 3.9% with treatment; RR 0.90, 95% CI 0.78 to 1.03), but reduced stroke (3.4% with control versus 2.8% with treatment; RR 0.83, 95% CI 0.72 to 0.97) and total CVS (7.6% with control versus 6.8% with treatment; RR 0.89, 95% CI 0.81 to 0.98).Low- to moderate-quality evidence showed that first-line ACE inhibitors reduced mortality (13.6% with control versus 11.3% with treatment; RR 0.83, 95% CI 0.72 to 0.95), stroke (6.0% with control versus 3.9% with treatment; RR 0.65, 95% CI 0.52 to 0.82), coronary heart disease (13.5% with control versus 11.0% with treatment; RR 0.81, 95% CI 0.70 to 0.94), and total CVS (20.1% with control versus 15.3% with treatment; RR 0.76, 95% CI 0.67 to 0.85).Low-quality evidence showed that first-line calcium channel blockers reduced stroke (3.4% with control versus 1.9% with treatment; RR 0.58, 95% CI 0.41 to 0.84) and total CVS (8.0% with control versus 5.7% with treatment; RR 0.71, 95% CI 0.57 to 0.87), but not coronary heart disease (3.1% with control versus 2.4% with treatment; RR 0.77, 95% CI 0.55 to 1.09), or mortality (6.0% with control versus 5.1% with treatment; RR 0.86, 95% CI 0.68 to 1.09).There was low-quality evidence that withdrawals due to adverse effects were increased with first-line low-dose thiazides (5.0% with control versus 11.3% with treatment; RR 2.38, 95% CI 2.06 to 2.75), high-dose thiazides (2.2% with control versus 9.8% with treatment; RR 4.48, 95% CI 3.83 to 5.24), and beta-blockers (3.1% with control versus 14.4% with treatment; RR 4.59, 95% CI 4.11 to 5.13). No data for these outcomes were available for first-line ACE inhibitors or calcium channel blockers. The blood pressure data were not used to assess the effect of the different classes of drugs as the data were heterogeneous, and the number of drugs used in the trials differed. First-line low-dose thiazides reduced all morbidity and mortality outcomes in adult patients with moderate to severe primary hypertension. First-line ACE inhibitors and calcium channel blockers may be similarly effective, but the evidence was of lower quality. First-line high-dose thiazides and first-line beta-blockers were inferior to first-line low-dose thiazides.

[Pharmacogenic osteoporosis beyond cortisone. Proton pump inhibitors, glitazones and diuretics].

PubMed

Kann, P H; Hadji, P; Bergmann, R S

2014-05-01

[corrected] There are many drugs which can cause osteoporosis or at least favor its initiation. The effect of hormones and drugs with antihormonal activity, such as glucocorticoids and aromatase inhibitors, on initiation of osteoporosis is well known. In addition, proton pump inhibitors, glitazones and diuretics also influence the formation of osteoporosis. The results of currently available studies on the correlation between proton pump inhibitors, glitazones and diuretics on formation of osteoporosis were evaluated and summarized. Proton pump inhibitors and glitazones increase the risk for osteoporotic fractures. Loop diuretics may slightly increase fracture risk, whereas thiazides were shown to be osteoprotective by reducing fracture probability on a relevant scale. Proton pump inhibitors should not be prescribed without serious consideration and then only as long as necessary. Alternatively, the administration of the less effective H2 antagonists should be considered when possible due to the reduction of acid secretion. Because the long-term intake of thiazides is associated with a clinically relevant reduction in the risk of fractures and they are economic and well-tolerated, prescription can be thoroughly recommended within the framework of differential diagnostic considerations in an appropriate clinical context. The briefly increased risk of falling immediately after starting diuretic therapy is the only point which needs to be considered.

γ-Adducin Stimulates the Thiazide-sensitive NaCl Cotransporter

PubMed Central

Dimke, Henrik; San-Cristobal, Pedro; de Graaf, Mark; Lenders, Jacques W.; Deinum, Jaap; Hoenderop, Joost G.J.

2011-01-01

The thiazide-sensitive NaCl cotransporter (NCC) plays a key role in renal salt reabsorption and the determination of systemic BP, but the molecular mechanisms governing the regulation of NCC are not completely understood. Here, through pull-down experiments coupled to mass spectrometry, we found that γ-adducin interacts with the NCC transporter. γ-Adducin colocalized with NCC to the distal convoluted tubule. 22Na+ uptake experiments in the Xenopus laevis oocyte showed that γ-adducin stimulated NCC activity in a dose-dependent manner, an effect that occurred upstream from With No Lysine (WNK) 4 kinase. The binding site of γ-adducin mapped to the N terminus of NCC and encompassed three previously reported phosphorylation sites. Supporting this site of interaction, competition with the N-terminal domain of NCC abolished the stimulatory effect of γ-adducin on the transporter. γ-Adducin failed to increase NCC activity when these phosphorylation sites were constitutively inactive or active. In addition, γ-adducin bound only to the dephosphorylated N terminus of NCC. Taken together, our observations suggest that γ-adducin dynamically regulates NCC, likely by amending the phosphorylation state, and consequently the activity, of the transporter. These data suggest that γ-adducin may influence BP homeostasis by modulating renal NaCl transport. PMID:21164023

Renal Calculi

PubMed Central

Yendt, E. R.

1970-01-01

The pathogenesis of renal calculi is reviewed in general terms followed by the results of investigation of 439 patients with renal calculi studied by the author at Toronto General Hospital over a 13-year period. Abnormalities of probable pathogenetic significance were encountered in 76% of patients. Idiopathic hypercalciuria was encountered in 42% of patients, primary hyperparathyroidism in 11%, urinary infection in 8% and miscellaneous disorders in 8%. The incidence of uric acid stones and cystinuria was 5% and 2% respectively. In the remaining 24% of patients in whom no definite abnormalities were encountered the mean urinary magnesium excretion was less than normal. Of 180 patients with idiopathic hypercalciuria, only 24 were females. In the diagnosis of hyperparathyroidism, the importance of detecting minimal degrees of hypercalcemia is stressed; attention is also drawn to the new observation that the upper limit of normal for serum calcium is slightly lower in females than in males. The efficacy of various measures advocated for the prevention of renal calculi is also reviewed. In the author's experience the administration of thiazides has been particularly effective in the prevention of calcium stones. Thiazides cause a sustained reduction in urinary calcium excretion and increase in urinary magnesium excretion. These agents also appear to affect the skeleton by diminishing bone resorption and slowing down bone turnover. PMID:5438766

Testing a TheoRY-inspired MEssage ('TRY-ME'): a sub-trial within the Ontario Printed Educational Message (OPEM) trial

PubMed Central

Francis, Jillian J; Grimshaw, Jeremy M; Zwarenstein, Merrick; Eccles, Martin P; Shiller, Susan; Godin, Gaston; Johnston, Marie; O'Rourke, Keith; Presseau, Justin; Tetroe, Jacqueline

2007-01-01

Background A challenge for implementation researchers is to develop principles that could generate testable hypotheses that apply across a range of clinical contexts, thus leading to generalisability of findings. Such principles may be provided by systematically developed theories. The opportunity has arisen to test some of these theoretical principles in the Ontario Printed Educational Materials (OPEM) trial by conducting a sub-trial within the existing trial structure. OPEM is a large factorial cluster-randomised trial evaluating the effects of short directive and long discursive educational messages embedded into informed, an evidence-based newsletter produced in Canada by the Institute for Clinical Evaluative Sciences (ICES) and mailed to all primary care physicians in Ontario. The content of educational messages in the sub-trial will be constructed using both standard methods and methods inspired by psychological theory. The aim of this study is to test the effectiveness of the TheoRY-inspired MEssage ('TRY-ME') compared with the 'standard' message in changing prescribing behaviour. Methods The OPEM trial participants randomised to receive the short directive message attached to the outside of informed (an 'outsert') will be sub-randomised to receive either a standard message or a message informed by the theory of planned behaviour (TPB) using a two (long insert or no insert) by three (theory-based outsert or standard outsert or no outsert) design. The messages will relate to prescription of thiazide diuretics as first line drug treatment for hypertension (described in the accompanying protocol, "The Ontario Printed Educational Materials trial"). The short messages will be developed independently by two research teams. The primary outcome is prescription of thiazide diuretics, measured by routinely collected data available within ICES. The study is designed to answer the question, is there any difference in guideline adherence (i.e., thiazide prescription rates) between physicians in the six groups? A process evaluation survey instrument based on the TPB will be administered pre- and post-intervention (described in the accompanying protocol, "Looking inside the black box"). The second research question concerns processes that may underlie observed differences in prescribing behaviour. We expect that effects of the messages on prescribing behaviour will be mediated through changes in physicians' cognitions. Trial registration number Current controlled trial ISRCTN72772651 PMID:18039363

The thiazide sensitive sodium chloride co-transporter NCC is modulated by site-specific ubiquitylation.

PubMed

Rosenbaek, Lena L; Rizzo, Federica; Wu, Qi; Rojas-Vega, Lorena; Gamba, Gerardo; MacAulay, Nanna; Staub, Olivier; Fenton, Robert A

2017-10-11

The renal sodium chloride cotransporter, NCC, in the distal convoluted tubule is important for maintaining body Na + and K + homeostasis. Endogenous NCC is highly ubiquitylated, but the role of individual ubiquitylation sites is not established. Here, we assessed the role of 10 ubiquitylation sites for NCC function. Transient transfections of HEK293 cells with human wildtype (WT) NCC or various K to R mutants identified greater membrane abundance for K706R, K828R and K909R mutants. Relative to WT-NCC, stable tetracycline inducible MDCKI cell lines expressing K706R, K828R and K909R mutants had significantly higher total and phosphorylated NCC levels at the apical plasma membrane under basal conditions. Low chloride stimulation increased membrane abundance of all mutants to similar or greater levels than WT-NCC. Under basal conditions K828R and K909R mutants had less ubiquitylated NCC in the plasma membrane, and all mutants displayed reduced NCC ubiquitylation following low chloride stimulation. Thiazide-sensitive sodium-22 uptakes were elevated in the mutants and internalization from the plasma membrane was significantly less than WT-NCC. K909R had increased half-life, whereas chloroquine or MG132 treatment indicated that K706 and K909 play roles in lysosomal and proteasomal NCC degradation, respectively. In conclusion, site-specific ubiquitylation of NCC plays alternative roles for NCC function.

Elevated FGF23 Levels in Mice Lacking the Thiazide-Sensitive NaCl cotransporter (NCC).

PubMed

Pathare, Ganesh; Anderegg, Manuel; Albano, Giuseppe; Lang, Florian; Fuster, Daniel G

2018-02-26

Fibroblast growth factor 23 (FGF23) participates in the orchestration of mineral metabolism by inducing phosphaturia and decreasing the production of 1,25(OH) 2 D 3 . It is known that FGF23 release is stimulated by aldosterone and extracellular volume depletion. To characterize this effect further in a model of mild hypovolemia, we studied mice lacking the thiazide sensitive NaCl cotransporter (NCC). Our data indicate that NCC knockout mice (KO) have significantly higher FGF23, PTH and aldosterone concentrations than corresponding wild type (WT) mice. However, 1,25(OH) 2 D 3 , fractional phosphate excretion and renal brush border expression of the sodium/phosphate co-transporter 2a were not different between the two genotypes. In addition, renal expression of FGF23 receptor FGFR1 and the co-receptor Klotho were unaltered in NCC KO mice. FGF23 transcript was increased in the bone of NCC KO mice compared to WT mice, but treatment of primary murine osteoblasts with the NCC inhibitor hydrochlorothiazide did not elicit an increase of FGF23 transcription. In contrast, the mineralocorticoid receptor blocker eplerenone reversed excess FGF23 levels in KO mice but not in WT mice, indicating that FGF23 upregulation in NCC KO mice is primarily aldosterone-mediated. Together, our data reveal that lack of renal NCC causes an aldosterone-mediated upregulation of circulating FGF23.

[Diuretic therapy in acute heart failure].

PubMed

Trullàs, Joan Carles; Morales-Rull, José Luis; Formiga, Francesc

2014-03-01

Diuretics are widely recommended in patients with acute heart failure (AHF). Unfortunately, despite their widespread use, limited data are available from randomized clinical trials to guide clinicians on the appropriate management of diuretic therapy. Loop diuretics are considered the first-line diuretic therapy, especially intravenous furosemide, but the best mode of administration (high-dose versus low-dose and continuous infusion versus bolus) is unclear. When diuretic resistance develops, different therapeutic strategies can be adopted, including combined diuretic therapy with thiazide diuretics and/or aldosterone antagonists. Low or "non-diuretic" doses (25-50mg QD) of aldosterone antagonists have been demonstrated to confer a survival benefit in patients with heart failure and reduced ejection fraction and consequently should be prescribed in all such patients, unless contraindicated by potassium and/or renal function values. There is less evidence on the use of aldosterone antagonists at higher or "diuretic" doses (≥ 100mg QD) but these drugs could be useful in relieving congestive symptoms in combination with furosemide. Thiazide diuretics can also be helpful as they have synergic effects with loop diuretics by inhibiting sodium reabsorption in distal parts of the nephron. The effect of diuretic therapy in AHF should be monitored with careful observation of clinical signs and symptoms of congestion. Serum electrolytes and kidney function should also be monitored during the use of intravenous diuretics. Copyright © 2014 Elsevier España, S.L. All rights reserved.

Risk of endometrial cancer in relation to medical conditions and medication use.

PubMed

Fortuny, Joan; Sima, Camelia; Bayuga, Sharon; Wilcox, Homer; Pulick, Katherine; Faulkner, Shameka; Zauber, Ann G; Olson, Sara H

2009-05-01

We studied the relation of medical conditions related to obesity and medications used for these conditions with endometrial cancer. We also investigated the association of other medical conditions and medications with risk. This U.S. population-based case-control study included 469 endometrial cancer cases and 467 controls. Information on putative risk factors for endometrial cancer was collected through personal interviews. We asked women about their medical history and medications used for six months or longer and the number of years each medication was taken. Risk was strongly associated with increasing obesity (P for trend < 0.001). Among the conditions related to obesity, and after adjustment for age, body mass index, and other risk factors and conditions, uterine fibroids were independently related to an increased cancer risk [adjusted odds ratio (OR), 1.8; 95% confidence interval (95% CI), 1.2-2.5]. Although hypertension was not significantly related to endometrial cancer after adjustment for age and body mass index, the use of thiazide diuretics was independently associated with increased risk (OR, 1.8; 95% CI, 1.1-3.0). Anemia was associated with decreased risk (OR, 0.6; 95% CI, 0.5-0.9). Use of nonsteroidal anti-inflammatory drugs was related to a decreased risk (OR, 0.7; 95% CI, 0.5-0.97). To our knowledge, the observation about thiazide diuretics is novel and requires confirmation in other studies and populations.

Diuretics: a review and update.

PubMed

Roush, George C; Kaur, Ramdeep; Ernst, Michael E

2014-01-01

Diuretics have been recommended as first-line treatment of hypertension and are also valuable in the management of hypervolemia and electrolyte disorders. This review summarizes the key features of the most commonly used diuretics. We then provide an update of clinical trials for diuretics during the past 5 years. Compared to other classes of medications, thiazide diuretics are at least as effective in reducing cardiovascular events (CVEs) in patients with hypertension and are more effective than β-blockers and angiotensin-converting enzyme inhibitors in reducing stroke. Observational cohort data and a network analysis have shown that CVEs are lowered by one-fifth from chlorthalidone when compared to the commonly used thiazide, hydrochlorothiazide. Relative to placebo, chlorthalidone increases life expectancy. In those aged 80 years and older, the diuretic, indapamide, lowers CVEs relative to placebo. The aldosterone antagonist, eplerenone, lowers total mortality in early congestive heart failure. The benefit of eplerenone following acute myocardial infarction (MI) is limited to administration within 3 to 6 days post-MI. Aldosterone antagonists have been shown to lower the incidence of sudden cardiac death and to reduce proteinuria. In the setting of heart failure, long acting loop diuretics azosemide and torasemide are more effective in improving heart failure outcomes than the far more commonly used short acting furosemide. Evening dosing of diuretics appears to lower CVEs relative to morning dosing. In conclusion, diuretics are a diverse class of drugs that remain extremely important in the management of hypertension and hypervolemic states.

Treatment regimens by pediatric nephrologists in children with congenital nephrogenic diabetes insipidus: A MWPNC study
.

PubMed

D'Alessandri-Silva, Cynthia; Carpenter, Melinda; Mahan, John D

2018-05-01

Congenital nephrogenic diabetes insipidus (NDI) is a rare genetic disorder affecting urinary concentration. Clinicians have varied medication regimens as well as nutritional plan approaches for these children. An electronic survey was distributed to member pediatric nephrologists of the Midwest Pediatric Nephrology Consortium via email (n = 179). Questions included types of drugs prescribed, factors contributing to drug choice, common drug combinations given, and dietary/failure to thrive interventions used. We analyzed results from 72 respondents (42% overall response rate). 72% treated only 1 - 3 patients with NDI per year, 12% treated 4 or more, and 17% had no NDI patients. Of providers treating NDI patients, almost all prescribed thiazides (93%), 62% prescribed amiloride, and 55% reported prescribing nonsteroidal anti-inflammatory drugs (NSAIDs) as part of their drug regimen. gastrointestinal (GI) and renal side effects (43%) were given as reasons for not prescribing indomethacin. For 70%, drug choice was determined by severity of failure to thrive (FTT). Physicians were asked to define the most common drug combinations they prescribed. 48% reported prescribing indomethacin with hydrochlorothiazide. 84% of respondents have a renal dietitian on staff, and half included appointments with a dietitian as part of FTT therapy. The most common intervention for FFT was gastrostomy tube placement (78%). Our results suggest consensus on the use of thiazides, while the use of indomethacin is limited by GI and renal side effect profile. Our results revealed that multiple drug combinations are frequently used without one specific preferred regimen.
.

Generation and analysis of the thiazide-sensitive Na+ -Cl- cotransporter (Ncc/Slc12a3) Ser707X knockin mouse as a model of Gitelman syndrome.

PubMed

Yang, Sung-Sen; Lo, Yi-Fen; Yu, I-Shing; Lin, Shu-Wha; Chang, Tai-Hsiang; Hsu, Yu-Juei; Chao, Tai-Kuang; Sytwu, Huey-Kang; Uchida, Shinichi; Sasaki, Sei; Lin, Shih-Hua

2010-12-01

Gitelman syndrome (GS) is characterized by salt-losing hypotension, hypomagnesemia, hypokalemic metabolic alkalosis, and hypocalciuria. To better model human GS caused by a specific mutation in the thiazide-sensitive Na(+) -Cl(-) cotransporter (NCC) gene SLC12A3, we generated a nonsense Ncc Ser707X knockin mouse corresponding to human p.Ser710X (c.2135C>A), a recurrent mutation with severe phenotypes in Chinese GS patients. Compared with wild-type or heterozygous littermates, homozygous (Hom) knockin mice fully recapitulated the phenotype of human GS. The markedly reduced Ncc mRNA and virtually absent Ncc protein expression in kidneys of Hom mice was primarily due to nonsense-mediated mRNA decay (NMD) surveillance mechanisms. Expression of epithelial Na(+) channel (Enac), Ca(2+) channels (Trpv5 and Trpv6), and K(+) channels (Romk1 and maxi-K) were significantly increased. Late distal convoluted tubules (DCT) volume was increased and DCT cell ultrastructure appeared intact. High K(+) intake could not correct hypokalemia but caused a further increase in maxi-K but not Romk1 expression. Renal tissue from a patient with GS also showed the enhanced TRPV5 and ROMK1 expression in distal tubules. We suggest that the upregulation of TRPV5/6 and of ROMK1 and Maxi-K may contribute to hypocalciuria and hypokalemia in Ncc Ser707X knockin mice and human GS, respectively. © 2010 Wiley-Liss, Inc.

Renal tubular NEDD4-2 deficiency causes NCC-mediated salt-dependent hypertension.

PubMed

Ronzaud, Caroline; Loffing-Cueni, Dominique; Hausel, Pierrette; Debonneville, Anne; Malsure, Sumedha Ram; Fowler-Jaeger, Nicole; Boase, Natasha A; Perrier, Romain; Maillard, Marc; Yang, Baoli; Stokes, John B; Koesters, Robert; Kumar, Sharad; Hummler, Edith; Loffing, Johannes; Staub, Olivier

2013-02-01

The E3 ubiquitin ligase NEDD4-2 (encoded by the Nedd4L gene) regulates the amiloride-sensitive epithelial Na+ channel (ENaC/SCNN1) to mediate Na+ homeostasis. Mutations in the human β/γENaC subunits that block NEDD4-2 binding or constitutive ablation of exons 6-8 of Nedd4L in mice both result in salt-sensitive hypertension and elevated ENaC activity (Liddle syndrome). To determine the role of renal tubular NEDD4-2 in adult mice, we generated tetracycline-inducible, nephron-specific Nedd4L KO mice. Under standard and high-Na+ diets, conditional KO mice displayed decreased plasma aldosterone but normal Na+/K+ balance. Under a high-Na+ diet, KO mice exhibited hypercalciuria and increased blood pressure, which were reversed by thiazide treatment. Protein expression of βENaC, γENaC, the renal outer medullary K+ channel (ROMK), and total and phosphorylated thiazide-sensitive Na+Cl- cotransporter (NCC) levels were increased in KO kidneys. Unexpectedly, Scnn1a mRNA, which encodes the αENaC subunit, was reduced and proteolytic cleavage of αENaC decreased. Taken together, these results demonstrate that loss of NEDD4-2 in adult renal tubules causes a new form of mild, salt-sensitive hypertension without hyperkalemia that is characterized by upregulation of NCC, elevation of β/γENaC, but not αENaC, and a normal Na+/K+ balance maintained by downregulation of ENaC activity and upregulation of ROMK.

Use of diuretics is associated with reduced risk of Alzheimer's disease: the Cache County Study.

PubMed

Chuang, Yi-Fang; Breitner, John C S; Chiu, Yen-Ling; Khachaturian, Ara; Hayden, Kathleen; Corcoran, Chris; Tschanz, JoAnn; Norton, Maria; Munger, Ron; Welsh-Bohmer, Kathleen; Zandi, Peter P

2014-11-01

Although the use of antihypertensive medications has been associated with reduced risk of Alzheimer's disease (AD), it remains unclear which class provides the most benefit. The Cache County Study of Memory Health and Aging is a prospective longitudinal cohort study of dementing illnesses among the elderly population of Cache County, Utah. Using waves I to IV data of the Cache County Study, 3417 participants had a mean of 7.1 years of follow-up. Time-varying use of antihypertensive medications including different class of diuretics, angiotensin converting enzyme inhibitors, β-blockers, and calcium channel blockers was used to predict the incidence of AD using Cox proportional hazards analyses. During follow-up, 325 AD cases were ascertained with a total of 23,590 person-years. Use of any antihypertensive medication was associated with lower incidence of AD (adjusted hazard ratio [aHR], 0.77; 95% confidence interval [CI], 0.61-0.97). Among different classes of antihypertensive medications, thiazide (aHR, 0.7; 95% CI, 0.53-0.93), and potassium-sparing diuretics (aHR, 0.69; 95% CI, 0.48-0.99) were associated with the greatest reduction of AD risk. Thiazide and potassium-sparing diuretics were associated with decreased risk of AD. The inverse association of potassium-sparing diuretics confirms an earlier finding in this cohort, now with longer follow-up, and merits further investigation. Copyright © 2014 Elsevier Inc. All rights reserved.

Use of diuretics is associated with reduced risk of Alzheimer’s disease: the Cache County Study

PubMed Central

Chuang, Yi-Fang; Breitner, John C.S.; Chiu, Yen-Ling; Khachaturian, Ara; Hayden, Kathleen; Corcoran, Chris; Tschanz, JoAnn; Norton, Maria; Munger, Ron; Welsh-Bohmer, Kathleen; Zandi, Peter P.

2015-01-01

Although the use of antihypertensive medications has been associated with reduced risk of Alzheimer’s disease (AD), it remains unclear which class provides the most benefit. The Cache County Study of Memory Health and Aging is a prospective longitudinal cohort study of dementing illnesses among the elderly population of Cache County, Utah. Using waves I to IV data of the Cache County Study, 3417 participants had a mean of 7.1 years of follow-up. Time-varying use of antihypertensive medications including different class of diuretics, angiotensin converting enzyme inhibitors, β-blockers, and calcium channel blockers was used to predict the incidence of AD using Cox proportional hazards analyses. During follow-up, 325 AD cases were ascertained with a total of 23,590 person-years. Use of any anti-hypertensive medication was associated with lower incidence of AD (adjusted hazard ratio [aHR], 0.77; 95% confidence interval [CI], 0.61–0.97). Among different classes of antihypertensive medications, thiazide (aHR, 0.7; 95% CI, 0.53–0.93), and potassium-sparing diuretics (aHR, 0.69; 95% CI, 0.48–0.99) were associated with the greatest reduction of AD risk. Thiazide and potassium-sparing diuretics were associated with decreased risk of AD. The inverse association of potassium-sparing diuretics confirms an earlier finding in this cohort, now with longer follow-up, and merits further investigation. PMID:24910391

Prostate cancer decision-making, health services, and the family physician workforce.

PubMed

Bowman, Marjorie A; Neale, Anne Victoria

2012-01-01

Does untreated cancer equal death? Does having a registered nurse versus a licensed practical nurse versus a medical assistant affect diabetes quality outcomes? Do physicians caring for stressed patients experience vicarious traumatic stress? Oregon presents an operationalized definition of a patient-centered medical home for their state. Lots of important clinical topics in family medicine--adult attention deficit disorder office questionnaire; Bell palsy; cancer screening and treatment decisions; lubrication during Papanicolaou testing; changes in maternity care training by residencies; changing prescribing patterns for thiazide diuretics; and night sweats remain a mystery.

Diuretics, first-line antihypertensive agents: are they always safe in the elderly?

PubMed

Diaconu, Camelia C; Balaceanu, Alice; Bartos, Daniela

2014-01-01

Diuretics are frequently recommended as antihypertensive agents. Some of the main side effects of diuretic therapy are hypokalaemia and hyponatremia. The objective of the study was to describe the frequency of hyponatremia in a group of elderly hypertensive patients treated with diuretics. The study included 202 elderly hypertensive patients (over 65 years old), treated with diuretics at least 4 weeks before hospitalization, consecutivly admitted in the Internal Medicine Clinic of the Clinical Emergency Hospital of Bucharest during a period of 4 months. The distribution by sex: 103 (52.28%) men and 94 (47.71%) women. The mean age of the patients was 72 ± 8 years. Incidence of hyponatremia was 24.87% (49 patients) in the whole group. From the 49 hyponatremic patients, 31 (63.26%) were women and 18 (36.73%) men. The distribution by age of hypertensive hyponatremic female patients was: between 65-70 years old--4 patients (12.90%), between 70-75 years old--7 patients (22.58%), over 75 years old--20 patients (64.51%). The distribution by age of hypertensive hyponatremic male patients was: between 65-70 years old--3 patients (16.66%), between 70-75 years old--2 patients(11.11%), over 75 years old--13 patients (72.22%). Most of the patients affected (73.46%) used a thiazide-type diuretic, the other 26.54% being on loop diuretics. Elderly hypertensive patients were more likely to develop hyponatremia after age 75. Female patients had a higher frequency of hyponatremia than male patients. The main cause of hyponatremia in patients treated with diuretics was thiazide.

Protein Phosphatase 1 Inhibitor-1 Deficiency Reduces Phosphorylation of Renal NaCl Cotransporter and Causes Arterial Hypotension

PubMed Central

Picard, Nicolas; Trompf, Katja; Yang, Chao-Ling; Miller, R. Lance; Carrel, Monique; Loffing-Cueni, Dominique; Fenton, Robert A.; Ellison, David H.

2014-01-01

The thiazide-sensitive NaCl cotransporter (NCC) of the renal distal convoluted tubule (DCT) controls ion homeostasis and arterial BP. Loss-of-function mutations of NCC cause renal salt wasting with arterial hypotension (Gitelman syndrome). Conversely, mutations in the NCC-regulating WNK kinases or kelch-like 3 protein cause familial hyperkalemic hypertension. Here, we performed automated sorting of mouse DCTs and microarray analysis for comprehensive identification of novel DCT-enriched gene products, which may potentially regulate DCT and NCC function. This approach identified protein phosphatase 1 inhibitor-1 (I-1) as a DCT-enriched transcript, and immunohistochemistry revealed I-1 expression in mouse and human DCTs and thick ascending limbs. In heterologous expression systems, coexpression of NCC with I-1 increased thiazide-dependent Na+ uptake, whereas RNAi-mediated knockdown of endogenous I-1 reduced NCC phosphorylation. Likewise, levels of phosphorylated NCC decreased by approximately 50% in I-1 (I-1−/−) knockout mice without changes in total NCC expression. The abundance and phosphorylation of other renal sodium-transporting proteins, including NaPi-IIa, NKCC2, and ENaC, did not change, although the abundance of pendrin increased in these mice. The abundance, phosphorylation, and subcellular localization of SPAK were similar in wild-type (WT) and I-1−/− mice. Compared with WT mice, I-1−/− mice exhibited significantly lower arterial BP but did not display other metabolic features of NCC dysregulation. Thus, I-1 is a DCT-enriched gene product that controls arterial BP, possibly through regulation of NCC activity. PMID:24231659

Functionomics of NCC mutations in Gitelman syndrome using a novel mammalian cell-based activity assay.

PubMed

Valdez-Flores, Marco A; Vargas-Poussou, Rosa; Verkaart, Sjoerd; Tutakhel, Omar A Z; Valdez-Ortiz, Angel; Blanchard, Anne; Treard, Cyrielle; Hoenderop, Joost G J; Bindels, René J M; Jeleń, Sabina

2016-12-01

Gitelman syndrome (GS) is an autosomal recessive salt-wasting tubular disorder resulting from loss-of-function mutations in the thiazide-sensitive NaCl cotransporter (NCC). Functional analysis of these mutations has been limited to the use of Xenopus laevis oocytes. The aim of the present study was, therefore, to analyze the functional consequences of NCC mutations in a mammalian cell-based assay, followed by analysis of mutated NCC protein expression as well as glycosylation and phosphorylation profiles using human embryonic kidney (HEK) 293 cells. NCC activity was assessed with a novel assay based on thiazide-sensitive iodide uptake in HEK293 cells expressing wild-type or mutant NCC (N59I, R83W, I360T, C421Y, G463R, G731R, L859P, or R861C). All mutations caused a significantly lower NCC activity. Immunoblot analysis of the HEK293 cells revealed that 1) all NCC mutants have decreased NCC protein expression; 2) mutant N59I, R83W, I360T, C421Y, G463R, and L859P have decreased NCC abundance at the plasma membrane; 3) mutants C421Y and L859P display impaired NCC glycosylation; and 4) mutants N59I, R83W, C421Y, C731R, and L859P show affected NCC phosphorylation. In conclusion, we developed a mammalian cell-based assay in which NCC activity assessment together with a profiling of mutated protein processing aid our understanding of the pathogenic mechanism of the NCC mutations. Copyright © 2016 the American Physiological Society.

Azilsartan/chlorthalidone combination therapy for blood pressure control.

PubMed

Cheng, Judy Wm

2013-01-01

Edarbyclor(®) is a combined angiotensin receptor blocker (ARB) and thiazide-like diuretic (azilsartan and chlorthalidone), and was approved on December 20, 2011 by the US Food and Drug Administration (FDA) for hypertension management. To review the pharmacology, pharmacokinetics, efficacy, safety, tolerability, and role of azilsartan plus chlorthalidone for hypertension management. Peer-reviewed clinical trials, review articles, and relevant treatment guidelines, were identified from the databases MEDLINE and Current Contents (both 1966 to February 15, 2013, inclusive) using search terms "azilsartan", "chlorthalidone", "pharmacology", "pharmacokinetics", "pharmacodynamics", "pharmacoeconomics", and "cost-effectiveness". The FDA website, as well as manufacturer prescribing information, was also reviewed to identify other relevant information. Azilsartan is a new ARB with high affinity for the angiotensin 1 receptor, approved by the FDA for hypertension management. Unlike other ARBs, azilsartan has no clinical data supporting improvement in cardiovascular outcomes, and is not approved for indications other than hypertension, which a select few other ARBs may be used for (eg, diabetic nephropathy and heart failure). Chlorthalidone is a longer acting thiazide-like diuretic that has been demonstrated to improve cardiovascular outcomes. Combination treatment with azilsartan/chlorthalidone is effective for reducing blood pressure. Compared to olmesartan/hydrochlorothiazide and azilsartan/hydrochlorothiazide combinations, azilsartan/chlorthalidone appears to be more efficacious for reducing blood pressure. Azilsartan/chlorthalidone can be considered an antihypertensive therapy option in patients for whom combination therapy is required (blood pressure >20 mmHg systolic or >10 mmHg diastolic above goal). Cost to patients and insurance coverage will probably determine whether azilsartan/chlorthalidone will be the most appropriate combination therapy for an individual patient.

Diuretics in primary hypertension - Reloaded.

PubMed

Mishra, Sundeep

Diuretics have long been cherished as drugs of choice for uncomplicated primary hypertension. Robust mortality and morbidity data is available for diuretics to back this strategy. Off-late the interest for diuretics has waned off perhaps due to availability of more effective drugs but more likely due to perceived lack of tolerance and side-effect profile of high-dose of diuretics required for mortality benefit. Low-dose diuretics particularly thiazide diuretics are safer but lack the mortality benefit shown by high-dose. However, indapamide and low dose chlorthalidone have fewer side-effects but continue to provide mortality benefit. Copyright © 2016. Published by Elsevier B.V.

Mini-review: regulation of the renal NaCl cotransporter by hormones.

PubMed

Rojas-Vega, Lorena; Gamba, Gerardo

2016-01-01

The renal thiazide-sensitive NaCl cotransporter, NCC, is the major pathway for salt reabsorption in the distal convoluted tubule. The activity of this cotransporter is critical for regulation of several physiological variables such as blood pressure, serum potassium, acid base metabolism, and urinary calcium excretion. Therefore, it is not surprising that numerous hormone-signaling pathways regulate NCC activity to maintain homeostasis. In this review, we will provide an overview of the most recent evidence on NCC modulation by aldosterone, angiotensin II, vasopressin, glucocorticoids, insulin, norepinephrine, estradiol, progesterone, prolactin, and parathyroid hormone. Copyright © 2016 the American Physiological Society.

Management of Essential Hypertension.

PubMed

Ferdinand, Keith C; Nasser, Samar A

2017-05-01

The treatment of essential hypertension is one of the most critical interventions to decrease cardiovascular morbidity and mortality. The prevalence of hypertension in the US varies across race/ethnicity with African Americans having the highest prevalence and overall less control among racial/ethnic minorities compared with non-Hispanic whites. Therapeutic lifestyle modifications are the bedrock of essential hypertension control, but most patients with hypertension will require pharmacotherapy, usually with multiple medications often in combination. Overall, the principal drug classes recommended as initial pharmacotherapy are thiazide-type diuretics, calcium channel blockers, and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Copyright © 2016 Elsevier Inc. All rights reserved.

Anti-hypertensive drugs and skin cancer risk: a review of the literature and meta-analysis.

PubMed

Gandini, Sara; Palli, Domenico; Spadola, Giuseppe; Bendinelli, Benedetta; Cocorocchio, Emilia; Stanganelli, Ignazio; Miligi, Lucia; Masala, Giovanna; Caini, Saverio

2018-02-01

Several anti-hypertensive drugs have photosensitizing properties, however it remains unclear whether long-term users of these drugs are also at increased risk of skin malignancies. We conducted a literature review and meta-analysis on the association between use of anti-hypertensive drugs and the risk of cutaneous melanoma and non-melanoma skin cancer (NMSC). We searched PubMed, EMBASE, Google Scholar and the Cochrane Library, and included observational and experimental epidemiological studies published until February 28th, 2017. We calculated summary relative risk (SRR) and 95% confidence intervals (95% CI) through random effect models to estimate the risk of skin malignancies among users of the following classes of anti-hypertensive drugs: thiazide diuretics, angiotensin converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARB), calcium channel blockers (CCB) and β-blockers. We conducted sub-group and sensitivity analysis to explore causes of between-studies heterogeneity, and assessed publication bias using a funnel-plot based approach. Nineteen independent studies were included in the meta-analysis. CCB users were at increased skin cancer risk (SRR 1.14, 95% CI 1.07-1.21), and β-blockers users were at increased risk of developing cutaneous melanoma (SRR 1.21, 95% CI 1.05-1.40), with acceptable between-studies heterogeneity (I 2  < 50%). There was no association between thiazide diuretics, ACEi or ARB use and skin cancer risk. We found no evidence of publication bias affecting the results. Family doctors and clinicians should inform their patients about the increased risk of skin cancer associated with the use of CCB and β-blockers and instruct them to perform periodic skin self-examination. Further studies are warranted to elucidate the observed associations. Copyright © 2017 Elsevier B.V. All rights reserved.

Aldosterone modulates thiazide-sensitive sodium chloride cotransporter abundance via DUSP6-mediated ERK1/2 signaling pathway.

PubMed

Feng, Xiuyan; Zhang, Yiqian; Shao, Ningjun; Wang, Yanhui; Zhuang, Zhizhi; Wu, Ping; Lee, Matthew J; Liu, Yingli; Wang, Xiaonan; Zhuang, Jieqiu; Delpire, Eric; Gu, Dingying; Cai, Hui

2015-05-15

Thiazide-sensitive sodium chloride cotransporter (NCC) plays an important role in maintaining blood pressure. Aldosterone is known to modulate NCC abundance. Previous studies reported that dietary salts modulated NCC abundance through either WNK4 [with no lysine (k) kinase 4]-SPAK (Ste20-related proline alanine-rich kinase) or WNK4-extracellular signal-regulated kinase-1 and -2 (ERK1/2) signaling pathways. To exclude the influence of SPAK signaling pathway on the role of the aldosterone-mediated ERK1/2 pathway in NCC regulation, we investigated the effects of dietary salt changes and aldosterone on NCC abundance in SPAK knockout (KO) mice. We found that in SPAK KO mice low-salt diet significantly increased total NCC abundance while reducing ERK1/2 phosphorylation, whereas high-salt diet decreased total NCC while increasing ERK1/2 phosphorylation. Importantly, exogenous aldosterone administration increased total NCC abundance in SPAK KO mice while increasing DUSP6 expression, an ERK1/2-specific phosphatase, and led to decreasing ERK1/2 phosphorylation without changing the ratio of phospho-T53-NCC/total NCC. In mouse distal convoluted tubule (mDCT) cells, aldosterone increased DUSP6 expression while reducing ERK1/2 phosphorylation. DUSP6 Knockdown increased ERK1/2 phosphorylation while reducing total NCC expression. Inhibition of DUSP6 by (E)-2-benzylidene-3-(cyclohexylamino)-2,3-dihydro-1H-inden-1-one increased ERK1/2 phosphorylation and reversed the aldosterone-mediated increments of NCC partly by increasing NCC ubiquitination. Therefore, these data suggest that aldosterone modulates NCC abundance via altering NCC ubiquitination through a DUSP6-dependent ERK1/2 signal pathway in SPAK KO mice and part of the effects of dietary salt changes may be mediated by aldosterone in the DCTs.

Arterial hypertension after age 65: from epidemiology and pathophysiology to therapy Do we know where we stand?

PubMed

Gąsowski, Jerzy; Piotrowicz, Karolina; Messerli, Franz H

2018-01-01

Arterial hypertension is a prevalent disease with great harming potential. After the age of 55 years the remaining lifetime risk of hypertension amounts to 90%. Despite the constant advances some important issues such as the cut-off blood pressure for the initiation of antihypertensive therapy or the therapeutic goal are debated. In this review, we present - based on the available literature - the current concepts concerning the pathophysiology, epi-demiology and antihypertensive therapy in patients aged 65 years or older. The pathophysiology of hypertension in older patients in principle rests on stiffening of large conduit arteries, which leads to greater systolic and lower diastolic blood pressure. This in most older patients results in isolated systolic hypertension. Additionally most of these patients have low-renin hypertension. Data from large-scale clinical trials indicate that therapy of such individuals with thiazide-like diuretics and long-acting dihydropiridine calcium channel blockers as first-line medications reduces risk of complications. Based on results of recently published trials, meta-analyses, and prospective observations, the optimal on-treatment blood pressure values for most older hypertensive patients should be set within the 130-139 mmHg range. At present, lower values of standard office blood pressure in this group of patients have not been shown to be associ-ated with additional benefits, and may be associated with a greater risk of adverse events. In conclusion, we recommend that for most patients aged 65 years or more, standard office systolic blood pressure should be cautiously reduced to within 140 and 130 mmHg, preferably with a thiazide-like diuretic, long acting dihydropiridine calcium channel blocker or their combination.

Mechanisms of renal control of potassium homeostasis in complete aldosterone deficiency.

PubMed

Todkar, Abhijeet; Picard, Nicolas; Loffing-Cueni, Dominique; Sorensen, Mads V; Mihailova, Marija; Nesterov, Viatcheslav; Makhanova, Natalia; Korbmacher, Christoph; Wagner, Carsten A; Loffing, Johannes

2015-02-01

Aldosterone-independent mechanisms may contribute to K(+) homeostasis. We studied aldosterone synthase knockout (AS(-/-)) mice to define renal control mechanisms of K(+) homeostasis in complete aldosterone deficiency. AS(-/-) mice were normokalemic and tolerated a physiologic dietary K(+) load (2% K(+), 2 days) without signs of illness, except some degree of polyuria. With supraphysiologic K(+) intake (5% K(+)), AS(-/-) mice decompensated and became hyperkalemic. High-K(+) diets induced upregulation of the renal outer medullary K(+) channel in AS(-/-) mice, whereas upregulation of the epithelial sodium channel (ENaC) sufficient to increase the electrochemical driving force for K(+) excretion was detected only with a 2% K(+) diet. Phosphorylation of the thiazide-sensitive NaCl cotransporter was consistently lower in AS(-/-) mice than in AS(+/+) mice and was downregulated in mice of both genotypes in response to increased K(+) intake. Inhibition of the angiotensin II type 1 receptor reduced renal creatinine clearance and apical ENaC localization, and caused severe hyperkalemia in AS(-/-) mice. In contrast with the kidney, the distal colon of AS(-/-) mice did not respond to dietary K(+) loading, as indicated by Ussing-type chamber experiments. Thus, renal adaptation to a physiologic, but not supraphysiologic, K(+) load can be achieved in aldosterone deficiency by aldosterone-independent activation of the renal outer medullary K(+) channel and ENaC, to which angiotensin II may contribute. Enhanced urinary flow and reduced activity of the thiazide-sensitive NaCl cotransporter may support renal adaptation by activation of flow-dependent K(+) secretion and increased intratubular availability of Na(+) that can be reabsorbed in exchange for K(+) secreted. Copyright © 2015 by the American Society of Nephrology.

Hsp70 and Hsp90 Multichaperone Complexes Sequentially Regulate Thiazide-sensitive Cotransporter Endoplasmic Reticulum-associated Degradation and Biogenesis*

PubMed Central

Donnelly, Bridget F.; Needham, Patrick G.; Snyder, Avin C.; Roy, Ankita; Khadem, Shaheen; Brodsky, Jeffrey L.; Subramanya, Arohan R.

2013-01-01

The thiazide-sensitive NaCl cotransporter (NCC) is the primary mediator of salt reabsorption in the distal convoluted tubule and is a key determinant of the blood pressure set point. Given its complex topology, NCC is inefficiently processed and prone to endoplasmic reticulum (ER)-associated degradation (ERAD), although the mechanisms governing this process remain obscure. Here, we identify factors that impact the ER quality control of NCC. Analyses of NCC immunoprecipitates revealed that the cotransporter formed complexes with the core chaperones Hsp90, Hsp70, and Hsp40. Disruption of Hsp90 function accelerated NCC degradation, suggesting that Hsp90 promotes NCC folding. In addition, two cochaperones, the C terminus of Hsp70-interacting protein (CHIP) and the Hsp70/Hsp90 organizer protein, were associated with NCC. Although CHIP, an E3 ubiquitin ligase, promoted NCC ubiquitination and ERAD, the Hsp70/Hsp90 organizer protein stabilized NCC turnover, indicating that these two proteins differentially remodel the core chaperone systems to favor cotransporter degradation and biogenesis, respectively. Adjusting the folding environment in mammalian cells via reduced temperature enhanced NCC biosynthetic trafficking, increased Hsp90-NCC interaction, and diminished binding to Hsp70. In contrast, cotransporters harboring disease-causing mutations that impair NCC biogenesis failed to escape ERAD as efficiently as the wild type protein when cells were incubated at a lower temperature. Instead, these mutants interacted more strongly with Hsp70, Hsp40, and CHIP, consistent with a role for the Hsp70/Hsp40 system in selecting misfolded NCC for ERAD. Collectively, these observations indicate that Hsp70 and Hsp90 comprise two functionally distinct ER quality control checkpoints that sequentially monitor NCC biogenesis. PMID:23482560

Phosphorylation Regulates NCC Stability and Transporter Activity In Vivo

PubMed Central

Yang, Sung-Sen; Fang, Yu-Wei; Tseng, Min-Hua; Chu, Pei-Yi; Yu, I-Shing; Wu, Han-Chung; Lin, Shu-Wha; Chau, Tom; Uchida, Shinichi; Sasaki, Sei; Lin, Yuh-Feng; Sytwu, Huey-Kang

2013-01-01

A T60M mutation in the thiazide-sensitive sodium chloride cotransporter (NCC) is common in patients with Gitelman’s syndrome (GS). This mutation prevents Ste20-related proline and alanine-rich kinase (SPAK)/oxidative stress responsive kinase-1 (OSR1)–mediated phosphorylation of NCC and alters NCC transporter activity in vitro. Here, we examined the physiologic effects of NCC phosphorylation in vivo using a novel Ncc T58M (human T60M) knock-in mouse model. NccT58M/T58M mice exhibited typical features of GS with a blunted response to thiazide diuretics. Despite expressing normal levels of Ncc mRNA, these mice had lower levels of total Ncc and p-Ncc protein that did not change with a low-salt diet that increased p-Spak. In contrast to wild-type Ncc, which localized to the apical membrane of distal convoluted tubule cells, T58M Ncc localized primarily to the cytosolic region and caused an increase in late distal convoluted tubule volume. In MDCK cells, exogenous expression of phosphorylation-defective NCC mutants reduced total protein expression levels and membrane stability. Furthermore, our analysis found diminished total urine NCC excretion in a cohort of GS patients with homozygous NCC T60M mutations. When Wnk4D561A/+ mice, a model of pseudohypoaldosteronism type II expressing an activated Spak/Osr1-Ncc, were crossed with NccT58M/T58M mice, total Ncc and p-Ncc protein levels decreased and the GS phenotype persisted over the hypertensive phenotype. Overall, these data suggest that SPAK-mediated phosphorylation of NCC at T60 regulates NCC stability and function, and defective phosphorylation at this residue corrects the phenotype of pseudohypoaldosteronism type II. PMID:23833262

A new model of the distal convoluted tubule

PubMed Central

Ko, Benjamin; Mistry, Abinash C.; Hanson, Lauren; Mallick, Rickta; Cooke, Leslie L.; Hack, Bradley K.; Cunningham, Patrick

2012-01-01

The Na+-Cl− cotransporter (NCC) in the distal convoluted tubule (DCT) of the kidney is a key determinant of Na+ balance. Disturbances in NCC function are characterized by disordered volume and blood pressure regulation. However, many details concerning the mechanisms of NCC regulation remain controversial or undefined. This is partially due to the lack of a mammalian cell model of the DCT that is amenable to functional assessment of NCC activity. Previously reported investigations of NCC regulation in mammalian cells have either not attempted measurements of NCC function or have required perturbation of the critical without a lysine kinase (WNK)/STE20/SPS-1-related proline/alanine-rich kinase regulatory pathway before functional assessment. Here, we present a new mammalian model of the DCT, the mouse DCT15 (mDCT15) cell line. These cells display native NCC function as measured by thiazide-sensitive, Cl−-dependent 22Na+ uptake and allow for the separate assessment of NCC surface expression and activity. Knockdown by short interfering RNA confirmed that this function was dependent on NCC protein. Similar to the mammalian DCT, these cells express many of the known regulators of NCC and display significant baseline activity and dimerization of NCC. As described in previous models, NCC activity is inhibited by appropriate concentrations of thiazides, and phorbol esters strongly suppress function. Importantly, they display release of WNK4 inhibition of NCC by small hairpin RNA knockdown. We feel that this new model represents a critical tool for the study of NCC physiology. The work that can be accomplished in such a system represents a significant step forward toward unraveling the complex regulation of NCC. PMID:22718890

Exploring the intricate regulatory network controlling the thiazide-sensitive NaCl cotransporter (NCC).

PubMed

Dimke, Henrik

2011-12-01

The thiazide-sensitive NaCl cotransporter (NCC) plays key roles in renal electrolyte transport and blood pressure maintenance. Regulation of this cotransporter has received increased attention recently, prompted by the discovery that mutations in the with-no-lysine (WNK) kinases are the molecular explanation for pseudohypoaldosteronism type II (PHAII). Studies suggest that WNK4 regulates NCC via two distinct pathways, depending on its state of activation. Furthermore, an intact STE20-related proline-alanine-rich kinase (SPAK)/oxidative stress response 1 kinase (OSR1) pathway was found to be necessary for a WNK4 PHAII mutation to increase NCC phosphorylation and blood pressure in mice. The mouse protein 25α is a novel regulator of the SPAK/OSR1 kinase family, which greatly increases their activity. The phosphorylation status of NCC and the WNK is regulated by the serum- and glucocorticoid-inducible kinase 1, suggesting novel mechanisms whereby aldosterone modulates NCC activity. Dephosphorylation of NCC by protein phosphatase 4 strongly influences the activity of the cotransporter, confirming an important role for NCC phosphorylation. Finally, γ-adducin increases NCC activity. This stimulatory effect is dependent on the phosphorylation status of the cotransporter. γ-Adducin only binds the dephosphorylated cotransporter, suggesting that phosphorylation of NCC causes the dissociation of γ-adducin. Since γ-adducin is not a kinase, it is tempting to speculate that the protein exerts its function by acting as a scaffold between the dephosphorylated cotransporter and the regulatory kinase. As more molecular regulators of NCC are identified, the system-controlling NCC activity is becoming increasingly complex. This intricacy confers an ability to integrate a variety of stimuli, thereby regulating NCC transport activity and ultimately blood pressure.

Phosphorylation decreases ubiquitylation of the thiazide-sensitive cotransporter NCC and subsequent clathrin-mediated endocytosis.

PubMed

Rosenbaek, Lena L; Kortenoeven, Marleen L A; Aroankins, Takwa S; Fenton, Robert A

2014-05-09

The thiazide-sensitive sodium chloride cotransporter, NCC, is the major NaCl transport protein in the distal convoluted tubule (DCT). The transport activity of NCC can be regulated by phosphorylation, but knowledge of modulation of NCC trafficking by phosphorylation is limited. In this study, we generated novel tetracycline-inducible Madin-Darby canine kidney type I (MDCKI) cell lines expressing NCC to examine the role of NCC phosphorylation and ubiquitylation on NCC endocytosis. In MDCKI-NCC cells, NCC was highly glycosylated at molecular weights consistent with NCC monomers and dimers. NCC constitutively cycles to the apical plasma membrane of MDCKI-NCC cells, with 20-30% of the membrane pool of NCC internalized within 30 min. The use of dynasore, PitStop2, methyl-β-cyclodextrin, nystatin, and filipin (specific inhibitors of either clathrin-dependent or -independent endocytosis) demonstrated that NCC is internalized via a clathrin-mediated pathway. Reduction of endocytosis resulted in greater levels of NCC in the plasma membrane. Immunogold electron microscopy confirmed the association of NCC with the clathrin-mediated internalization pathway in rat DCT cells. Compared with controls, inducing phosphorylation of NCC via low chloride treatment or mimicking phosphorylation by replacing Thr-53, Thr-58, and Ser-71 residues with Asp resulted in increased membrane abundance and reduced rates of NCC internalization. NCC ubiquitylation was lowest in the conditions with greatest NCC phosphorylation, thus providing a mechanism for the reduced endocytosis. In conclusion, our data support a model where NCC is constitutively cycled to the plasma membrane, and upon stimulation, it can be phosphorylated to both increase NCC activity and decrease NCC endocytosis, together increasing NaCl transport in the DCT.

Phosphorylation Decreases Ubiquitylation of the Thiazide-sensitive Cotransporter NCC and Subsequent Clathrin-mediated Endocytosis*

PubMed Central

Rosenbaek, Lena L.; Kortenoeven, Marleen L. A.; Aroankins, Takwa S.; Fenton, Robert A.

2014-01-01

The thiazide-sensitive sodium chloride cotransporter, NCC, is the major NaCl transport protein in the distal convoluted tubule (DCT). The transport activity of NCC can be regulated by phosphorylation, but knowledge of modulation of NCC trafficking by phosphorylation is limited. In this study, we generated novel tetracycline-inducible Madin-Darby canine kidney type I (MDCKI) cell lines expressing NCC to examine the role of NCC phosphorylation and ubiquitylation on NCC endocytosis. In MDCKI-NCC cells, NCC was highly glycosylated at molecular weights consistent with NCC monomers and dimers. NCC constitutively cycles to the apical plasma membrane of MDCKI-NCC cells, with 20–30% of the membrane pool of NCC internalized within 30 min. The use of dynasore, PitStop2, methyl-β-cyclodextrin, nystatin, and filipin (specific inhibitors of either clathrin-dependent or -independent endocytosis) demonstrated that NCC is internalized via a clathrin-mediated pathway. Reduction of endocytosis resulted in greater levels of NCC in the plasma membrane. Immunogold electron microscopy confirmed the association of NCC with the clathrin-mediated internalization pathway in rat DCT cells. Compared with controls, inducing phosphorylation of NCC via low chloride treatment or mimicking phosphorylation by replacing Thr-53, Thr-58, and Ser-71 residues with Asp resulted in increased membrane abundance and reduced rates of NCC internalization. NCC ubiquitylation was lowest in the conditions with greatest NCC phosphorylation, thus providing a mechanism for the reduced endocytosis. In conclusion, our data support a model where NCC is constitutively cycled to the plasma membrane, and upon stimulation, it can be phosphorylated to both increase NCC activity and decrease NCC endocytosis, together increasing NaCl transport in the DCT. PMID:24668812

Phosphorylation regulates NCC stability and transporter activity in vivo.

PubMed

Yang, Sung-Sen; Fang, Yu-Wei; Tseng, Min-Hua; Chu, Pei-Yi; Yu, I-Shing; Wu, Han-Chung; Lin, Shu-Wha; Chau, Tom; Uchida, Shinichi; Sasaki, Sei; Lin, Yuh-Feng; Sytwu, Huey-Kang; Lin, Shih-Hua

2013-10-01

A T60M mutation in the thiazide-sensitive sodium chloride cotransporter (NCC) is common in patients with Gitelman's syndrome (GS). This mutation prevents Ste20-related proline and alanine-rich kinase (SPAK)/oxidative stress responsive kinase-1 (OSR1)-mediated phosphorylation of NCC and alters NCC transporter activity in vitro. Here, we examined the physiologic effects of NCC phosphorylation in vivo using a novel Ncc T58M (human T60M) knock-in mouse model. Ncc(T58M/T58M) mice exhibited typical features of GS with a blunted response to thiazide diuretics. Despite expressing normal levels of Ncc mRNA, these mice had lower levels of total Ncc and p-Ncc protein that did not change with a low-salt diet that increased p-Spak. In contrast to wild-type Ncc, which localized to the apical membrane of distal convoluted tubule cells, T58M Ncc localized primarily to the cytosolic region and caused an increase in late distal convoluted tubule volume. In MDCK cells, exogenous expression of phosphorylation-defective NCC mutants reduced total protein expression levels and membrane stability. Furthermore, our analysis found diminished total urine NCC excretion in a cohort of GS patients with homozygous NCC T60M mutations. When Wnk4(D561A/+) mice, a model of pseudohypoaldosteronism type II expressing an activated Spak/Osr1-Ncc, were crossed with Ncc(T58M/T58M) mice, total Ncc and p-Ncc protein levels decreased and the GS phenotype persisted over the hypertensive phenotype. Overall, these data suggest that SPAK-mediated phosphorylation of NCC at T60 regulates NCC stability and function, and defective phosphorylation at this residue corrects the phenotype of pseudohypoaldosteronism type II.

Potassium intake modulates the thiazide-sensitive sodium-chloride cotransporter (NCC) activity via the Kir4.1 potassium channel.

PubMed

Wang, Ming-Xiao; Cuevas, Catherina A; Su, Xiao-Tong; Wu, Peng; Gao, Zhong-Xiuzi; Lin, Dao-Hong; McCormick, James A; Yang, Chao-Ling; Wang, Wen-Hui; Ellison, David H

2018-04-01

Kir4.1 in the distal convoluted tubule plays a key role in sensing plasma potassium and in modulating the thiazide-sensitive sodium-chloride cotransporter (NCC). Here we tested whether dietary potassium intake modulates Kir4.1 and whether this is essential for mediating the effect of potassium diet on NCC. High potassium intake inhibited the basolateral 40 pS potassium channel (a Kir4.1/5.1 heterotetramer) in the distal convoluted tubule, decreased basolateral potassium conductance, and depolarized the distal convoluted tubule membrane in Kcnj10flox/flox mice, herein referred to as control mice. In contrast, low potassium intake activated Kir4.1, increased potassium currents, and hyperpolarized the distal convoluted tubule membrane. These effects of dietary potassium intake on the basolateral potassium conductance and membrane potential in the distal convoluted tubule were completely absent in inducible kidney-specific Kir4.1 knockout mice. Furthermore, high potassium intake decreased, whereas low potassium intake increased the abundance of NCC expression only in the control but not in kidney-specific Kir4.1 knockout mice. Renal clearance studies demonstrated that low potassium augmented, while high potassium diminished, hydrochlorothiazide-induced natriuresis in control mice. Disruption of Kir4.1 significantly increased basal urinary sodium excretion but it abolished the natriuretic effect of hydrochlorothiazide. Finally, hypokalemia and metabolic alkalosis in kidney-specific Kir4.1 knockout mice were exacerbated by potassium restriction and only partially corrected by a high-potassium diet. Thus, Kir4.1 plays an essential role in mediating the effect of dietary potassium intake on NCC activity and potassium homeostasis. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

The Calcium-Sensing Receptor Increases Activity of the Renal NCC through the WNK4-SPAK Pathway.

PubMed

Bazúa-Valenti, Silvana; Rojas-Vega, Lorena; Castañeda-Bueno, María; Barrera-Chimal, Jonatan; Bautista, Rocío; Cervantes-Pérez, Luz G; Vázquez, Norma; Plata, Consuelo; Murillo-de-Ozores, Adrián R; González-Mariscal, Lorenza; Ellison, David H; Riccardi, Daniela; Bobadilla, Norma A; Gamba, Gerardo

2018-05-30

Background Hypercalciuria can result from activation of the basolateral calcium-sensing receptor (CaSR), which in the thick ascending limb of Henle's loop controls Ca 2+ excretion and NaCl reabsorption in response to extracellular Ca 2+ However, the function of CaSR in the regulation of NaCl reabsorption in the distal convoluted tubule (DCT) is unknown. We hypothesized that CaSR in this location is involved in activating the thiazide-sensitive NaCl cotransporter (NCC) to prevent NaCl loss. Methods We used a combination of in vitro and in vivo models to examine the effects of CaSR on NCC activity. Because the KLHL3-WNK4-SPAK pathway is involved in regulating NaCl reabsorption in the DCT, we assessed the involvement of this pathway as well. Results Thiazide-sensitive 22 Na + uptake assays in Xenopus laevis oocytes revealed that NCC activity increased in a WNK4-dependent manner upon activation of CaSR with Gd 3+ In HEK293 cells, treatment with the calcimimetic R-568 stimulated SPAK phosphorylation only in the presence of WNK4. The WNK4 inhibitor WNK463 also prevented this effect. Furthermore, CaSR activation in HEK293 cells led to phosphorylation of KLHL3 and WNK4 and increased WNK4 abundance and activity. Finally, acute oral administration of R-568 in mice led to the phosphorylation of NCC. Conclusions Activation of CaSR can increase NCC activity via the WNK4-SPAK pathway. It is possible that activation of CaSR by Ca 2+ in the apical membrane of the DCT increases NaCl reabsorption by NCC, with the consequent, well known decrease of Ca 2+ reabsorption, further promoting hypercalciuria. Copyright © 2018 by the American Society of Nephrology.

Aldosterone modulates thiazide-sensitive sodium chloride cotransporter abundance via DUSP6-mediated ERK1/2 signaling pathway

PubMed Central

Feng, Xiuyan; Zhang, Yiqian; Shao, Ningjun; Wang, Yanhui; Zhuang, Zhizhi; Wu, Ping; Lee, Matthew J.; Liu, Yingli; Wang, Xiaonan; Zhuang, Jieqiu; Delpire, Eric; Gu, Dingying

2015-01-01

Thiazide-sensitive sodium chloride cotransporter (NCC) plays an important role in maintaining blood pressure. Aldosterone is known to modulate NCC abundance. Previous studies reported that dietary salts modulated NCC abundance through either WNK4 [with no lysine (k) kinase 4]-SPAK (Ste20-related proline alanine-rich kinase) or WNK4-extracellular signal-regulated kinase-1 and -2 (ERK1/2) signaling pathways. To exclude the influence of SPAK signaling pathway on the role of the aldosterone-mediated ERK1/2 pathway in NCC regulation, we investigated the effects of dietary salt changes and aldosterone on NCC abundance in SPAK knockout (KO) mice. We found that in SPAK KO mice low-salt diet significantly increased total NCC abundance while reducing ERK1/2 phosphorylation, whereas high-salt diet decreased total NCC while increasing ERK1/2 phosphorylation. Importantly, exogenous aldosterone administration increased total NCC abundance in SPAK KO mice while increasing DUSP6 expression, an ERK1/2-specific phosphatase, and led to decreasing ERK1/2 phosphorylation without changing the ratio of phospho-T53-NCC/total NCC. In mouse distal convoluted tubule (mDCT) cells, aldosterone increased DUSP6 expression while reducing ERK1/2 phosphorylation. DUSP6 Knockdown increased ERK1/2 phosphorylation while reducing total NCC expression. Inhibition of DUSP6 by (E)-2-benzylidene-3-(cyclohexylamino)-2,3-dihydro-1H-inden-1-one increased ERK1/2 phosphorylation and reversed the aldosterone-mediated increments of NCC partly by increasing NCC ubiquitination. Therefore, these data suggest that aldosterone modulates NCC abundance via altering NCC ubiquitination through a DUSP6-dependent ERK1/2 signal pathway in SPAK KO mice and part of the effects of dietary salt changes may be mediated by aldosterone in the DCTs. PMID:25761881

Double Knockout of the Na+-Driven Cl−/HCO3− Exchanger and Na+/Cl− Cotransporter Induces Hypokalemia and Volume Depletion

PubMed Central

Sinning, Anne; Radionov, Nikita; Trepiccione, Francesco; López-Cayuqueo, Karen I.; Jayat, Maximilien; Baron, Stéphanie; Cornière, Nicolas; Alexander, R. Todd; Hadchouel, Juliette; Eladari, Dominique; Hübner, Christian A.

2017-01-01

We recently described a novel thiazide–sensitive electroneutral NaCl transport mechanism resulting from the parallel operation of the Cl−/HCO3− exchanger pendrin and the Na+–driven Cl−/2HCO3− exchanger (NDCBE) in β-intercalated cells of the collecting duct. Although a role for pendrin in maintaining Na+ balance, intravascular volume, and BP is well supported, there is no in vivo evidence for the role of NDCBE in maintaining Na+ balance. Here, we show that deletion of NDCBE in mice caused only subtle perturbations of Na+ homeostasis and provide evidence that the Na+/Cl− cotransporter (NCC) compensated for the inactivation of NDCBE. To unmask the role of NDCBE, we generated Ndcbe/Ncc double–knockout (dKO) mice. On a normal salt diet, dKO and single-knockout mice exhibited similar activation of the renin-angiotensin-aldosterone system, whereas only dKO mice displayed a lower blood K+ concentration. Furthermore, dKO mice displayed upregulation of the epithelial sodium channel (ENaC) and the Ca2+–activated K+ channel BKCa. During NaCl depletion, only dKO mice developed marked intravascular volume contraction, despite dramatically increased renin activity. Notably, the increase in aldosterone levels expected on NaCl depletion was attenuated in dKO mice, and single-knockout and dKO mice had similar blood K+ concentrations under this condition. In conclusion, NDCBE is necessary for maintaining sodium balance and intravascular volume during salt depletion or NCC inactivation in mice. Furthermore, NDCBE has an important role in the prevention of hypokalemia. Because NCC and NDCBE are both thiazide targets, the combined inhibition of NCC and the NDCBE/pendrin system may explain thiazide-induced hypokalemia in some patients. PMID:27151921

Reference values of renal tubular function tests are dependent on age and kidney function.

PubMed

Bech, Anneke P; Wetzels, Jack F M; Nijenhuis, Tom

2017-12-01

Electrolyte disorders due to tubular disorders are rare, and knowledge about validated clinical diagnostic tools such as tubular function tests is sparse. Reference values for tubular function tests are based on studies with small sample size in young healthy volunteers. Patients with tubular disorders, however, frequently are older and can have a compromised renal function. We therefore evaluated four tubular function tests in individuals with different ages and renal function. We performed furosemide, thiazide, furosemide-fludrocortisone, and desmopressin tests in healthy individuals aged 18-50 years, healthy individuals aged more than 50 years and individuals with compromised renal function. For each tubular function test we included 10 individuals per group. The responses in young healthy individuals were in line with previously reported values in literature. The maximal increase in fractional chloride excretion after furosemide was below the lower limit of young healthy individuals in 5/10 older subjects and in 2/10 patients with compromised renal function. The maximal increase in fractional chloride excretion after thiazide was below the lower limit of young healthy individuals in 6/10 older subjects and in 7/10 patients with compromised renal function. Median maximal urine osmolality after desmopressin was 1002 mosmol/kg H 2 O in young healthy individuals, 820 mosmol/kg H 2 O in older subjects and 624 mosmol/kg H 2 O in patients with compromised renal function. Reference values for tubular function tests obtained in young healthy adults thus cannot simply be extrapolated to older patients or patients with compromised kidney function. Larger validation studies are needed to define true reference values in these patient categories. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Genetic variation in renin predicts the effects of thiazide diuretics.

PubMed

Huang, Chin-Chou; Chung, Chia-Min; Hung, Shuen-Iu; Leu, Hsin-Bang; Wu, Tao-Cheng; Huang, Po-Hsun; Lin, Shing-Jong; Pan, Wen-Harn; Chen, Jaw-Wen

2011-08-01

While genetic variants of renin-angiotensin-aldosterone system (RAAS) may modify the blood pressure (BP) response to thiazide diuretics, there was no evidence of genetic variations in renin (REN) playing a role. This study aimed to address the potential effects of genetic variations of RAAS on the response to initial treatment of hydrochlorothiazide (HCTZ). We enrolled nondiabetic hypertensive patients with a systolic blood pressure (SBP) ≥140 or a diastolic blood pressure (DBP) ≥90mmHg, who were either previously untreated or unsatisfactorily treated. After lifestyle modification and diet instruction for 2weeks, 90 patients with persistently elevated BP were given HCTZ 50 mg every morning for 2 weeks. Single nucleotide polymorphism markers were selected from genes involving in RAAS, including rs7079 and rs699 of angiotensinogen, rs4293 and rs4353 of angiotensin-converting enzyme and rs1464816 and rs11240688 of REN. The patients were divided into three groups according to the SBP response after HCTZ. The upper 1/3 responders had older age (P=0·035), higher SBP (P=0·039), higher pulse pressure (P=0·006) and lower plasma REN activity (PRA) (P=0·020) when compared with the lower 1/3 responders. Renin rs11240688 CC polymorphism (β=9·931, corrected P=0·012), Log PRA (β=7·451, P=0·004) and baseline SBP (β=0·299, P=0·006) were the independent predictors for the BP lowering response. In addition to PRA, renin rs11240688 CC polymorphism may also independently predict the effect of HCTZ. © 2011 The Authors. European Journal of Clinical Investigation © 2011 Stichting European Society for Clinical Investigation Journal Foundation.

Characterization of constitutive and acid-induced outwardly rectifying chloride currents in immortalized mouse distal tubular cells.

PubMed

Valinsky, William C; Touyz, Rhian M; Shrier, Alvin

2017-08-01

Thiazides block Na + reabsorption while enhancing Ca 2+ reabsorption in the kidney. As previously demonstrated in immortalized mouse distal convoluted tubule (MDCT) cells, chlorothiazide application induced a robust plasma membrane hyperpolarization, which increased Ca 2+ uptake. This essential thiazide-induced hyperpolarization was prevented by the Cl - channel inhibitor 5-Nitro-2-(3-phenylpropylamino) benzoic acid (NPPB), implicating NPPB-sensitive Cl - channels, however the nature of these Cl - channels has been rarely described in the literature. Here we show that MDCT cells express a dominant, outwardly rectifying Cl - current at extracellular pH7.4. This constitutive Cl - current was more permeable to larger anions (Eisenman sequence I; I - >Br - ≥Cl - ) and was substantially inhibited by >100mM [Ca 2+ ] o , which distinguished it from ClC-K2/barttin. Moreover, the constitutive Cl - current was blocked by NPPB, along with other Cl - channel inhibitors (4,4'-diisothiocyanatostilbene-2,2'-disulfonate, DIDS; flufenamic acid, FFA). Subjecting the MDCT cells to an acidic extracellular solution (pH<5.5) induced a substantially larger outwardly rectifying NPPB-sensitive Cl - current. This acid-induced Cl - current was also anion permeable (I - >Br - >Cl - ), but was distinguished from the constitutive Cl - current by its rectification characteristics, ion sensitivities, and response to FFA. In addition, we have identified similar outwardly rectifying and acid-sensitive currents in immortalized cells from the inner medullary collecting duct (mIMCD-3 cells). Expression of an acid-induced Cl - current would be particularly relevant in the acidic IMCD (pH<5.5). To our knowledge, the properties of these Cl - currents are unique and provide the mechanisms to account for the Cl - efflux previously speculated to be present in MDCT cells. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Association of urinary citrate excretion, pH, and net gastrointestinal alkali absorption with diet, diuretic use, and blood glucose concentration.

PubMed

Perinpam, Majuran; Ware, Erin B; Smith, Jennifer A; Turner, Stephen T; Kardia, Sharon L R; Lieske, John C

2017-10-01

Urinary citrate (Ucit) protects against urinary stone formation. Acid base status and diet influence Ucit. However, the effect of demographics, diet, and glucose metabolism on Ucit excretion, urinary pH (U-pH) and net gastrointestinal alkali absorption (NAA) are not known. Twenty-four hour urine samples, blood glucose, creatinine, and cystatin C were obtained from non-Hispanic white sibships in Rochester, MN ( n  = 446; 64.5 ± 9 years; 58% female). Diet was assessed by a food frequency questionnaire. The impact of blood glucose, demographics and dietary elements on Ucit excretion, U-pH, and NAA were evaluated in bivariate and multivariable models and interaction models that included age, sex, and weight. NAA significantly associated with Ucit and U-pH In multivariate models Ucit increased with age, weight, eGFR C ys , and blood glucose, but decreased with loop diuretic and thiazide use. U-pH decreased with serum creatinine, blood glucose, and dietary protein but increased with dietary potassium. NAA was higher in males and increased with age, weight, eGFR C ys and dietary potassium. Significant interactions were observed for Ucit excretion with age and blood glucose, weight and eGFR C ys, and sex and thiazide use. Blood glucose had a significant and independent effect on U-pH and also Ucit. This study provides the first evidence that blood glucose could influence urinary stone risk independent of urinary pH, potentially providing new insight into the association of obesity and urinary stone disease. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Azilsartan/chlorthalidone combination therapy for blood pressure control

PubMed Central

Cheng, Judy WM

2013-01-01

Background Edarbyclor® is a combined angiotensin receptor blocker (ARB) and thiazide-like diuretic (azilsartan and chlorthalidone), and was approved on December 20, 2011 by the US Food and Drug Administration (FDA) for hypertension management. Objective To review the pharmacology, pharmacokinetics, efficacy, safety, tolerability, and role of azilsartan plus chlorthalidone for hypertension management. Methods Peer-reviewed clinical trials, review articles, and relevant treatment guidelines, were identified from the databases MEDLINE and Current Contents (both 1966 to February 15, 2013, inclusive) using search terms “azilsartan”, “chlorthalidone”, “pharmacology”, “pharmacokinetics”, “pharmacodynamics”, “pharmacoeconomics”, and “cost-effectiveness”. The FDA website, as well as manufacturer prescribing information, was also reviewed to identify other relevant information. Results Azilsartan is a new ARB with high affinity for the angiotensin 1 receptor, approved by the FDA for hypertension management. Unlike other ARBs, azilsartan has no clinical data supporting improvement in cardiovascular outcomes, and is not approved for indications other than hypertension, which a select few other ARBs may be used for (eg, diabetic nephropathy and heart failure). Chlorthalidone is a longer acting thiazide-like diuretic that has been demonstrated to improve cardiovascular outcomes. Combination treatment with azilsartan/chlorthalidone is effective for reducing blood pressure. Compared to olmesartan/hydrochlorothiazide and azilsartan/hydrochlorothiazide combinations, azilsartan/chlorthalidone appears to be more efficacious for reducing blood pressure. Conclusions Azilsartan/chlorthalidone can be considered an antihypertensive therapy option in patients for whom combination therapy is required (blood pressure >20 mmHg systolic or >10 mmHg diastolic above goal). Cost to patients and insurance coverage will probably determine whether azilsartan/chlorthalidone will be the most appropriate combination therapy for an individual patient. PMID:23807859

Quantifying intermolecular interactions in solid state indapamide and other popular diuretic drugs: Insights from Hirshfeld surface study

NASA Astrophysics Data System (ADS)

Bojarska, Joanna; Fruziński, Andrzej; Maniukiewicz, Waldemar

2016-07-01

Hirshfeld surfaces (HS) and two-dimensional fingerprint plots are used to analyze the intermolecular interactions in indapamide and other popular thiazide diuretic derivatives. The crystal structure of indapamide (INDP) at 100 K determined by single-crystal X-ray analysis, is also reported. The title compound crystallizes in the centrosymmetric I2/a space group with one indapamide and half water molecule (lying on the glide plane) in the asymmetric unit. An interplay of N-H⋯O hydrogen bonds connects the indapamide molecules generating chains with the graph-set motifs: C (8) and C23 (16), and together with C-H⋯O and π⋯π stacking interactions create a 3D net. The Hirshfeld surface study facilitates comparison of diverse and numerous intercontacts, such as H⋯H, O⋯H, Cl⋯H, C⋯C (π⋯π), C⋯O (π⋯lone pair), O⋯O (lone pair⋯lone pair), Cl⋯O, Cl⋯Cl, N⋯N, C⋯H (C-H⋯π) with regard to building self-assembled framework of indapamide and related thiazide derivatives retrieved from the Cambridge Structural Database. The HS analysis highlights that H⋯H, O⋯H/H⋯O and C⋯H/H⋯C contacts play an influential role contributing to about 80% of the HS areas in this class of compounds. Nevertheless, in the case of INDP the H⋯H interactions, while in hydrochlorothiazide (HCTZ) O⋯H/H⋯O are dominant amongst all intercontacts towards the HS. Notably, indapamide has the highest proportion of C⋯C contacts.

[Primary and secondary arterial hypertension - update 2016].

PubMed

Sanner, Bernd; Hausberg, Martin

2016-06-01

In patients with hypertension without diabetes and with an increased risk of cardiovascular complications a blood pressure of below 130 mmHg should be targeted. Hypertensive patients with an age above 80 years should be treated in the same way as younger hypertensive patients if they are otherwise healthy and functionally independent. On the other hand frail elderly patients could have an increased morbidity and mortality with intensive blood pressure control. In patients with resistant hypertension spironolactone was the most effective drug when given in addition to their baseline drugs (ACE-inhibitor/angiotensin receptor antagonist, calcium channel blocker and thiazide diuretic). © Georg Thieme Verlag KG Stuttgart · New York.

Familial microscopic hematuria caused by hypercalciuria and hyperuricosuria.

PubMed

Praga, M; Alegre, R; Hernández, E; Morales, E; Domínguez-Gil, B; Carreño, A; Andrés, A

2000-01-01

We report 12 patients belonging to five different families in whom persistent isolated microhematuria was associated with hypercalciuria and/or hyperuricosuria. Four patients had episodes of gross hematuria, three patients had passed renal stones, and a history of nephrolithiasis was obtained in four of the families (80%). Calcium oxalate and uric acid crystals were commonly observed in the urine sediments. Urinary erythrocytes had a normal appearance on phase-microscopic examination. Reduction of calciuria and uricosuria by thiazide diuretics, allopurinol, forced fluid intake, and dietetic measures led to a persistent normalization of urine sediment with complete disappearance of hematuria. Determination of calcium and uric acid urinary excretions should be included in the study of familial hematuria.

Effects of antihypertensive agents on sexual function.

PubMed

Weiss, R J

1991-12-01

Patient compliance with antihypertensive therapy can be improved by minimizing drug-induced sexual dysfunction. Impotence, decreased libido, impaired ejaculation and gynecomastia are potential side effects, depending on the agent prescribed. Centrally acting antihypertensive agents such as methyldopa and clonidine, nonselective beta-adrenergic blockers and potassium-sparing diuretics are the drugs most often associated with sexual dysfunction. Thiazide diuretics cause impotence but may otherwise play a minimal role in sexual dysfunction. Alpha-adrenergic blockers, angiotensin converting enzyme inhibitors and calcium channel blockers have little adverse effect on sexual function. It is important to obtain an adequate history before and after initiating therapy. If sexual dysfunction develops in a patient, a different class of medication can be tried.

[Why do good drugs disappear?].

PubMed

Brezis, Mayer; Tomer, Ron; Klang, Samuel; Hammerman, Ariel

2010-10-01

Old drugs, with proved efficacy and safety, are disappearing from the market. For instance, nitrofurantoin, an inexpensive effective agent for urinary tract infections with low incidence of bacterial resistance in comparison to other antibiotics, is becoming unavailable. Alpha-methyldopa and hydraLazine, drugs of choice for pregnancy hypertension, are no longer available. Chlorthalidone, a Long acting thiazide with best evidence on efficacy, is no Longer marketed in Israel. Switching to newer agents increases costs and is often associated with relative uncertainty about safety and efficacy. The reason for the disappearance of old drugs is a combination of market failures and failures in production and regulatory processes. System revisions are needed to allow continued availability of old, safe and effective drugs.

A case of gain-of-function mutation in calcium-sensing receptor: supplemental hydration is required for renal protection.

PubMed

Suzuki, M; Aso, T; Sato, T; Michimata, M; Kazama, I; Saiki, H; Hatano, R; Ejima, Y; Miyama, N; Sato, A; Matsubara, M

2005-06-01

The calcium-sensing receptor (CaSR) regulates the extracellular calcium level, mainly by controlling parathyroid hormon secretion and renal calcium reabsorption. In gain-of-function CaSR mutations, the genetic abnormalities increase CaSR activity leading to the development of such clinical manifestations as hypercalciuric hypocalcemia and hypoparathyroidism. We report a Japanese case of CaSR gain-of-function mutation and represent a therapeutic intervention based on the functional characteristics of CaSR in renal tubule. DNA sequence analysis revealed a heterozygous G to T mutation identified in a 12-year-old Japanese girl presenting with sporadic onset of hypercalciuric hypocalcemia and hypoparathyroidism. The mutation is located in the N-terminal extracellular domain of the CaSR gene, one of the most important parts for the three-dimensional construction of the receptor, resulting in the substitution of phenylalanine for cysteine at amino acid 131 (C131F) in exon 3. Based on the diagnosis of the gain-of-function mutation in the CaSR, oral hydrochlorothiazide administration and supplemental hydration were started in addition to calcium supplementation. The combination therapy of thiazide and supplemental hydration markedly reduced both renal calcium excretion and urinary calcium concentration from 0.4-0.7 to less than 0.1 mg/mg (urinary calcium/creatinine ratio) and from 10-15 to 3-5 mg/dl (urinary calcium concentration), respectively. This therapy stopped the progression of renal calcification during the follow-up period. Supplemental hydration should be considered essential for the following reasons: (1) calcium supplementation activates the CaSR in the kidney and suppresses renal urinary concentrating ability, (2) the thiazide has a diuretic effect, (3) as calcium supplementation increases renal calcium excretion, the supplemental hydration decreases urinary calcium concentration by increasing urinary volume, thereby diminishing the risk of intratubular crystallization of calcium ion.

Quantifying the effects of diuretics and β-adrenoceptor blockers on glycaemic control in diabetes mellitus - a systematic review and meta-analysis.

PubMed

Hirst, Jennifer A; Farmer, Andrew J; Feakins, Benjamin G; Aronson, Jeffrey K; Stevens, Richard J

2015-05-01

Although there are reports that β-adrenoceptor antagonists (beta-blockers) and diuretics can affect glycaemic control in people with diabetes mellitus, there is no clear information on how blood glucose concentrations may change and by how much. We report results from a systematic review to quantify the effects of these antihypertensive drugs on glycaemic control in adults with established diabetes. We systematically reviewed the literature to identify randomized controlled trials in which glycaemic control was studied in adults with diabetes taking either beta-blockers or diuretics. We combined data on HbA1c and fasting blood glucose using fixed effects meta-analysis. From 3864 papers retrieved, we found 10 studies of beta-blockers and 12 studies of diuretics to include in the meta-analysis. One study included both comparisons, totalling 21 included reports. Beta-blockers increased fasting blood glucose concentrations by 0.64 mmol l(-1) (95% CI 0.24, 1.03) and diuretics by 0.77 mmol l(-1) (95% CI 0.14, 1.39) compared with placebo. Effect sizes were largest in trials of non-selective beta-blockers (1.33, 95% CI 0.72, 1.95) and thiazide diuretics (1.69, 95% CI 0.60, 2.69). Beta-blockers increased HbA1c concentrations by 0.75% (95% CI 0.30, 1.20) and diuretics by 0.24% (95% CI -0.17, 0.65) compared with placebo. There was no significant difference in the number of hypoglycaemic events between beta-blockers and placebo in three trials. Randomized trials suggest that thiazide diuretics and non-selective beta-blockers increase fasting blood glucose and HbA1c concentrations in patients with diabetes by moderate amounts. These data will inform prescribing and monitoring of beta-blockers and diuretics in patients with diabetes. © 2014 The British Pharmacological Society.

Quantifying the effects of diuretics and β-adrenoceptor blockers on glycaemic control in diabetes mellitus – a systematic review and meta-analysis

PubMed Central

Hirst, Jennifer A; Farmer, Andrew J; Feakins, Benjamin G; Aronson, Jeffrey K; Stevens, Richard J

2015-01-01

Aims Although there are reports that β-adrenoceptor antagonists (beta-blockers) and diuretics can affect glycaemic control in people with diabetes mellitus, there is no clear information on how blood glucose concentrations may change and by how much. We report results from a systematic review to quantify the effects of these antihypertensive drugs on glycaemic control in adults with established diabetes. Methods We systematically reviewed the literature to identify randomized controlled trials in which glycaemic control was studied in adults with diabetes taking either beta-blockers or diuretics. We combined data on HbA1c and fasting blood glucose using fixed effects meta-analysis. Results From 3864 papers retrieved, we found 10 studies of beta-blockers and 12 studies of diuretics to include in the meta-analysis. One study included both comparisons, totalling 21 included reports. Beta-blockers increased fasting blood glucose concentrations by 0.64 mmol l−1 (95% CI 0.24, 1.03) and diuretics by 0.77 mmol l−1 (95% CI 0.14, 1.39) compared with placebo. Effect sizes were largest in trials of non-selective beta-blockers (1.33, 95% CI 0.72, 1.95) and thiazide diuretics (1.69, 95% CI 0.60, 2.69). Beta-blockers increased HbA1c concentrations by 0.75% (95% CI 0.30, 1.20) and diuretics by 0.24% (95% CI −0.17, 0.65) compared with placebo. There was no significant difference in the number of hypoglycaemic events between beta-blockers and placebo in three trials. Conclusions Randomized trials suggest that thiazide diuretics and non-selective beta-blockers increase fasting blood glucose and HbA1c concentrations in patients with diabetes by moderate amounts. These data will inform prescribing and monitoring of beta-blockers and diuretics in patients with diabetes. PMID:25377481

Systematic Review for the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines.

PubMed

Reboussin, David M; Allen, Norrina B; Griswold, Michael E; Guallar, Eliseo; Hong, Yuling; Lackland, Daniel T; Miller, Edgar Pete R; Polonsky, Tamar; Thompson-Paul, Angela M; Vupputuri, Suma

2018-06-01

To review the literature systematically and perform meta-analyses to address these questions: 1) Is there evidence that self-measured blood pressure (BP) without other augmentation is superior to office-based measurement of BP for achieving better BP control or for preventing adverse clinical outcomes that are related to elevated BP? 2) What is the optimal target for BP lowering during antihypertensive therapy in adults? 3) In adults with hypertension, how do various antihypertensive drug classes differ in their benefits and harms compared with each other as first-line therapy? Electronic literature searches were performed by Doctor Evidence, a global medical evidence software and services company, across PubMed and EMBASE from 1966 to 2015 using key words and relevant subject headings for randomized controlled trials that met eligibility criteria defined for each question. We performed analyses using traditional frequentist statistical and Bayesian approaches, including random-effects Bayesian network meta-analyses. Our results suggest that: 1) There is a modest but significant improvement in systolic BP in randomized controlled trials of self-measured BP versus usual care at 6 but not 12 months, and for selected patients and their providers self-measured BP may be a helpful adjunct to routine office care. 2) systolic BP lowering to a target of <130 mm Hg may reduce the risk of several important outcomes including risk of myocardial infarction, stroke, heart failure, and major cardiovascular events. No class of medications (ie, angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, calcium channel blockers, or beta blockers) was significantly better than thiazides and thiazide-like diuretics as a first-line therapy for any outcome. © 2017 by the American College of Cardiology Foundation and the American Heart Association, Inc.

Impact of Clinical Factors on the Achievement of Target Blood Pressure in Hypertensive Patients from Ivanovo Region of Russia: Data of 2015.

PubMed

Kiselev, A R; Posnenkova, O M; Belova, O A; Romanchuk, S V; Popova, Y V; Prokhorov, M D; Gridnev, V I

2017-12-01

In Russia, blood pressure (BP) control is below the optimal. The little is known about regional features and barriers to adequate BP control in Russian primary care. To evaluate the impact of clinical factors on achieving the target BP in hypertensive patients in one region of Russia. Retrospective medical data of 2015 on 11,129 patients (31.4% male) with hypertension (Htn) from Ivanovo region of Russia were examined. Achievement of target BP was assessed in all patients. We study association between BP control and clinical factors. 45.9% of studied patients with Htn had controlled BP. The frequency of achieving the target BP in subsets of hypertensive patients was 37.8% in patients with diabetes, 39.5% in patients with coronary artery disease, and 29.9% in patients with chronic heart failure. The main clinical factors associated with achieving the target BP in studied hypertensive patients were the advice on alcohol consumption, advice on smoking cessation, and advice on weight reduction. Therapy with main antihypertensive drugs (in particular, beta-blockers and thiazide diuretics) were also factors of optimal BP control in these patients. Comorbidities (chronic heart failure and cardiovascular diseases requiring the prescription of aspirin and statins) and family history of coronary artery disease were associated with inadequate BP control. A negative effect of some antihypertensive drugs (potassium sparing diuretics, ARBs, ACE-Is, and dihydropyridine CCBs) on BP control that was found out in our study requires further investigation. Other studied factors had no influence on BP control in patients with Htn from Ivanovo region. We identified regional factors of BP control in hypertensive patients from Ivanovo region of Russia. It is shown that individual medical education (in particular, medical advices) is the most important factor of optimal BP control. The intervention with antihypertensive therapy (beta-blockers and thiazide diuretics) facilitates the achievement of target BP. Comorbidity and age reduce the frequency of achieving the target BP.

Azilsartan medoxomil plus chlorthalidone reduces blood pressure more effectively than olmesartan plus hydrochlorothiazide in stage 2 systolic hypertension.

PubMed

Cushman, William C; Bakris, George L; White, William B; Weber, Michael A; Sica, Domenic; Roberts, Andrew; Lloyd, Eric; Kupfer, Stuart

2012-08-01

Azilsartan medoxomil, an effective, long-acting angiotensin II receptor blocker, is a new treatment for hypertension that is also being developed in fixed-dose combinations with chlorthalidone, a potent, long-acting thiazide-like diuretic. We compared once-daily fixed-dose combinations of azilsartan medoxomil/chlorthalidone force titrated to a high dose of either 40/25 mg or 80/25 mg with a fixed-dose combination of the angiotensin II receptor blocker olmesartan medoxomil plus the thiazide diuretic hydrochlorothiazide force titrated to 40/25 mg. The design was a randomized, 3-arm, double-blind, 12-week study of 1071 participants with baseline clinic systolic blood pressure 160 to 190 mm Hg and diastolic blood pressure ≤119 mm Hg. Patients had a mean age of 57 years; 59% were men, 73% were white, and 22% were black. At baseline, mean clinic blood pressure was 165/96 mm Hg and 24-hour mean blood pressure was 150/88 mm Hg. Changes in clinic (primary end point) and ambulatory systolic blood pressures at week 12 were significantly greater in both azilsartan medoxomil/chlorthalidone arms than in the olmesartan/hydrochlorothiazide arm (P<0.001). Changes in clinic systolic blood pressure (mean±SE) were -42.5±0.8, -44.0±0.8, and -37.1±0.8 mm Hg, respectively. Changes in 24-hour ambulatory systolic blood pressure were -33.9±0.8, -36.3±0.8, and -27.5±0.8 mm Hg, respectively. Adverse events leading to permanent drug discontinuation occurred in 7.9%, 14.5%, and 7.1% of the groups given azilsartan medoxomil/chlorthalidone 40/25 mg, azilsartan medoxomil/chlorthalidone 80/25 mg, and olmesartan/hydrochlorothiazide 40/25 mg, respectively. This large, forced-titration study has demonstrated superior antihypertensive efficacy of azilsartan medoxomil/chlorthalidone fixed-dose combinations compared with the maximum approved dose of olmesartan/hydrochlorothiazide.

Shifting trends in the pharmacologic treatment of hypertension in a Nigerian tertiary hospital: a real-world evaluation of the efficacy, safety, rationality and pharmaco-economics of old and newer antihypertensive drugs.

PubMed

Adigun, A Q; Ishola, D A; Akintomide, A O; Ajayi, A A L

2003-04-01

The current prescription patterns for essential hypertension and the efficacy, safety, tolerability and cost-effectiveness of the newer antihypertensive drugs were evaluated in Nigerian patients. The findings were compared with that of a previous study conducted in the same tertiary hospital 10 years earlier. A cross-sectional evaluation of blood pressure (BP) control in a hypertension clinic was undertaken among 150 Nigerian patients aged 61 +/- 12 years (55% females), with a duration of treatment on a particular drug class or combination of 9 +/- 3 months. The initial blood pressure was 176 +/- 20/108 +/- 11 mmHg and 22% of the patient had concurrent diabetes mellitus. Thiazide diuretics (D) alone or in combination remained the most commonly prescribed drugs in 56% of all patients. There were significant increases in the prescriptions of calcium channel blockers (CCBs) (51%), P < 0.0001, and ACE-inhibitors (ACEIs) (24%), P < 0.0001, but a slight reduction in the use of methyldopa, and fixed drug combinations (P < 0.01) compared to the previous study. The fall in systolic blood pressure on D (r = 0.65, P < 0.001) or CCB (r = 0.48, P < 0.02) was significantly correlated with the initial systolic blood pressure, but not age. More patients achieved normotension BP < 140/90 mmHg on CCB monotherapy (71%), than D monotherapy (56%). Combination therapy with ACEIs + D or methyldopa+thiazides normalized BP in 63 and 68%, respectively. Pulse pressure, a surrogate marker for cardiovascular complications and mortality in essential hypertension, was significantly reduced (P < 0.01) equally by all treatments, with 95% confidence intervals ranging from -28 to -1 mmHg. However, hypertensive-diabetic (HT-DM) patients (n = 33) exhibited no significant change in pulse pressure in response to treatment. Adverse drug reactions that occurred in 11% were impotence or postural dizziness with D, headache and pitting oedema with CCB, and dry cough with ACEI. Pharmaco-economic comparison of the drug classes revealed that for every US dollar (dollar) spent per month, the percentage of treated patients attaining normotension was 18.6 for D, 4.73 for CCB, 3.5 for ACEI + D and 13.6 for methyldopa + thiazides. A combination of ACEI + CCB or D was the preferred treatment for hypertensive-diabetic Nigerians, but only 24% attained a BP < 130/85 mmHg. These results demonstrate a shift in trend to a more rational and efficacious treatment of hypertension over a 10 year period. This may be associated, at least in part, with the intensive and continuous education of the prescribers in rational drug use and the introduction of a hospital formulary. Methyldopa is still a highly efficacious and cost-effective drug in this population. Black HT-DM Africans still constitute a subgroup who not only require more and costlier antihypertensive drugs, but whose BP control is suboptimal, and exhibit a poor therapeutic response to other risk factors (pulse pressure) that constitute a continuing risk for cardiovascular mortality.

Evaluation of indoramin added to oxprenolol and bendrofluazide as a third agent in severe hypertension.

PubMed

Marshall, A J; Kettle, M A; Barritt, D W

1980-09-01

1 Indoramin, an alpha-adrenoreceptor blocking agent has been given as a third agent to patients with severe hypertension treated with adequate doses of a beta-adrenoceptor blocking drug and a thiazide diuretic. 2 A further fall in blood pressure followed the addition of indoramin. With 75 mg twice daily this was on average a fall of 12% of mean arterial pressure in the supine position, 16% standing an 17% after exercise. 3 The rise in blood pressure caused by isometric exercise was not altered by indoramin. 4 Indoramin slowed the heart rate. On 75 mg twice daily the reduction was 14% at rest and 19% after exercise. 5 Side effects of indoramin were sedation, sleep disturbance and vivid dreams.

Acute and Chronic Cardiovascular Effects of Hyperkalemia: New Insights Into Prevention and Clinical Management.

PubMed

Krishnan, Sandeep K; Lepor, Norman E

2016-01-01

Hyperkalemia is a common electrolyte disorder associated with life-threatening cardiac arrhythmias and increased mortality. Patients at greatest risk for hyperkalemia include those with diabetes and those with impaired renal function in whom a defect in the excretion of renal potassium may already exist. Hyperkalemia is likely to become more common clinically because angiotensin receptor blockers and angiotensin-converting enzyme inhibitors are increasingly being used in higher doses and are thought to confer cardiovascular and renal protection. Until recently, options for treating hyperkalemia were limited to the use of thiazide and loop diuretics and sodium polystyrene sulfonate. Newer options such as sodium zirconium cyclosilicate will allow for the safe and effective treatment of hyperkalemia while maintaining patients on prescribed renin-angiotensin-aldosterone system inhibitors.

Systematic Review for the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines.

PubMed

Reboussin, David M; Allen, Norrina B; Griswold, Michael E; Guallar, Eliseo; Hong, Yuling; Lackland, Daniel T; Miller, Edgar Pete R; Polonsky, Tamar; Thompson-Paul, Angela M; Vupputuri, Suma

2018-05-15

To review the literature systematically and perform meta-analyses to address these questions: 1) Is there evidence that self-measured blood pressure (BP) without other augmentation is superior to office-based measurement of BP for achieving better BP control or for preventing adverse clinical outcomes that are related to elevated BP? 2) What is the optimal target for BP lowering during antihypertensive therapy in adults? 3) In adults with hypertension, how do various antihypertensive drug classes differ in their benefits and harms compared with each other as first-line therapy? Electronic literature searches were performed by Doctor Evidence, a global medical evidence software and services company, across PubMed and EMBASE from 1966 to 2015 using key words and relevant subject headings for randomized controlled trials that met eligibility criteria defined for each question. We performed analyses using traditional frequentist statistical and Bayesian approaches, including random-effects Bayesian network meta-analyses. Our results suggest that: 1) There is a modest but significant improvement in systolic BP in randomized controlled trials of self-measured BP versus usual care at 6 but not 12 months, and for selected patients and their providers self-measured BP may be a helpful adjunct to routine office care. 2) systolic BP lowering to a target of <130 mm Hg may reduce the risk of several important outcomes including risk of myocardial infarction, stroke, heart failure, and major cardiovascular events. No class of medications (i.e., angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, calcium channel blockers, or beta blockers) was significantly better than thiazides and thiazide-like diuretics as a first-line therapy for any outcome. Copyright © 2018 American College of Cardiology Foundation and the American Heart Association, Inc. Published by Elsevier Inc. All rights reserved.

South African hypertension guideline 2011.

PubMed

Seedat, Y K; Rayner, B L

2011-12-14

Extensive data from randomised controlled trials have shown the benefit of treating hypertension. The target blood pressure (BP) for antihypertensive management is systolic <140 mmHg and diastolic <90 mmHg with minimal or no drug side-effects; however, stricter BP control is required for patients with end-organ damage, co-existing risk factors and co-morbidity, e.g. diabetes mellitus. The reduction of BP in the elderly and in those with severe hypertension should be achieved gradually over 1 month. Co-existent risk factors should also be controlled. Benefits of management include reduced risks of stroke, cardiac failure, chronic kidney disease and coronary heart disease. The correct BP measurement procedure is described, and evaluation of cardiovascular risk factors and recommendations for antihypertensive therapy are stipulated. The total cardiovascular disease risk profile should be determined for all patients to inform management strategies. Lifestyle modification and patient education are cornerstones in the management of every patient. Major indications, precautions and contra-indications to each recommended antihypertensive drug are listed. Combination therapy should be considered ab initio if the BP is ≥ 20/10 mmHg. First-line drug therapy for uncomplicated hypertension includes low-dose thiazide-like diuretics, calcium channel blockers (CCBs) or angiotensin-converting enzyme inhibitors (ACE-Is) (or ARBs - angiotensin II receptor blockers). If the target BP is not obtained, a second antihypertensive should be added from the aforementioned list. If the target BP is still not met, the third remaining antihypertensive agent should be used. In black patients either thiazide-like diuretics or CCBs can be used initially, because response rates are better than with ACE-Is or β-blockers. In treating resistant hypertension, a centrally acting drug, vasodilator, α-blocker, spironolactone or β-locker should be added. This guideline includes management of specific situations, i.e. hypertensive emergency and urgency, severe hypertension with target organ damage, hypertension in diabetes mellitus, resistant hypertension, fixed drug combinations, new trials in hypertension, and interactions of antihypertensive agents with other drugs. The guideline was developed by the Southern African Hypertension Society.

Lithium fluxes indicate presence of Na-Cl cotransport (NCC) in human lens epithelial cells.

PubMed

Lauf, Peter K; Chimote, Ameet A; Adragna, Norma C

2008-01-01

During regulatory volume decrease (RVD) of human lens epithelial cells (hLECs) by clotrimazole (CTZ)-sensitive K fluxes, Na-K-2Cl cotransport (NKCC) remains active and K-Cl cotransport (KCC) inactive. To determine whether such an abnormal behavior was caused by RVD-induced cell shrinkage, NKCC was measured in the presence of either CTZ or in high K media to prevent RVD. NKCC transports RbCl + NaCl, and LiCl + KCl; thus ouabain-insensitive, bumetanide-sensitive (BS) or Cl-dependent (ClD) Rb and Li fluxes were determined in hyposmotic high NaCl media with CTZ, or in high KCl media alone, or with sulfamate (Sf) or nitrate as Cl replacement at varying Rb, Li or Cl mol fractions (MF). Unexpectedly, NKCC was inhibited by 80% with CTZ (IC(50) = 31 microM). In isosmotic (300 mOsM) K, Li influx was approximately 1/3 of Rb influx in Na, 50% lower in Sf, and bumetanide-insensitive (BI). In hypotonic (200 mOsM) K, only the ClD but not BS Li fluxes were detected. At Li MFs from 0.1-1, Li fluxes fitted a bell-shaped curve maxing at approximately 0.6 Li MF, with the BS fluxes equaling approximately 1/4 of the ClD-Li influx. The difference, i.e. the BI/ClD Li influx, saturated with increasing Li and Cl MFs, with K(ms) for Li of 11 with, and 7 mM without K, and of approximately 46 mM for Cl. Inhibition of this K-independent Li influx by thiazides was weak whilst furosemide (<100 microM) was ineffective. Reverse transcription polymerase chain reaction and Western blots verified presence of both NKCC1 and Na-Cl cotransport (NCC). In conclusion, in hyposmotic high K media, which prevents CTZ-sensitive K flux-mediated RVD in hLECs, NKCC1, though molecularly expressed, was functionally silent. However, a K-independent and moderately thiazide-sensitive ClD-Li flux, i.e. LiCC, likely occurring through NCC was detected operationally and molecularly. (c) 2008 S. Karger AG, Basel.

Number of daily antihypertensive drugs and the risk of osteoporotic fractures in older hypertensive adults: National health insurance service - Senior cohort.

PubMed

Kim, So Yeon; Kim, Sunyoung; Choi, Sung Eun; Kim, Byung Sung; Choi, Hyun Rim; Hwang, Deri; Won, Chang Won

2017-07-01

Antihypertensive medication represents one of the most common prescriptions for senior individuals. Numerous studies have assessed the influence of antihypertensive treatment on the risk for osteoporotic fracture, yet much controversy remains. We analyzed the relationship between the incidence of osteoporotic fracture and the average number of daily antihypertensive drugs (NDAD) included in the prescription of elderly hypertensive patients. The study population was derived from the National Health Insurance Service-Senior Cohort (2002-2013), and consisted of elderly patients (≥60 years) diagnosed with hypertension in 2009, who did not have osteoporotic fractures in 2008, and underwent at least one national health check-up between 2009 and 2013, and had complete records after 2010. The outcome measured was the incidence of osteoporotic fractures between 2010 and 2013. The study population was stratified into the three groups (low, moderate, and high), in terms of NDAD. A total of 137,304 hypertensive patients were included. A multivariate model corrected by age, gender, body mass index, systolic blood pressure, underlying disease, smoking status, and use of medicines showed that the groups with moderate and high NDAD exhibited, respectively, 12% and 16% lower risk of osteoporotic fracture compared to that in the group with low NDAD. In terms of the risk of osteoporotic fracture associated with the number of daily thiazide diuretics (NDTD), the adjusted odds ratios (aOR; 95%CI) were 0.89 (0.84-0.94) and 0.93 (0.84-1.02) in the groups with moderate and high NDTD, respectively compared to low NDTD as reference. As to NDADnotTD, the aOR (95%CI) were 0.90 (95%CI, 0.86-0.94) and 0.89 (95%CI, 0.84-0.95) in the groups with moderate and high NDADnotTD, respectively compared to low NDADnotTD as reference. In elderly hypertensive patients, the incidence of osteoporotic fracture decreased as the NDAD increased. The incidence rate of osteoporotic fracture also decreased with the increase in the number of daily non-thiazide antihypertensive drugs. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

The 2010 Canadian Hypertension Education Program recommendations for the management of hypertension: part 2 - therapy.

PubMed

Hackam, Daniel G; Khan, Nadia A; Hemmelgarn, Brenda R; Rabkin, Simon W; Touyz, Rhian M; Campbell, Norman R C; Padwal, Raj; Campbell, Tavis S; Lindsay, M Patrice; Hill, Michael D; Quinn, Robert R; Mahon, Jeff L; Herman, Robert J; Schiffrin, Ernesto L; Ruzicka, Marcel; Larochelle, Pierre; Feldman, Ross D; Lebel, Marcel; Poirier, Luc; Arnold, J Malcolm O; Moe, Gordon W; Howlett, Jonathan G; Trudeau, Luc; Bacon, Simon L; Petrella, Robert J; Milot, Alain; Stone, James A; Drouin, Denis; Boulanger, Jean-Martin; Sharma, Mukul; Hamet, Pavel; Fodor, George; Dresser, George K; Carruthers, S George; Pylypchuk, George; Burgess, Ellen D; Burns, Kevin D; Vallée, Michel; Prasad, G V Ramesh; Gilbert, Richard E; Leiter, Lawrence A; Jones, Charlotte; Ogilvie, Richard I; Woo, Vincent; McFarlane, Philip A; Hegele, Robert A; Tobe, Sheldon W

2010-05-01

To update the evidence-based recommendations for the prevention and treatment of hypertension in adults for 2010. For lifestyle and pharmacological interventions, randomized trials and systematic reviews of trials were preferentially reviewed. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. However, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the general lack of long-term morbidity and mortality data in this field. Progressive renal impairment was also accepted as a clinically relevant primary outcome among patients with chronic kidney disease. A Cochrane Collaboration librarian conducted an independent MEDLINE search from 2008 to August 2009 to update the 2009 recommendations. To identify additional studies, reference lists were reviewed and experts were contacted. All relevant articles were reviewed and appraised independently by both content and methodological experts using prespecified levels of evidence. For lifestyle modifications to prevent and treat hypertension, restrict dietary sodium to 1500 mg (65 mmol) per day in adults 50 years of age or younger, to 1300 mg (57 mmol) per day in adults 51 to 70 years of age, and to 1200 mg (52 mmol) per day in adults older than 70 years of age; perform 30 min to 60 min of moderate aerobic exercise four to seven days per week; maintain a healthy body weight (body mass index 18.5 kg/m(2) to 24.9 kg/m(2)) and waist circumference (less than 102 cm for men and less than 88 cm for women); limit alcohol consumption to no more than 14 standard drinks per week for men or nine standard drinks per week for women; follow a diet that emphasizes fruits, vegetables and low-fat dairy products, dietary and soluble fibre, whole grains and protein from plant sources, and that is low in saturated fat and cholesterol; and consider stress management in selected individuals with hypertension. For the pharmacological management of hypertension, treatment thresholds and targets should be predicated on the patient's global atherosclerotic risk, target organ damage and comorbid conditions. Blood pressure should be decreased to less than 140/90 mmHg in all patients, and to less than 130/80 mmHg in patients with diabetes mellitus or chronic kidney disease. Most patients will require more than one agent to achieve these target blood pressures. Antihypertensive therapy should be considered in all adult patients regardless of age (caution should be exercised in elderly patients who are frail). For adults without compelling indications for other agents, considerations for initial therapy should include thiazide diuretics, angiotensin- converting enzyme (ACE) inhibitors (in patients who are not black), long-acting calcium channel blockers (CCBs), angiotensin receptor blockers (ARBs) or beta-blockers (in those younger than 60 years of age). A combination of two first-line agents may also be considered as initial treatment of hypertension if systolic blood pressure is 20 mmHg above target or if diastolic blood pressure is 10 mmHg above target. The combination of ACE inhibitors and ARBs should not be used, unless compelling indications are present to suggest consideration of dual therapy. Agents appropriate for first-line therapy for isolated systolic hypertension include thiazide diuretics, long-acting dihydropyridine CCBs or ARBs. In patients with coronary artery disease, ACE inhibitors, ARBs or betablockers are recommended as first-line therapy; in patients with cerebrovascular disease, an ACE inhibitor/diuretic combination is preferred; in patients with proteinuric nondiabetic chronic kidney disease, ACE inhibitors or ARBs (if intolerant to ACE inhibitors) are recommended; and in patients with diabetes mellitus, ACE inhibitors or ARBs (or, in patients without albuminuria, thiazides or dihydropyridine CCBs) are appropriate first-line therapies. In selected high-risk patients in whom combination therapy is being considered, an ACE inhibitor plus a long-acting dihydropyridine CCB is preferable to an ACE inhibitor plus a thiazide diuretic. All hypertensive patients with dyslipidemia should be treated using the thresholds, targets and agents outlined in the Canadian lipid treatment guidelines. Selected patients with hypertension who do not achieve thresholds for statin therapy, but who are otherwise at high risk for cardiovascular events, should nonetheless receive statin therapy. Once blood pressure is controlled, low-dose acetylsalicylic acid therapy should be considered. All recommendations were graded according to the strength of the evidence and voted on by the 63 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 80% consensus. These guidelines will continue to be updated annually. The Canadian Hypertension Education Program process is sponsored by the Canadian Hypertension Society, Blood Pressure Canada, the Public Health Agency of Canada, the College of Family Physicians of Canada, the Canadian Pharmacists Association, the Canadian Council of Cardiovascular Nurses, and the Heart and Stroke Foundation of Canada.

The 2010 Canadian Hypertension Education Program recommendations for the management of hypertension: Part 2 – therapy

PubMed Central

Hackam, Daniel G; Khan, Nadia A; Hemmelgarn, Brenda R; Rabkin, Simon W; Touyz, Rhian M; Campbell, Norman RC; Padwal, Raj; Campbell, Tavis S; Lindsay, M Patrice; Hill, Michael D; Quinn, Robert R; Mahon, Jeff L; Herman, Robert J; Schiffrin, Ernesto L; Ruzicka, Marcel; Larochelle, Pierre; Feldman, Ross D; Lebel, Marcel; Poirier, Luc; Arnold, J Malcolm O; Moe, Gordon W; Howlett, Jonathan G; Trudeau, Luc; Bacon, Simon L; Petrella, Robert J; Milot, Alain; Stone, James A; Drouin, Denis; Boulanger, Jean-Martin; Sharma, Mukul; Hamet, Pavel; Fodor, George; Dresser, George K; Carruthers, S George; Pylypchuk, George; Burgess, Ellen D; Burns, Kevin D; Vallée, Michel; Prasad, GV Ramesh; Gilbert, Richard E; Leiter, Lawrence A; Jones, Charlotte; Ogilvie, Richard I; Woo, Vincent; McFarlane, Philip A; Hegele, Robert A; Tobe, Sheldon W

2010-01-01

OBJECTIVE: To update the evidence-based recommendations for the prevention and treatment of hypertension in adults for 2010. OPTIONS AND OUTCOMES: For lifestyle and pharmacological interventions, randomized trials and systematic reviews of trials were preferentially reviewed. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. However, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the general lack of long-term morbidity and mortality data in this field. Progressive renal impairment was also accepted as a clinically relevant primary outcome among patients with chronic kidney disease. EVIDENCE: A Cochrane Collaboration librarian conducted an independent MEDLINE search from 2008 to August 2009 to update the 2009 recommendations. To identify additional studies, reference lists were reviewed and experts were contacted. All relevant articles were reviewed and appraised independently by both content and methodological experts using prespecified levels of evidence. RECOMMENDATIONS: For lifestyle modifications to prevent and treat hypertension, restrict dietary sodium to 1500 mg (65 mmol) per day in adults 50 years of age or younger, to 1300 mg (57 mmol) per day in adults 51 to 70 years of age, and to 1200 mg (52 mmol) per day in adults older than 70 years of age; perform 30 min to 60 min of moderate aerobic exercise four to seven days per week; maintain a healthy body weight (body mass index 18.5 kg/m2 to 24.9 kg/m2) and waist circumference (less than 102 cm for men and less than 88 cm for women); limit alcohol consumption to no more than 14 standard drinks per week for men or nine standard drinks per week for women; follow a diet that emphasizes fruits, vegetables and low-fat dairy products, dietary and soluble fibre, whole grains and protein from plant sources, and that is low in saturated fat and cholesterol; and consider stress management in selected individuals with hypertension. For the pharmacological management of hypertension, treatment thresholds and targets should be predicated on the patient’s global atherosclerotic risk, target organ damage and comorbid conditions. Blood pressure should be decreased to less than 140/90 mmHg in all patients, and to less than 130/80 mmHg in patients with diabetes mellitus or chronic kidney disease. Most patients will require more than one agent to achieve these target blood pressures. Antihypertensive therapy should be considered in all adult patients regardless of age (caution should be exercised in elderly patients who are frail). For adults without compelling indications for other agents, considerations for initial therapy should include thiazide diuretics, angiotensin-converting enzyme (ACE) inhibitors (in patients who are not black), long-acting calcium channel blockers (CCBs), angiotensin receptor blockers (ARBs) or beta-blockers (in those younger than 60 years of age). A combination of two first-line agents may also be considered as initial treatment of hypertension if systolic blood pressure is 20 mmHg above target or if diastolic blood pressure is 10 mmHg above target. The combination of ACE inhibitors and ARBs should not be used, unless compelling indications are present to suggest consideration of dual therapy. Agents appropriate for first-line therapy for isolated systolic hypertension include thiazide diuretics, long-acting dihydropyridine CCBs or ARBs. In patients with coronary artery disease, ACE inhibitors, ARBs or beta-blockers are recommended as first-line therapy; in patients with cerebrovascular disease, an ACE inhibitor/diuretic combination is preferred; in patients with proteinuric nondiabetic chronic kidney disease, ACE inhibitors or ARBs (if intolerant to ACE inhibitors) are recommended; and in patients with diabetes mellitus, ACE inhibitors or ARBs (or, in patients without albuminuria, thiazides or dihydropyridine CCBs) are appropriate first-line therapies. In selected high-risk patients in whom combination therapy is being considered, an ACE inhibitor plus a long-acting dihydropyridine CCB is preferable to an ACE inhibitor plus a thiazide diuretic. All hypertensive patients with dyslipidemia should be treated using the thresholds, targets and agents outlined in the Canadian lipid treatment guidelines. Selected patients with hypertension who do not achieve thresholds for statin therapy, but who are otherwise at high risk for cardiovascular events, should nonetheless receive statin therapy. Once blood pressure is controlled, low-dose acetylsalicylic acid therapy should be considered. VALIDATION: All recommendations were graded according to the strength of the evidence and voted on by the 63 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 80% consensus. These guidelines will continue to be updated annually. SPONSORS: The Canadian Hypertension Education Program process is sponsored by the Canadian Hypertension Society, Blood Pressure Canada, the Public Health Agency of Canada, the College of Family Physicians of Canada, the Canadian Pharmacists Association, the Canadian Council of Cardiovascular Nurses, and the Heart and Stroke Foundation of Canada. PMID:20485689

Diuretics in acute kidney injury.

PubMed

Nigwekar, Sagar U; Waikar, Sushrut S

2011-11-01

Acute kidney injury (AKI) is common in hospitalized patients and is associated with significant morbidity and mortality. The incidence of AKI is increasing and despite clinical advances there has been little change in the outcomes associated with AKI. A variety of interventions, including loop diuretics, have been tested for the prevention and treatment of AKI; however, none to date have shown convincing benefits in clinical studies, and the management of AKI remains largely supportive. In this article, we review the pharmacology and experimental and clinical evidence for loop diuretics in the management of AKI. In addition, we also review evidence for other agents with diuretic and/or natriuretic properties such as thiazide diuretics, mannitol, fenoldopam, and natriuretic peptides in both the prevention and treatment of AKI. Implications for current clinical practice are outlined to guide clinical decisions in this field. Copyright © 2011 Elsevier Inc. All rights reserved.

A case of Gitelman syndrome with severe hyponatraemia and hypophosphataemia.

PubMed

Ali, Absar; Masood, Qamar; Yaqub, Sonia; Kashif, Waqar

2013-01-01

Gitelman syndrome (GS) is a renal tubular disorder of the thiazide-sensitive sodium chloride cotransporter, which is located in the distal tubule of the loop of Henle. We present a rare case of GS complicated by severe hyponatraemia and hypophosphataemia. A 17-year-old boy was admitted to our institution with fever and lethargy. The workup revealed typical features of GS, i.e. hypokalaemia, hypomagnesaemia and metabolic alkalosis. In this report, we discuss the differential diagnoses and rationale for accepting GS as the most likely diagnosis. This case was complicated by severe hyponatraemia (115 mmol/L) and hypophosphataemia (0.32 mmol/L). We concluded that the syndrome of inappropriate secretion of antidiuretic hormones could not be ruled out and that respiratory alkalosis was the most likely aetiology of hypophosphataemia. This case report also generates an interesting discussion on water and electrolyte metabolism.

Regulation of blood pressure and renal function by NCC and ENaC: lessons from genetically engineered mice.

PubMed

Verouti, Sophia N; Boscardin, Emilie; Hummler, Edith; Frateschi, Simona

2015-04-01

The activity of the thiazide-sensitive Na(+)/Cl(-) cotransporter (NCC) and of the amiloride-sensitive epithelial Na(+) channel (ENaC) is pivotal for blood pressure regulation. NCC is responsible for Na(+) reabsorption in the distal convoluted tubule (DCT) of the nephron, while ENaC reabsorbs the filtered Na(+) in the late DCT and in the cortical collecting ducts (CCD) providing the final renal adjustment to Na(+) balance. Here, we aim to highlight the recent advances made using transgenic mouse models towards the understanding of the regulation of NCC and ENaC function relevant to the control of sodium balance and blood pressure. We thus like to pave the way for common mechanisms regulating these two sodium-transporting proteins and their potential implication in structural remodeling of the nephron segments and Na(+) and Cl(-) reabsorption. Copyright © 2015 Elsevier Ltd. All rights reserved.

Regulation of the renal Na+-Cl− cotransporter by phosphorylation and ubiquitylation

PubMed Central

2012-01-01

The activity of the renal thiazide-sensitive NaCl cotransporter (NCC) in the distal convoluted tubule plays a key role in defining arterial blood pressure levels. Increased or decreased activity of the NCC is associated with arterial hypertension or hypotension, respectively. Thus it is of major interest to understand the activity of NCC using in vivo models. Phosphorylation of certain residues of the amino-terminal domain of NCC has been shown to be associated with its activation. The development of phospho-specific antibodies against these sites provides a powerful tool that is helping to increase our understanding of the molecular physiology of NCC. Additionally, NCC expression in the plasma membrane is modulated by ubiquitylation, which represents another major mechanism for regulating protein activity. This work presents a review of our current knowledge of the regulation of NCC activity by phosphorylation and ubiquitylation. PMID:23034942

[Menopause: Hypertension and vascular disease].

PubMed

Zilberman, J M

Hypertension is the main cardiovascular risk factor affecting 25% of women. Hormone changes and hypertension after menopause may lead to higher target organ damage and cardiovascular disease such as increased arterial stiffness, coronary diseases, chronic heart failure and stroke. The physiopathological mechanisms involved in the development of hypertension and cardiovascular diseases in menopausal women are controversial. There are pharmacokinetic and pharmacodynamic differences in both sexes, the women have more coughing when using the converting-enzyme inhibitors, more cramps when using thiazide diuretics and more oedema in the inferior limbs when using calcium antagonists. The aim of this review is to analyse possible physiopathological mechanisms involved in hypertension after menopause and to gain a better understanding of the biological effects mediated by vascular ageing in women when the level of oestrogen protective effect decreases over the vascular system. Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

Potassium Modulates Electrolyte Balance and Blood Pressure through Effects on Distal Cell Voltage and Chloride

PubMed Central

Terker, Andrew S.; Zhang, Chong; McCormick, James A.; Lazelle, Rebecca A.; Zhang, Chengbiao; Meermeier, Nicholas P.; Siler, Dominic A.; Park, Hae J.; Fu, Yi; Cohen, David M.; Weinstein, Alan M.; Wang, Wen-Hui; Yang, Chao-Ling; Ellison, David H.

2015-01-01

SUMMARY Dietary potassium deficiency, common in Western diets, raises blood pressure and enhances salt sensitivity. Potassium homeostasis requires a molecular switch in the distal convoluted tubule (DCT), which fails in familial hyperkalemic hypertension (pseudohypoaldosteronism type 2), activating the thiazide-sensitive NaCl cotransporter, NCC. Here, we show that dietary potassium deficiency activates NCC, even in the setting of high salt intake, thereby causing sodium retention and a rise in blood pressure. The effect is dependent on plasma potassium, which modulates DCT cell membrane voltage and, in turn, intracellular chloride. Low intracellular chloride stimulates WNK kinases to activate NCC, limiting potassium losses, even at the expense of increased blood pressure. These data show that DCT cells, like adrenal cells, sense potassium via membrane voltage. In the DCT, hyperpolarization activates NCC via WNK kinases, whereas in the adrenal gland, it inhibits aldosterone secretion. These effects work in concert to maintain potassium homeostasis. PMID:25565204

ISMP Adverse Drug Reactions: Pregabalin-Induced Stuttering Nitroglycerine-Induced Bradycardia Progressing to Asystole Minocycline-Induced DRESS Leading to Liver Transplantation and Type 1 Diabetes Increased Risk of Vertebral Fractures in Women Receiving Thiazide or Loop Diuretics Gambling Disorder and Impulse Control Disorder with Aripiprazole.

PubMed

Mancano, Michael A

2017-04-01

The purpose of this feature is to heighten awareness of specific adverse drug reactions (ADRs), discuss methods of prevention, and promote reporting of ADRs to the US Food and Drug Administration's (FDA's) MedWatch program (800-FDA-1088). If you have reported an interesting, preventable ADR to MedWatch, please consider sharing the account with our readers. Write to Dr. Mancano at ISMP, 200 Lakeside Drive, Suite 200, Horsham, PA 19044 (phone: 215-707-4936; e-mail: mmancano@temple.edu). Your report will be published anonymously unless otherwise requested. This feature is provided by the Institute for Safe Medication Practices (ISMP) in cooperation with the FDA's MedWatch program and Temple University School of Pharmacy. ISMP is an FDA MedWatch partner.

Cost–Utility of Angiotensin-Converting Enzyme Inhibitor-Based Treatment Compared With Thiazide Diuretic-Based Treatment for Hypertension in Elderly Australians Considering Diabetes as Comorbidity

PubMed Central

Chowdhury, Enayet K.; Ademi, Zanfina; Moss, John R.; Wing, Lindon M.H.; Reid, Christopher M.

2015-01-01

Abstract The objective of this study was to examine the cost-effectiveness of angiotensin-converting enzyme inhibitor (ACEI)-based treatment compared with thiazide diuretic-based treatment for hypertension in elderly Australians considering diabetes as an outcome along with cardiovascular outcomes from the Australian government's perspective. We used a cost–utility analysis to estimate the incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year (QALY) gained. Data on cardiovascular events and new onset of diabetes were used from the Second Australian National Blood Pressure Study, a randomized clinical trial comparing diuretic-based (hydrochlorothiazide) versus ACEI-based (enalapril) treatment in 6083 elderly (age ≥65 years) hypertensive patients over a median 4.1-year period. For this economic analysis, the total study population was stratified into 2 groups. Group A was restricted to participants diabetes free at baseline (n = 5642); group B was restricted to participants with preexisting diabetes mellitus (type 1 or type 2) at baseline (n = 441). Data on utility scores for different events were used from available published literatures; whereas, treatment and adverse event management costs were calculated from direct health care costs available from Australian government reimbursement data. Costs and QALYs were discounted at 5% per annum. One-way and probabilistic sensitivity analyses were performed to assess the uncertainty around utilities and cost data. After a treatment period of 5 years, for group A, the ICER was Australian dollars (AUD) 27,698 (€ 18,004; AUD 1–€ 0.65) per QALY gained comparing ACEI-based treatment with diuretic-based treatment (sensitive to the utility value for new-onset diabetes). In group B, ACEI-based treatment was a dominant strategy (both more effective and cost-saving). On probabilistic sensitivity analysis, the ICERs per QALY gained were always below AUD 50,000 for group B; whereas for group A, the probability of being below AUD 50,000 was 85%. Although the dispensed price of diuretic-based treatment of hypertension in the elderly is lower, upon considering the potential enhanced likelihood of the development of diabetes in addition to the costs of treating cardiovascular disease, ACEI-based treatment may be a more cost-effective strategy in this population. PMID:25738481

Capacity of Health Facilities to Manage Hypertension in Mukono and Buikwe Districts in Uganda: Challenges and Recommendations

PubMed Central

Musinguzi, Geofrey; Bastiaens, Hilde; Wanyenze, Rhoda K.; Mukose, Aggrey; Van geertruyden, Jean-Pierre; Nuwaha, Fred

2015-01-01

Background The burden of chronic diseases is increasing in both low- and middle-income countries. However, healthcare systems in low-income countries are inadequately equipped to deal with the growing disease burden, which requires chronic care for patients. The aim of this study was to assess the capacity of health facilities to manage hypertension in two districts in Uganda. Methods In a cross-sectional study conducted between June and October 2012, we surveyed 126 health facilities (6 hospitals, 4 Health Center IV (HCIV), 23 Health Center III (HCIII), 41 Health Center II (HCII) and 52 private clinics/dispensaries) in Mukono and Buikwe districts in Uganda. We assessed records, conducted structured interviews with heads of facilities, and administered questionnaires to 271 health workers. The study assessed service provision for hypertension, availability of supplies such as medicines, guidelines and equipment, in-service training for hypertension, knowledge of hypertension management, challenges and recommendations. Results Of the 126 health facilities, 92.9% reported managing (diagnosing/treating) patients with hypertension, and most (80.2%) were run by non-medical doctors or non-physician health workers (NPHW). Less than half (46%) of the facilities had guidelines for managing hypertension. A 10th of the facilities lacked functioning blood pressure devices and 28% did not have stethoscopes. No facilities ever calibrated their BP devices except one. About a half of the facilities had anti-hypertensive medicines in stock; mainly thiazide diuretics (46%), beta blockers (56%) and calcium channel blockers (48.4%). Alpha blockers, mixed alpha & beta blockers and angiotensin II receptor antagonists were only stocked by private clinics/dispensaries. Most HCIIs lacked anti-hypertensive medicines, including the first line thiazide diuretics. Significant knowledge gaps in classification of patients as hypertensive were noted among respondents. All health workers (except 5, 1.9%) indicated that they needed additional training in hypertension management. Several provider and patient related challenges were also observed in this study. Conclusions Health facilities in this setting are inadequately equipped to provide services for management of hypertension. Diagnostic equipment, anti-hypertensive drugs and personnel present great challenges. To address the increasing burden of hypertension and other chronic diseases, measures are needed to substantially strengthen the healthcare facilities, including training of personnel in management of hypertension and other chronic diseases, and improving diagnostic and treatment supplies. PMID:26560131

Capacity of Health Facilities to Manage Hypertension in Mukono and Buikwe Districts in Uganda: Challenges and Recommendations.

PubMed

Musinguzi, Geofrey; Bastiaens, Hilde; Wanyenze, Rhoda K; Mukose, Aggrey; Van Geertruyden, Jean-Pierre; Nuwaha, Fred

2015-01-01

The burden of chronic diseases is increasing in both low- and middle-income countries. However, healthcare systems in low-income countries are inadequately equipped to deal with the growing disease burden, which requires chronic care for patients. The aim of this study was to assess the capacity of health facilities to manage hypertension in two districts in Uganda. In a cross-sectional study conducted between June and October 2012, we surveyed 126 health facilities (6 hospitals, 4 Health Center IV (HCIV), 23 Health Center III (HCIII), 41 Health Center II (HCII) and 52 private clinics/dispensaries) in Mukono and Buikwe districts in Uganda. We assessed records, conducted structured interviews with heads of facilities, and administered questionnaires to 271 health workers. The study assessed service provision for hypertension, availability of supplies such as medicines, guidelines and equipment, in-service training for hypertension, knowledge of hypertension management, challenges and recommendations. Of the 126 health facilities, 92.9% reported managing (diagnosing/treating) patients with hypertension, and most (80.2%) were run by non-medical doctors or non-physician health workers (NPHW). Less than half (46%) of the facilities had guidelines for managing hypertension. A 10th of the facilities lacked functioning blood pressure devices and 28% did not have stethoscopes. No facilities ever calibrated their BP devices except one. About a half of the facilities had anti-hypertensive medicines in stock; mainly thiazide diuretics (46%), beta blockers (56%) and calcium channel blockers (48.4%). Alpha blockers, mixed alpha & beta blockers and angiotensin II receptor antagonists were only stocked by private clinics/dispensaries. Most HCIIs lacked anti-hypertensive medicines, including the first line thiazide diuretics. Significant knowledge gaps in classification of patients as hypertensive were noted among respondents. All health workers (except 5, 1.9%) indicated that they needed additional training in hypertension management. Several provider and patient related challenges were also observed in this study. Health facilities in this setting are inadequately equipped to provide services for management of hypertension. Diagnostic equipment, anti-hypertensive drugs and personnel present great challenges. To address the increasing burden of hypertension and other chronic diseases, measures are needed to substantially strengthen the healthcare facilities, including training of personnel in management of hypertension and other chronic diseases, and improving diagnostic and treatment supplies.

Diabetes insipidus in infants and children.

PubMed

Dabrowski, Elizabeth; Kadakia, Rachel; Zimmerman, Donald

2016-03-01

Diabetes insipidus, the inability to concentrate urine resulting in polyuria and polydipsia, can have different manifestations and management considerations in infants and children compared to adults. Central diabetes insipidus, secondary to lack of vasopressin production, is more common in children than is nephrogenic diabetes insipidus, the inability to respond appropriately to vasopressin. The goal of treatment in both forms of diabetes insipidus is to decrease urine output and thirst while allowing for appropriate fluid balance, normonatremia and ensuring an acceptable quality of life for each patient. An infant's obligate need to consume calories as liquid and the need for readjustment of medication dosing in growing children both present unique challenges for diabetes insipidus management in the pediatric population. Treatment modalities typically include vasopressin or thiazide diuretics. Special consideration must be given when managing diabetes insipidus in the adipsic patient, post-surgical patient, and in those undergoing chemotherapy or receiving medications that alter free water clearance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aldosterone Modulates the Association between NCC and ENaC.

PubMed

Wynne, Brandi M; Mistry, Abinash C; Al-Khalili, Otor; Mallick, Rickta; Theilig, Franziska; Eaton, Douglas C; Hoover, Robert S

2017-06-23

Distal sodium transport is a final step in the regulation of blood pressure. As such, understanding how the two main sodium transport proteins, the thiazide-sensitive sodium chloride cotransporter (NCC) and the epithelial sodium channel (ENaC), are regulated is paramount. Both are expressed in the late distal nephron; however, no evidence has suggested that these two sodium transport proteins interact. Recently, we established that these two sodium transport proteins functionally interact in the second part of the distal nephron (DCT2). Given their co-localization within the DCT2, we hypothesized that NCC and ENaC interactions might be modulated by aldosterone (Aldo). Aldo treatment increased NCC and αENaC colocalization (electron microscopy) and interaction (coimmunoprecipitation). Finally, with co-expression of the Aldo-induced protein serum- and glucocorticoid-inducible kinase 1 (SGK1), NCC and αENaC interactions were increased. These data demonstrate that Aldo promotes increased interaction of NCC and ENaC, within the DCT2 revealing a novel method of regulation for distal sodium reabsorption.

Potassium modulates electrolyte balance and blood pressure through effects on distal cell voltage and chloride.

PubMed

Terker, Andrew S; Zhang, Chong; McCormick, James A; Lazelle, Rebecca A; Zhang, Chengbiao; Meermeier, Nicholas P; Siler, Dominic A; Park, Hae J; Fu, Yi; Cohen, David M; Weinstein, Alan M; Wang, Wen-Hui; Yang, Chao-Ling; Ellison, David H

2015-01-06

Dietary potassium deficiency, common in modern diets, raises blood pressure and enhances salt sensitivity. Potassium homeostasis requires a molecular switch in the distal convoluted tubule (DCT), which fails in familial hyperkalemic hypertension (pseudohypoaldosteronism type 2), activating the thiazide-sensitive NaCl cotransporter, NCC. Here, we show that dietary potassium deficiency activates NCC, even in the setting of high salt intake, thereby causing sodium retention and a rise in blood pressure. The effect is dependent on plasma potassium, which modulates DCT cell membrane voltage and, in turn, intracellular chloride. Low intracellular chloride stimulates WNK kinases to activate NCC, limiting potassium losses, even at the expense of increased blood pressure. These data show that DCT cells, like adrenal cells, sense potassium via membrane voltage. In the DCT, hyperpolarization activates NCC via WNK kinases, whereas in the adrenal gland, it inhibits aldosterone secretion. These effects work in concert to maintain potassium homeostasis. Copyright © 2015 Elsevier Inc. All rights reserved.

Expression of the sodium potassium chloride cotransporter (NKCC1) and sodium chloride cotransporter (NCC) and their effects on rat lens transparency.

PubMed

Chee, K N; Vorontsova, I; Lim, J C; Kistler, J; Donaldson, P J

2010-05-04

To characterize the expression patterns of the Na+-K+-Cl(-) cotransporter (NKCC) 1 and NKCC2, and the Na+-Cl(-) cotransporter (NCC) in the rat lens and to determine if they play a role in regulating lens volume and transparency. RT-PCR was performed on RNA extracted from fiber cells to identify sodium dependent cotransporters expressed in the rat lens. Western blotting and immunohistochemistry, using NKCC1, NKCC2, and NCC antibodies, were used to verify expression at the protein level and to localize transporter expression. Organ cultured rat lenses were incubated in Artificial Aqueous Humor (AAH) of varying osmolarities or isotonic AAH that contained either the NKCC specific inhibitor bumetanide, or the NCC specific inhibitor thiazide for up to 18 h. Lens transparency was monitored with dark field microscopy, while tissue morphology and antibody labeling patterns were recorded using a confocal microscope. Molecular experiments showed that NKCC1 and NCC were expressed in the lens at both the transcript and protein levels, but NKCC2 was not. Immunohistochemistry showed that both NKCC1 and NCC were expressed in the lens cortex, but NCC expression was also found in the lens core. In the lens cortex the majority of labeling for both transporters was cytoplasmic in nature, while in the lens core, NCC labeling was associated with the membrane. Exposure of lenses to either hypotonic or hypertonic AAH had no noticeable effects on the predominantly cytoplasmic location of either transporter in the lens cortex. Incubation of lenses in isotonic AAH plus the NKCC inhibitor bumetanide for 18 h induced a cortical opacity that was initiated by a shrinkage of peripheral fiber cells and the dilation of the extracellular space between fiber cells in a deeper zone located some approximately 150 microm in from the capsule. In contrast, lenses incubated in isotonic AAH and the NCC inhibitor thiazide maintained both their transparency and their regular fiber cell morphology. We have confirmed the expression of NKCC1 in the rat lens and report for the first time the expression of NCC in lens fiber cells. The expression patterns of the two transporters and the differential effects of their specific inhibitors on fiber cell morphology indicate that these transporters play distinct roles in the lens. NKCC1 appears to mediate ion influx in the lens cortex while NCC may play a role in the lens nucleus.

Resistant Hypertension On Treatment (ResHypOT): sequential nephron blockade compared to dual blockade of the renin-angiotensin-aldosterone system plus bisoprolol in the treatment of resistant arterial hypertension - study protocol for a randomized controlled trial.

PubMed

Cestário, Elizabeth do Espirito Santo; Fernandes, Letícia Aparecida Barufi; Giollo-Júnior, Luiz Tadeu; Uyemura, Jéssica Rodrigues Roma; Matarucco, Camila Suemi Sato; Landim, Manoel Idelfonso Paz; Cosenso-Martin, Luciana Neves; Tácito, Lúcia Helena Bonalume; Moreno, Heitor; Vilela-Martin, José Fernando; Yugar-Toledo, Juan Carlos

2018-02-12

Resistant hypertension is characterized when the blood pressure (BP) remains above the recommended goal after taking three antihypertensive drugs with synergistic actions at their maximum recommended tolerated doses, preferably including a diuretic. Identifying the contribution of intravascular volume and serum renin in maintaining BP levels could help tailor more effective hypertension treatment, whether acting on the control of intravascular volume or sodium balance, or acting on the effects of the renin-angiotensin-aldosterone system (RAAS) on the kidney. This is a randomized, open-label, clinical trial is designed to compare sequential nephron blockade and its contribution to the intravascular volume component with dual blockade of the RAAS plus bisoprolol and the importance of serum renin in maintaining BP levels. The trial has two arms: sequential nephron blockade versus dual blockade of the RAAS (with an angiotensin converting enzyme (ACE) inhibitor plus a beta-blocker) both added-on to a thiazide diuretic, a calcium-channel blocker and an angiotensin receptor-1 blocker (ARB). Sequential nephron blockade consists in a progressive increase in sodium depletion using a thiazide diuretic, an aldosterone-receptor blocker, furosemide and, finally, amiloride. On the other hand, the dual blockade of the RAAS consists of the progressive addition of an ACE inhibitor until the maximum dose and then the administration of a beta-blocker until the maximum dose. The primary outcomes will be reductions in the systolic BP, diastolic BP, mean BP and pulse pressure (PP) after 20 weeks of treatment. The secondary outcomes will evaluate treatment safety and tolerability, biochemical changes, evaluation of renal function and recognition of hypotension (ambulatory BP monitoring (ABPM)). The sample size was calculated assuming an alpha error of 5% to reject the null hypothesis with a statistical power of 80% giving a total of 40 individuals per group. In recent years, the cost of resistant hypertension (RH) treatment has increased. Thus, identifying the contribution of intravascular volume and serum renin in maintaining BP levels could help tailor more effective hypertension treatment, whether by acting on the control of intravascular volume or sodium balance, or by acting on the effects of the RAAS on the kidney. Sequential Nephron Blockade vs. Dual Blockade Renin-angiotensin System + Bisoprolol in Resistant Arterial Hypertension (ResHypOT). ClinicalTrials.gov, ID: NCT02832973 . Registered on 14 July 2016. First received: 12 June 2016. Last updated: 18 July 2016.

The target-specific transporter and current status of diuretics as antihypertensive.

PubMed

Ali, Syed Salman; Sharma, Pramod Kumar; Garg, Vipin Kumar; Singh, Avnesh Kumar; Mondal, Sambhu Charan

2012-04-01

The currently available diuretics increase the urinary excretion of sodium chloride by selective inhibition of specific sodium transporters in the loop of Henle and distal nephron. In recent years, the molecular cloning of the diuretic-sensitive sodium transporters at distal convoluted tubule has improved our understanding of the cellular mechanisms of action of each class of diuretics. Diuretics are tools of considerable therapeutic importance. First, they effectively reduce blood pressure. Loop and thiazide diuretics are secreted from the proximal tubule via the organic anion transporter-1 and exert their diuretic action by binding to the Na(+)-K(+)-2Cl(-) co-transporter type 2 in the thick ascending limb and the Na(+)-Cl(-) co-transporter in the distal convoluted tubule, respectively. Recent studies in animal models suggest that abundance of these ion transporters is affected by long-term diuretic administration. The WHO/ISH guidelines point out that diuretics enhance the efficacy of antihypertensive drugs and will most often be a component of combination therapy. © 2011 The Authors Fundamental and Clinical Pharmacology © 2011 Société Française de Pharmacologie et de Thérapeutique.

[Diuretics in monotherapy and in combination with other diuretics and nondiuretics in the treatment of hypertension].

PubMed

Spinar, J; Spinarová, L; Vítovec, J

2013-06-01

Diuretics belong to the basic group of medicines for the treatment of hypertension and heart failure. In the case of hypertension treatment, their main indication is higher age and isolated systolic hypertension. In the case of heart failure they are used for the treatment of swellings and shortness of breath. The most frequently prescribed group of diuretics is thiazides and similar products. In patients with renal insufficiency, loop diuretics are administered. In the case of hypertension, diuretics are mainly used in the combination treatment. The most frequently used diuretic in combination is again hydrochlorothiazide, which is combined with reninangiotensin system blockers. It is mainly the combination of an ACE inhibitor + indapamide that seems to be modern and promising, and it is, on the basis of large clinical trials, recommended also for diabetics (ADVANCE) or for secondary prevention following a cerebrovascular accident (PROGRESS) or for the elderly (HYVET). Also a combination of two diuretics is popular -  mainly hydrochlorothiazide + amiloride. A combination of a betablocker and diuretic is less suitable.

Congenital chloride diarrhea misdiagnosed as pseudo-Bartter syndrome.

PubMed

Saneian, Hossein; Bahraminia, Emad

2013-09-01

Congenital chloride diarrhea (CCD) is a rare autosomal recessive disease which is characterized by intractable diarrhea of infancy, failure to thrive, high fecal chloride, hypochloremia, hypokalemia, hyponatremia and metabolic alkalosis. In this case report, we present the first female and the second official case of CCD in Iran. A 15-month-old girl referred to our hospital due to failure to thrive and poor feeding. She had normal kidneys, liver and spleen. Treating her with Shohl's solution, thiazide and zinc sulfate did not result in weight gain. Consequently, pseudo-Bartter syndrome was suspected, she was treated with intravenous (IV) therapy to which she responded dramatically. In addition, hypokalemia resolved quickly. Since this does not usually happen in patients with the pseudo-Bartter syndrome, stool tests were performed. Abnormal level of chloride in stool suggested CCD and she was thus treated with IV fluid replacement, Total parentral nutrition and high dose of oral omeprazole (3 mg/kg/day). She gained 1 kg of weight and is doing fine until present. CCD is a rare hereditary cause of intractable diarrhea of infancy. It should be considered in infants with unknown severe electrolyte disturbances.

Gitelman or Bartter type 3 syndrome? A case of distal convoluted tubulopathy caused by CLCNKB gene mutation

PubMed Central

Cruz, António José; Castro, Alexandra

2013-01-01

A 32-year-old woman with no significant medical history was sent to our consultation due to hypokalaemia (<3.0 mmol/l). Her main complaints were longstanding polyuria and nocturia. Physical examination was normal. Basic investigations showed normal renal function, low serum potassium (2.7 mmol/l) and magnesium (0.79 mmol/l), metabolic alkalosis (pH 7.54; bicarbonate 32.5 mmol/l), elevated urinary potassium (185 mmol/24 h) and normal urinary calcium (246 mg/24 h). Thiazide test revealed blunted response. Chronic vomiting and the abuse of diuretics were excluded. Genetic tests for SLC12A3 gene mutation described in Gitelman syndrome (GS) came negative. CLCNKB gene mutation analysis present in both GS and Bartter (BS) type 3 syndromes was positive. The patient is now being treated with potassium and magnesium oral supplements, ramipril and spironolactone with stable near-normal potassium and magnesium levels. This article presents the case of a patient with hypokalaemia caused by CLCNKB gene mutation hard to categorise as GS or BS type 3. PMID:23345488

Gitelman or Bartter type 3 syndrome? A case of distal convoluted tubulopathy caused by CLCNKB gene mutation.

PubMed

Cruz, António José; Castro, Alexandra

2013-01-22

A 32-year-old woman with no significant medical history was sent to our consultation due to hypokalaemia (<3.0 mmol/l). Her main complaints were longstanding polyuria and nocturia. Physical examination was normal. Basic investigations showed normal renal function, low serum potassium (2.7 mmol/l) and magnesium (0.79 mmol/l), metabolic alkalosis (pH 7.54; bicarbonate 32.5 mmol/l), elevated urinary potassium (185 mmol/24 h) and normal urinary calcium (246 mg/24 h). Thiazide test revealed blunted response. Chronic vomiting and the abuse of diuretics were excluded. Genetic tests for SLC12A3 gene mutation described in Gitelman syndrome (GS) came negative. CLCNKB gene mutation analysis present in both GS and Bartter (BS) type 3 syndromes was positive. The patient is now being treated with potassium and magnesium oral supplements, ramipril and spironolactone with stable near-normal potassium and magnesium levels. This article presents the case of a patient with hypokalaemia caused by CLCNKB gene mutation hard to categorise as GS or BS type 3.

Management of diabetic hypertensives

PubMed Central

Ganesh, Jai; Viswanathan, Vijay

2011-01-01

Hypertension occurs twice as commonly in diabetics than in comparable nondiabetics. Patients with both disorders have a markedly higher risk for premature microvascular and macrovascular complications. Aggressive control of blood pressure (BP) reduces both micro- and macrovascular complications. In diabetic hypertensives, angiotensin converting enzyme inhibitors (ACEIs) are the first line in management of hypertension, and can be replaced by angiotensin II receptor blockers (ARBs) if patients are intolerant of them. Recent studies suggest ARBs to be on par with ACEI in reducing both macro- and microvascular risks. Adding both these agents may have a beneficial effect on proteinuria, but no extra macrovascular risk reduction. Thiazides can also be used as first line drugs, but are better used along with ACEI/ARBs. Beta-blockers [especially if the patient has coronary artery disease] and calcium channel blockers are used as second line add-on drugs. Multidrug regimens are commonly needed in diabetic hypertensives. Achieving the target BP of <130/80 is the priority rather than the drug combination used in order to arrest and prevent the progression of macro- and microvascular complications in diabetic hypertensives. PMID:22145142

Drug treatment of hypertension in older patients with diabetes mellitus.

PubMed

Yandrapalli, Srikanth; Pal, Suman; Nabors, Christopher; Aronow, Wilbert S

2018-05-01

Hypertension is more prevalent in the elderly (age>65 years) diabetic population than in the general population and shows an increasing prevalence with advancing age. Both diabetes mellitus (DM) and hypertension are independent risk factors for cardiovascular (CV) related morbidity and mortality. Optimal BP targets were not identified in elderly patients with DM and hypertension. Areas covered: In this review article, the authors briefly discuss the pathophysiology of hypertension in elderly diabetics, present evidence with various antihypertensive drug classes supporting the treatment of hypertension to reduce CV events in older diabetics, and then discuss the optimal target BP goals in these patients. Expert opinion: Clinicians should have a BP goal of less than 130/80 mm in all elderly patients with hypertension and DM, especially in those with high CV-risk. When medications are required for optimal BP control in addition to lifestyle measures, either thiazide diuretics, angiotensin-converting-enzyme inhibitors, angiotensin receptor blockers, or calcium channel blockers should be considered as initial therapy. Combinations of medications are usually required in these patients because BP control is more difficult to achieve in diabetics than those without DM.

Hyperkalemia in young children: blood pressure checked?

PubMed

Hollander, Richard; Mortier, Geert; van Hoeck, Koen

2016-12-01

Hyperkalemia in young children is a rare phenomenon and in many cases caused by hemolysis in the specimen due to difficulties in obtaining a sample. However, hyperkalemia can also be a sign of a rare Mendelian syndrome known as familial hyperkalemic hypertension or pseudohypoaldosteronism type II. This disease is characterized by hyperkalemia, hypertension, and mild hyperchloremic metabolic acidosis (with normal anion gap) despite normal glomerular filtration. Full recovery of these abnormalities with thiazide diuretics is essential not to miss the diagnosis of this syndrome. We describe two young patients with hyperkalemia as an incidental finding who were subsequently diagnosed with this rare endocrine disorder. Genetic testing revealed mutations in two recently discovered genes, the study of which has helped to unravel the pathophysiologic pathways. In patients with hyperkalemia and a normal glomerular filtration rate, the clinician should actively search for abnormalities in blood pressure since recognizing this condition can lead to simple, cheap, and effective treatment. What is Known: • True Hyperkalemia is rare in pediatrics and can be a sign of FHHt. What is New: • KLHL3 & CUL3 are recently discovered genes helping unravel the pathophysiologic pathway of FHHt.

Diabetes insipidus: The other diabetes

PubMed Central

Kalra, Sanjay; Zargar, Abdul Hamid; Jain, Sunil M.; Sethi, Bipin; Chowdhury, Subhankar; Singh, Awadhesh Kumar; Thomas, Nihal; Unnikrishnan, A. G.; Thakkar, Piya Ballani; Malve, Harshad

2016-01-01

Diabetes insipidus (DI) is a hereditary or acquired condition which disrupts normal life of persons with the condition; disruption is due to increased thirst and passing of large volumes of urine, even at night. A systematic search of literature for DI was carried out using the PubMed database for the purpose of this review. Central DI due to impaired secretion of arginine vasopressin (AVP) could result from traumatic brain injury, surgery, or tumors whereas nephrogenic DI due to failure of the kidney to respond to AVP is usually inherited. The earliest treatment was posterior pituitary extracts containing vasopressin and oxytocin. The synthetic analog of vasopressin, desmopressin has several benefits over vasopressin. Desmopressin was initially available as intranasal preparation, but now the oral tablet and melt formulations have gained significance, with benefits such as ease of administration and stability at room temperature. Other molecules used for treatment include chlorpropamide, carbamazepine, thiazide diuretics, indapamide, clofibrate, indomethacin, and amiloride. However, desmopressin remains the most widely used drug for the treatment of DI. This review covers the physiology of water balance, causes of DI and various treatment modalities available, with a special focus on desmopressin. PMID:26904464

[Hypercalciuria].

PubMed

Périmenis, P; Wémeau, J-L; Vantyghem, M-C

2005-12-01

The frequency of hypercalciuria is increasing in western countries with an incidence of nephrolithiasis which can reach 13%. Hypercalciuria appears as an alteration of the calcium transport system (kidney, bowel, bone) which is regulated by calcitriol and parathormone. The aim of this review was to screen etiologies of hypercalciuria taking into account recent genetic advances (calcium epithelial channel and calcium sensing receptor). Hypercalciuria may be favored by nutritional causes (diet rich in calcium, sodium, carbohydrates, proteins, poor in phosphates and potassium). It may also be related to an increase in calcium absorption (vitamin D excess, primary hyperparathyroidism, sarcoidosis, lymphoma, estrogens, and certain genetic causes), an increase in osteoresorption (bone metastasis, myeloma, Paget, hyperthyroidism, immobilization, hypercortisolism and corticosteroid therapy), or a decrease of kidney tubular resorption (diuretics, Cacci and Ricci, acromegally, Bartter, familial dominant hypocalcemia, Fanconi, Dent, familial hypomagnesemia-hypercalciuria syndrome, type 1 distal tubular acidosis, pseudohypoaldosteronism, diabetes). If no cause is identified, persistence of hypercalciuria after instituting a correct diet is defined as idiopathic hypercalciuria. Treatment of the cause is essential in secondary hypercalciuria, in addition to diet (low sodium intake, normocalcic diet, hydration), associated with thiazide diuretics and biphosphonates if necessary.

Resistant and Refractory Hypertension: Antihypertensive Treatment Resistance vs Treatment Failure

PubMed Central

Siddiqui, Mohammed; Dudenbostel, Tanja; Calhoun, David A.

2017-01-01

Resistant or difficult to treat hypertension is defined as high blood pressure that remains uncontrolled with 3 or more different antihypertensive medications, including a diuretic. Recent definitions also include controlled blood pressure with use of 4 or more medications as also being resistant to treatment. Recently, refractory hypertension, an extreme phenotype of antihypertensive treatment failure has been defined as hypertension uncontrolled with use of 5 or more antihypertensive agents, including a long-acting thiazide diuretic and a mineralocorticoid receptor antagonist. Patients with resistant vs refractory hypertension share similar characteristics and comorbidities, including obesity, African American race, female sex, diabetes, coronary heart disease, chronic kidney disease, and obstructive sleep apnea. Patients with refractory vs resistant hypertension tend to be younger and are more likely to have been diagnosed with congestive heart failure. Refractory hypertension might also differ from resistant hypertension in terms of underlying cause. Preliminary evidence suggests that refractory hypertension is more likely to be neurogenic in etiology (ie, heightened sympathetic tone), vs a volume-dependent hypertension that is more characteristic of resistant hypertension in general. PMID:26514749

Antihypertensive drug prescription trends at the primary health care centres in Bahrain.

PubMed

Jassim al Khaja, K A; Sequeira, R P; Wahab, A W; Mathur, V S

2001-05-01

To determine the antihypertensive drug prescribing pattern by primary care physicians in patients with uncomplicated essential hypertension; to identify whether such pattern of prescription is appropriate and in accordance with international guidelines for pharmacotherapy of hypertension; and to estimate the impact of such prescriptions on cost of treatment. A prescription-based survey among patients with uncomplicated essential hypertension was conducted in seven out of a total of 18 health centres in Bahrain. The relevant data for our study was collected using cards, designed for chronically-ill patients. A total of 1019 male and 1395 female (62.9%) out of 3838 of the study population were on monotherapy, whereas 596 male and 828 female (37.1%) were on antihypertensive combination therapy. Among the monotherapy category, the various antihypertensive drugs used were as follows: beta-blockers (58.8%), angiotensin converting enzyme (ACE) inhibitors (14.2%), calcium channel blockers (11.1%), diuretics (8.1%) and alpha-methyldopa (7.0%). With respect to overall utilization pattern, beta-blockers were the most frequently prescribed (65.5%), diuretics ranked second (27.4%), followed by ACE inhibitors (20.6%), calcium channel blockers (19.9%) and alpha-methyldopa (8.5%). Within each class of antihypertensives used, the most frequently used individual agents were as follows: (a) among beta-blockers 97.7% used atenolol; (b) among the diuretics, indapamide (35.4%), hydrochlorothiazide (HCTZ) (32.7%), HCTZ in combination with triamterene (25.7%), and chlorthalidone (4.6%); (c) among the ACE inhibitors, captopril (44.9%), enalapril (29.7%), and lisinopril (19.0%); (d) among the calcium channel blockers, nifedipine (98.2%). Significant age- and gender-related differences in prescribing patterns were seen. Short-acting nifedipine monotherapy was inappropriately prescribed in a significant number of patients above the age of 50 years. ACE inhibitors accounted for approximately two-thirds of the total antihypertensive drug expenditure, although these drugs represent only one-fifth of overall antihypertensives used. There is a trend towards excessive use of expensive thiazide-like diuretics such as indapamide which seems to be unjustifiable practice, particularly in a study population free from diabetic hypertensive patients. The general pattern of antihypertensive utilization appears to be in accordance with the guidelines of WHO and the Joint National Committee issued in the 1990s. The trends of prescribing of antihypertensives were in favour of conventional ones such as the beta blockers and diuretics, and the introduction of newer classes of antihypertensives had a generally minimal impact on the prescribing profile. Almost two-thirds of the patients were treated with monotherapy. A disproportionately large percentage of antihypertensive drug cost was due to overt use of ACE inhibitors, and indapamide, instead of thiazide diuretics. The use of short-acting calcium channel blockers especially in the elderly is unjustifiable.

Captopril as a replacement for multiple therapy in hypertension: a controlled study.

PubMed

Yodfat, Y; Fidel, J; Bloom, D S

1985-11-01

A controlled study was conducted in hypertensive patients to investigate whether captopril can be substituted for the various other antihypertensive drugs (not including diuretics) to reduce side effects and improve the quality of life. Captopril in a twice daily dose of 25-50 mg, was substituted and titrated in 54 patients. Fifty-two patients, matched by age and sex, comprised the control group, and were treated with a variety of agents. During a follow-up of 9 months, 44 of the patients receiving captopril (81%) achieved the goal of supine blood pressure less than 90 mmHg. Captopril was discontinued in two patients due to side effects. Mild proteinuria was observed in two patients. A significant reduction in scores or rates of side effects (numbness, blurred vision, insomnia, vivid dreams, cold extremities, sleepiness, sexual dysfunction and fatigue) and improvement in quality of life (general feeling, mood and concentration) was observed in the study group compared with the control group. Captopril alone in a twice daily dose of 25-50 mg, or in co-treatment with thiazide, provided sustained blood pressure control with minimal side effects and improvement in quality of life compared with the treatment of hypertension with beta-blockers, vasodilators or methyldopa.

Epidemiology of Gallbladder Disease: Cholelithiasis and Cancer

PubMed Central

Stinton, Laura M.

2012-01-01

Diseases of the gallbladder are common and costly. The best epidemiological screening method to accurately determine point prevalence of gallstone disease is ultrasonography. Many risk factors for cholesterol gallstone formation are not modifiable such as ethnic background, increasing age, female gender and family history or genetics. Conversely, the modifiable risks for cholesterol gallstones are obesity, rapid weight loss and a sedentary lifestyle. The rising epidemic of obesity and the metabolic syndrome predicts an escalation of cholesterol gallstone frequency. Risk factors for biliary sludge include pregnancy, drugs like ceftiaxone, octreotide and thiazide diuretics, and total parenteral nutrition or fasting. Diseases like cirrhosis, chronic hemolysis and ileal Crohn's disease are risk factors for black pigment stones. Gallstone disease in childhood, once considered rare, has become increasingly recognized with similar risk factors as those in adults, particularly obesity. Gallbladder cancer is uncommon in developed countries. In the U.S., it accounts for only ~ 5,000 cases per year. Elsewhere, high incidence rates occur in North and South American Indians. Other than ethnicity and female gender, additional risk factors for gallbladder cancer include cholelithiasis, advancing age, chronic inflammatory conditions affecting the gallbladder, congenital biliary abnormalities, and diagnostic confusion over gallbladder polyps. PMID:22570746

KIDNEY STONES: AN UPDATE ON CURRENT PHARMACOLOGICAL MANAGEMENT AND FUTURE DIRECTIONS

PubMed Central

Xu, Hongshi; Zisman, Anna L.; Coe, Fredric L.; Worcester, Elaine M.

2013-01-01

Introduction Kidney stones are a common problem worldwide with substantial morbidities and economic costs. Medical therapy reduces stone recurrence significantly. Much progress has been made in the last several decades in improving therapy of stone disease. Areas covered 1) effect of medical expulsive therapy on spontaneous stone passage, 2) pharmacotherapy in the prevention of stone recurrence, 3) future directions in the treatment of kidney stone disease. Expert Opinion fluid intake to promote urine volume of at least 2.5L each day is essential to prevent stone formation. Dietary recommendations should be adjusted based on individual metabolic abnormalities. Properly dosed thiazide treatment is the standard therapy for calcium stone formers with idiopathic hypercalciuria. Potassium alkali therapy is considered for hypocitraturia, but caution should be taken to prevent potential risk of calcium phosphate stone formation. For absorptive hyperoxaluria, low oxalate diet and increased dietary calcium intake are recommended. Pyridoxine has been shown effective in some cases of primary hyperoxaluria type I. Allopurinol is used in calcium oxalate stone formers with hyperuricosuria. Treatment of cystine stones remains challenging. Tiopronin can be used if urinary alkalinization and adequate fluid intake are insufficient. For struvite stones, complete surgical removal coupled with appropriate antibiotic therapy is necessary. PMID:23438422

Idiopathic hypercalciuria and formation of calcium renal stones

PubMed Central

Coe, Fredric L.; Worcester, Elaine M.; Evan, Andrew P.

2018-01-01

The most common presentation of nephrolithiasis is idiopathic calcium stones in patients without systemic disease. Most stones are primarily composed of calcium oxalate and form on a base of interstitial apatite deposits, known as Randall’s plaque. By contrast some stones are composed largely of calcium phosphate, as either hydroxyapatite or brushite (calcium monohydrogen phosphate), and are usually accompanied by deposits of calcium phosphate in the Bellini ducts. These deposits result in local tissue damage and might serve as a site of mineral overgrowth. Stone formation is driven by supersaturation of urine with calcium oxalate and brushite. The level of supersaturation is related to fluid intake as well as to the levels of urinary citrate and calcium. Risk of stone formation is increased when urine citrate excretion is <400 mg per day, and treatment with potassium citrate has been used to prevent stones. Urine calcium levels >200 mg per day also increase stone risk and often result in negative calcium balance. Reduced renal calcium reabsorption has a role in idiopathic hypercalciuria. Low sodium diets and thiazide-type diuretics lower urine calcium levels and potentially reduce the risk of stone recurrence and bone diseas PMID:27452364

Rationale for combination therapy in hypertension management: focus on angiotensin receptor blockers and thiazide diuretics.

PubMed

Nash, David T

2007-04-01

Despite recognition that hypertension is a major risk factor for cardiovascular events and mortality, blood pressure control rates remain low in the US population. Reflecting clinical trial results, hypertension management guidelines assert the clinical benefit of achieving current blood pressure goals and indicate that most patients will require 2 or more drugs to reach goal. Well-designed drug combinations counter hypertension via complementary mechanisms that increase antihypertensive efficacy, potentially with lower rates of adverse events than higher dose monotherapy regimens. Lower adverse event rates, in turn, may contribute to greater adherence with treatment. The combination of a low-dose diuretic with agents that block the effects of the renin-angiotensin system (RAS), such as angiotensin receptor blockers, has been found in numerous clinical trials to be highly effective for lowering blood pressure in patients with uncomplicated as well as high-risk hypertension, with a comparable favorable side effect profile compared with monotherapy. Moreover, agents that block the RAS are associated with a lower risk of new-onset diabetes mellitus than other antihypertensive classes. Complementary combinations of antihypertensive agents provide an efficient and effective approach to hypertension management.

Molecular genetics of G proteins and atherosclerosis risk.

PubMed

Siffert, W

2001-11-01

Using a classical candidate gene approach, we have described a common C825T polymorphism in the gene GNB3 which encodes the ubiquitously expressed beta3 subunit of heterotrimeric G proteins. The 825T allele is associated with alternative splicing of the gene and the formation of a truncated but functionally active beta3 subunit which is referred to as Gbeta3s. Expression of the splice variant results in an enhanced G protein activation on stimulation of G protein-coupled receptors. Carriers of the 825T allele show an increased risk for hypertension and left ventricular hypertrophy. Homo- and heterozygous 825T allele carriers respond with a stronger decrease in blood pressure to therapy with a thiazide diuretic than homozygous 825C allele carriers. Moreover, 825T allele carriers appear to have an increased risk for obesity which appears sensible given the established role of G protein signaling in adipogenesis. The highest frequencies of the 825T allele are found in ethnicities with the highest lifestyle-dependent risk for obesity, e.g., black Africans and East Asians. This suggests that the 825T allele fulfills the criteria of a thrifty genotype.

Therapeutic effects of drug-nutrient interactions in the elderly.

PubMed

Roe, D A

1985-02-01

The elderly are the major drug users both because they need specific prescription drugs for control of chronic diseases and because they make excessive use of over-the-counter (OTC) drugs. Therapeutic drugs that are required may be discontinued because the individuals suffer side effects or because the drug is ineffective. Adverse drug reactions in the elderly may result from drug overuse or misuse, slowed drug metabolism or elimination secondary to aging or to age-related chronic disease, intake of alcohol, food-drug incompatibilities, or nutrient-drug interactions. The timing of drug intake in relation to food intake is an important determinant of therapeutic efficacy in the elderly. Food-drug interactions in the gastrointestinal tract may reduce drug absorption. Enteral formula feeding may also interfere with drug absorption. Conversely, absorption of certain drugs (e.g., thiazides) may be promoted by meal-induced slowing of gastric emptying time. Therapeutic diet prescription can influence drug responses in the elderly because the protein composition of the diet influences the rate of drug metabolism. Nutrient depletion secondary to the effect of drugs may be recognized as an important and often avoidable type of adverse drug reaction.

Revisiting the NaCl cotransporter regulation by with-no-lysine kinases

PubMed Central

Bazúa-Valenti, Silvana

2015-01-01

The renal thiazide-sensitive Na+-Cl− cotransporter (NCC) is the salt transporter in the distal convoluted tubule. Its activity is fundamental for defining blood pressure levels. Decreased NCC activity is associated with salt-remediable arterial hypotension with hypokalemia (Gitelman disease), while increased activity results in salt-sensitive arterial hypertension with hyperkalemia (pseudohypoaldosteronism type II; PHAII). The discovery of four different genes causing PHAII revealed a complex multiprotein system that regulates the activity of NCC. Two genes encode for with-no-lysine (K) kinases WNK1 and WNK4, while two encode for kelch-like 3 (KLHL3) and cullin 3 (CUL3) proteins that form a RING type E3 ubiquitin ligase complex. Extensive research has shown that WNK1 and WNK4 are the targets for the KLHL3-CUL3 complex and that WNKs modulate the activity of NCC by means of intermediary Ste20-type kinases known as SPAK or OSR1. The understanding of the effect of WNKs on NCC is a complex issue, but recent evidence discussed in this review suggests that we could be reaching the end of the dark ages regarding this matter. PMID:25788573

Double knockout of pendrin and Na-Cl cotransporter (NCC) causes severe salt wasting, volume depletion, and renal failure.

PubMed

Soleimani, Manoocher; Barone, Sharon; Xu, Jie; Shull, Gary E; Siddiqui, Faraz; Zahedi, Kamyar; Amlal, Hassane

2012-08-14

The Na-Cl cotransporter (NCC), which is the target of inhibition by thiazides, is located in close proximity to the chloride-absorbing transporter pendrin in the kidney distal nephron. Single deletion of pendrin or NCC does not cause salt wasting or excessive diuresis under basal conditions, raising the possibility that these transporters are predominantly active during salt depletion or in response to excess aldosterone. We hypothesized that pendrin and NCC compensate for loss of function of the other under basal conditions, thereby masking the role that each plays in salt absorption. To test our hypothesis, we generated pendrin/NCC double knockout (KO) mice by crossing pendrin KO mice with NCC KO mice. Pendrin/NCC double KO mice displayed severe salt wasting and sharp increase in urine output under basal conditions. As a result, animals developed profound volume depletion, renal failure, and metabolic alkalosis without hypokalemia, which were all corrected with salt replacement. We propose that the combined inhibition of pendrin and NCC can provide a strong diuretic regimen without causing hypokalemia for patients with fluid overload, including patients with congestive heart failure, nephrotic syndrome, diuretic resistance, or generalized edema.

Identification of fifteen novel mutations in the SLC12A3 gene encoding the Na-Cl Co-transporter in Italian patients with Gitelman syndrome.

PubMed

Syrén, Marie-Louise; Tedeschi, Silvana; Cesareo, Laila; Bellantuono, Rosa; Colussi, Giacomo; Procaccio, Mirella; Alì, Anna; Domenici, Raffaele; Malberti, Fabio; Sprocati, Monica; Sacco, Michele; Miglietti, Nunzia; Edefonti, Alberto; Sereni, Fabio; Casari, Giorgio; Coviello, Domenico A; Bettinelli, Alberto

2002-07-01

The SLC12A3 gene encodes the thiazide-sensitive Na-Cl co-transporter (NCCT) expressed in the apical membrane of the distal convoluted tubule of the kidney. Inactivating mutations of this gene are responsible for Gitelman syndrome (GS), a disorder inherited as an autosomal recessive trait. We searched for SLC12A3 gene mutations in 21 Italian patients with the clinical and biochemical features of GS (hypokalemia, hypomagnesemia, metabolic alkalosis, hypocalciuria, and the absence of nephrocalcinosis). All coding regions with their intron-exon boundaries were analyzed using PCR and SSCP techniques followed by sequencing analysis. We identified 21 different mutations evenly distributed throughout the gene without any mutation hot-spot. Fifteen are novel variants, including 12 missense mutations, one deletion, one deletion-insertion and one splice site mutation: R158Q, T163M, W172R, G316V, G374V, G463E, A464T, S615W, V677M, R852S, R958G, C985Y, 2114-2120delACCAAGT, 2144-2158delGCCTTCTACTCGGATinsTG, and 531-2A>G. Copyright 2002 Wiley-Liss, Inc.

Azilsartan medoxomil in the treatment of hypertension: the definitive angiotensin receptor blocker?

PubMed

Barrios, Vivencio; Escobar, Carlos

2013-11-01

Azilsartan medoxomil is the newest angiotensin receptor blocker marketed for the treatment of arterial hypertension. The aim of this article was to review the available evidence about this drug alone or combined with other antihypertensive agents in the treatment of hypertensive population. For this purpose, a search on MEDLINE and EMBASE databases was performed. The MEDLINE and EMBASE search included both medical subject headings (MeSHs) and keywords including azilsartan or azilsartan medoxomil or angiotensin receptor blockers or renin angiotensin system or chlorthalidone and hypertension. References of the retrieved articles were also screened for additional studies. There were no language restrictions. Azilsartan medoxomil has a potent and persistent ability to inhibit binding of angiotensin II to AT1 receptors, which may play a role in its superior blood pressure (BP) -lowering efficacy compared with other drugs, including ramipril, candesartan, valsartan or olmesartan, without an increase of side effects. Chlortalidone is a diuretic which significantly differs from other classic thiazides and has largely demonstrated clinical benefits in outcome trials. The fixed-dose combination of azilsartan and chlorthalidone has been shown to be more effective than other potent combinations of angiotensin receptor blockers plus hydrochlorothiazide, with a good tolerability profile.

Double knockout of pendrin and Na-Cl cotransporter (NCC) causes severe salt wasting, volume depletion, and renal failure

PubMed Central

Soleimani, Manoocher; Barone, Sharon; Xu, Jie; Shull, Gary E.; Siddiqui, Faraz; Zahedi, Kamyar; Amlal, Hassane

2012-01-01

The Na-Cl cotransporter (NCC), which is the target of inhibition by thiazides, is located in close proximity to the chloride-absorbing transporter pendrin in the kidney distal nephron. Single deletion of pendrin or NCC does not cause salt wasting or excessive diuresis under basal conditions, raising the possibility that these transporters are predominantly active during salt depletion or in response to excess aldosterone. We hypothesized that pendrin and NCC compensate for loss of function of the other under basal conditions, thereby masking the role that each plays in salt absorption. To test our hypothesis, we generated pendrin/NCC double knockout (KO) mice by crossing pendrin KO mice with NCC KO mice. Pendrin/NCC double KO mice displayed severe salt wasting and sharp increase in urine output under basal conditions. As a result, animals developed profound volume depletion, renal failure, and metabolic alkalosis without hypokalemia, which were all corrected with salt replacement. We propose that the combined inhibition of pendrin and NCC can provide a strong diuretic regimen without causing hypokalemia for patients with fluid overload, including patients with congestive heart failure, nephrotic syndrome, diuretic resistance, or generalized edema. PMID:22847418

Clinical Outcomes by Race in Hypertensive Patients with and without the Metabolic Syndrome in ALLHAT

PubMed Central

Wright, Jackson T.; Harris-Haywood, Sonja; Pressel, Sara; Barzilay, Joshua; Baimbridge, Charles; Bareis, Charles J.; Basile, Jan N.; Black, Henry R.; Dart, Richard; Gupta, Alok K.; Hamilton, Bruce P.; Einhorn, Paula T.; Haywood, L. Julian; Jafri, Syed Z.A.; Louis, Gail T.; Whelton, Paul K.; Scott, Cranford L.; Simmons, Debra L.; Stanford, Carol; Davis, Barry R.

2009-01-01

Background Antihypertensive drugs with favorable metabolic effects on glucose and lipid levels are advocated for first-line therapy in hypertensive patients with metabolic/cardiometabolic syndrome (MetS). We compared outcomes by race in black and nonblack hypertensive individuals with and without MetS treated with a thiazide-type diuretic (chlorthalidone), a calcium channel blocker (amlodipine besylate), an α-blocker (doxazosin mesylate), or an angiotensin-converting enzyme inhibitor (lisinopril). Methods A post hoc subgroup analysis from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), a randomized, double-blind, active-controlled hypertension treatment trial in 42 418 participants. We defined MetS as hypertension plus at least 2 of the following: fasting serum glucose level of at least 100 mg/dL, body mass index (calculated as weight in kilograms divided by height in meters squared) of at least 30 kg/m2, fasting triglyceride levels of at least 150 mg/dL, and high-density lipoprotein cholesterol levels of less than 40 mg/dL in men (or less than 50 mg/dL in women). Results Significantly higher rates of heart failure were consistent across all treatment comparisons in those with MetS. Relative risks (RRs) were 1.50 (95% confidence interval [CI], 1.18–1.90), 1.49 (95% CI, 1.17–1.90), and 1.88 (95% CI, 1.42–2.47) in black participants and 1.25 (95% CI, 1.06–1.47), 1.20 (95% CI, 1.01–1.41), and 1.82 (95% CI, 1.51–2.19) in nonblack participants for amlodipine, lisinopril, and doxazosin comparisons with chlorthalidone, respectively. Higher rates for combined cardiovascular disease were observed with lisinopril-chlorthalidone (RR, 1.24 [95% CI, 1.09–1.40] and 1.10 [95% CI, 1.02–1.19], respectively) and doxazosin-chlorthalidone comparisons (RR, 1.37 [95% CI, 1.19–1.58] and 1.18 [95% CI, 1.08– 1.30], respectively), in black and nonblack participants with MetS. Higher rates of stroke were seen in black participants only (RR, 1.37 [95% CI, 1.07–1.76] for the lisinopril-chlorthalidone comparison; RR, 1.49 [95% CI, 1.09–2.03] for the doxazosin-chlorthalidone comparison). Black patients with MetS also had higher rates of end-stage renal disease (RR, 1.70 1 [95% CI, 1.13– 2.55]) with lisinopril compared with chlorthalidone. Conclusions The ALLHAT findings fail to do not support the preference of for calcium channel blockers, α-blockers, or angiotensin-converting enzyme inhibitors compared with thiazide-type diuretics in patients with the MetS, despite their more favorable metabolic profiles. This was particularly true for black participants. PMID:18227370

Current prescription status of antihypertensive drugs with special reference to the use of diuretics in Japan.

PubMed

Ibaraki, Ai; Goto, Wataru; Iura, Rie; Tominaga, Mitsuhiro; Tsuchihashi, Takuya

2017-02-01

The guidelines for the management of hypertension recommend the inclusion of diuretics, especially when three or more antihypertensive drugs are used. The present study investigated the current prescription status of antihypertensive drugs with a particular focus on the use of diuretics in a local district in Japan. Prescriptions, including antihypertensive drugs, were collected from a dispensing pharmacy of the Yahata Pharmacist Association, located in Kitakyushu City, in October 2014. Of the 10 585 prescriptions, calcium channel blockers (CCBs) were prescribed in 73.5%, followed by angiotensin II receptor blockers (ARB, 62.7%), diuretics (16.5%) and β-blockers (13.6%). The average number of drugs used was 1.80. The rates of prescription of diuretics for patients with one, two, three and four drugs were 0.6%, 13.1%, 55.2% and 82.6%, respectively. Diuretics were more frequently prescribed in elderly patients, and the prescription rate of doctors in hospitals was significantly higher than that of general practitioners (19.1% vs. 15.7%, P<0.01). In addition, 40% of patients with thiazide diuretics were prescribed combination tablets of hydrochlorothiazide with ARB, whereas trichlormethiazide (34.9%) and indapamide (19.8%) were used in other patients. Based on these findings, the use of diuretics remains limited, even among patients taking multiple antihypertensive drugs.

Effect of combined treatment with diuretics and gabapentin on convulsive threshold in mice.

PubMed

Łukawski, Krzysztof; Swiderska, Grajyna; Czuczwar, Stanisław J

2013-01-01

Research data show that diuretics can have anticonvulsant properties. This study examined effects of ethacrynic acid, a loop diuretic, and hydrochlorothiazide, a thiazide-type diuretic, on the anticonvulsant activity of gabapentin, a newer antiepileptic drug, in the maximal electroshock seizure threshold test in mice. Diuretics were administered intraperitoneally (ip.) both acutely (single dose) and chronically (once daily for seven days). Electroconvulsions were produced by an alternating current (50 Hz, 500 V, 0.2 s stimulus duration) delivered via ear-clip electrodes by a generator. Additionally, the influence of combined treatment with the diuretics and gabapentin on motor performance in the chimney test has been assessed. In the current study, ethacrynic acid at the chronic dose of 12.5 mg/kg and the single dose of 100 mg/kg did not affect the anticonvulsant activity of gabapentin. Similarly, hydrochlorothiazide (100 mg/kg), both in acute and chronic experiments, had no effect on the gabapentin action. On the other hand, in the chimney test, the combined treatment with ethacrynic acid (100 mg/kg) and gabapentin (50 mg/kg) significantly impaired motor performance in mice. Based on the current preclinical findings, it can be suggested that the diuretics should not affect the anticonvulsant action of gabapentin in epileptic patients. However, the combination of ethacrynic acid with gabapentin may cause neurotoxicity.

Urea transporter proteins as targets for small-molecule diuretics.

PubMed

Esteva-Font, Cristina; Anderson, Marc O; Verkman, Alan S

2015-02-01

Conventional diuretics such as furosemide and thiazides target salt transporters in kidney tubules, but urea transporters (UTs) have emerged as alternative targets. UTs are a family of transmembrane channels expressed in a variety of mammalian tissues, in particular the kidney. UT knockout mice and humans with UT mutations exhibit reduced maximal urinary osmolality, demonstrating that UTs are necessary for the concentration of urine. Small-molecule screening has identified potent and selective inhibitors of UT-A, the UT protein expressed in renal tubule epithelial cells, and UT-B, the UT protein expressed in vasa recta endothelial cells. Data from UT knockout mice and from rodents administered UT inhibitors support the diuretic action of UT inhibition. The kidney-specific expression of UT-A1, together with high selectivity of the small-molecule inhibitors, means that off-target effects of such small-molecule drugs should be minimal. This Review summarizes the structure, expression and function of UTs, and looks at the evidence supporting the validity of UTs as targets for the development of salt-sparing diuretics with a unique mechanism of action. UT-targeted inhibitors may be useful alone or in combination with conventional diuretics for therapy of various oedemas and hyponatraemias, potentially including those refractory to treatment with current diuretics.

Pharmacotherapy-Based Problems in the Management of Diabetes Mellitus: Needs Much More to be Done!

PubMed

Ali, N; Shah, Swa; Khan, J; Rehman, S; Imran, M; Hussian, I; Shehbaz, N; Jamshed, H; Khan, S

2010-07-01

A total of 856 diabetic patients were evaluated for pharmacotherapy-based problems like for possible drug interactions, adverse drug reactions, and other mismatches, if any. Poor correlation between the advised insulin therapy and patients' fasting blood glucose levels (12%, n=103) was observed. To most of the patients (41.66%, n= 357), insulin therapy was advised in combination with glucocorticoides, thiazides diuretics, and propranolol. Prescribing beta blocker (propranolol) with insulin is contraindicated. The higher incidence of diabetic foot patients was in the mean age of 57±3.4 years that was controlled with combination therapy of insulin and oral antidiabetics (63.0%, n=516). 11.1% of the treated patients could not take the prescribed therapy due to poor acceptance of insulin therapy due to its syringe needle prick. 41.66% risks of potential drug interactions, 7.93% adverse drug reactions, and 6.6% mismatches were recorded, as per the international approved algorithm, for managing a diabetes mellitus that reflects poor health care system. All these events necessitate for coordinating with other health professionals to make the therapy safer in the better interest of the patients. It is concluded that in practice prescribing pattern carries more risks for patients. It is imperative to improve the practice of pharmacotherapeutics rather than to practice in routine.

Spine mineral change during osteoporosis therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Powell, M.R.; Kolb, F.O.; Meier, K.A.

1985-05-01

Osteoporosis therapy has been handicapped by lack of means to quantitate the process. Dual photon absorptiometry (DPA) offers accurate (4%) and precise (2%) estimation of lumbar spine mineral. The authors followed 42 osteoporotics to determine response to therapy. There were 17 patients with normal menopause (NM), 4 with surgical menopause (SM), 3 with premature menopause (PM), and 18 with idiopathic osteoporoses (10). Intervals between DPA spine mineral estimation were 16.5 +- 5.2 mo. for NM, 14.3 +- 8.4 mo. for SM, 14.0 +- 7.5 mo. for PM and 16.7 +- 5.8 mo. for 10. Observed average percent change of spinemore » mineral under therapy for those intervals was 5.2 +- 7.9% for NM, +7.3 +- 1.7% for SM, -2.4 +- 6.3% for PM and +1.8 +- 12.3% for 10. Therapy invariably was with Ca, low dose Premarin in NM and PM, often with phosphates in IO, sometimes with thiazides, often with Vitamin D and with occasional other modalities, including NaF. The authors find DPA is a cost-effective way to measure osteopenia in the osteoporeses, document response to therapy, identify need for therapy change when there is continued bone loss under therapy, and to encourage the patient's compliance with long-term, complex therapies.« less

Effect of fixed-dose losartan/hydrochlorothiazide on brain natriuretic peptide in patients with hypertension.

PubMed

Shiga, Yuhei; Miura, Shin-ichiro; Mitsutake, Ryoko; Uehara, Yoshinari; Inoue, Asao; Saku, Keijiro

2012-03-01

Losartan/hydrochlorothiazide (HCTZ) (Preminent®) is a fixed-dose combination of angiotensin II receptor blocker (ARB) and the thiazide diuretic HCTZ that has consistently been shown to be more effective than either losartan or HCTZ. Little is known about the relationship between losartan/HCTZ and blood levels of brain natriuretic peptide (BNP). In this study, 44 patients with hypertension who were being treated with ARB were enrolled. The ARB was changed to losartan/HCTZ because of uncontrolled hypertension. Blood pressure (BP), pulse rate (PR), plasma levels of BNP and other biochemical parameters were analyzed at baseline and 6 and 12 months after the change from ARB. Of the total 44 patients, 33 (75%) achieved the target BP at 12 months. While there was no significant change in PR, systolic and diastolic BP were significantly reduced (-23 ± 3 mmHg and -10 ± 2 mmHg, respectively) during this period. Although there were no significant changes in biochemical parameters, plasma levels of BNP were significantly decreased, especially in patients who had higher levels of BNP at baseline, during this period. Losartan/HCTZ therapy significantly reduced not only BP but also plasma levels of BNP in patients with hypertension. These findings suggest that losartan/HCTZ might have cardioprotective effects in patients with higher levels of BNP.

Losartan/Hydrochlorothiazide: a review of its use in the treatment of hypertension and for stroke risk reduction in patients with hypertension and left ventricular hypertrophy.

PubMed

Keating, Gillian M

2009-06-18

Losartan/hydrochlorothiazide (HCTZ) [Hyzaar(R)] is a fixed-dose combination of the angiotensin II receptor antagonist (angiotensin receptor blocker [ARB]) losartan and the thiazide diuretic HCTZ. It is indicated for the treatment of hypertension (including as initial therapy in severe hypertension) and for stroke risk reduction in patients with hypertension and left ventricular hypertrophy (LVH). Losartan/HCTZ is an effective combination therapy, lowering blood pressure (BP) to a greater extent than losartan or HCTZ alone in patients with hypertension. Other ARB/HCTZ fixed-dose combinations generally lowered BP to a greater extent than losartan/HCTZ in patients with hypertension, although whether this translates into improvements in cardiovascular outcomes is not known. In the LIFE study, losartan-based therapy was associated with a lower incidence of cardiovascular morbidity and mortality than atenolol-based therapy, mainly as a result of a reduced risk of stroke; the incidence of new-onset diabetes mellitus was also lower with losartan-based therapy. Losartan/HCTZ is a well tolerated combination therapy. Thus, losartan/HCTZ remains an important option in the treatment of hypertension, as well as being indicated to reduce stroke risk in patients with hypertension and LVH.

Novel molecular variants of the Na-Cl cotransporter gene are responsible for Gitelman syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mastroianni, N.; De Fusco, M.; Casari, G.

1996-11-01

A hereditary defect of the distal tubule accounts for the clinical features of Gitelman syndrome (GS), an autosomal recessive disease characterized by hypokalemia, hypomagnesemia, metabolic alkalosis, and hypocalciuria. Recently, we cloned the cDNA coding for the human Na-Cl thiazide-sensitive cotransporter (TSC; also known as {open_quotes}NCCT{close_quotes} or {open_quotes}SLC12A3{close_quotes}) as a possible candidate for GS, and Simon et al., independently, described rotation in patients with GS. Now, we show 12 additional mutations consistent with a loss of function of the Na-Cl cotransporter in GS. Two missense replacements, R09W and P349L, are common to both studies and could represent ancient mutations. The othermore » mutations include three deletions, two insertions, and six missense mutations. When all mutations from both studies are considered, missense mutations seem to be more frequently localized within the intracellular domains of the molecule, rather than in transmembrane or extracellular domains. One family, previously reported as a GS form with dominant inheritance, has proved to be recessive, with the affected child being a compound heterozygote. A highly informative intragenic tetranucleotide marker, useful for molecular diagnostic studies, has been identified at the acceptor splice site of exon 9. 12 refs., 3 figs., 2 tabs.« less

Novel AQP2 mutation causing congenital nephrogenic diabetes insipidus: challenges in management during infancy.

PubMed

Rugpolmuang, Rottanat; Deeb, Asma; Hassan, Yousef; Deekajorndech, Tawatchai; Shotelersuk, Vorasuk; Sahakitrungruang, Taninee

2014-01-01

Congenital nephrogenic diabetes insipidus (NDI) is a rare inherited disorder, mostly caused by AVPR2 mutations. Less than 10% of cases are due to mutations in the aquaporin-2 (AQP2) gene. Diagnosis and management of this condition remain challenging especially during infancy. Here, we report two unrelated patients, a 6-month-old Thai boy and a 5-year-old Emirati girl, with a history of failure to thrive, chronic fever, polydipsia, and polyuria presented in early infancy. The results of water deprivation test were compatible with a diagnosis of NDI. The entire coding regions of the AVPR2 and AQP2 gene were amplified by polymerase chain reaction and sequenced. Patient 1 was homozygous for a novel missense AQP2 mutation p.G96E, inherited from both parents. Patient 2 harbored a previously described homozygous p.T126M mutation in the AQP2 gene. Both patients were treated with a combination of thiazide diuretics and amiloride. Patient 1 developed paradoxical hyponatremia and severe dehydration 2 weeks after medical treatment began. In conclusion, we report a novel mutation of the AQP2 gene and highlight an important role of genetic testing for definite diagnosis. Vigilant monitoring of the fluid status and electrolytes after beginning the therapy is mandatory in infants with NDI.

Primary stroke prevention and hypertension treatment: which is the first-line strategy?

PubMed

Ravenni, Roberta; Jabre, Joe F; Casiglia, Edoardo; Mazza, Alberto

2011-07-05

Hypertension (HT) is considered the main classic vascular risk factor for stroke and the importance of lowering blood pressure (BP) is well established. However, not all the benefit of antihypertensive treatment is due to BP reduction per se, as the effect of reducing the risk of stroke differs among classes of antihypertensive agents. Extensive evidences support that angiotensin-converting enzyme inhibitors (ACEI), angiotensin II receptor blockers (ARB), dihydropyridine calcium channel blockers (CCB) and thiazide diuretics each reduced risk of stroke compared with placebo or no treatment. Therefore, when combination therapy is required, a combination of these antihypertensive classes represents a logical approach. Despite the efficacy of antihypertensive therapy a large proportion of the population, still has undiagnosed or inadequately treated HT, and remain at high risk of stroke. In primary stroke prevention current guidelines recommend a systolic/diastolic BP goal of <140/<90 mmHg in the general population and <130/80 mmHg in diabetics and in subjects with high cardiovascular risk and renal disease. The recent release in the market of the fixed-dose combination (FDC) of ACEI or ARB and CCB should provide a better control of BP. However to confirm the efficacy of the FDC in primary stroke prevention, clinical intervention trials are needed.

Safety and tolerability of azilsartan medoxomil in subjects with essential hypertension: a one-year, phase 3, open-label study.

PubMed

Handley, Alison; Lloyd, Eric; Roberts, Andrew; Barger, Bruce

2016-01-01

This 56-week phase 3, open-label, treat-to-target study, involving 2 consecutive, non-randomized cohorts, evaluated the safety and tolerability of azilsartan medoxomil (AZL-M) in essential hypertension (mean baseline blood pressure [BP] 152/100 mmHg). All subjects (n = 669) initiated AZL-M 40 mg QD, force-titrated to 80 mg QD at week 4, if tolerated. From week 8, subjects could receive additional medications, starting with chlorthalidone (CLD) 25 mg QD (Cohort 1) or hydrochlorothiazide (HCTZ) 12.5-25 mg QD (Cohort 2), if required, to reach BP targets. Adverse events (AEs) were reported in 75.9% of subjects overall in the two cohorts (73.8% Cohort 1, 78.5% Cohort 2). The most common AEs were dizziness (14.3%), headache (9.9%) and fatigue (7.2%). Transient serum creatinine elevations were more frequent with add-on CLD. Clinic systolic/diastolic BP (observed cases at week 56) decreased by 25.2/18.4 mmHg (Cohort 1) and 24.2/17.9 mmHg (Cohort 2). These results demonstrate that AZL-M is well tolerated over the long term and provides stable BP improvements when used in a treat-to-target BP approach with thiazide-type diuretics.

Hypercalciuric Bone Disease

NASA Astrophysics Data System (ADS)

Favus, Murray J.

2008-09-01

Hypercalciuria plays an important causal role in many patients with calcium oxalate (CaOx) stones. The source of the hypercalciuria includes increased intestinal Ca absorption and decreased renal tubule Ca reabsorption. In CaOx stone formers with idiopathic hypercalciuria (IH), Ca metabolic balance studies have revealed negative Ca balance and persistent hypercalciuria in the fasting state and during low dietary Ca intake. Bone resorption may also contribute to the high urine Ca excretion and increase the risk of bone loss. Indeed, low bone mass by DEXA scanning has been discovered in many IH patients. Thiazide diuretic agents reduce urine Ca excretion and may increase bone mineral density (BMD), thereby reducing fracture risk. Dietary Ca restriction that has been used unsuccessfully in the treatment of CaOx nephrolithiasis in the past may enhance negative Ca balance and accelerate bone loss. DEXA scans may demonstrate low BMD at the spine, hip, or forearm, with no predictable pattern. The unique pattern of bone histologic changes in IH differs from other causes of low DEXA bone density including postmenopausal osteoporosis, male hypogonadal osteoporosis, and glucocorticoid-induced osteoporosis. Hypercalciuria appears to play an important pathologic role in the development of low bone mass, and therefore correction of urine Ca losses should be a primary target for treatment of the bone disease accompanying IH.

Advertising of antihypertensive medicines and prescription sales in Australia.

PubMed

Vitry, A; Lai, Y H

2009-11-01

Drug promotion is one of the main factors that influence prescribing practices, but there are limited data available to quantify the relationship between drug advertising and prescription sales. To investigate the relationship between advertising for antihypertensive medicines and prescription sales in Australia between 1993 and 2002. Retrospective observational study. Advertising trends were monitored by counting the number of advertisements published in three Australian medical journals. Monthly prescription dispensing data were obtained from Drug Utilisation Sub-Committee and expressed as numbers of defined daily doses/1000 inhabitants/day. Linear regression and cross-correlations of time series were used in the analysis. The drug classes the most heavily advertised, angiotensin-converting enzyme inhibitors and calcium channel blockers, were also the most prescribed during the study period, while the drugs the least advertised, thiazide diuretics and beta-blockers, were the least used. In 5 of the 7 main antihypertensive classes, the product the most advertised was also the most prescribed. Other factors, such as the publication of large clinical trials, may have also influenced prescribing patterns. Prescription sales of antihypertensives in Australia are correlated with promotional advertising. The newest and most expensive medicines may be chosen over older effective drugs by prescribers. New policies on drug promotion control need to be developed.

Study of Acute Kidney Injury on 309 Hypertensive Inpatients with ACEI/ARB - Diuretic Treatment.

PubMed

Chen, Qiaochao; Zhu, Shaofang; Liao, Jianjun; He, Wen

2018-06-01

The present study investigated risk factors for acute kidney injury (AKI) in patients found to be hypertensive during hospitalization who were prescribed angiotensin converting enzyme inhibitors (ACEI)/angiotensin receptor antagonists (ARB) + diuretic combinations, in order to determine which type of diuretic or combination of diuretics used in ACE/ARB-treated patients leads to a higher risk of acute kidney injury. Data on basic information, medical history, diagnostic information and medications prescribed were obtained from the patients' medical records. Retrospective analysis of potential risk factors and ACEI/ARB + diuretic use with AKI was performed. Multivariate analysis showed initial risk factors for AKI to be chronic kidney disease and poor cardiac function. In univariate analysis, patients whose baseline serum creatinine was between 115 and 265 μmol/L also had a higher risk of AKI. The combination of furosemide and spironolactone produced only approximately a third of the risk of AKI as the combination of hydrochlorothiazide and spironolactone. Chronic kidney disease and poor cardiac function are major risk factors for AKI in hypertensive inpatients using ACEI/ARB + diuretic therapy. The combination of thiazide diuretic and aldosterone antagonist had a higher risk of AKI than other single diuretics or diuretic combinations. Copyright © 2017 National Medical Association. Published by Elsevier Inc. All rights reserved.

Shoshin beriberi induced by long-term administration of diuretics: a case report.

PubMed

Misumida, Naoki; Umeda, Hisashi; Iwase, Mitsunori

2014-01-01

Previous studies have suggested that diuretic therapy for heart failure may lead to thiamine deficiency due to the increased urinary thiamine excretion. Herein, we present the case of a 61-year-old man with shoshin beriberi, a fulminant form of wet beriberi, induced by long-term diuretic therapy. The patient had a history of heart failure with preserved ejection fraction and was receiving furosemide and trichlormethiazide therapy. He presented with worsening exertional dyspnea and was admitted for heart failure exacerbation. His condition failed to improve even after intensive treatment. A hemodynamic evaluation with the Swan-Ganz catheter revealed high-output heart failure with low peripheral vascular resistance. Thiamine was administered for suspected shoshin beriberi; his hemodynamic status improved dramatically within the next six hours. The serum thiamine level was below the normal range; the patient was therefore diagnosed with shoshin beriberi. The common causes of thiamine deficiency were not identified. Long-term diuretic therapy with furosemide and thiazide was thought to have played a major role in the development of thiamine deficiency. This case illustrates the importance of considering wet beriberi as a possible cause of heart failure exacerbation in patients taking diuretics, even when the common thiamine deficiency causes are not identified with history-taking.

Medications not intended for treatment of dyslipidemias and with a variable effect on lipids.

PubMed

Whayne, Thomas F; Mukherjee, Debabrata

2014-01-01

Many therapeutically active medications have significant side effects, some of which can compromise the intended therapeutic goal. The development of plasma lipid abnormalities or a dyslipidemia as the result of a medication intended for an unrelated effect has been reported. Human immunodeficiency virus (HIV) infection can cause dyslipidemia as can the medications used to treat this infection. Such dyslipidemia can be a significant problem made more relevant by the already increased risk of cardiovascular (CV) disease faced by these patients. Some hypoglycemic medications used to treat diabetes can also be associated with dyslipidemia, most notably rosiglitazone. Antihypertensive medications are intended to decrease CV risk but are not free of dyslipidemia problems with thiazides able to cause hypertriglyceridemia and older beta-blockers without an alpha-blocking effect associated with moderate plasma lipid abnormalities and altered glucose metabolism. Estrogen administered orally can be associated with a severe hypertriglyceridemia. Currently-used antipsychotic medications have a significant association with hypertriglyceridemia. Clinicians must be aware of the dyslipidemias caused by these medications and know how to manage them, even treating a secondary dyslipidemia with another medication as in the case of HIV infection rather than trying to switch treatment of the infection in many cases. Mention is also made of lipid lowering effects of medications intended for other purposes (e.g. angiotensin receptor blockers and orlistat).

Risk Factors for Gout and Prevention: A Systematic Review of the Literature

PubMed Central

Singh, Jasvinder A.; Reddy, Supriya G.; Kundukulam, Joseph

2014-01-01

Purpose Our objective was to perform a systematic review of risk factors and prevention of gout. We searched Medline for fully published reports in English using keywords including but not limited to “gout”, “epidemiology”, “primary prevention”, “secondary prevention”, “risk factors’. Data from relevant articles meeting inclusion criteria was extracted using standardized forms. Main Findings Of the 751 titles and abstracts, 53 studies met the criteria and were included in the review. Several risk factors were studied. Alcohol consumption increased the risk of incident gout, especially beer and hard liquor. Several dietary factors increased the risk of incident gout, including meat intake, seafood intake, sugar sweetened soft drinks, and consumption of foods high in fructose. Diary intake, folate intake and coffee consumption were each associated with a lower risk of incident gout and in some cases a lower rate of gout flares. Thiazide and loop diuretics were associated with higher risk of incident gout and higher rate of gout flares. Hypertension, renal insufficiency, hypertriglyceridemia, hypercholesterolemia, hyperuricemia, diabetes, obesity and early menopause were each associated with a higher risk of incident gout and/or gout flares. Summary Several dietary risk factors for incident gout and gout flares are modifiable. Prevention and optimal management of comorbidities is likely to decreased risk of gout. Research in preventive strategies for the treatment of gout is needed. PMID:21285714

No relation between vitamin D status and physical performance in the oldest old: results from the Belfrail study.

PubMed

Matheï, Catharina; Van Pottelbergh, Gijs; Vaes, Bert; Adriaensen, Wim; Gruson, Didier; Degryse, Jean-Marie

2013-03-01

vitamin D deficiency is a well-known cause of bone loss and fractures but its association, especially among the oldest old, with muscle weakness is less obvious. to investigate the relationship between 25-hydroxyvitamin D (25-OHD) and muscle performance in persons aged 80 years and older. baseline results of the Belfrail study, a prospective, population-based cohort study were used to study balance, grip strength and gait speed in relation to 25-OHD serum levels in 367 subjects. a sufficient 25-OHD serum level of 30 ng/ml or more was found in 12.8% of the population. The prevalence of vitamin deficiency (20-29 ng/ml), insufficiency (10-19 ng/ml) and severe insufficiency (<10 ng/ml) was 21.5, 33 and 32.7%, respectively. No significant relation between balance, gait speed and grip strength, and serum 25-OHD was detected neither in bivariate analysis nor after adjustment for age, gender, level of education, institutionalisation, smoking status, body mass index, co-morbidity, level of activity, season, CRP, renal function, serum calcium parathyroid hormone levels, vitamin D intake and use of loop or thiazide diuretics. in this cohort of octogenarians vitamin D deficiency was highly prevalent. We could not confirm the findings of previous studies showing an association between serum 25-OHD and physical performance in elderly.

Prescription patterns and adequacy of blood pressure control among adult hypertensive patients in Kenya; findings and implications.

PubMed

Mbui, Jennifer M; Oluka, Margaret N; Guantai, Eric M; Sinei, Kipruto A; Achieng, Loice; Baker, Amanj; Jande, Mary; Massele, Amos; Godman, Brian

2017-11-01

Hypertension is a major cause of global morbidity and mortality, with high prevalence rates in Africa including Kenya. Consequently, it is imperative to understand current treatment approaches and their effectiveness in practice. Currently, there is paucity of such data in Kenya, which is a concern. The aim is to describe prescribing patterns and adequacy of blood pressure (BP) control in adult hypertensive patients to guide future practice. Retrospective study of patients attending a sub-county outpatient clinic combined with qualitative interviews. 247 hypertensive patients, predominantly female, mean age 55.8 years on antihypertensive therapy for 1-5 years, were analyzed. ACEIs and thiazide diuretics were the most commonly prescribed drugs, mainly as combination therapy. Treatment typically complied with guidelines, mainly for stage 2 hypertension (75%). BP control was observed in 46% of patients, with a significant reduction in mean systolic (155 to 144 mmHg) and diastolic (91 to 83 mmHg) BP (P < 0.001). Patients on ≥2 antihypertensive drugs were more likely to have uncontrolled BP (OR:1.9, p = 0.021). Encouragingly good adherence to guidelines was helped by training. Poor blood pressure control in the majority needs to be addressed. Additional training of prescribers and follow-up of measures to improve BP control will be introduced and followed up.

Pharmacotherapy-Based Problems in the Management of Diabetes Mellitus: Needs Much More to be Done!

PubMed Central

Ali, N; Shah, SWA; Khan, J; Rehman, S; Imran, M; Hussian, I; Shehbaz, N; Jamshed, H; Khan, S

2010-01-01

A total of 856 diabetic patients were evaluated for pharmacotherapy-based problems like for possible drug interactions, adverse drug reactions, and other mismatches, if any. Poor correlation between the advised insulin therapy and patients’ fasting blood glucose levels (12%, n=103) was observed. To most of the patients (41.66%, n= 357), insulin therapy was advised in combination with glucocorticoides, thiazides diuretics, and propranolol. Prescribing beta blocker (propranolol) with insulin is contraindicated. The higher incidence of diabetic foot patients was in the mean age of 57±3.4 years that was controlled with combination therapy of insulin and oral antidiabetics (63.0%, n=516). 11.1% of the treated patients could not take the prescribed therapy due to poor acceptance of insulin therapy due to its syringe needle prick. 41.66% risks of potential drug interactions, 7.93% adverse drug reactions, and 6.6% mismatches were recorded, as per the international approved algorithm, for managing a diabetes mellitus that reflects poor health care system. All these events necessitate for coordinating with other health professionals to make the therapy safer in the better interest of the patients. It is concluded that in practice prescribing pattern carries more risks for patients. It is imperative to improve the practice of pharmacotherapeutics rather than to practice in routine. PMID:21042492

Antihypertensive prescribing--a survey of general practice supervisors and registrars.

PubMed

Eastman, Peter

2008-11-01

Hypertension is a common problem in general practice. Prescribing guidelines vary, but generally favour thiazide diuretics as first line treatment for uncomplicated essential hypertension. This study looks at antihypertensive prescribing habits of primary care practitioners and their knowledge of prescribing guideline recommendations. General practitioner supervisors and registrars from the Sydney Institute of General Practice Education and Training completed an online survey between April and July 2007. In response to a clinical vignette, participants indicated which agent they would use as first line therapy. In addition, they described what they knew about existing prescribing guidelines for essential hypertension. One hundred and thirty-eight surveys were sent and 31 were returned completed. Angiotensin converting enzyme inhibitors were favoured as first line agents. Most believed current guidelines recommend more than one class of antihypertensive agent as appropriate for the initiation of single agent therapy. Angiotensin converting enzyme inhibitors were nominated most often as first line treatments recommended by guidelines. The study is limited by a small sample size, a low response rate and the fact that participants all came from a similar location. Prescribing habits in the study group were not consistent with two out of three Australian guidelines on management of hypertension. Further research may allow generalisation to the wider Australian general practice community and indicate underlying reasons for this inconsistency. Hypertension management is an important educational topic for general practice registrars and GPs.

Effectiveness of Treatment Modalities on Kidney Stone Recurrence.

PubMed

Zisman, Anna L

2017-10-06

Nephrolithiasis is highly prevalent across all demographic groups in the Western world and beyond, and its incidence rates are rising. In addition to the morbidity of the acute event, stone disease often becomes a lifelong problem that requires preventative therapy to diminish ongoing morbidity. Across the majority of stone types, increased fluid intake and targeted dietary modifications are mainstays of therapy. Specific dietary interventions associated with reduced calcium stone risk include adequate dietary calcium intake and restriction of sodium, protein, and oxalate intake, among others. Pharmaceutical therapy may be required if lifestyle changes are insufficient to minimize risk of stone recurrence, and must be targeted to the specific metabolic abnormalities portending risk for a given patient. Therapeutic options for idiopathic calcium stone disease include thiazides, citrate salts, and uric acid-lowering agents. Alkali salts are also the treatment of choice for uric acid stone disease. Management of struvite stone disease is largely surgical, but acetohydroxamic acid is a proven second line therapy. Cystinuria requires lifestyle modifications and may call for thiol-binding agents. Significant heterogeneity of the clinical population with stone disease has previously limited opportunities for large randomized controlled trials. However, as clinical phenotypes and genotypes are increasingly clarified, there are mounting opportunities for targeted randomized controlled trials in stone prevention. In the meantime, the currently available evidence for both lifestyle and pharmacologic interventions is reviewed herein. Copyright © 2017 by the American Society of Nephrology.

Potassium Intake, Bioavailability, Hypertension, and Glucose Control

PubMed Central

Stone, Michael S.; Martyn, Lisa; Weaver, Connie M.

2016-01-01

Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60–100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health. PMID:27455317

Potassium Intake, Bioavailability, Hypertension, and Glucose Control.

PubMed

Stone, Michael S; Martyn, Lisa; Weaver, Connie M

2016-07-22

Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60-100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health.

Cooperative mechanisms involved in chronic antidiuretic response to bendroflumethiazide in rats with lithium-induced nephrogenic diabetes insipidus.

PubMed

Moosavi, S M S; Karimi, Z

2014-03-01

Previous studies of central diabetes insipidus suggested that thiazides acutely exerted a paradoxical antidiuresis by either indirectly activating volume-homeostatic reflexes to decrease distal fluid-delivery, or directly stimulating distal water-reabsorption. This study investigated whether the direct and indirect actions of bendroflumethiazide (BFTZ) simultaneously cooperated and also whether the renal nerves were involved in inducing long-term antidiuresis in nephrogenic diabetes insipidus (NDI). BFTZ or vehicle was gavaged into bilateral renal denervated and innervated rats with lithium-induced NDI for 10 days, constituting four groups. At one day before (D0) and one, five and ten days after starting administration of BFTZ or vehicle, rats were placed in metabolic cages to collect urine for 6 hours. BFTZ-treatment in both renal innervated and denervated rats caused equivalent reductions in urine-flow, creatinine clearance, lithium clearance and free-water clearance, but rises in urine-osmolality, fractional proximal reabsorption and fractional distal reabsorption at all days compared to D0, as well as to those of their relevant vehicle-received group. Therefore, the chronic antidiuretic response to BFTZ in conscious NDI rats was exerted through a concomitant cooperation of its direct distal effect of stimulating water-reabsorption and its indirect effect of reducing distal fluid-delivery by activating volume-homeostatic mechanisms, which appeared independent of the renal nerves.

Longitudinal Average Attributable Fraction as a Method for Studying Time-Varying Conditions and Treatments on Recurrent Self-rated Health: The Case of Medications in Older Adults with Multiple Chronic Conditions

PubMed Central

Allore, Heather G.; Zhan, Yilei; Tinetti, Mary; Trentalange, Mark; McAvay, Gail

2015-01-01

Purpose The objective is to modify the longitudinal extension of the average attributable fraction (LE-AAF) for recurrent outcomes with time-varying exposures and control for covariates. Methods We included Medicare Current Beneficiary Survey participants with two or more chronic conditions enrolled from 2005-2009 with follow-up through 2011. Nine time-varying medications indicated for nine time-varying common chronic conditions and 14 out of 18 forward-selected participant characteristics were used as control variables in the generalized estimating equations step of the LE-AAF to estimate associations with the recurrent universal health outcome self-rated health (SRH). Modifications of the LE-AAF were made to accommodate these indicated medication-condition interactions and covariates. Variability was empirically estimated by bias-corrected and accelerated bootstrapping. Results In the adjusted LE-AAF, thiazide, warfarin and clopidogrel had significant contributions of 1.2%, 0.4%, 0.2% respectively to low (poor or fair) SRH; while there were no significant contributions of the other medications to SRH. Hyperlipidemia significantly contributed 4.6% to high SRH. All the other conditions except atrial fibrillation contributed significantly to low SRH. Conclusions Our modifications to the LE-AAF method apply to a recurrent binary outcome with time-varying factors accounting for covariates. PMID:26033374

Coffee-associated osteoporosis offset by daily milk consumption. The Rancho Bernardo Study.

PubMed

Barrett-Connor, E; Chang, J C; Edelstein, S L

1994-01-26

To describe the association of lifetime intake of caffeinated coffee, in cup-years, to bone mineral density (BMD) of the hip and spine in postmenopausal women; and to determine the effect of regular milk intake on this association. Women from an established epidemiologic cohort had measures of BMD and gave a medical and behavioral history that included caffeinated coffee and daily milk intake between the ages of 12 and 18 years, 20 and 50 years, and 50 years of age and older. A community-based population of older women, Rancho Bernardo, Calif. All 980 postmenopausal women aged 50 to 98 years (mean age, 72.7 years) who participated between 1988 and 1991. Bone density at the hip and lumbar spine measured by dual energy x-ray absorptiometry. There was a statistically significant graded association between increasing lifetime intake of caffeinated coffee and decreasing BMD at both the hip and spine, independent of age, obesity, parity, years since menopause, and the use of tobacco, alcohol, estrogen, thiazides, and calcium supplements. Bone density did not vary by lifetime coffee intake in women who reported drinking at least one glass of milk per day during most of their adult lives. Lifetime caffeinated coffee intake equivalent to two cups per day is associated with decreased bone density in older women who do not drink milk on a daily basis.

Low bioavailable testosterone levels predict future height loss in postmenopausal women.

PubMed

Jassal, S K; Barrett-Connor, E; Edelstein, S L

1995-04-01

The objective of this study was to examine the relation of endogenous sex hormones to subsequent height loss in postmenopausal women, in whom height loss is usually a surrogate for osteoporotic vertebral fractures. This was a prospective, community-based study. The site chosen was Rancho Bernardo, an upper middle class community in Southern California. A total of 170 postmenopausal women participated, aged 55-80 years. None of them were taking exogenous estrogen between 1972 and 1974. Plasma was obtained for sex hormone and sex hormone-binding globulin (SHBG) assays. Estradiol/SHBG and testosterone/SHBG ratios were used to estimate biologically available hormone levels; bioavailable (non-SHBG-bound) testosterone was measured directly in 60 women. Height loss was based on height measurements taken 16 years apart. Height loss was strongly correlated with age (p = 0.001). These women lost an average 0.22 cm/year in height. Neither estrone nor estradiol levels were significantly and independently related to height loss. Both estimated bioavailable testosterone (testosterone/SHBG ratio) and measured bioavailable testosterone levels predicted future height loss (p = 0.02 and 0.08, respectively) independent of age, obesity, cigarette smoking, alcohol intake, and use of thiazides and estrogen. We conclude that bioavailable testosterone is an independent predictor of height loss in elderly postmenopausal women. The reduced height loss is compatible with a direct effect of testosterone on bone mineral density or bone remodeling.

Cardiovascular benefits associated with higher dietary K+ vs. lower dietary Na+: evidence from population and mechanistic studies

PubMed Central

Veiras, Luciana C.; Guevara, Claire A.; Ralph, Donna L.

2017-01-01

The World Health Organization ranks hypertension the leading global risk factor for disease, specifically, cardiovascular disease. Blood pressure (BP) is higher in Westernized populations consuming Na+-rich processed foods than in isolated societies consuming K+-rich natural foods. Evidence suggests that lowering dietary Na+ is particularly beneficial in hypertensive individuals who consume a high-Na+ diet. Nonetheless, numerous population studies demonstrate a relationship between higher dietary K+, estimated from urinary excretion or dietary recall, and lower BP, regardless of Na+ intake. Interventional studies with K+ supplementation suggest that it provides a direct benefit; K+ may also be a marker for other beneficial components of a “natural” diet. Recent studies in rodent models indicate mechanisms for the K+ benefit: the distal tubule Na+-Cl− cotransporter (NCC) controls Na+ delivery downstream to the collecting duct, where Na+ reabsorbed by epithelial Na+ channels drives K+ secretion and excretion through K+ channels in the same region. High dietary K+ provokes a decrease in NCC activity to drive more K+ secretion (and Na+ excretion, analogous to the actions of a thiazide diuretic) whether Na+ intake is high or low; low dietary K+ provokes an increase in NCC activity and Na+ retention, also independent of dietary Na+. Together, the findings suggest that public health efforts directed toward increasing consumption of K+-rich natural foods would reduce BP and, thus, cardiovascular and kidney disease. PMID:28174181

Safety and tolerability of azilsartan medoxomil in subjects with essential hypertension: a one-year, phase 3, open-label study

PubMed Central

Handley, Alison; Lloyd, Eric; Roberts, Andrew; Barger, Bruce

2016-01-01

Abstract This 56-week phase 3, open-label, treat-to-target study, involving 2 consecutive, non-randomized cohorts, evaluated the safety and tolerability of azilsartan medoxomil (AZL-M) in essential hypertension (mean baseline blood pressure [BP] 152/100 mmHg). All subjects (n = 669) initiated AZL-M 40 mg QD, force-titrated to 80 mg QD at week 4, if tolerated. From week 8, subjects could receive additional medications, starting with chlorthalidone (CLD) 25 mg QD (Cohort 1) or hydrochlorothiazide (HCTZ) 12.5–25 mg QD (Cohort 2), if required, to reach BP targets. Adverse events (AEs) were reported in 75.9% of subjects overall in the two cohorts (73.8% Cohort 1, 78.5% Cohort 2). The most common AEs were dizziness (14.3%), headache (9.9%) and fatigue (7.2%). Transient serum creatinine elevations were more frequent with add-on CLD. Clinic systolic/diastolic BP (observed cases at week 56) decreased by 25.2/18.4 mmHg (Cohort 1) and 24.2/17.9 mmHg (Cohort 2). These results demonstrate that AZL-M is well tolerated over the long term and provides stable BP improvements when used in a treat-to-target BP approach with thiazide-type diuretics. PMID:26817604

Spironolactone reduces severity of obstructive sleep apnoea in patients with resistant hypertension: a preliminary report.

PubMed

Gaddam, K; Pimenta, E; Thomas, S J; Cofield, S S; Oparil, S; Harding, S M; Calhoun, D A

2010-08-01

Obstructive sleep apnoea (OSA) and hyperaldosteronism are very common in subjects with resistant hypertension. We hypothesized that aldosterone-mediated chronic fluid retention may influence OSA severity in patients with resistant hypertension. We tested this in an open-label evaluation by assessing the changes in the severity of OSA in patients with resistant hypertension after treatment with spironolactone. Subjects with resistant hypertension (clinical blood pressure (BP) >or=140/90 mm Hg on >or=3 antihypertensive medications, including a thiazide diuretic and OSA (defined as an apnoea-hypopnoea index (AHI) >or=15) had full diagnostic, polysomnography before and 8 weeks after spironolactone (25-50 mg a day) was added to their ongoing antihypertensive therapy. In all, 12 patients (mean age 56 years and body mass index 36.8 kg m(-2)) were evaluated. After treatment with spironolactone, the AHI (39.8+/-19.5 vs 22.0+/-6.8 events/h; P<0.05) and hypoxic index (13.6+/-10.8 vs 6.7+/-6.6 events/h; P<0.05), weight and clinic and ambulatory BP were significantly reduced. Plasma renin activity (PRA) and serum creatinine were significantly higher. This study provides preliminary evidence that treatment with a mineralocorticoid receptor antagonist substantially reduces the severity of OSA. If confirmed in a randomized assessment, it will support aldosterone-mediated chronic fluid retention as an important mediator of OSA severity in patients with resistant hypertension.

Pathogenesis of hypokalemia in autosomal dominant hypocalcemia type 1.

PubMed

Kamiyoshi, Naohiro; Nozu, Kandai; Urahama, Yoshimichi; Matsunoshita, Natsuki; Yamamura, Tomohiko; Minamikawa, Shogo; Ninchoji, Takeshi; Morisada, Naoya; Nakanishi, Koichi; Kaito, Hiroshi; Iijima, Kazumoto

2016-04-01

Autosomal dominant hypocalcemia type 1 (ADH1) is a relatively rare endocrine disorder characterized by hypocalcemia and inadequate parathyroid hormone secretion. ADH is caused by activating mutations in the calcium-sensing receptor (CaSR) gene, CASR. CaSR plays a crucial role in calcium and magnesium homeostasis in the kidney. ADH may be accompanied by hypokalemia and metabolic alkalosis when it is classified as type V Bartter syndrome. However, the mechanism underlying hypokalemia in this disease is unclear. We investigated a 33-year-old woman with hypocalcemia and hypoparathyroidism since childhood, whose mother also had hypocalcemia and hypoparathyroidism, but with no clinical symptoms. Blood examinations showed hypokalemia and metabolic alkalosis in the patient, but not her mother. We conducted mutation analysis and diuretic tests to clarify the patient's and her mother's diagnosis and to investigate the onset mechanism of hypokalemia in ADH1. We also determined the localization of CaSR in the kidney by immunohistochemistry. We detected a known gain-of-function mutation in CASR in both the patient and her mother. Diuretic tests revealed a response to furosemide and no reaction to thiazide in the patient, although the mother responded well to both diuretics. CaSR co-localized with the Na(+)-Cl(-) cotransporter (NCCT) on distal tubular epithelial cells. These results indicate that the NCCT in the distal convoluted tubule was secondarily affected in this patient. We conclude that the main pathogenesis of secondary hypokalemia in ADH1 in this patient was secondary NCCT dysfunction.

Genome-wide meta-analysis of SNP-by9-ACEI/ARB and SNP-by-thiazide diuretic and effect on serum potassium in cohorts of European and African ancestry.

PubMed

Irvin, Marguerite R; Sitlani, Colleen M; Noordam, Raymond; Avery, Christie L; Bis, Joshua C; Floyd, James S; Li, Jin; Limdi, Nita A; Srinivasasainagendra, Vinodh; Stewart, James; de Mutsert, Renée; Mook-Kanamori, Dennis O; Lipovich, Leonard; Kleinbrink, Erica L; Smith, Albert; Bartz, Traci M; Whitsel, Eric A; Uitterlinden, Andre G; Wiggins, Kerri L; Wilson, James G; Zhi, Degui; Stricker, Bruno H; Rotter, Jerome I; Arnett, Donna K; Psaty, Bruce M; Lange, Leslie A

2018-06-01

We evaluated interactions of SNP-by-ACE-I/ARB and SNP-by-TD on serum potassium (K+) among users of antihypertensive treatments (anti-HTN). Our study included seven European-ancestry (EA) (N = 4835) and four African-ancestry (AA) cohorts (N = 2016). We performed race-stratified, fixed-effect, inverse-variance-weighted meta-analyses of 2.5 million SNP-by-drug interaction estimates; race-combined meta-analysis; and trans-ethnic fine-mapping. Among EAs, we identified 11 significant SNPs (P < 5 × 10 -8 ) for SNP-ACE-I/ARB interactions on serum K+ that were located between NR2F1-AS1 and ARRDC3-AS1 on chromosome 5 (top SNP rs6878413 P = 1.7 × 10 -8 ; ratio of serum K+ in ACE-I/ARB exposed compared to unexposed is 1.0476, 1.0280, 1.0088 for the TT, AT, and AA genotypes, respectively). Trans-ethnic fine mapping identified the same group of SNPs on chromosome 5 as genome-wide significant for the ACE-I/ARB analysis. In conclusion, SNP-by-ACE-I /ARB interaction analyses uncovered loci that, if replicated, could have future implications for the prevention of arrhythmias due to anti-HTN treatment-related hyperkalemia. Before these loci can be identified as clinically relevant, future validation studies of equal or greater size in comparison to our discovery effort are needed.

Recruitment of participants through community pharmacies for a pharmacogenetic study of antihypertensive drug treatment.

PubMed

van Wieren-de Wijer, Diane B M A; Maitland-van der Zee, Anke-Hilse; de Boer, Anthonius; Stricker, Bruno H Ch; Kroon, Abraham A; de Leeuw, Peter W; Bozkurt, O; Klungel, Olaf H

2009-04-01

To describe the design, recruitment and baseline characteristics of participants in a community pharmacy based pharmacogenetic study of antihypertensive drug treatment. Participants enrolled from the population-based Pharmaco-Morbidity Record Linkage System. We designed a nested case-control study in which we will assess whether specific genetic polymorphisms modify the effect of antihypertensive drugs on the risk of myocardial infarction. In this study, cases (myocardial infarction) and controls were recruited through community pharmacies that participate in PHARMO. The PHARMO database comprises drug dispensing histories of about 2,000,000 subjects from a representative sample of Dutch community pharmacies linked to the national registrations of hospital discharges. In total we selected 31010 patients (2777 cases and 28233 controls) from the PHARMO database, of whom 15973 (1871 cases, 14102 controls) were approached through their community pharmacy. Overall response rate was 36.3% (n = 5791, 794 cases, 4997 controls), whereas 32.1% (n = 5126, 701 cases, 4425 controls) gave informed consent to genotype their DNA. As expected, several cardiovascular risk factors such as smoking, body mass index, hypercholesterolemia, and diabetes mellitus were more common in cases than in controls. Furthermore, cases more often used beta-blockers and calcium-antagonists, whereas controls more often used thiazide diuretics, ACE-inhibitors, and angiotensin-II receptor blockers. We have demonstrated that it is feasible to select patients from a coded database for a pharmacogenetic study and to approach them through community pharmacies, achieving reasonable response rates and without violating privacy rules.

Novel NCC mutants and functional analysis in a new cohort of patients with Gitelman syndrome.

PubMed

Glaudemans, Bob; Yntema, Helger G; San-Cristobal, Pedro; Schoots, Jeroen; Pfundt, Rolph; Kamsteeg, Erik-J; Bindels, René J; Knoers, Nine V A M; Hoenderop, Joost G; Hoefsloot, Lies H

2012-03-01

Gitelman syndrome (GS) is an autosomal recessive disorder characterized by hypokalemic metabolic alkalosis in conjunction with significant hypomagnesemia and hypocalciuria. The GS phenotype is caused by mutations in the solute carrier family 12, member 3 (SLC12A3) gene that encodes the thiazide-sensitive NaCl cotransporter (NCC). We analyzed DNA samples of 163 patients with a clinical suspicion of GS by direct sequencing of all 26 exons of the SLC12A3 gene. In total, 114 different mutations were identified, 31 of which have not been reported before. These novel variants include 3 deletions, 18 missense, 6 splice site and 4 nonsense mutations. We selected seven missense mutations to investigate their effect on NCC activity and plasma membrane localization by using the Xenopus laevis oocyte expression system. The Thr392Ile mutant did not display transport activity (probably class 2 mutation), while the Asn442Ser and Gln1030Arg NCC mutants showed decreased plasma membrane localization and consequently function, likely due to impaired trafficking (class 3 mutation). Even though the NaCl uptake was hampered for NCC mutants Glu121Asp, Pro751Leu, Ser475Cys and Tyr489His, the transporters reached the plasma membrane (class 4 mutation), suggesting an effect on NCC regulation or ion affinity. The present study shows the identification of 38 novel mutations in the SLC12A3 gene and provides insight into the mechanisms that regulate NCC.

The sodium chloride cotransporter (NCC) and epithelial sodium channel (ENaC) associate.

PubMed

Mistry, Abinash C; Wynne, Brandi M; Yu, Ling; Tomilin, Viktor; Yue, Qiang; Zhou, Yiqun; Al-Khalili, Otor; Mallick, Rickta; Cai, Hui; Alli, Abdel A; Ko, Benjamin; Mattheyses, Alexa; Bao, Hui-Fang; Pochynyuk, Oleh; Theilig, Franziska; Eaton, Douglas C; Hoover, Robert S

2016-10-01

The thiazide-sensitive sodium chloride cotransporter (NCC) and the epithelial sodium channel (ENaC) are two of the most important determinants of salt balance and thus systemic blood pressure. Abnormalities in either result in profound changes in blood pressure. There is one segment of the nephron where these two sodium transporters are coexpressed, the second part of the distal convoluted tubule. This is a key part of the aldosterone-sensitive distal nephron, the final regulator of salt handling in the kidney. Aldosterone is the key hormonal regulator for both of these proteins. Despite these shared regulators and coexpression in a key nephron segment, associations between these proteins have not been investigated. After confirming apical localization of these proteins, we demonstrated the presence of functional transport proteins and native association by blue native PAGE. Extensive coimmunoprecipitation experiments demonstrated a consistent interaction of NCC with α- and γ-ENaC. Mammalian two-hybrid studies demonstrated direct binding of NCC to ENaC subunits. Fluorescence resonance energy transfer and immunogold EM studies confirmed that these transport proteins are within appropriate proximity for direct binding. Additionally, we demonstrate that there are functional consequences of this interaction, with inhibition of NCC affecting the function of ENaC. This novel finding of an association between ENaC and NCC could alter our understanding of salt transport in the distal tubule. © 2016 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

Diagnosis, treatment, and prevention of gout.

PubMed

Hainer, Barry L; Matheson, Eric; Wilkes, R Travis

2014-12-15

Gout is characterized by painful joint inflammation, most commonly in the first metatarsophalangeal joint, resulting from precipitation of monosodium urate crystals in a joint space. Gout is typically diagnosed using clinical criteria from the American College of Rheumatology. Diagnosis may be confirmed by identification of monosodium urate crystals in synovial fluid of the affected joint. Acute gout may be treated with nonsteroidal anti-inflammatory drugs, corticosteroids, or colchicine. To reduce the likelihood of recurrent flares, patients should limit their consumption of certain purine-rich foods (e.g., organ meats, shellfish) and avoid alcoholic drinks (especially beer) and beverages sweetened with high-fructose corn syrup. Consumption of vegetables and low-fat or nonfat dairy products should be encouraged. The use of loop and thiazide diuretics can increase uric acid levels, whereas the use of the angiotensin receptor blocker losartan increases urinary excretion of uric acid. Reduction of uric acid levels is key to avoiding gout flares. Allopurinol and febuxostat are first-line medications for the prevention of recurrent gout, and colchicine and/or probenecid are reserved for patients who cannot tolerate first-line agents or in whom first-line agents are ineffective. Patients receiving urate-lowering medications should be treated concurrently with nonsteroidal anti-inflammatory drugs, colchicine, or low-dose corticosteroids to prevent flares. Treatment should continue for at least three months after uric acid levels fall below the target goal in those without tophi, and for six months in those with a history of tophi.

Management of diabetes insipidus in children

PubMed Central

Mishra, Garima; Chandrashekhar, Sudha Rao

2011-01-01

Diabetes Insipidus (DI) is a heterogeneous clinical syndrome of disturbance in water balance, characterized by polyuria (urine output > 4 ml/kg/hr), polydypsia (water intake > 2 L/m2/d) and failure to thrive. In children, Nephrogenic DI (NDI) is more common than Central DI (CDI), and is often acquired. The signs and symptoms vary with etiology, age at presentation and mode of onset. Neonates and infants with NDI are severely affected and difficult to treat. Diagnosis is based on the presence of high plasma osmolality and low urinary osmolality with significant water diuresis. Water deprivation test with vasopressin challenge, though has limitations, is done to differentiate NDI and CDI and diagnose their partial forms. Measurement of urinary aquaporin 2 and serum copeptin levels are being studied and show promising diagnostic potential. Magnetic Resonance Imaging (MRI) pituitary helps in the etiological diagnosis of CDI, absence of posterior pituitary bright signal being the pathognomic sign. If pituitary stalk thickening of < 2 mm is present, these children need to be monitored for evolving lesion. Neonates and young infants are better managed with fluids alone. Older children with CDI are treated with desmopressin. The oral form is safe, highly effective, with more flexibility of dosing and has largely replaced the intranasal form. In NDI besides treatment of the underlying cause, use of high calorie low solute diet and drugs to ameliorate water excretion (thiazide, amelioride, indomethacin) are useful. Children with NDI however well treated, remain short and have mental retardation on follow up. PMID:22029022

Unique chloride-sensing properties of WNK4 permit the distal nephron to modulate potassium homeostasis.

PubMed

Terker, Andrew S; Zhang, Chong; Erspamer, Kayla J; Gamba, Gerardo; Yang, Chao-Ling; Ellison, David H

2016-01-01

Dietary potassium deficiency activates thiazide-sensitive sodium chloride cotransport along the distal nephron. This may explain, in part, the hypertension and cardiovascular mortality observed in individuals who consume a low-potassium diet. Recent data suggest that plasma potassium affects the distal nephron directly by influencing intracellular chloride, an inhibitor of the with-no-lysine kinase (WNK)-Ste20p-related proline- and alanine-rich kinase (SPAK) pathway. As previous studies used extreme dietary manipulations, we sought to determine whether the relationship between potassium and NaCl cotransporter (NCC) is physiologically relevant and clarify the mechanisms involved. We report that modest changes in both dietary and plasma potassium affect NCC in vivo. Kinase assay studies showed that chloride inhibits WNK4 kinase activity at lower concentrations than it inhibits activity of WNK1 or WNK3. Also, chloride inhibited WNK4 within the range of distal cell chloride concentration. Mutation of a previously identified WNK chloride-binding motif converted WNK4 effects on SPAK from inhibitory to stimulatory in mammalian cells. Disruption of this motif in WNKs 1, 3, and 4 had different effects on NCC, consistent with the three WNKs having different chloride sensitivities. Thus, potassium effects on NCC are graded within the physiological range, which explains how unique chloride-sensing properties of WNK4 enable it to mediate effects of potassium on NCC in vivo. Copyright © 2015 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

STROKE OUTCOMES AMONG PARTICIPANTS RANDOMIZED TO CHLORTHALIDONE, AMLODIPINE OR LISINOPRIL IN ALLHAT

PubMed Central

Yamal, José-Miguel; Oparil, Suzanne; Davis, Barry R.; Alderman, Michael H.; Calhoun, David A.; Cushman, William C.; Fendley, Herbert F.; Franklin, Stanley S.; Habib, Gabriel B.; Pressel, Sara L.; Probstfield, Jeffrey L.; Sastrasinh, Sithiporn

2014-01-01

Background The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) was a randomized, double-blind, practice-based, active-control, comparative effectiveness trial in 33,357 high-risk hypertensive participants. Methods and Results ALLHAT compared cardiovascular disease outcomes in participants initially treated with angiotensin-converting enzyme inhibitor (lisinopril), calcium channel blocker (amlodipine), or thiazide-type diuretic (chlorthalidone). We report stroke outcomes in 1517 participants in-trial and 1596 additional participants during post-trial passive surveillance, for total follow-up of 8–13 years. Stroke rates were higher with lisinopril (6-year rate/100=6.4) than with chlorthalidone (5.8) or amlodipine (5.5) in-trial but not including post-trial (10-year rates/100=13.2 [chlorthalidone], 13.1[amlodipine], and 13.7 [lisinopril]). In- trial differences were driven by race (race-by-lisinopril/chlorthalidone interaction P=0.005, race-by-amlodipine/lisinopril interaction P=0.012) and gender (gender-by-lisinopril/amlodipine interaction P=0.041), separately. No treatment differences overall, or by race or gender, were detected over the 10-year period. No differences appeared among treatment groups in adjusted risk of all-cause mortality including post-trial for participants with nonfatal in-trial strokes. Conclusions Among Blacks and women, lisinopril was less effective in preventing stroke in-trial than either chlorthalidone or amlodipine, even after adjusting for differences in systolic blood pressure. These differences abated by the end of the post-trial period. PMID:25455006

Central and peripheral fat body mass have a protective effect on osteopenia or osteoporosis in adults and elderly?

PubMed

Freitas, P M S S; Garcia Rosa, M L; Gomes, A M; Wahrlich, V; Di Luca, D G; da Cruz Filho, R A; da Silva Correia, D M; Faria, C A; Yokoo, E M

2016-04-01

This cross-sectional study involves randomly selected men aged 50 to 99 years and postmenopausal women. Either central fat mass or peripheral fat mass were associated to osteoporosis or osteopenia independently from fat-free body mass and other confounding factors. Obesity and osteoporosis are public health problems that probably share common pathophysiological mechanisms. The question if body fat mass, central or peripheral, is protective or harmful for osteoporosis or osteopenia is not completely resolved. This study aims to investigate the association between osteoporosis or osteopenia, and fat body mass (central and peripheral) independently from fat-free body mass, in men aged 50 to 99 years old and postmenopausal women randomly selected in the community. This is a cross-sectional investigation with a random sample of registered population in Niterói Family Doctor Program (FDP), State of Rio de Janeiro, Brazil. Bone mineral density (BMD) and fat-free mass were assessed by dual X-ray absorptiometry (DXA). There was statistically significant bivariate association between bone loss with gender, age, skin color, alcohol consumption at risk dose, use of thiazide, fat-free body mass, and fat body mass (central and peripheral). In the multiple analysis of fat-free body mass, central and peripheral fat body mass showed an independent and protective effect on the presence of osteoporosis or osteopenia (p value <0.001). Since both obesity and osteoporosis are public health problems worldwide, strategies aimed at preventing both conditions should be encouraged during aging.

Ambiguities in the Guidelines for the Management of Arterial Hypertension: Indian Perspective with a Call for Global Harmonization.

PubMed

Rehan, Harmeet Singh; Grover, Abhinav; Hungin, A P S

2017-02-01

Many medical professional societies have formulated guidelines to treat hypertension, but there existed differences with respect to diagnosis, blood pressure (BP) targets, pharmacotherapy of hypertension, and grades of evidence. A MEDLINE search for hypertension guidelines was performed to compare Indian guidelines for hypertension (IGH) with these guidelines. A majority of the guidelines had consensus on the cutoff value (140/90 mmHg, recorded twice) to diagnose hypertension. The Joint National Committee 8 (JNC 8), IGH, Japanese Society of hypertension (JSH), Canadian Hypertension Education Program (CHEP), and American Society of Hypertension/International Society of Hypertension (ASH/ISH) guidelines provide a higher BP target for the elderly hypertensive populations, while the National Institute for Health and Care Excellence (NICE) and European Society of Hypertension (ESH) guidelines provided a lower BP target for the elderly patients. However, a meta-analysis showed benefits of having a systolic BP target of <130 mmHg for all patients. Treatment of hypertension according to JNC 8, NICE, and ASH/ISH guidelines varies among the black and the non-black population which recommended thiazide or calcium channel blockers for the black population. There is no special mention of pharmacotherapy or BP targets for the South Asian population in various guidelines including IGH despite evidence of higher risk of hypertension-associated complications in this population. It is suggested that all the available guidelines should be harmonized with highest level of evidence available to minimize ambiguities associated with management of hypertension.

Serum uric acid concentrations are directly associated with the presence of benign multiple sclerosis.

PubMed

Simental-Mendía, Esteban; Simental-Mendía, Luis E; Guerrero-Romero, Fernando

2017-09-01

It has been reported that patients with multiple sclerosis (MS) exhibit lower serum uric acid levels; however, the association between uric acid concentrations and benign MS (BMS) has not been assessed. Hence, the objective of the present study was to determine whether the serum concentrations of uric acid are associated with the presence of BMS. Men and non-pregnant women over 16 years of age with diagnosis of MS were enrolled in a cross-sectional study. Expanded Disability Status Scale score < 3, progression of disease ≤10 years, diabetes, renal or hepatic diseases, gout, malignancy, alcohol intake, and treatment with thiazide diuretics and/or acetylsalicylic acid were exclusion criteria. According to subtype of disease, the eligible patients were allocated into groups with BMS and other varieties of MS. A logistic regression analysis was conducted in order to evaluate the association between serum concentrations of uric acid and BMS. A total of 106 patients were included, 39 in the group with BMS and 67 in the group with other varieties of MS. The logistic regression analysis adjusted by age, sex, and disease duration showed that increased concentrations of uric acid, indeed within the physiological levels, are significantly associated with the presence of BMS (OR = 2.60; 95% CI: 1.55-4.38, p < 0.001). The results of the present study suggest that elevated concentrations of uric acid, indeed within the physiological range, are likely linked to the presence of BMS.

Evaluating the Safety and Tolerability of Sacubitril/Valsartan for HFrEF Managed Within a Pharmacist Clinic.

PubMed

Pogge, Elizabeth K; Davis, Lindsay E

2018-04-01

The objective of this research was to describe the use of pharmacist-managed sacubitril/valsartan therapy in a multi-center, outpatient cardiac group. Sacubitril/valsartan, an angiotensin receptor-neprilysin inhibitor (ARNi), is a novel agent for the treatment of heart failure. An ARNi is recommended by national guidelines to be used in place of angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) therapy for patients who remain symptomatic. A retrospective chart review was performed to identify patients initiated and fully titrated on sacubitril/valsartan therapy from July 7, 2015 to March 7, 2017. Fifty-two of the 72 symptomatic heart failure with reduced ejection fraction (HFrEF) patients prescribed sacubitril/valsartan during the 21-month period were included in this analysis. The average ejection fraction was 26%. The average age was 69 years. At baseline, 26.9% of patients were not on ACEi/ARB therapy and 13.5% were on target-dose therapy. After completing the uptitration process, the maximally tolerated dose of sacubitril/valsartan was 5.8% low-dose, 7.7% mid-dose, and 86.5% target-dose. Loop and thiazide diuretic use decreased significantly. There was a significant mean reduction in systolic blood pressure of 6 mmHg with no significant changes in serum creatinine, blood urea nitrogen, or potassium levels. With close monitoring and follow-up, ARNi therapy was a safe alternative to ACEi/ARB therapy for chronic symptomatic HFrEF when initiated within a pharmacist clinic.

Dietary potassium and the renal control of salt balance and blood pressure.

PubMed

Penton, David; Czogalla, Jan; Loffing, Johannes

2015-03-01

Dietary potassium (K(+)) intake has antihypertensive effects, prevents strokes, and improves cardiovascular outcomes. The underlying mechanism for these beneficial effects of high K(+) diets may include vasodilation, enhanced urine flow, reduced renal renin release, and negative sodium (Na(+)) balance. Indeed, several studies demonstrate that dietary K(+) intake induces renal Na(+) loss despite elevated plasma aldosterone. This review briefly highlights the epidemiological and experimental evidences for the effects of dietary K(+) on arterial blood pressure. It discusses the pivotal role of the renal distal tubule for the regulation of urinary K(+) and Na(+) excretion and blood pressure and highlights that it depends on the coordinated interaction of different nephron portions, epithelial cell types, and various ion channels, transporters, and ATPases. Moreover, we discuss the relevance of aldosterone and aldosterone-independent factors in mediating the effects of an altered K(+) intake on renal K(+) and Na(+) handling. Particular focus is given to findings suggesting that an aldosterone-independent downregulation of the thiazide-sensitive NaCl cotransporter significantly contributes to the natriuretic and antihypertensive effect of a K(+)-rich diet. Last but not least, we refer to the complex signaling pathways enabling the kidney to adapt its function to the homeostatic needs in response to an altered K(+) intake. Future work will have to further address the underlying cellular and molecular mechanism and to elucidate, among others, how an altered dietary K(+) intake is sensed and how this signal is transmitted to the different epithelial cells lining the distal tubule.

Refractory and Resistant Hypertension: Antihypertensive Treatment Failure versus Treatment Resistance

PubMed Central

2016-01-01

Resistant hypertension has for many decades been defined as difficult-to-treat hypertension in order to identify patients who may benefit from special diagnostic and/or therapeutic considerations. Recently, the term "refractory hypertension" has been proposed as a novel phenotype of antihypertensive failure, that is, patients whose blood pressure cannot be controlled with maximal treatment. Early studies of this phenotype indicate that it is uncommon, affecting less than 5% of patients with resistant hypertension. Risk factors for refractory hypertension include obesity, diabetes, chronic kidney disease, and especially, being of African origin. Patients with refractory are at high cardiovascular risk based on increased rates of known heart disease, prior stroke, and prior episodes of congestive heart failure. Mechanisms of refractory hypertension need exploration, but early studies suggest a possible role of heightened sympathetic tone as evidenced by increased office and ambulatory heart rates and higher urinary excretion of norepinephrine compared to patients with controlled resistant hypertension. Important negative findings argue against refractory hypertension being fluid dependent as is typical of resistant hypertension, including aldosterone levels, dietary sodium intake, and brain natriuretic peptide levels being similar or even less than patients with resistant hypertension and the failure to control blood pressure with use of intensive diuretic therapy, including both a long-acting thiazide diuretic and a mineralocorticoid receptor antagonist. Further studies, especially longitudinal assessments, are needed to better characterize this extreme phenotype in terms of risk factors and outcomes and hopefully to identify effective treatment strategies. PMID:27721847

The ClC-K2 Chloride Channel Is Critical for Salt Handling in the Distal Nephron.

PubMed

Hennings, J Christopher; Andrini, Olga; Picard, Nicolas; Paulais, Marc; Huebner, Antje K; Cayuqueo, Irma Karen Lopez; Bignon, Yohan; Keck, Mathilde; Cornière, Nicolas; Böhm, David; Jentsch, Thomas J; Chambrey, Régine; Teulon, Jacques; Hübner, Christian A; Eladari, Dominique

2017-01-01

Chloride transport by the renal tubule is critical for blood pressure (BP), acid-base, and potassium homeostasis. Chloride uptake from the urinary fluid is mediated by various apical transporters, whereas basolateral chloride exit is thought to be mediated by ClC-Ka/K1 and ClC-Kb/K2, two chloride channels from the ClC family, or by KCl cotransporters from the SLC12 gene family. Nevertheless, the localization and role of ClC-K channels is not fully resolved. Because inactivating mutations in ClC-Kb/K2 cause Bartter syndrome, a disease that mimics the effects of the loop diuretic furosemide, ClC-Kb/K2 is assumed to have a critical role in salt handling by the thick ascending limb. To dissect the role of this channel in detail, we generated a mouse model with a targeted disruption of the murine ortholog ClC-K2. Mutant mice developed a Bartter syndrome phenotype, characterized by renal salt loss, marked hypokalemia, and metabolic alkalosis. Patch-clamp analysis of tubules isolated from knockout (KO) mice suggested that ClC-K2 is the main basolateral chloride channel in the thick ascending limb and in the aldosterone-sensitive distal nephron. Accordingly, ClC-K2 KO mice did not exhibit the natriuretic response to furosemide and exhibited a severely blunted response to thiazide. We conclude that ClC-Kb/K2 is critical for salt absorption not only by the thick ascending limb, but also by the distal convoluted tubule. Copyright © 2016 by the American Society of Nephrology.

The ClC-K2 Chloride Channel Is Critical for Salt Handling in the Distal Nephron

PubMed Central

Hennings, J. Christopher; Andrini, Olga; Picard, Nicolas; Paulais, Marc; Huebner, Antje K.; Cayuqueo, Irma Karen Lopez; Bignon, Yohan; Keck, Mathilde; Cornière, Nicolas; Böhm, David; Jentsch, Thomas J.; Chambrey, Régine; Hübner, Christian A.

2017-01-01

Chloride transport by the renal tubule is critical for blood pressure (BP), acid-base, and potassium homeostasis. Chloride uptake from the urinary fluid is mediated by various apical transporters, whereas basolateral chloride exit is thought to be mediated by ClC-Ka/K1 and ClC-Kb/K2, two chloride channels from the ClC family, or by KCl cotransporters from the SLC12 gene family. Nevertheless, the localization and role of ClC-K channels is not fully resolved. Because inactivating mutations in ClC-Kb/K2 cause Bartter syndrome, a disease that mimics the effects of the loop diuretic furosemide, ClC-Kb/K2 is assumed to have a critical role in salt handling by the thick ascending limb. To dissect the role of this channel in detail, we generated a mouse model with a targeted disruption of the murine ortholog ClC-K2. Mutant mice developed a Bartter syndrome phenotype, characterized by renal salt loss, marked hypokalemia, and metabolic alkalosis. Patch-clamp analysis of tubules isolated from knockout (KO) mice suggested that ClC-K2 is the main basolateral chloride channel in the thick ascending limb and in the aldosterone-sensitive distal nephron. Accordingly, ClC-K2 KO mice did not exhibit the natriuretic response to furosemide and exhibited a severely blunted response to thiazide. We conclude that ClC-Kb/K2 is critical for salt absorption not only by the thick ascending limb, but also by the distal convoluted tubule. PMID:27335120

Personalised Single-Pill Combination Therapy in Hypertensive Patients: An Update of a Practical Treatment Platform.

PubMed

Volpe, Massimo; Tocci, Giuliano; de la Sierra, Alejandro; Kreutz, Reinhold; Laurent, Stéphane; Manolis, Athanasios J; Tsioufis, Kostantinos

2017-12-01

Despite the improvements in the management of hypertension during the last three decades, it continues to be one of the leading causes of cardiovascular morbidity and mortality worldwide. Effective and sustained reductions in blood pressure (BP) reduce the incidence of myocardial infarction, stroke, congestive heart failure and cardiovascular death. However, the proportion of patients who achieve the recommended BP goal (< 140/90 mmHg) is persistently low, worldwide. Poor adherence to therapy, complex therapeutic regimens, clinical inertia, drug-related adverse events and multiple risk factors or comorbidities contribute to the disparity between the potential and actual BP control rate. Previously we published a practical therapeutic platform for the treatment of hypertension based on clinical evidence, guidelines, best practice and clinical experience. This platform provides a personalised treatment approach and can be used to improve BP control and simplify treatment. It uses long-acting, effective and well-tolerated angiotensin receptor blocker (ARB) olmesartan, in combination with a calcium channel blocker amlodipine, and/or a thiazide diuretic hydrochlorothiazide. These drugs were selected based on the availability in most European Countries of single-pill, fixed formulations in a wide range of doses for both dual- and triple-drug combinations. The platform approach could be applied to other ARBs or angiotensin-converting enzyme inhibitors available in single-pill, fixed-dose combinations. Here, we present an update, which takes into account the results of the recently published studies and extends the applicability of the platform to common conditions that are often neglected or poorly considered in clinical practice guidelines.

Use of diuretics and the risk of gouty arthritis: a systematic review.

PubMed

Hueskes, Berdine A A; Roovers, Elisabeth A; Mantel-Teeuwisse, Aukje K; Janssens, Hein J E M; van de Lisdonk, Eloy H; Janssen, Matthijs

2012-06-01

To systematically review the literature investigating the relationship between use of diuretics and the risk of gouty arthritis. PubMed (1950-October 2009), Embase (1974-October 2009), and the Cochrane Library (up to October 2009) were searched using keywords and MeSH terms diuretics, adverse effects, and gout. For this review, the technique of "best evidence synthesis" was used. Studies reporting frequency, absolute or relative risks, odds ratio, or rate ratio of gouty arthritis in diuretic users compared with nonusers were selected and evaluated. Studies had to be published in English. Checklists from the Dutch Cochrane Centre were used to assess the quality of randomized controlled trials (RCTs), cohort, and case-control studies. Two RCTs, 6 cohort studies, and 5 case-control studies met the inclusion criteria. The overall quality of the studies was moderate. In a RCT the rate ratio of gout for use of bendrofluazide vs placebo was 11.8 (95% CI 5.2-27.0). The other RCT found a rate ratio of 6.3 (95% CI 0.8-51) for use of hydrochlorothiazide plus triamterene vs placebo. Three cohort studies and 4 case-control studies found higher risks of gouty arthritis in users compared with nonusers of diuretics. There is a trend toward a higher risk for acute gouty arthritis attacks in patients on loop and thiazide diuretics, but the magnitude and independence is not consistent. Therefore, stopping these useful drugs in patients who develop gouty arthritis is not supported by the results of this review. Copyright © 2012 Elsevier Inc. All rights reserved.

[Physician knowledge and attitudes on the clinical evaluation and treatment of resistant hypertension: The RESIST study].

PubMed

Coca, A

Resistant hypertension (RH) is associated with a high risk of cardiovascular and renal complications. The purpose of this study was to assess the knowledge and attitudes of Primary Care physicians, general medicine doctors, and clinical cardiologists on the management of this condition. A multicentre, descriptive, observational study based on an ad hoc questionnaire distributed to Primary Care physicians (n=1017) and general medicine physicians/clinical cardiologists (n=457). To establish the diagnosis of resistant hypertension, 69.1% of physicians confirm that systolic/diastolic blood pressure is above 140/90 mmHg, despite treatment. Furthermore, 64.9% only consider this diagnosis if the patient is treated with at least 3 medications, and 50.3% also requires that one of them is a thiazide diuretic (56.7% among specialists, P=.0004). To establish a definite diagnosis of true RH, 89.6% perform 24-h ambulatory blood pressure monitoring (93.3% of specialists, P=.0017), looking specifically for «white-coat» effect in 70.2% of cases. In addition, 79.3% verify that adherence to treatment is adequate. Between 87 and 95% of physicians indicate examinations to exclude causes of secondary hypertension. Up to 54.3% of physicians (71.3% specialists, P<.0001) consider adding a fourth drug and insisting on lifestyle interventions as a priority therapeutic measure. These data show that physician knowledge regarding the management of patients with RH is good. Interestingly, this knowledge is somewhat higher among specialists than among Primary Care physicians. Copyright © 2016 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

Confirmatory testing in primary aldosteronism: extensive medication switching is not needed in all patients

PubMed Central

Solar, Miroslav; Malirova, Eva; Ballon, Marek; Pelouch, Radek; Ceral, Jiri

2012-01-01

Objective Confirmatory testing of suspected primary aldosteronism (PA) requires an extensive medication switch that can be difficult for patients with severe complicated hypertension and/or refractory hypokalemia. For this reason, we investigated the effect of chronic antihypertensive medication on confirmatory testing results. To allow the results to be interpreted, the reproducibility of confirmatory testing was also evaluated. Design and methods The study enrolled 114 individuals with suspected PA who underwent two confirmatory tests. The patients were divided into two groups. In Group A, both tests were performed on the guidelines-recommended therapy, i.e. not interfering with the renin–angiotensin–aldosterone system. In Group B, the first test was performed on chronic therapy with the exclusion of thiazides, loop diuretics, and aldosterone antagonists; and the second test was performed on guidelines-recommended therapy. Saline infusion, preceded by oral sodium loading, was used to suppress aldosterone secretion. Results Agreement in the interpretation of the two confirmatory tests was observed in 84 and 66% of patients in Groups A and B respectively. For all 20 individuals in Group A who ever had end-test serum aldosterone levels ≥240 pmol/l, aldosterone was concordantly nonsuppressible during the other test. Similarly, for all 16 individuals in Group B who had end-test serum aldosterone levels ≥240 pmol/l on modified chronic therapy, aldosterone remained nonsuppressible with guidelines-recommended therapy. Conclusion Confirmatory testing performed while the patient is on chronic therapy without diuretics and aldosterone antagonists can confirm the diagnosis of PA, provided serum aldosterone remains markedly elevated at the end of saline infusion. PMID:22253400

Multi-modal intervention to reduce cardiovascular risk among hypertensive older adults: Design of a randomized clinical trial

PubMed Central

Buford, Thomas W.; Anton, Stephen D.; Bavry, Anthony; Carter, Christy S.; Daniels, Michael J.; Pahor, Marco

2015-01-01

Persons aged over 65 years account for over 75% of healthcare expenditures and deaths attributable to cardiovascular disease (CVD). Accordingly, reducing CVD risk among older adults is an important public health priority. Functional status, determined by measures of physical performance, is an important predictor of cardiovascular outcomes in older adults and declines more rapidly in seniors with hypertension. To date, physical exercise is the primary strategy for attenuating declines in functional status. Yet despite the general benefits of training, exercise alone appears to be insufficient for preventing this decline. Thus, alternative or adjuvant strategies are needed to preserve functional status among seniors with hypertension. Prior data suggest that angiotensin converting enzyme inhibitors (ACEi) may be efficacious in enhancing exercise-derived improvements in functional status yet this hypothesis has not been tested in a randomized controlled trial. The objective of this randomized, double-masked pilot trial is to gather preliminary efficacy and safety data necessary for conducting a full-scale trial to test this hypothesis. Sedentary men and women ≥ 65 years of age with functional limitations and hypertension are being recruited into this 24 week intervention study. Participants are randomly assigned to one of three conditions: (1) ACEi plus exercise training, (2) thiazide diuretic plus exercise training, or (3) AT1 receptor antagonist plus exercise training. The primary outcome is change in walking speed and secondary outcomes consist of other indices of CV risk including exercise capacity, body composition, as well as circulating indices of metabolism, inflammation and oxidative stress. PMID:26115878

Admission plasma glucose and diabetes mellitus in elderly admissions to hospital.

PubMed

Croxson, S C; Keir, S L; Ibbs, L

1997-05-01

Over 6 months, all admissions to three geriatric wards were studied to define an admission plasma glucose level (APG) that identified previously undiagnosed diabetes mellitus. Subjects with APG> or =7.0 mmol l(-1) had a modified oral glucose tolerance test (OGTT) when well before discharge if their dose of steroid and/or thiazide was constant, and they were neither terminally ill nor dead; excluded were 1 subject on reducing steroid doses, and 9 moribund admissions without APG. If the first 2 h OGTT result was > or =11.1 mmol l(-1), a second OGTT was performed 6 weeks later to fulfil 1985 WHO criteria. Subjects with APG<7.0 mmol l(-1) did not have OGTT. Seventy had a previous diagnosis of diabetes; scrutiny of records and OGTT refuted the diagnosis in 5, who were excluded from further analysis. Diabetes was only commonly found among those with APG> or =8.0 mmol l(-1), and the proportion was small until APG> or =13 mmol l(-1), although even then only 47% (95% CI 21-73%) had diabetes. Fourteen of 28 subjects with initial OGTT results suggesting diabetes were not diabetic on retesting. Inpatient mortality was higher if APG> or =7.0 (Odds ratio 2.82; CI 1.63-4.89) or the subject had known diabetes (Odds ratio 2.43; CI 1.15-4.97) compared to APG<7; there was no age or sex difference between these three groups. We conclude that, unless overtly diabetic, diagnosis of diabetes in elderly medical admissions needs later confirmation.

How are patients with heart failure treated in primary care?
.

PubMed

Vaillant-Roussel, Hélène; Pereira, Bruno; Gibot-Boeuf, Sylvaine; Eschalier, Romain; Dubray, Claude; Boussageon, Rémy; Vorilhon, Philippe

2018-05-24

The aim of this study was to assess the adherence of general practitioners (GPs) to guidelines in patients with heart failure with reduced ejection fraction (HFrEF) and to describe GPs' prescribing behavior regarding patients with heart failure with preserved ejection fraction (HFpEF). Cross-sectional study as part of the ETIC trial. Five classes of drugs were described: angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs); β-blockers (BBs); mineralocorticoid receptor antagonists (MRAs); diuretics (thiazide or loop diuretics); and digoxin. 178 patients were studied: their mean age was 73.5 years (± 10.6). Of the 128 patients with HFpEF, 81.3% received ACEIs or ARBs, 63.3% received BBs, 13.3% received MRAs, 75.8% received diuretics, and 12.5% received digoxin. Of the 50 patients with HFrEF, 84% received ACEIs or ARBs, 74% received BBs, 20% received MRAs, 76% received diuretics, and 2% received digoxin. 25% of the patients were given a drug in accordance with the recommendations for drug class but not a drug authorized for the HFrEF indication. Among the patients with HFrEF who were treated in accordance with the recommendations, target doses were achieved in 1/3 given ACEIs/ARBs, 1/4 given BBs, and 1/2 given MRAs. Only 6% of the patients had a perfect Global Adherence Indicator-3 (GAI-3) with all target doses achieved. Several drugs were prescribed even though they were not recommended, and few patients were treated optimally. It seems to be necessary to develop a pragmatic tool to help GPs and cardiologists in optimizing treatment.
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The Art and Science of Using Diuretics in the Treatment of Heart Failure in Diverse Clinical Settings.

PubMed

Islam, Md Shahidul

2018-01-01

It is important to understand the rationale for appropriate use of different diuretics, alone or in combination, in different heart failure patients, under diverse clinical settings. Clinicians and nurses engaged in heart failure care, must be familiar with different diuretics, their appropriate doses, methods of administration, monitoring of the responses, and the side-effects. Inappropriate use of diuretics, both under-treatment and overtreatment, and poor follow-up can lead to failures, and adverse outcomes. Adequate treatment of congestion, with rather aggressive use of diuretics, is necessary, even if that may worsen renal function temporarily in some patients. Diuretic treatment should later be titrated down, by early recognition of the euvolemic sate, which can be assessed by clinical examination, measurement of the natriuretic peptides, and when possible, echocardiographic estimation of the left ventricular filling pressure. You need to treat patients, who are truly resistant to the loop diuretics, by administering the diuretics as intravenous bolus injection followed by continuous infusion, and/or by sequential nephron blockade by adding the thiazide diuretics. You need to use the diuretics based on a sound understanding of the pathophysiology of the disease process, the pharmacokinetics and pharmacodynamics of the diuretics, even when strong evidences for your choices might be lacking. Some patients may benefit from injection of loop diuretics together with hypertonic saline, and others from injection of loop diuretics with albumin. Patient education, and regular follow up of the treatment of heart failure patients, in out-patient settings are important for reducing the rates of complications, and for reducing the needs for urgent hospitalizations.

Plasma Potassium Determines NCC Abundance in Adult Kidney-Specific γENaC Knockout.

PubMed

Boscardin, Emilie; Perrier, Romain; Sergi, Chloé; Maillard, Marc P; Loffing, Johannes; Loffing-Cueni, Dominique; Koesters, Robert; Rossier, Bernard C; Hummler, Edith

2018-03-01

The amiloride-sensitive epithelial sodium channel (ENaC) and the thiazide-sensitive sodium chloride cotransporter (NCC) are key regulators of sodium and potassium and colocalize in the late distal convoluted tubule of the kidney. Loss of the α ENaC subunit leads to a perinatal lethal phenotype characterized by sodium loss and hyperkalemia resembling the human syndrome pseudohypoaldosteronism type 1 (PHA-I). In adulthood, inducible nephron-specific deletion of α ENaC in mice mimics the lethal phenotype observed in neonates, and as in humans, this phenotype is prevented by a high sodium (HNa + )/low potassium (LK + ) rescue diet. Rescue reflects activation of NCC, which is suppressed at baseline by elevated plasma potassium concentration. In this study, we investigated the role of the γ ENaC subunit in the PHA-I phenotype. Nephron-specific γ ENaC knockout mice also presented with salt-wasting syndrome and severe hyperkalemia. Unlike mice lacking α ENaC or β ΕΝaC, an HNa + /LK + diet did not normalize plasma potassium (K + ) concentration or increase NCC activation. However, when K + was eliminated from the diet at the time that γ ENaC was deleted, plasma K + concentration and NCC activity remained normal, and progressive weight loss was prevented. Loss of the late distal convoluted tubule, as well as overall reduced β ENaC subunit expression, may be responsible for the more severe hyperkalemia. We conclude that plasma K + concentration becomes the determining and limiting factor in regulating NCC activity, regardless of Na + balance in γ ENaC-deficient mice. Copyright © 2018 by the American Society of Nephrology.

Redistribution of distal tubule Na+-Cl- cotransporter (NCC) in response to a high-salt diet.

PubMed

Sandberg, Monica B; Maunsbach, Arvid B; McDonough, Alicia A

2006-08-01

The distal convoluted tubule (DCT) apical Na(+)-Cl(-) cotransporter (NCC) is responsible for the reabsorption of 5-10% of filtered NaCl and is the target for thiazide diuretics. NCC abundance is increased during dietary NaCl restriction and by aldosterone and decreased during a high-salt (HS) diet and mineralocorticoid blockade. This study tested the hypothesis that subcellular distribution of NCC is also regulated in response to changes in dietary salt. Six-week-old Sprague-Dawley rats were fed a normal-salt diet (NS; 0.4% NaCl) for 3 wk, then switched to a HS diet (4% NaCl) for 3 wk or a low-salt diet (LS; 0.07% NaCl) for 1 wk. Under anesthesia, kidneys were excised, renal cortex was dissected, and NCC was analyzed with specific antibodies after either 1) density gradient centrifugation followed by immunoblotting or 2) fixation followed by immunoelectron microscopy. The HS diet decreased NCC abundance to 0.50 +/- 0.10 of levels in LS diet (1.00 +/- 0.23). The HS diet also caused a redistribution of NCC from low to higher density membranes. Immunoelectron microscopy revealed that NCC resides predominantly in the apical membrane in rats fed the LS diet and increases in subapical vesicles in rats fed the HS diet. In conclusion, a HS diet provokes a rapid and persistent redistribution of NCC from apical to subapical membranes, a mechanism that would facilitate a homeostatic decrease in NaCl reabsorption in the DCT to compensate for increased dietary salt.

Acute inhibition of NCC does not activate distal electrogenic Na+ reabsorption or kaliuresis.

PubMed

Hunter, Robert W; Craigie, Eilidh; Homer, Natalie Z M; Mullins, John J; Bailey, Matthew A

2014-02-15

Na(+) reabsorption from the distal renal tubule involves electroneutral and electrogenic pathways, with the latter promoting K(+) excretion. The relative activities of these two pathways are tightly controlled, participating in the minute-to-minute regulation of systemic K(+) balance. The pathways are interdependent: the activity of the NaCl cotransporter (NCC) in the distal convoluted tubule influences the activity of the epithelial Na(+) channel (ENaC) downstream. This effect might be mediated by changes in distal Na(+) delivery per se or by molecular and structural adaptations in the connecting tubule and collecting ducts. We hypothesized that acute inhibition of NCC activity would cause an immediate increase in Na(+) flux through ENaC, with a concomitant increase in renal K(+) excretion. We tested this using renal clearance methodology in anesthetized mice, by the administration of hydrochlorothiazide (HCTZ) and/or benzamil (BZM) to exert specific blockade of NCC and ENaC, respectively. Bolus HCTZ elicited a natriuresis that was sustained for up to 110 min; urinary K(+) excretion was not affected. Furthermore, the magnitude of the natriuresis was no greater during concomitant BZM administration. This suggests that ENaC-mediated Na(+) reabsorption was not normally limited by Na(+) delivery, accounting for the absence of thiazide-induced kaliuresis. After dietary Na(+) restriction, HCTZ elicited a kaliuresis, but the natiuretic effect of HCTZ was not enhanced by BZM. Our findings support a model in which inhibition of NCC activity does not increase Na(+) reabsorption through ENaC solely by increasing distal Na(+) delivery but rather by inducing a molecular and structural adaptation in downstream nephron segments.

Hypocalcemia

PubMed Central

Fong, Jeremy; Khan, Aliya

2012-01-01

Abstract Objective To provide family physicians with an evidence-based approach to the diagnosis and management of hypocalcemia. Quality of evidence MEDLINE and EMBASE articles from 2000 to 2010 were searched, with a focus on the diagnosis and management of hypocalcemia. Levels of evidence (I to III) were cited where appropriate, with most studies providing level II or III evidence. References of pertinent papers were also searched for relevant articles. Main message Chronic hypocalcemia is commonly due to inadequate levels of parathyroid hormone or vitamin D, or due to resistance to these hormones. Treatment focuses on oral calcium and vitamin D supplements, as well as magnesium if deficiency is present. Treatment can be further intensified with thiazide diuretics, phosphate binders, and a low-salt and low-phosphorus diet when treating hypocalcemia secondary to hypoparathyroidism. Acute and life-threatening calcium deficit requires treatment with intravenous calcium. The current treatment recommendations are largely based on expert clinical opinion and published case reports, as adequately controlled clinical trial data are not currently available. Complications of current therapies for hypoparathyroidism include hypercalciuria, nephrocalcinosis, renal impairment, and soft tissue calcification. Current therapy is limited by serum calcium fluctuations. Although these complications are well recognized, the effects of therapy on overall well-being, mood, cognition, and quality of life, as well as the risk of complications, have not been adequately studied. Conclusion Family physicians play a crucial role in educating patients about the long-term management and complications of hypocalcemia. Currently, management is suboptimal and marked by fluctuations in serum calcium and a lack of approved parathyroid hormone replacement therapy for hypoparathyroidism. PMID:22439169

Association of primary hyperparathyroidism and humoral hypercalcemia of malignancy in a patient with clear cell renal carcinoma.

PubMed

Gomes, Letícia da Silva; Kulak, Carolina A M; Costa, Tatiana Munhoz da Rocha Lemos; Vasconcelos, Evandro Cezar Guerreiro; Carvalho, Maurício de; Borba, Victoria Zeghbi Cochenski

2015-02-01

Hypercalcemia is found frequently in patients with cancer. Besides the etiology related to the malignancy, other causes should be considered in the differential diagnostic, as primary hyperparathyroidism, granulomatous diseases and the use of thiazide diuretics. We present a case report of a severe hypercalcemia due to a rare association and review the relevant literature. A female patient, 57 years old, sent to the Endocrinology Service of Hospital das Clínicas da Universidade do Paraná (SEMPR) in order to investigate severe hypercalcemia with frequent need of hospitalization. The patient was in chemotherapy treatment for recurrence of clear cell renal cancer. During the investigation she presented high level of parathyroid hormone (PTH) and parathyroid scintigraphy suggestive of hyperplasia/ adenoma of parathyroid, histopathological diagnosis was confirmed after parathyroidectomy. After surgery the patient presented undetectable levels of PTH. However, she continued with progressive increase of serum calcium, with no signs of bone metastases or change in vitamin D metabolism. The investigation showed high levels of PTH-related protein (PTHrP), leading us to the diagnosis of hypercalcemia of malignancy. The patient presented severe hypercalcemia due to the rare association of primary hyperparathyroidism and humoral hypercalcemia of malignancy due to secretion of PTHrP by tumor cells. The presence of isolated primary hyperparathyroidism, as a cause of hypercalcemia in cancer patients, has been described in approximately 5-10% of the patients. However, the association of primary hyperparathyroidism and humoral hypercalcemia of malignancy (which means with concomitant elevation of PTH and PTHrP) is rare, only three cases have been described in the literature.

Is the renal kallikrein-kinin system a factor that modulates calciuria?

PubMed

Negri, Armando Luis

Renal tubular calcium reabsorption is one of the principal factors that determine serum calcium concentration and calcium excretion. Calcium excretion is regulated by the distal convoluted tubule and connecting tubule, where the epithelial calcium channel TRPV5 can be found, which limits the rate of transcellular calcium transport. The dynamic presence of the TRPV5 channel on the surface of the tubular cell is mediated by an endosomal recycling process. Different intrarenal factors are involved in calcium channel fixation in the apical membrane, including the anti-ageing hormone klotho and tissue kallikrein (TK). Both proteins are synthesised in the distal tubule and secreted in the tubular fluid. TK stimulates active calcium reabsorption through the bradykinin receptor B2 that compromises TRPV5 activation through the protein kinase C pathway. TK-deficient mice show hypercalciuria of renal origin comparable to that seen in TRPV5 knockout mice. There is a polymorphism with loss of function of the human TK gene R53H (allele H) that causes a marked decrease in enzymatic activity. The presence of the allele H seems to be common at least in the Japanese population (24%). These individuals have a tendency to greater calcium and sodium excretion in urine that is more evident during furosemide infusion. Future studies should analyse if manipulating the renal kallikrein-kinin system can correct idiopathic hypercalciuria with drugs other than thiazide diuretics. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

Carbonic anhydrase inhibitors. Comparison of chlorthalidone, indapamide, trichloromethiazide, and furosemide X-ray crystal structures in adducts with isozyme II, when several water molecules make the difference.

PubMed

Temperini, Claudia; Cecchi, Alessandro; Scozzafava, Andrea; Supuran, Claudiu T

2009-02-01

Thiazide and high ceiling diuretics were recently shown to inhibit all mammalian isoforms of carbonic anhydrase (CA, EC 4.2.1.1) with a very different profile as compared to classical inhibitors, such as acetazolamide, methazolamide, and ethoxzolamide. Some of these structurally related compounds have a very different behavior against the widespread isozyme CA II, with chlorthalidone, trichloromethiazide, and furosemide being efficient inhibitors against CA II (K(I)s of 65-138 nM), whereas indapamide is a much weaker one (K(I) of 2520 nM). Furthermore, some of these diuretics are quite efficient (low nanomolar) inhibitors of other isoforms, for example, chlorthalidone against hCA VB, VII, IX, and XIII; indapamide against CA VII, IX, XII, and XIII, trichloromethiazide against CA VII and IX, and furosemide against CA I and XIV. Examining the four X-ray crystal structures of their CA II adducts, we observed several (2-3) active site water molecules interacting with the chlorthalidone, trichloromethiazide, and furosemide scaffolds which may be responsible for this important difference of activity. Indeed, indapamide bound to CA II has no interactions with active site water molecules. Chlorthalidone bound within the CA II active site is in an enolic (lactimic) tautomeric form, with the enolic OH also participating in two strong hydrogen bonds with Asn67 and a water molecule. The newly evidenced binding modes of these diuretics may be exploited for designing better CA II inhibitors as well as compounds with selectivity/affinity for various isoforms with medicinal chemistry applications.

Drug-vitamin D interactions: A systematic review of the literature

PubMed Central

Oppeneer, Sarah J.; Kelly, Julia A.; Hamilton-Reeves, Jill M.

2017-01-01

Extensive media coverage of the potential health benefits of vitamin D supplementation has translated into substantial increases in supplement sales over recent years. Yet, the potential for drug-vitamin D interactions is rarely considered. This systematic review of the literature was conducted to evaluate the extent to which drugs affect vitamin D status or supplementation alters drug effectiveness or toxicity in humans. Electronic databases were used to identify eligible peer-reviewed studies published through September 1, 2010. Study characteristics and findings were abstracted, and quality was assessed for each study. A total of 109 unique reports met the inclusion criteria. The majority of eligible studies were classified as Class C (non-randomized trials, case-control studies, or time series) or D (cross-sectional, trend, case report/series, or before-and-after studies). Only two Class C and three Class D studies were of positive quality. Insufficient evidence was available to determine whether lipase inhibitors, antimicrobial agents, antiepileptic drugs, highly active antiretroviral agents or H2 receptor antagonists alter serum 25(OH)D concentrations. Atorvastatin appears to increase 25(OH)D concentrations, while concurrent vitamin D supplementation decreases concentrations of atorvastatin. Use of thiazide diuretics in combination with calcium and vitamin D supplements may cause hypercalcemia in the elderly, or those with compromised renal function or hyperparathyroidism. Larger studies with stronger study designs are needed to clarify potential drug-vitamin D interactions, especially for drugs metabolized by cytochrome P450 3A4 (CYP3A4). Health care providers should be aware of the potential for drug-vitamin D interactions. PMID:23307906

Azilsartan medoxomil/chlorthalidone: a new fixed-dose combination antihypertensive.

PubMed

Pierini, Danielle; Anderson, Katherine Vogel

2013-05-01

To evaluate the efficacy, safety, and clinical utility of the combination product azilsartan medoxomil/chlorthalidone for the treatment of hypertension. Articles indexed in PubMed through December 2012 were identified using the MeSH terms azilsartan and chlorthalidone, Edarbyclor, TAK-490, and Edarbi. Additional information was gathered from references cited in the identified publications, the package insert, and from a review of the ClinicalTrials.gov registry. English-language articles, including clinical trials and reviews involving azilsartan medoxomil/chlorthalidone or each component individually for the treatment of hypertension were reviewed. The antihypertensive combination tablet azilsartan medoxomil/chlorthalidone is the first to combine an inhibitor of the renin-angiotensin-aldosterone system with chlorthalidone, a thiazide-type diuretic. In 4 randomized controlled trials (3 published to date), azilsartan medoxomil/chlorthalidone 40 mg/12.5 mg and 40 mg/25 mg reduced blood pressure (BP) significantly more than comparators did, including an approximately 5-mm Hg greater BP reduction than olmesartan medoxomil/hydrochlorothiazide 40 mg/25 mg and azilsartan medoxomil/hydrochlorothiazide. Reductions in 24-hour ambulatory BP and clinic BP were observed, and a greater proportion of patients achieved BP targets while receiving azilsartan medoxomil/chlorthalidone. Azilsartan medoxomil/chlorthalidone was generally well tolerated, with minor, transient increases in serum creatinine and without a significant effect on potassium homeostasis. No studies have directly examined cardiovascular morbidity and mortality benefits associated with this combination. The combination of azilsartan medoxomil/chlorthalidone has demonstrated safety and efficacy in lowering BP in hypertensive patients to a greater degree than olmesartan medoxomil/hydrochlorothiazide and azilsartan medoxomil/hydrochlorothiazide. As a fixed-dose combination tablet, it offers several clinical advantages.

Ion transport its regulation in the endolymphatic sac: suggestions for clinical aspects of Meniere's disease.

PubMed

Mori, Nozomu; Miyashita, Takenori; Inamoto, Ryuhei; Matsubara, Ai; Mori, Terushige; Akiyama, Kosuke; Hoshikawa, Hiroshi

2017-04-01

Ion transport and its regulation in the endolymphatic sac (ES) are reviewed on the basis of recent lines of evidence. The morphological and physiological findings demonstrate that epithelial cells in the intermediate portion of the ES are more functional in ion transport than those in the other portions. Several ion channels, ion transporters, ion exchangers, and so on have been reported to be present in epithelial cells of ES intermediate portion. An imaging study has shown that mitochondria-rich cells in the ES intermediate portion have a higher activity of Na + , K + -ATPase and a higher Na + permeability than other type of cells, implying that molecules related to Na + transport, such as epithelial sodium channel (ENaC), Na + -K + -2Cl - cotransporter 2 (NKCC2) and thiazide-sensitive Na + -Cl - cotransporter (NCC), may be present in mitochondria-rich cells. Accumulated lines of evidence suggests that Na + transport is most important in the ES, and that mitochondria-rich cells play crucial roles in Na + transport in the ES. Several lines of evidence support the hypothesis that aldosterone may regulate Na + transport in ES, resulting in endolymph volume regulation. The presence of molecules related to acid/base transport, such as H + -ATPase, Na + -H + exchanger (NHE), pendrin (SLC26A4), Cl - -HCO 3 - exchanger (SLC4A2), and carbonic anhydrase in ES epithelial cells, suggests that acid/base transport is another important one in the ES. Recent basic and clinical studies suggest that aldosterone may be involved in the effect of salt-reduced diet treatment in Meniere's disease.

Demographic, dietary, and urinary factors and 24-h urinary calcium excretion.

PubMed

Taylor, Eric N; Curhan, Gary C

2009-12-01

Higher urinary calcium is a risk factor for nephrolithiasis. This study delineated associations between demographic, dietary, and urinary factors and 24-h urinary calcium. Cross-sectional studies were conducted of 2201 stone formers (SF) and 1167 nonstone formers (NSF) in the Health Professionals Follow-up Study (men) and Nurses' Health Studies I and II (older and younger women). Median urinary calcium was 182 mg/d in men, 182 mg/d in older women, and 192 mg/d in younger women. Compared with NSF, urinary calcium as a fraction of calcium intake was 33 to 38% higher in SF (P values < or =0.01). In regression analyses, participants were combined because associations with urinary calcium were similar in each cohort and in SF and NSF. After multivariate adjustment, participants in the highest quartile of calcium intake excreted 18 mg/d more urinary calcium than those in the lowest (P trend =0.01). Caffeine and family history of nephrolithiasis were positively associated, whereas urinary potassium, thiazides, gout, and age were inversely associated, with urinary calcium. After multivariate adjustment, participants in the highest quartiles of urinary magnesium, sodium, sulfate, citrate, phosphorus, and volume excreted 71 mg/d, 37 mg/d, 44 mg/d, 61 mg/d, 37 mg/d, and 24 mg/d more urinary calcium, respectively, than participants in the lowest (P values trend < or =0.01). Intestinal calcium absorption and/or negative calcium balance is greater in SF than NSF. Higher calcium intakes at levels typically observed in free-living individuals are associated with only small increases in urinary calcium.

Hypertension and cardiac arrhythmias: executive summary of a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

PubMed

Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S; Steffel, Jan; Marín, Francisco; de Oliveira Figueiredo, Márcio Jansen; de Simone, Giovanni; Tzou, Wendy S; En Chiang, Chern; Williams, Bryan

2017-10-01

Hypertension (HTN) is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease (CAD), stroke, peripheral artery disease and chronic renal failure. Hypertensive heart disease can manifest as many types of cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in HTN patients, especially in those with left ventricular hypertrophy (LVH), CAD, or HF. In addition, high doses of thiazide diuretics commonly used to treat HTN, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesaemia), contributing further to arrhythmias, while effective blood pressure control may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between HTN and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit of comprehensively reviewing the available evidence and publishing a joint consensus document on HTN and cardiac arrhythmias, and providing up-to-date consensus recommendations for use in clinical practice. The ultimate judgment on the care of a specific patient must be made by the healthcare provider and the patient in light of all individual factors presented. This is an executive summary of the full document co-published by EHRA in EP-Europace. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

Performance assessment through pre- and post-training evaluation of continuing medical education courses in prevention and management of cardio-vascular diseases in primary health care facilities of Armenia.

PubMed

Khachatryan, Lilit; Balalian, Arin

2013-12-01

To assess the difference of pre- and post-training performance evaluation of continuing medical education (CME) courses in cardio-vascular diseases (CVD) management among physicians at primary health care facilities of Armenian regions we conducted an evaluation survey. 212 medical records were surveyed on assessment of performance before and after the training courses through a self-employed structured questionnaire. Analysis of survey revealed statistically significant differences (p < 0.05) in a number of variables: threefold increased recording of lipids and body mass index (p = 0.001); moderate increased recording of comorbidities and aspirin prescription (p < 0.012); eightfold increased recording of dyslipidemia management plan, twofold increased recording for CVD management plan and fivefold increased recording for CVD absolute risk (p = 0.000). Missing records of electrocardiography and urine/creatinine analyses decreased statistically significantly (p < 0.05). Statistically significant decrease was observed in prescription of thiazides and angiotensin receptor blockers/angiotensin converting enzyme inhibitors (p < 0.005), while prescription of statins and statins with diet for dyslipidemia management showed increased recording (p < 0.05). Similarly, we observed increased records for counseling of rehabilitation physical activity (p = 0.006). In this survey most differences in pre- and post-evaluation of performance assessment may be explained by improved and interactive training modes, more advanced methods of demonstration of modeling. Current findings may serve a basis for future planning of CME courses for physicians of remote areas facing challenges in upgrading their knowledge, as well as expand the experience of performance assessment along with evaluation of knowledge scores.

Hypertension and cardiac arrhythmias: a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE).

PubMed

Lip, Gregory Y H; Coca, Antonio; Kahan, Thomas; Boriani, Giuseppe; Manolis, Antonis S; Olsen, Michael Hecht; Oto, Ali; Potpara, Tatjana S; Steffel, Jan; Marín, Francisco; de Oliveira Figueiredo, Márcio Jansen; de Simone, Giovanni; Tzou, Wendy S; Chiang, Chern-En; Williams, Bryan; Dan, Gheorghe-Andrei; Gorenek, Bulent; Fauchier, Laurent; Savelieva, Irina; Hatala, Robert; van Gelder, Isabelle; Brguljan-Hitij, Jana; Erdine, Serap; Lovic, Dragan; Kim, Young-Hoon; Salinas-Arce, Jorge; Field, Michael

2017-06-01

Hypertension is a common cardiovascular risk factor leading to heart failure (HF), coronary artery disease, stroke, peripheral artery disease and chronic renal insufficiency. Hypertensive heart disease can manifest as many cardiac arrhythmias, most commonly being atrial fibrillation (AF). Both supraventricular and ventricular arrhythmias may occur in hypertensive patients, especially in those with left ventricular hypertrophy (LVH) or HF. Also, some of the antihypertensive drugs commonly used to reduce blood pressure, such as thiazide diuretics, may result in electrolyte abnormalities (e.g. hypokalaemia, hypomagnesemia), further contributing to arrhythmias, whereas effective control of blood pressure may prevent the development of the arrhythmias such as AF. In recognizing this close relationship between hypertension and arrhythmias, the European Heart Rhythm Association (EHRA) and the European Society of Cardiology (ESC) Council on Hypertension convened a Task Force, with representation from the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS), and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE), with the remit to comprehensively review the available evidence to publish a joint consensus document on hypertension and cardiac arrhythmias, and to provide up-to-date consensus recommendations for use in clinical practice. The ultimate judgment regarding care of a particular patient must be made by the healthcare provider and the patient in light of all of the circumstances presented by that patient. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Bone Mineral Density Changes Among Women Initiating Blood Pressure Lowering Drugs: A SWAN Cohort Study

PubMed Central

Solomon, Daniel H.; Ruppert, Kristine; Zhao, Zhenping; Lian, YinJuan; Kuo, I-Hsin; Greendale, Gail A.; Finkelstein, Joel S.

2016-01-01

Purpose Several blood pressure lowering drugs may affect bone mineral density (BMD), leading to altered fracture risk. We examined the effect of blood pressure lowering drugs on BMD using data from the Study of Women’s Health Across the Nation. Methods We conducted a propensity score matched cohort study. Women were initiators of ACE inhibitors (ACEi), beta-blockers (BB), or thiazide diuretics (THZD). Their annualized BMD changes during the 14-years of observation were compared with non-users. Results Among the 2312 eligible women, we found 69 ACEi, 71 BB, and 74 THZD users who were matched by a propensity score with the same number of non-users. THZD users had a slower annual percent decline in BMD compared to nonusers at the femoral neck (FN) (−0.28% vs −0.88%; p = 0.008) and the spine (−0.74% vs −1.0%; p = 0.34), albeit not statistically significant. Annual percent changes in BMD among ACEi and BB users were similar to rates in non-users. In comparison with BB, THZD use was associated with a trend toward less annualized BMD loss at the spine (−0.35% vs −0.60%; p = 0.08) and a similar trend at the FN (−0.39% vs −0.64%; p = 0.08); in comparisons with ACEi, THZD was also associated with less loss at the FN (−0.48% vs −0.82%; p = 0.02), but not at the spine (−0.40% vs −0.56%; p = 0.23). Conclusions Neither ACEi nor BB were associated with improvements in BMD. THZD use was associated with less annualized loss of BMD compared with non-users, as well as compared with ACEi and BB. PMID:26449354

Effect of diuretics on renal tubular transport of calcium and magnesium.

PubMed

Alexander, R Todd; Dimke, Henrik

2017-06-01

Calcium (Ca 2+ ) and Magnesium (Mg 2+ ) reabsorption along the renal tubule is dependent on distinct trans- and paracellular pathways. Our understanding of the molecular machinery involved is increasing. Ca 2+ and Mg 2+ reclamation in kidney is dependent on a diverse array of proteins, which are important for both forming divalent cation-permeable pores and channels, but also for generating the necessary driving forces for Ca 2+ and Mg 2+ transport. Alterations in these molecular constituents can have profound effects on tubular Ca 2+ and Mg 2+ handling. Diuretics are used to treat a large range of clinical conditions, but most commonly for the management of blood pressure and fluid balance. The pharmacological targets of diuretics generally directly facilitate sodium (Na + ) transport, but also indirectly affect renal Ca 2+ and Mg 2+ handling, i.e., by establishing a prerequisite electrochemical gradient. It is therefore not surprising that substantial alterations in divalent cation handling can be observed following diuretic treatment. The effects of diuretics on renal Ca 2+ and Mg 2+ handling are reviewed in the context of the present understanding of basal molecular mechanisms of Ca 2+ and Mg 2+ transport. Acetazolamide, osmotic diuretics, Na + /H + exchanger (NHE3) inhibitors, and antidiabetic Na + /glucose cotransporter type 2 (SGLT) blocking compounds, target the proximal tubule, where paracellular Ca 2+ transport predominates. Loop diuretics and renal outer medullary K + (ROMK) inhibitors block thick ascending limb transport, a segment with significant paracellular Ca 2+ and Mg 2+ transport. Thiazides target the distal convoluted tubule; however, their effect on divalent cation transport is not limited to that segment. Finally, potassium-sparing diuretics, which inhibit electrogenic Na + transport at distal sites, can also affect divalent cation transport. Copyright © 2017 the American Physiological Society.

Efficacy and safety of tolvaptan in heart failure patients with sustained volume overload despite the use of conventional diuretics: a phase III open-label study.

PubMed

Fukunami, Masatake; Matsuzaki, Masunori; Hori, Masatsugu; Izumi, Tohru

2011-12-01

Volume overload is a common complication associated with heart failure (HF) and is recommended to be treated with loop or thiazide diuretics. However, use of diuretics can cause serum electrolyte imbalances and diuretic resistance. Tolvaptan, a selective, oral, non-peptide vasopressin V2-receptor antagonist, offers a new option for treating volume overload in HF patients. The aim of this study was to investigate the efficacy and safety of tolvaptan in Japanese HF patients with volume overload. Fifty-one HF patients with volume overload, despite using conventional diuretics, were treated with 15 mg/day tolvaptan for 7 days. If the response was insufficient at Day 7, tolvaptan was continued for a further 7 days at either 15 mg/day or 30 mg/day. Outcomes included changes in body weight, symptoms and safety parameters. Thirty-six patients discontinued treatment within 7 days, therefore 15 patients entered the second phase of treatment. In two patients, tolvaptan was increased to 30 mg/day after 7 days. Body weight was reduced on Day 7 (-1.95 ± 1.98 kg; n = 41) and Day 14 (-2.35 ± 1.44 kg; n = 11, 15 mg/day). Symptoms of volume overload, including lower limb edema, pulmonary congestion, jugular venous distention and hepatomegaly, were improved by tolvaptan treatment for 7 or 14 days. Neither tolvaptan increased the incidence of severe or serious adverse events when administered for 7-14 days. This study confirms the efficacy and safety of 15 mg/day tolvaptan for 7-14 days in Japanese HF patients with volume overload despite conventional diuretics.

Reappraisal of the diuretic effect of empagliflozin in the EMPA-REG OUTCOME trial: Comparison with classic diuretics.

PubMed

Scheen, A J

2016-09-01

Empagliflozin, a sodium-glucose cotransporter type 2 (SGLT2) inhibitor, has been associated with a remarkable reduction in cardiovascular and all-cause mortality in patients with type 2 diabetes and antecedents of cardiovascular disease. This effect was attributed to a diuretic (haemodynamic) rather than metabolic (antiatherogenic) effect. The aim of this review is to offer arguments that either support or challenge this 'diuretic hypothesis'. The literature was scrutinized to: (1) examine the diuretic effects of SGLT2 inhibitors vs. hydrochlorothiazide as the reference diuretic; (2) analyze the effects of classic diuretics on cardiovascular outcomes and mortality in diabetic patients; and (3) reconsider some of the specific analyses of the EMPA-REG OUTCOME trial possibly related to a diuretic effect. The diuretic effect of empagliflozin has so far been poorly investigated, although SGLT2 inhibitors have actions distinct from those of classic diuretics. The effects of thiazide-like diuretics on cardiovascular and overall mortality have been limited in diabetic patients with hypertension, whereas the effects of mineralocorticoid receptor antagonists in subgroups of diabetic patients with heart failure were more impressive, but still largely inferior to those reported in EMPA-REG, where relative reductions in mortality with empagliflozin were observed in diabetic patients with or without heart failure, arterial hypertension, renal impairment or diuretic background therapy. Although the diuretic hypothesis was put forward to explain the remarkable reduction in mortality with empagliflozin in EMPA-REG, the available results do not support a major contribution of this mechanism, unless the specific diuretic effect of SGLT2 inhibitors turns out to be markedly different from those of classic diuretics. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Effectiveness of preventative and other surgical measures on hypocalcemia following bilateral thyroid surgery: a systematic review and meta-analysis.

PubMed

Antakia, Ramez; Edafe, Ovie; Uttley, Lesley; Balasubramanian, Saba P

2015-01-01

A variety of measures have been proposed to reduce the incidence of post-thyroidectomy hypocalcemia. The aim of this study was to perform a systematic review and meta-analysis of preventive and other surgical measures on post-thyroidectomy hypocalcemia as reported in the literature. Comprehensive searches of the PubMed, EMBASE, and Cochrane databases were performed, and the quality of included papers was assessed using the Cochrane risk of bias tool or a modified Newcastle-Ottawa Scale (NOS). The results of all included studies were summarized, and meta-analyses were performed where appropriate. Thirty-nine randomized controlled trials (RCTs) and 37 observational studies were included. Measures studied included hemostatic techniques, extent of thyroidectomy and central neck dissection, surgical approach, calcium/vitamin D/thiazide diuretic supplements, parathyroid gland autotransplantation (PGAT) and intraoperative parathyroid gland (PG) identification, truncal ligation of inferior thyroid artery (ITA), preoperative magnesium infusion, and use of magnification loupes and Surgicel. Measures associated with significantly lower rates of transient hypocalcemia in meta-analysis were postoperative calcium and vitamin D supplementation compared to either calcium supplements alone (odds ratio (OR) 0.66; p=0.04) or no supplements (OR 0.34; p=0.007), and bilateral subtotal thyroidectomy (BST) compared to Hartley Dunhill (HD) procedure (OR 0.35; p=0.01). Meta-analyses did not demonstrate any measure to be significantly associated with a reduction in permanent hypocalcemia. This review identified postoperative calcium and vitamin D supplementation and bilateral subtotal thyroidectomy (over HD) as being effective in prevention of transient hypocalcemia. However, the majority of RCTs were of low quality, primarily due to a lack of blinding. The wide variability in study design, definitions of hypocalcemia, and methods of assessment prevented meaningful summation of results for permanent hypocalcemia.

Management of male osteoporosis.

PubMed

Cortet, B; Vasseur, J; Grardel, B; Catanzariti, L; Marchandise, X; Delcambre, B

2001-05-01

The objective of this study was to evaluate the efficacy of treatments for male osteoporosis selected based on the cause of the disease. Sixty-three men with osteoporosis (T-score at the lumbar spine and/or femoral neck lower than -2.5) with a mean age of 53+/-11 years were studied. Forty-three (68.3%) had a history of fracturing without trauma (vertebral fractures, 37 patients, 57%). Treatments were as follows: idiopathic osteoporosis: calcium and vitamin D supplements (N = 10) or cyclical etidronate for 2 weeks followed by calcium and vitamin D supplements for 76 days (N = 29); moderate idiopathic phosphate diabetes: calcitriol and phosphate (N = 15); idiopathic hypercalciuria: hydrochlorothiazide (N = 6); and hypogonadism: testosterone (N = 3). Percentage change in bone mineral density (mean +/- standard error of the mean) after 18 months: calcium and vitamin D (lumbar spine: 0.6+/-2; femoral neck: 2.2+/-2.2); etidronate (lumbar spine: 3.6+/-1.4*; femoral neck: 0.5+/-1); calcitriol (lumbar spine: 7.0+/-3.5*; femoral neck: 0.0+/-1.4); thiazide diuretic (lumbar spine: 1+/-3.2; femoral neck: -2.3+/-3.7); and testosterone (lumbar spine: 6.8+/-6.4; femoral neck: 2.5+/-2.7), where *P < 0.05 versus baseline. Gastrointestinal side effects occurred in three patients (4.8%), including two on calcitriol-phosphate therapy and one on etidronate therapy. Of the six (9.5%) patients who experienced incident fractures, four were on etidronate, one on calcitriol-phosphate, and one on calcium-vitamin D. No patients discontinued their treatment because of side effects. Etidronate and the combination of calcitriol-phosphate produce a significant increase in lumbar spine bone mass in men with idiopathic osteoporosis or moderate idiopathic phosphate diabetes.

Bartter syndrome type 3 in an elderly complicated with adrenocorticotropin-deficiency.

PubMed

Tamagawa, Eri; Inaba, Hidefumi; Ota, Takayuki; Ariyasu, Hiroyuki; Kawashima, Hiromichi; Wakasaki, Hisao; Furuta, Hiroto; Nishi, Masahiro; Nakao, Taisei; Kaito, Hiroshi; Iijima, Kazumoto; Nakanishi, Koichi; Yoshikawa, Norishige; Akamizu, Takashi

2014-01-01

Bartter syndrome (BS) is a disorder with normotensive hypokalemic alkalosis and hyperreninemic hyperaldosteronemia. BS affects infants or early childhood. Patients with BS type 3 harbor mutation in CLCNKB, Cl channel Kb. Gitelman syndrome (GS) is a disorder in childhood, with mutation in SLC12A3. Isolated adrenocorticotropin deficiency (IAD) causes secondary adrenal insufficiency. Neither elderly cases, nor cases with IAD were previously reported in BS. A 72-year-old man was admitted with acute adrenal crisis. He had been treated for IAD for 19 years. He had no trouble during perinatal period, delivery, and growth. After the recovery from adrenal crisis, laboratory tests revealed hypokalemia; 3.0 mEq/L (normal: 3.5-4.5), impaired renal function: eGFR; 37.6 mL/min/1.73 m2, normomagnesemia; 2.1 mg/dL (1.7-2.3), hyperreninemia; 59.4 ng/mL/h (0.2-2.7), hyperaldosteronemia; 23.5 ng/dL (3.0-15.9), and normal urinary ratio of calcium/creatinine. In diuretic tests, he showed a fine response to furosemide, and a mild response to thiazide. In genetic tests, no mutation of SLC12A3 was found and homozygous mutation: c.1830 G > A in CLCNKB was shown. Thus he was diagnosed as BS type 3. Current case presented with unusual features as BS type 3, 1) his late and mild clinical manifestation suggested GS rather than BS, 2) laboratory data and diuretics tests did not show typical features as BS, and 3) IAD and chronic renal failure altered electrolyte metabolism. In conclusion, current case implies that BS type 3 should be considered even in elderly cases with normotensive hypokalemia, and highlights importance of endocrinological and genetic examinations.

Hypokalemic paralysis in a middle-aged female with classic Bartter syndrome.

PubMed

Chiang, Wen-Fang; Lin, Shih-Hung; Chan, Jenq-Shyong; Lin, Shih-Hua

2014-02-01

Inherited classic Bartter syndrome (cBS) is an autosomal recessive renal tubular disorder resulting from inactivating mutations in the asolateral chloride channel (C1C-Kb) and usually presents in early infancy or childhood with mild to moderate hypokalemia. Profound hypokalemic paralysis in patients with cBS is extremely rare, especially in middle age. A 45-year-old Chinese female patient was referred for evaluation of chronic severe hypokalemia despite regular K+ supplementation (1 mmol/kg/d). She had had two episodes of muscle paralysis due to severe hypokalemia (K+ 1.9 - 2.1 mmol/l) in the past 3 years. She denied vomiting, diarrhea, or the use of laxatives or diuretics. Her blood pressure was normal. Biochemical studies showed hypokalemia (K+ 2.5 mmol/l) with renal potassium wasting, metabolic alkalosis (HCO3- 32 mmol/l), normomagnesemia (Mg2+ 0.8 mmol/l), hypercalciuria (calcium to creatinine ratio 0.5 mmol/mmol; normal < 0.22 mmol/mol), high plasma renin activity, but normal plasma aldosterone concentration. Abdominal sonography revealed neither renal stones nor nephrocalcinosis. Acquired causes of cBS such as autoimmune disease and drugs were all excluded. Molecular analysis of the CLCNKB gene, encoding ClC-Kb, and SLC12A3, encoding the thiazide-sensitive sodium chloride cotransporter (NCC), revealed compound heterozygous mutations in CLCNKB (L335P and G470E) inherited from her parents; her SLC12A3 was normal. These two mutations were not identified in 100 healthy subjects. Her plasma K+ concentration rose to 3 - 3.5 mmol/l after the addition of spironolactone. Inherited cBS may present with hypokalemic paralysis and should be considered in adult patients with hypokalemia and metabolic alkalosis.

Probing the Allosteric Modulator Binding Site of GluR2 with Thiazide Derivatives

PubMed Central

Ptak, Christopher P.; Ahmed, Ahmed H.; Oswald, Robert E.

2009-01-01

Ionotropic glutamate receptors mediate the majority of vertebrate excitatory synaptic transmission and are therapeutic targets for cognitive enhancement and treatment of schizophrenia. The binding domains of these tetrameric receptors consist of two dimers, and the dissociation of the dimer interface of the ligand-binding domain leads to desensitization in the continued presence of agonist. Positive allosteric modulators act by strengthening the dimer interface and reducing desensitization, thereby increasing steady-state activation. Removing the desensitized state for simplified analysis of receptor activation is commonly achieved using cyclothiazide (CTZ), the most potent modulator of the benzothiadiazide class, with the flip form of the AMPA receptor subtype. IDRA-21, the first benzothiadiazide to have an effect in behavioral tests, is an important lead compound in clinical trials for cognitive enhancement as it can cross the blood-brain barrier. Intermediate structures between CTZ and IDRA-21 show reduced potency suggesting that these two compounds have different contact points associated with binding. To understand how benzothiadiazides bind to the pocket bridging the dimer interface, we generated a series of crystal structures of the GluR2 ligand-binding domain complexed with benzothiadiazide derivatives (IDRA-21, hydroflumethiazide, hydrochlorothiazide, chlorothiazide, trichlormethiazide, and althiazide) for comparison with an existing structure for cyclothiazide. The structures detail how changes in the substituents in the 3- and 7-positions of the hydrobenzothiadiazide ring shift the orientation of the drug in the binding site and, in some cases, change the stoichiometry of binding. All derivatives maintain a hydrogen bond with the Ser754 hydroxyl, affirming the partial selectivity of the benzothiadiazides for the flip form of AMPA receptors. PMID:19673491

Impact of changes in blood pressure during the treatment of acute decompensated heart failure on renal and clinical outcomes†

PubMed Central

Testani, Jeffrey M.; Coca, Steven G.; McCauley, Brian D.; Shannon, Richard P.; Kimmel, Stephen E.

2011-01-01

Aims One of the primary determinants of blood flow in regional vascular beds is perfusion pressure. Our aim was to investigate if reduction in blood pressure during the treatment of decompensated heart failure would be associated with worsening renal function (WRF). Our secondary aim was to evaluate the prognostic significance of this potentially treatment-induced form of WRF. Methods and results Subjects included in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial limited data were studied (386 patients). Reduction in systolic blood pressure (SBP) was greater in patients experiencing WRF (−10.3 ± 18.5 vs. −2.8 ± 16.0 mmHg, P < 0.001) with larger reductions associated with greater odds for WRF (odds ratio = 1.3 per 10 mmHg reduction, P < 0.001). Systolic blood pressure reduction (relative change > median) was associated with greater doses of in-hospital oral vasodilators (P ≤ 0.017), thiazide diuretic use (P = 0.035), and greater weight reduction (P = 0.023). In patients with SBP-reduction, WRF was not associated with worsened survival [adjusted hazard ratio (HR) = 0.76, P = 0.58]. However, in patients without SBP-reduction, WRF was strongly associated with increased mortality (adjusted HR = 5.3, P < 0.001, P interaction = 0.001). Conclusion During the treatment of decompensated heart failure, significant blood pressure reduction is strongly associated with WRF. However, WRF that occurs in the setting of SBP-reduction is not associated with an adverse prognosis, whereas WRF in the absence of this provocation is strongly associated with increased mortality. These data suggest that WRF may represent the final common pathway of several mechanistically distinct processes, each with potentially different prognostic implications. PMID:21693504

Impact of changes in blood pressure during the treatment of acute decompensated heart failure on renal and clinical outcomes.

PubMed

Testani, Jeffrey M; Coca, Steven G; McCauley, Brian D; Shannon, Richard P; Kimmel, Stephen E

2011-08-01

One of the primary determinants of blood flow in regional vascular beds is perfusion pressure. Our aim was to investigate if reduction in blood pressure during the treatment of decompensated heart failure would be associated with worsening renal function (WRF). Our secondary aim was to evaluate the prognostic significance of this potentially treatment-induced form of WRF. Subjects included in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial limited data were studied (386 patients). Reduction in systolic blood pressure (SBP) was greater in patients experiencing WRF (-10.3 ± 18.5 vs. -2.8 ± 16.0 mmHg, P < 0.001) with larger reductions associated with greater odds for WRF (odds ratio = 1.3 per 10 mmHg reduction, P < 0.001). Systolic blood pressure reduction (relative change > median) was associated with greater doses of in-hospital oral vasodilators (P ≤ 0.017), thiazide diuretic use (P = 0.035), and greater weight reduction (P = 0.023). In patients with SBP-reduction, WRF was not associated with worsened survival [adjusted hazard ratio (HR) = 0.76, P = 0.58]. However, in patients without SBP-reduction, WRF was strongly associated with increased mortality (adjusted HR = 5.3, P < 0.001, P interaction = 0.001). During the treatment of decompensated heart failure, significant blood pressure reduction is strongly associated with WRF. However, WRF that occurs in the setting of SBP-reduction is not associated with an adverse prognosis, whereas WRF in the absence of this provocation is strongly associated with increased mortality. These data suggest that WRF may represent the final common pathway of several mechanistically distinct processes, each with potentially different prognostic implications.

[Diuretic-based therapy].

PubMed

Presne, Claire; Monge, Matthieu; Mansour, Janette; Oprisiu, Roxana; Choukroun, Gabriel; Achard, Jean Michel; Fournier, Albert

2007-10-01

Diuretics are pharmacological agents that increase natriuresis through inhibition of tubular re-absorption of sodium. The mechanisms and site of this inhibition differ with each drug class, accounting for their additive effects on natriuresis increase and their hydroelectrolytic side effects. The response to a given diuretic dose depends on the diuretic concentration on the urine at its action site. This concentration may be decreased by pharmacokinetic factors such as encountered in renal insufficiency or in nephrotic syndrome. These resistance mechanisms of diuretics may be corrected by dose increase, previous diuretic fixation on albumin or warfarin administration. Once these mechanisms are opposed, the diuretic concentration for maximal efficacy is reached at is action site and the natriuresis obtained as the normal maximal plateau. This is not the case when an oedematous systemic disease with effective hypovolemia is present, like in heart failure or cirrhosis, or when chronic use of loop diuretics has induced a hypertrophy of the more distant part of the tubule. In theses cases, a pharmacodynamic resistance exists, resulting in a lower maximal natriuresis plateau in spite of adequate concentration of the diuretic at its action site, even in the absence of pharmacokinetic resistance factors. The main indications of diuretics are systemic oedematous disease and hypertension. In the oedematous diseases, diuretics indication is both straightforward and sufficient only if effective hypervolemia is present. The therapeutic approach is discussed according to the various clinical conditions and pathophysiological background. In uncomplicated hypertension, diuretics are the cornerstone of the therapy. The most suitable diuretic treatment for hypertension is an association of low doses thiazide (12.5-50 mg/day) with potassium sparing diuretics. Rare indications of diuretics are also reviewed.

Drug allergies documented in electronic health records of a large healthcare system.

PubMed

Zhou, L; Dhopeshwarkar, N; Blumenthal, K G; Goss, F; Topaz, M; Slight, S P; Bates, D W

2016-09-01

The prevalence of drug allergies documented in electronic health records (EHRs) of large patient populations is understudied. We aimed to describe the prevalence of common drug allergies and patient characteristics documented in EHRs of a large healthcare network over the last two decades. Drug allergy data were obtained from EHRs of patients who visited two large tertiary care hospitals in Boston from 1990 to 2013. The prevalence of each drug and drug class was calculated and compared by sex and race/ethnicity. The number of allergies per patient was calculated and the frequency of patients having 1, 2, 3…, or 10+ drug allergies was reported. We also conducted a trend analysis by comparing the proportion of each allergy to the total number of drug allergies over time. Among 1 766 328 patients, 35.5% of patients had at least one reported drug allergy with an average of 1.95 drug allergies per patient. The most commonly reported drug allergies in this population were to penicillins (12.8%), sulfonamide antibiotics (7.4%), opiates (6.8%), and nonsteroidal anti-inflammatory drugs (NSAIDs) (3.5%). The relative proportion of allergies to angiotensin-converting enzyme (ACE) inhibitors and HMG CoA reductase inhibitors (statins) have more than doubled since early 2000s. Drug allergies were most prevalent among females and white patients except for NSAIDs, ACE inhibitors, and thiazide diuretics, which were more prevalent in black patients. Females and white patients may be more likely to experience a reaction from common medications. An increase in reported allergies to ACE inhibitors and statins is noteworthy. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The effects of genes implicated in cardiovascular disease on blood-pressure response to treatment among treatment-naïve hypertensive African Americans in the GenHAT study

PubMed Central

Do, Anh N; Lynch, Amy I; Claas, Steven A; Boerwinkle, Eric; Davis, Barry R; Ford, Charles E; Eckfeldt, John H; Tiwari, Hemant K; Arnett, Donna K; Irvin, Marguerite R

2015-01-01

African Americans have the highest prevalence of hypertension in the United States. Blood-pressure control is important to reduce cardiovascular disease (CVD)-related morbidity and mortality in this ethnic group. Genetic variants have been found to be associated with BP response to treatment. Previous pharmacogenetic studies of blood-pressure response to treatment in African Americans suffer limitations of small sample size as well as a limited number of candidate genes, and often focused on one antihypertensive treatment. Using 1,131 African-American treatment naïve participants from the Genetics of Hypertension Associated Treatment (GenHAT) Study, we examined whether variants in 35 candidate genes might modulate blood-pressure response to four different antihypertensive medications, including an angiotensin converting enzyme (ACE) inhibitor (lisinopril), a calcium channel blocker (amlodipine), and an α-adrenergic blocker (doxazosin) as compared to a thiazide diuretic (chlorthalidone) after 6 months of follow-up. Several suggestive gene by treatment interactions were identified. For example, among participants with two minor alleles of REN rs6681776, diastolic blood-pressure response was much improved on doxazosin compared to chlorthalidone (on average −9.49 mmHg vs. −1.70 mmHg) (P=0.007). Although several suggestive loci were identified, none of the findings passed significance criteria after correction for multiple testing. Given the impact of hypertension and its sequelae in this population, this research highlights the potential for genetic factors to contribute to blood-pressure response to treatment. Continued concerted research efforts focused on genetics are needed to improve treatment response in this high risk group. PMID:26791477

[Case of distal renal tubular acidosis complicated with renal diabetes insipidus, showing aggravation of symptoms with occurrence of diabetes mellitus].

PubMed

Liu, Hexing; Tomoda, Fumihiro; Koike, Tsutomu; Ohara, Maiko; Nakagawa, Taizo; Kagitani, Satoshi; Inoue, Hiroshi

2011-01-01

We report herein a 27-year-old male case of inherited distal renal tubular acidosis complicated with renal diabetes insipidus, the symptoms of which were aggravated by the occurrence of diabetes mellitus. At 2 months after birth, he was diagnosed as having inherited distal renal tubular acidosis and thereafter supplementation of both potassium and alkali was started to treat his hypokalemia and metabolic acidosis. At the age of 4 years, calcification of the bilateral renal medulla was detected by computed tomography. Subsequently his urinary volume gradually increased and polyuria of approximately 4 L/day persisted. At the age of 27 years, he became fond of sugar-sweetened drinks and also often forgot to take the medicine. He was admitted to our hospital due to polyuria of more than 10 L day, muscle weakness and gait disturbance. Laboratory tests disclosed worsening of both hypokalemia and metabolic acidosis in addition to severe hyperglycemia. It seemed likely that occurrence of diabetes mellitus and cessation of medications can induce osmotic diuresis and aggravate hypokalemia and metabolic acidosis. Consequently, severe dehydration, hypokalemia-induced damage of his urinary concentration ability and enhancement of the renin angiotensin system occurred and thereby possibly worsened his hypokalemia and metabolic acidosis. As normalization of hyperglycemia and metabolic acidosis might have exacerbated hypokalemia further, dehydration and hypokalemia were treated first. Following intensive treatment, these abnormalities were improved, but polyuria persisted. Elevated plasma antidiuretic hormone (12.0 pg/mL) and deficit of renal responses to antidiuretic hormone suggested that the polyuria was attributable to the preexisting renal diabetes insipidus possibly caused by bilateral renal medulla calcification. Thiazide diuretic or nonsteroidal anti-inflammatory drugs were not effective for the treatment of diabetes insipidus in the present case.

[Vasopressin V2 receptor-related pathologies: congenital nephrogenic diabetes insipidus and nephrogenic syndrome of inappropiate antidiuresis].

PubMed

Morin, Denis

2014-12-01

Congenital nephrogenic diabetes insipidus is a rare hereditary disease with mainly an X-linked inheritance (90% of the cases) but there are also autosomal recessive and dominant forms. Congenital nephrogenic diabetes insipidus is characterized by a resistance of the renal collecting duct to the action of the arginine vasopressin hormone responsible for the inability of the kidney to concentrate urine. The X-linked form is due to inactivating mutations of the vasopressin 2 receptor gene leading to a loss of function of the mutated receptors. Affected males are often symptomatic in the neonatal period with a lack of weight gain, dehydration and hypernatremia but mild phenotypes may also occur. Females carrying the mutation may be asymptomatic but, sometimes, severe polyuria is found due to the random X chromosome inactivation. The autosomal recessive and dominant forms, occurring in both genders, are linked to mutations in the aquaporin-2 gene. The treatment remains difficult, especially in infants, and is based on a low osmotic diet with increased water intake and the use of thiazides and indomethacin. The main goal is to avoid hypernatremic episodes and maintain a good hydration state. Potentially, specific treatment, in some cases of X-linked congenital nephrogenic diabetes insipidus, with pharmacological chaperones such as non-peptide vasopressin-2 receptor antagonists will be available in the future. Conversely, the nephrogenic syndrome of inappropriate antidiuresis (NSIAD) is linked to a constitutive activation of the V(2)-receptor due to activating mutations with clinical and biological features of inappropriate antidiuresis but with low or undetectable plasma arginine vasopressin hormone levels. Copyright © 2014 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

Regression of albuminuria and hypertension and arrest of severe renal injury by a losartan-hydrochlorothiazide association in a model of very advanced nephropathy.

PubMed

Arias, Simone Costa Alarcon; Valente, Carla Perez; Machado, Flavia Gomes; Fanelli, Camilla; Origassa, Clarice Silvia Taemi; de Brito, Thales; Camara, Niels Olsen Saraiva; Malheiros, Denise Maria Avancini Costa; Zatz, Roberto; Fujihara, Clarice Kazue

2013-01-01

Treatments that effectively prevent chronic kidney disease (CKD) when initiated early often yield disappointing results when started at more advanced phases. We examined the long-term evolution of renal injury in the 5/6 nephrectomy model (Nx) and the effect of an association between an AT-1 receptor blocker, losartan (L), and hydrochlorothiazide (H), shown previously to be effective when started one month after Nx. Adult male Munich-Wistar rats underwent Nx, being divided into four groups: Nx+V, no treatment; Nx+L, receiving L monotherapy; Nx+LH, receiving the L+H association (LH), and Nx+AHHz, treated with the calcium channel blocker, amlodipine, the vascular relaxant, hydralazine, and H. This latter group served to assess the effect of lowering blood pressure (BP). Rats undergoing sham nephrectomy (S) were also studied. In a first protocol, treatments were initiated 60 days after Nx, when CKD is at a relatively early stage. In a second protocol, treatments were started 120 days after Nx, when glomerulosclerosis and interstitial fibrosis are already advanced. In both protocols, L treatment promoted only partial renoprotection, whereas LH brought BP, albuminuria, tubulointerstitial cell proliferation and plasma aldosterone below pretreatment levels, and completely detained progression of renal injury. Despite normalizing BP, the AHHz association failed to prevent renal damage, indicating that the renoprotective effect of LH was not due to a systemic hemodynamic action. These findings are inconsistent with the contention that thiazides are innocuous in advanced CKD. In Nx, LH promotes effective renoprotection even at advanced stages by mechanisms that may involve anti-inflammatory and intrarenal hemodynamic effects, but seem not to require BP normalization.

An Evaluation of a Clinical Pharmacy-Directed Intervention on Blood Pressure Control

PubMed Central

Kicklighter, Caroline E.; Nelson, Kent M.; Humphries, Tammy L.; Delate, Thomas

Objective To compare short and long term blood pressure control with clinical pharmacy specialist involvement to traditional physician management. Setting A non-profit health maintenance organization in the United States covering approximately 385,000 lives. Methods This analysis utilized a prospective parallel design. Adult patients with a baseline Blood pressure>140/90 mmHg and receiving at least one antihypertensive medication were eligible for the study. Eligible hypertension management patients at one medical office were referred to the office’s clinical pharmacy specialist (intervention cohort) while at another comparable medical office they received usual physician-directed care (control cohort). The primary outcome measure was achievement of a goal BP (<140/90 mmHg) during a six month follow-up. Medical records were also reviewed approximately 1.5 years post enrollment to assess long-term BP control after clinical pharmacy-managed patients returned to usual care. Multivariate analyses were performed to adjust for baseline cohort differences. Results One hundred-thirteen and 111 subjects in the intervention and control cohorts completed the study, respectively. At the end of the follow-up period, clinical pharmacy-managed subjects were more likely to have achieved goal BP (64.6%) and received a thiazide diuretic (68.1%) compared to control subjects (40.7% and 33.3%, respectively) (adjusted p=0.002 and p<0.001, respectively). The proportion of clinical pharmacy-managed subjects with controlled BP decreased to 22.2% after returning to usual care (p<0.001). Conclusion Clinical pharmacy involvement in hypertension management resulted in increased BP control. Loss of long-term control after discontinuation of clinical pharmacy management supports a change in care processes that prevent patients from being lost to follow-up. PMID:25214896

Factors associated with appendicular bone mass in older women. The Study of Osteoporotic Fractures Research Group.

PubMed

Bauer, D C; Browner, W S; Cauley, J A; Orwoll, E S; Scott, J C; Black, D M; Tao, J L; Cummings, S R

1993-05-01

To determine the factors associated with appendicular bone mass in older women. Cross-sectional analysis of baseline data collected for a multicenter, prospective study of osteoporotic fractures. Four clinical centers in Baltimore, Maryland; Minneapolis, Minnesota; Portland, Oregon; and the Monongahela valley, Pennsylvania. A total of 9704 ambulatory, nonblack women, ages 65 years or older, recruited from population-based listings. Demographic and historical information and anthropometric measurements were obtained from a baseline questionnaire, interview, and examination. Single-photon absorptiometry scans were obtained at three sites: the distal radius, midradius, and calcaneus. Multivariate associations with bone mass were first examined in a randomly selected half of the cohort (training group) and were then tested on the other half of the cohort (validation group). In order of decreasing strength of association, estrogen use, non-insulin-dependent diabetes, thiazide use, increased weight, greater muscle strength, later age at menopause, and greater height were independently associated with higher bone mass. Gastric surgery, age, history of maternal fracture, smoking, and caffeine intake were associated with lower bone mass (all P < 0.05). For example, we found that 2 or more years of estrogen use was associated with a 7.2% increase in distal radius bone mass, whereas gastrectomy was associated with an 8.2% decrease in bone mass. The associations between bone mass and dietary calcium intake and rheumatoid arthritis were inconsistent. Alcohol use, physical activity, use of calcium supplements, pregnancy, breast-feeding, parental nationality, and hair color were among the many variables not associated with bone mass. Multivariate models accounted for 20% to 35% of the total variance of bone mass. A large number of factors influence the bone mass of elderly women; however, age, weight, muscle strength, and estrogen use are the most important factors.

Targeting nocturnal hypertension in type 2 diabetes mellitus.

PubMed

Rossen, Niklas Blach; Knudsen, Søren Tang; Fleischer, Jesper; Hvas, Anne-Mette; Ebbehøj, Eva; Poulsen, Per Løgstrup; Hansen, Klavs Würgler

2014-11-01

Several studies in different populations have suggested that nighttime blood pressure (BP) is a stronger predictor of cardiovascular events than daytime BP. Consequently, treatment strategies to target nighttime BP have come into focus. The aim of the present study was to investigate the effect of change of administration time of antihypertensive drugs. We included 41 patients with type 2 diabetes mellitus and nocturnal hypertension (nighttime systolic BP >120 mm Hg) in an open-label, crossover study. Patients were randomized to 8 weeks of either morning or bedtime administration of all of the individual's once-daily antihypertensive drugs, followed by 8 weeks of switched dosing regimen. Bedtime administration of antihypertensive drugs resulted in a significant reduction in nighttime (7.5 mm Hg; P<0.001) and 24-hour (3.1 mm Hg; P=0.014) systolic BP, with a nonsignificant reduction in daytime (1.3 mm Hg; P=0.336) systolic BP. We did not find morning BP surge to be different between dosing regimens. Levels of C-reactive protein were significantly lower with bedtime administration, which may indicate an effect on low-grade inflammation. We found no difference in urinary albumin excretion, regardless of albuminuria status. Urinary sodium/creatinine was significantly increased and urinary osmolality significantly reduced with bedtime administration, which can be interpreted as increased nocturnal natriuresis. In patients with type 2 diabetes mellitus and nocturnal hypertension, administration of once-daily antihypertensive drugs at bedtime may be favorable. The increased nocturnal natriuresis may reflect increased effect of bedtime-administered thiazides and renin-angiotensin system inhibitors, suggesting a potential mechanism of the observed effects on BP with chronotherapeutic intervention. © 2014 American Heart Association, Inc.

Incidence and determinants of hyperkalemia and hypokalemia in a large healthcare system.

PubMed

Nilsson, Erik; Gasparini, Alessandro; Ärnlöv, Johan; Xu, Hairong; Henriksson, Karin M; Coresh, Josef; Grams, Morgan E; Carrero, Juan Jesus

2017-10-15

Hypo- and hyperkalemia in clinical settings are insufficiently characterized and large-scale data from Europe lacking. We studied incidence and determinants of these abnormalities in a large Swedish healthcare system. Observational study from the Stockholm CREAtinine Measurements project, including adult individuals from Stockholm accessing healthcare in 2009 (n=364,955). Over 3-years, we estimated the incidence of hypokalemia, defined as potassium<3.5mmol/L, hyperkalemia, defined as potassium>5mmol/L, and moderate/severe hyperkalemia, defined as potassium>5.5mmol/L. Kidney function was assessed by estimated glomerular filtration rate (eGFR). Of 364,955 participants, 69.4% had 1-2 potassium tests, 16.7% had 3-4 tests and the remaining 13.9% had >4potassiumtests/year. Hypokalemia occurred in 49,662 (13.6%) individuals, with 33% recurrence. Hyperkalemia occurred in 25,461 (7%) individuals, with 35.7% recurrence. Moderate/severe hyperkalemia occurred in 9059 (2.5%) with 28% recurrence. The frequency of potassium testing was an important determinant of dyskalemia risk. The incidence proportion of hyperkalemia was higher in the presence of diabetes, lower eGFR, myocardial infarction, heart failure (HF), or use of renin angiotensin-aldosterone system inhibitors (RAASi). In adjusted analyses, women and use of loop/thiazide diuretics were associated with lower hyperkalemia risk. Older age, lower eGFR, diabetes, HF and use of RAASi were associated with higher hyperkalemia risk. On the other hand, women, younger age, higher eGFR and baseline use of diuretics were associated with higher hypokalemia risk. Hypo- and hyperkalemia are common in healthcare. Optimal RAASi and diuretics use and careful potassium monitoring in the presence of certain comorbidities, especially lower eGFR, is advocated. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Antihypertensive Medications and the Prevalence of Hyperkalemia in a Large Health System

PubMed Central

Chang, Alex R.; Sang, Yingying; Leddy, Julia; Yahya, Taher; Kirchner, H. Lester; Inker, Lesley A.; Matsushita, Kunihiro; Ballew, Shoshana H.; Coresh, Josef; Grams, Morgan E.

2016-01-01

Little is known about the frequency and patterns of hyperkalemia in clinical settings. We evaluated the association between baseline antihypertensive medications that may affect potassium levels (angiotensin converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), beta-blockers, loop/thiazide diuretics, and potassium-sparing diuretics) and hyperkalemia, defined by potassium >5 mEq/L and >5.5 mEq/L, over a 3-year time period in 194,456 outpatients in the Geisinger Health System, as well as actions taken after an episode of hyperkalemia. The proportions of patients with 0, <2, 2–4, and ≥4 potassium measurements per year were 20%, 58%, 16%, and 6%. Potassium levels >5 mEq/L and >5.5 mEq/L occurred in 10.8% and 2.3% of all patients over the 3-year period; among patients with ≥4 measurements per year, corresponding values were 39.4% and 14.6%. Most cases of hyperkalemia occurred only once during follow-up. The antihypertensive medication class most strongly associated with hyperkalemia was ACEIs. Among patients with a measurement of potassium >5.5 mEq/L, only 24% were seen by a nephrologist and 5.2% were seen by a dietician during the 3-year period. Short-term actions after a potassium measurement >5.5 mEq/L included emergency room visit (3.1% within 7 days), re-measurement of potassium (44.3% with 14 days), and change in a potassium-altering medication (26.4% within 60 days). The most common medication changes were discontinuation/dose reduction of an ACEI/ARB or potassium-sparing diuretic, which occurred in 29.1% and 49.6% of persons taking these medications, respectively. In conclusion, hyperkalemia is common. Future research may enable optimal RAAS inhibitor use with improved management of hyperkalemia. PMID:27067721

P2Y2 receptor activation inhibits the expression of the sodium-chloride cotransporter NCC in distal convoluted tubule cells.

PubMed

Gailly, P; Szutkowska, M; Olinger, E; Debaix, H; Seghers, F; Janas, S; Vallon, V; Devuyst, O

2014-11-01

Luminal nucleotide stimulation is known to reduce Na(+) transport in the distal nephron. Previous studies suggest that this mechanism may involve the thiazide-sensitive Na(+)-Cl(-) cotransporter (NCC), which plays an essential role in NaCl reabsorption in the cells lining the distal convoluted tubule (DCT). Here we show that stimulation of mouse DCT (mDCT) cells with ATP or UTP promoted Ca(2+) transients and decreased the expression of NCC at both mRNA and protein levels. Specific siRNA-mediated silencing of P2Y2 receptors almost completely abolished ATP/UTP-induced Ca(2+) transients and significantly reduced ATP/UTP-induced decrease of NCC expression. To test whether local variations in the intracellular Ca(2+) concentration ([Ca(2+)]i) may control NCC transcription, we overexpressed the Ca(2+)-binding protein parvalbumin selectively in the cytosol or in the nucleus of mDCT cells. The decrease in NCC mRNA upon nucleotide stimulation was abolished in cells overexpressing cytosolic PV but not in cells overexpressing either a nuclear-targeted PV or a mutated PV unable to bind Ca(2+). Using a firefly luciferase reporter gene strategy, we observed that the activity of NCC promoter region from -1 to -2,200 bp was not regulated by changes in [Ca(2+)]i. In contrast, high cytosolic calcium level induced instability of NCC mRNA. We conclude that in mDCT cells: (1) P2Y2 receptor is essential for the intracellular Ca(2+) signaling induced by ATP/UTP stimulation; (2) P2Y2-mediated increase of cytoplasmic Ca(2+) concentration down-regulates the expression of NCC; (3) the decrease of NCC expression occurs, at least in part, via destabilization of its mRNA.

A role for the circadian clock protein Per1 in the regulation of the NaCl co-transporter (NCC) and the with-no-lysine kinase (WNK) cascade in mouse distal convoluted tubule cells.

PubMed

Richards, Jacob; Ko, Benjamin; All, Sean; Cheng, Kit-Yan; Hoover, Robert S; Gumz, Michelle L

2014-04-25

It has been well established that blood pressure and renal function undergo circadian fluctuations. We have demonstrated that the circadian protein Per1 regulates multiple genes involved in sodium transport in the collecting duct of the kidney. However, the role of Per1 in other parts of the nephron has not been investigated. The distal convoluted tubule (DCT) plays a critical role in renal sodium reabsorption. Sodium is reabsorbed in this segment through the actions of the NaCl co-transporter (NCC), which is regulated by the with-no-lysine kinases (WNKs). The goal of this study was to test if Per1 regulates sodium transport in the DCT through modulation of NCC and the WNK kinases, WNK1 and WNK4. Pharmacological blockade of nuclear Per1 entry resulted in decreased mRNA expression of NCC and WNK1 but increased expression of WNK4 in the renal cortex of mice. These findings were confirmed by using Per1 siRNA and pharmacological blockade of Per1 nuclear entry in mDCT15 cells, a model of the mouse distal convoluted tubule. Transcriptional regulation was demonstrated by changes in short lived heterogeneous nuclear RNA. Chromatin immunoprecipitation experiments demonstrated interaction of Per1 and CLOCK with the promoters of NCC, WNK1, and WNK4. This interaction was modulated by blockade of Per1 nuclear entry. Importantly, NCC protein expression and NCC activity, as measured by thiazide-sensitive, chloride-dependent (22)Na uptake, were decreased upon pharmacological inhibition of Per1 nuclear entry. Taken together, these data demonstrate a role for Per1 in the transcriptional regulation of NCC, WNK1, and WNK4.

Mechanisms of angiotensin II stimulation of NCC are time-dependent in mDCT15 cells.

PubMed

Ko, Benjamin; Mistry, Abinash; Hanson, Lauren; Mallick, Rickta; Hoover, Robert S

2015-04-01

Angiotensin II (ANG II) increases thiazide-sensitive sodium-chloride cotransporter (NCC) activity both acutely and chronically. ANG II has been implicated as a switch that turns WNK4 from an inhibitor of NCC into an activator of NCC, and ANG II's effect on NCC appears to require WNK4. Chronically, ANG II stimulation of NCC results in an increase in total and phosphorylated NCC, but the role of NCC phosphorylation in acute ANG II actions is unclear. Here, using a mammalian cell model with robust native NCC activity, we corroborate the role that ANG II plays in WNK4 regulation and clarify the role of Ste20-related proline alanine-rich kinase (SPAK)-induced NCC phosphorylation in ANG II action. ANG II was noted to have a biphasic effect on NCC, with a peak increase in NCC activity in the physiologic range of 10(-11) M ANG II. This effect was apparent as early as 15 min and remained sustained through 120 min. These changes correlated with significant increases in NCC surface protein expression. Knockdown of WNK4 expression sharply attenuated the effect of ANG II. SPAK knockdown did not affect ANG II action at early time points (15 and 30 min), but it did attenuate the response at 60 min. Correspondingly, NCC phosphorylation did not increase at 15 or 30 min, but increased significantly at 60 min. We therefore conclude that within minutes of an increase in ANG II, NCC is rapidly trafficked to the cell surface in a phosphorylation-independent but WNK4-dependent manner. Then, after 60 min, ANG II induces SPAK-dependent phosphorylation of NCC.

Mechanisms of angiotensin II stimulation of NCC are time-dependent in mDCT15 cells

PubMed Central

Mistry, Abinash; Hanson, Lauren; Mallick, Rickta; Hoover, Robert S.

2015-01-01

Angiotensin II (ANG II) increases thiazide-sensitive sodium-chloride cotransporter (NCC) activity both acutely and chronically. ANG II has been implicated as a switch that turns WNK4 from an inhibitor of NCC into an activator of NCC, and ANG II's effect on NCC appears to require WNK4. Chronically, ANG II stimulation of NCC results in an increase in total and phosphorylated NCC, but the role of NCC phosphorylation in acute ANG II actions is unclear. Here, using a mammalian cell model with robust native NCC activity, we corroborate the role that ANG II plays in WNK4 regulation and clarify the role of Ste20-related proline alanine-rich kinase (SPAK)-induced NCC phosphorylation in ANG II action. ANG II was noted to have a biphasic effect on NCC, with a peak increase in NCC activity in the physiologic range of 10−11 M ANG II. This effect was apparent as early as 15 min and remained sustained through 120 min. These changes correlated with significant increases in NCC surface protein expression. Knockdown of WNK4 expression sharply attenuated the effect of ANG II. SPAK knockdown did not affect ANG II action at early time points (15 and 30 min), but it did attenuate the response at 60 min. Correspondingly, NCC phosphorylation did not increase at 15 or 30 min, but increased significantly at 60 min. We therefore conclude that within minutes of an increase in ANG II, NCC is rapidly trafficked to the cell surface in a phosphorylation-independent but WNK4-dependent manner. Then, after 60 min, ANG II induces SPAK-dependent phosphorylation of NCC. PMID:25651566

PI3K/Akt Signaling Pathway Activates the WNK-OSR1/SPAK-NCC Phosphorylation Cascade in Hyperinsulinemic db/db Mice

PubMed Central

Nishida, Hidenori; Sohara, Eisei; Nomura, Naohiro; Chiga, Motoko; Alessi, Dario R; Rai, Tatemitsu; Sasaki, Sei; Uchida, Shinichi

2013-01-01

Metabolic syndrome patients have insulin resistance, which causes hyperinsulinemia, which in turn causes aberrant increased renal sodium reabsorption. The precise mechanisms underlying this greater salt-sensitivity of hyperinsulinemic patients remain unclear. Abnormal activation of the recently-identified WNK kinase-OSR1/SPAK kinases-NCC transporter phosphorylation cascade results in the salt-sensitive hypertension of pseudohypoaldosteronism type II. Here, we report a study of renal WNK-OSR1/SPAK-NCC cascade activation in the db/db mouse model of hyperinsulinemic metabolic syndrome. Thiazide sensitivity was increased, suggesting greater activity of NCC in db/db mice. In fact, increased phosphorylation of OSR1/SPAK and NCC was observed. In both SpakT243A/+ and Osr1T185A/+ knock-in db/db mice, which carry mutations that disrupt the signal from WNK kinases, increased phosphorylation of NCC and elevated blood pressure were completely corrected, indicating that phosphorylation of SPAK and OSR1 by WNK kinases is required for the increased activation and phosphorylation of NCC in this model. Renal phosphorylated Akt was increased in db/db mice, suggesting that increased NCC phosphorylation is regulated by the PI3K/Akt signaling cascade in the kidney in response to hyperinsulinemia. A PI3K inhibitor (NVP-BEZ235) corrected the increased OSR1/SPAK-NCC phosphorylation. Another more specific PI3K inhibitor (GDC-0941) and an Akt inhibitor (MK-2206) also inhibited increased NCC phosphorylation. These results indicate that the PI3K/Akt signaling pathway activates the WNK-OSR1/SPAK-NCC phosphorylation cascade in db/db mice. This mechanism may play a role in the pathogenesis of salt-sensitive hypertension in human hyperinsulinemic conditions such as the metabolic syndrome. PMID:22949526

Double knockout of carbonic anhydrase II (CAII) and Na(+)-Cl(-) cotransporter (NCC) causes salt wasting and volume depletion.

PubMed

Xu, Jie; Barone, Sharon; Brooks, Mary-Beth; Soleimani, Manoocher

2013-01-01

The thiazide-sensitive Na(+)-Cl(-) cotransporter NCC and the Cl(-)/HCO3(-)exchanger pendrin are expressed on apical membranes of distal cortical nephron segments and mediate salt absorption, with pendrin working in tandem with the epithelial Na(+) channel (ENaC) and the Na(+)-dependent chloride/bicarbonate exchanger (NDCBE), whereas NCC is working by itself. A recent study showed that NCC and pendrin compensate for loss of each other under basal conditions, therefore masking the role that each plays in salt reabsorption. Carbonic anhydrase II (CAII, CA2 or CAR2) plays an important role in acid-base transport and salt reabsorption in the proximal convoluted tubule and acid-base transport in the collecting duct. Animals with CAII deletion show remodeling of intercalated cells along with the downregulation of pendrin. NCC KO mice on the other hand show significant upregulation of pendrin and ENaC. Neither model shows any significant salt wasting under baseline conditions. We hypothesized that the up-regulation of pendrin is essential for the prevention of salt wasting in NCC KO mice. To test this hypothesis, we generated NCC/CAII double KO (dKO) mice by crossing mice with single deletion of NCC and CAII. The NCC/CAII dKO mice displayed significant downregulation of pendrin, along with polyuria and salt wasting. As a result, the dKO mice developed volume depletion, which was associated with the inability to concentrate urine. We conclude that the upregulation of pendrin is essential for the prevention of salt and water wasting in NCC deficient animals and its downregulation or inactivation will result in salt wasting, impaired water conservation and volume depletion in the setting of NCC inactivation or inhibition. © 2014 S. Karger AG, Basel.

Effects of ACE inhibition and ANG II stimulation on renal Na-Cl cotransporter distribution, phosphorylation, and membrane complex properties

PubMed Central

Lee, Donna H.; Maunsbach, Arvid B.; Riquier-Brison, Anne D.; Nguyen, Mien T. X.; Fenton, Robert A.; Bachmann, Sebastian; Yu, Alan S.

2013-01-01

The renal distal tubule Na-Cl cotransporter (NCC) reabsorbs <10% of the filtered Na+ but is a key control point for blood pressure regulation by angiotensin II (ANG II), angiotensin-converting enzyme inhibitors (ACEI), and thiazide diuretics. This study aimed to determine whether NCC phosphorylation (NCCp) was regulated by acute (20–30 min) treatment with the ACEI captopril (12 μg/min × 20 min) or by a sub-pressor dose of ANG II (20 ng·kg−1·min−1) in Inactin-anesthetized rats. By immuno-EM, NCCp was detected exclusively in or adjacent to apical plama membranes (APM) in controls and after ACEI or ANG II treatment, while NCC total was detected in both APM and subapical cytoplasmic vesicles (SCV) in all conditions. In renal homogenates, neither ACEI nor ANG II treatment altered NCCp abundance, assayed by immunoblot. However, by density gradient fractionation we identified a pool of low-density APM in which NCCp decreased 50% in response to captopril and was restored during ANG II infusion, and another pool of higher-density APM that responded reciprocally, indicative of regulated redistribution between two APM pools. In both pools, NCCp was preferentially localized to Triton-soluble membranes. Blue Native gel electrophoresis established that APM NCCp localized to ∼700 kDa complexes (containing γ-adducin) while unphosphorylated NCC in intracellular membranes primarily localized to ∼400 kDa complexes: there was no evidence for native monomeric or dimeric NCC or NCCp. In summary, this study demonstrates that phosphorylated NCC, localized to multimeric complexes in the APM, redistributes in a regulated manner within the APM in response to ACEI and ANG II. PMID:23114965

Management of high blood pressure in Blacks: an update of the International Society on Hypertension in Blacks consensus statement.

PubMed

Flack, John M; Sica, Domenic A; Bakris, George; Brown, Angela L; Ferdinand, Keith C; Grimm, Richard H; Hall, W Dallas; Jones, Wendell E; Kountz, David S; Lea, Janice P; Nasser, Samar; Nesbitt, Shawna D; Saunders, Elijah; Scisney-Matlock, Margaret; Jamerson, Kenneth A

2010-11-01

Since the first International Society on Hypertension in Blacks consensus statement on the "Management of High Blood Pressure in African American" in 2003, data from additional clinical trials have become available. We reviewed hypertension and cardiovascular disease prevention and treatment guidelines, pharmacological hypertension clinical end point trials, and blood pressure-lowering trials in blacks. Selected trials without significant black representation were considered. In this update, blacks with hypertension are divided into 2 risk strata, primary prevention, where elevated blood pressure without target organ damage, preclinical cardiovascular disease, or overt cardiovascular disease for whom blood pressure consistently <135/85 mm Hg is recommended, and secondary prevention, where elevated blood pressure with target organ damage, preclinical cardiovascular disease, and/or a history of cardiovascular disease, for whom blood pressure consistently <130/80 mm Hg is recommended. If blood pressure is ≤10 mm Hg above target levels, monotherapy with a diuretic or calcium channel blocker is preferred. When blood pressure is >15/10 mm Hg above target, 2-drug therapy is recommended, with either a calcium channel blocker plus a renin-angiotensin system blocker or, alternatively, in edematous and/or volume-overload states, with a thiazide diuretic plus a renin-angiotensin system blocker. Effective multidrug therapeutic combinations through 4 drugs are described. Comprehensive lifestyle modifications should be initiated in blacks when blood pressure is ≥115/75 mm Hg. The updated International Society on Hypertension in Blacks consensus statement on hypertension management in blacks lowers the minimum target blood pressure level for the lowest-risk blacks, emphasizes effective multidrug regimens, and de-emphasizes monotherapy.

Mutations in Kelch-like 3 and Cullin 3 cause hypertension and electrolyte abnormalities

PubMed Central

Boyden, Lynn M.; Choi, Murim; Choate, Keith A.; Nelson-Williams, Carol J.; Farhi, Anita; Toka, Hakan R.; Tikhonova, Irina R.; Bjornson, Robert; Mane, Shrikant M.; Colussi, Giacomo; Lebel, Marcel; Gordon, Richard D.; Semmekrot, Ben A.; Poujol, Alain; Välimäki, Matti J.; De Ferrari, Maria E.; Sanjad, Sami A.; Gutkin, Michael; Karet, Fiona E.; Tucci, Joseph R.; Stockigt, Jim R.; Keppler-Noreuil, Kim M.; Porter, Craig C.; Anand, Sudhir K.; Whiteford, Margo L.; Davis, Ira D.; Dewar, Stephanie B.; Bettinelli, Alberto; Fadrowski, Jeffrey J.; Belsha, Craig W.; Hunley, Tracy E.; Nelson, Raoul D.; Trachtman, Howard; Cole, Trevor R. P.; Pinsk, Maury; Bockenhauer, Detlef; Shenoy, Mohan; Vaidyanathan, Priya; Foreman, John W.; Rasoulpour, Majid; Thameem, Farook; Al-Shahrouri, Hania Z.; Radhakrishnan, Jai; Gharavi, Ali G.; Goilav, Beatrice; Lifton, Richard P.

2012-01-01

Hypertension affects one billion people and is a principal reversible risk factor for cardiovascular disease. A rare Mendelian syndrome, pseudohypoaldosteronism type II (PHAII), featuring hypertension, hyperkalemia, and metabolic acidosis, has revealed previously unrecognized physiology orchestrating the balance between renal salt reabsorption versus K+ and H+ excretion1. We used exome sequencing to identify mutations in Kelch-like 3 (KLHL3) or Cullin 3 (CUL3) in 41 PHAII kindreds. KLHL3 mutations are either recessive or dominant, while CUL3 mutations are dominant and predominantly de novo. CUL3 and BTB-Kelch proteins such as KLHL3 are components of Cullin/RING E3 ligase complexes (CRLs) that ubiquitinate substrates bound to Kelch propeller domains2–8. Dominant KLHL3 mutations are clustered in short segments within the Kelch propeller and BTB domains implicated in substrate9 and Cullin5 binding, respectively. Diverse CUL3 mutations all result in skipping of exon 9, producing an in-frame deletion. Because dominant KLHL3 and CUL3 mutations both phenocopy recessive loss-of-function KLHL3 mutations, they may abrogate ubiquitination of KLHL3 substrates. Disease features are reversed by thiazide diuretics, which inhibit the Na-Cl cotransporter (NCC) in the distal nephron of the kidney; KLHL3 and CUL3 are expressed in this location, suggesting a mechanistic link between KLHL3/CUL3 mutations, increased Na-Cl reabsorption, and disease pathogenesis. These findings demonstrate the utility of exome sequencing in disease gene identification despite combined complexities of locus heterogeneity, mixed models of transmission, and frequent de novo mutation, and establish a fundamental role for KLHL3/CUL3 in blood pressure, K+, and pH homeostasis. PMID:22266938

Patients' need for more counseling on diet, exercise, and smoking cessation: results from the National Ambulatory Medical Care Survey.

PubMed

Heaton, Pamela C; Frede, Stacey M

2006-01-01

To determine the percentage of physicians who reported counseling patients on diet/nutrition, exercise, weight reduction, or smoking cessation during their office visits when responding to the 2002 National Ambulatory Medical Care Survey (NAMCS). We sought to establish whether patients are receiving adequate counseling from physicians on the basis of this nationwide survey. Retrospective database analysis. United States. Data included 184,668,007 physician visits for patients diagnosed with type 2 diabetes, hyperlipidemia, hypertension, or obesity; 140,362,102 physician visits for patients in which insulin/oral antidiabetics, antihyperlipidemia drugs, angiotensin-converting enzyme inhibitors, thiazide diuretics, or weight loss drugs were prescribed; and 82,317,640 physician visits for patients who smoked or used tobacco. Not applicable. Frequency of responses for counseling/education/therapy about diet/nutrition, exercise, weight reduction, and tobacco use/exposure. For patients with type 2 diabetes, hyperlipidemia, or hypertension, or patients receiving a drug in one of the drug classes that may indicate the presence of these diseases, patients did not receive any type of diet or exercise counseling during more than one half of all visits. Visits by patients who were diagnosed as obese were most likely to receive any type of counseling (80.2%). Of visits for patients who used tobacco, 78.6% did not include any counseling about smoking cessation. Patients are insufficiently counseled and educated about the need for lifestyle changes that can affect their risks for common chronic diseases. As accessible and ideally positioned health care providers, pharmacists could potentially affect the rising epidemic of obesity and other lifestyle-related diseases by filling this void.

Hypertension management: rationale for triple therapy based on mechanisms of action.

PubMed

Neutel, Joel M; Smith, David H G

2013-10-01

An estimated 25% of patients will require 3 antihypertensive agents to achieve blood pressure (BP) control; combination therapy is thus an important strategy in hypertension treatment. This review discusses the triple-therapy combination of an angiotensin receptor blocker (ARB) or direct renin antagonist (DRI) with a calcium channel blocker (CCB) and a diuretic, with a focus on mechanisms of action. Multiple physiologic pathways contribute to hypertension. Combining antihypertensive agents not only better targets the underlying pathways, but also helps blunt compensatory responses that may be triggered by single-agent therapy. DRIs and ARBs target the renin-angiotensin-aldosterone system (RAAS) at the initial and final steps, respectively, and both classes lower BP by reducing the effects of angiotensin-2; however, ARBs may trigger a compensatory increase in renin activity. Dihydropyridine CCBs target L-type calcium channels and lower BP through potent vasodilation, but can trigger compensatory activation of the sympathetic nervous system (SNS) and RAAS. Thiazide diuretics lower BP initially through sodium depletion and plasma volume reduction, followed by total peripheral resistance reduction, but can also trigger compensatory activation of the SNS and RAAS. The combination of an agent targeting the RAAS with a CCB and diuretic is rational, and triple combinations of valsartan/amlodipine/hydrochlorothiazide, olmesartan/amlodipine/hydrochlorothiazide, and aliskiren/amlodipine/hydrochlorothiazide have demonstrated greater effectiveness compared with their respective dual-component combinations. In addition, single-pill, fixed-dose combinations can address barriers to BP control including clinical inertia and poor adherence. Fixed-dose antihypertensive combination products capitalize on complementary mechanisms of action and have been shown to result in improved BP control. © 2012 John Wiley & Sons Ltd.

Renal effects of nifedipine in healthy normotensive volunteers. Effects of dose, formulation, duration of treatment, and chlorothiazide coadministration.

PubMed

Adebayo, G I; Coker, H A; Fagbure, F

1988-01-01

Renal effects of nifedipine were assessed in 3 groups of healthy normotensive volunteers. In the first group (N = 10), a single 20-mg dose of the slow-release formulation caused an increase in 8-h sodium excretion (P less than 0.025) and urine volume (P less than 0.005). Natriuresis (P less than 0.05) and diuresis (P less than 0.05) were still evident after 1 wk of pretreatment, but were significantly attenuated (P less than 0.05), in each case, compared to levels after a single dose. Natriuresis and diuresis after 2 wk of intake were indistinguishable from control levels. In another group of 8, a single 10 mg dose of the conventional formulation (capsule) effected natriuresis (P less than 0.01) and diuresis (P less than 0.001) similar to those associated with intake of a single 20-mg dose of the slow-release formulation. Natriuresis and diuresis associated with a 20-mg single dose of the conventional formulation were not different from control but were less than those following intake of the 10-mg dose (P less than 0.025 in each case). In the third group of 6, nifedipine, though weaker than chlorothiazide, promoted natriuresis (P less than 0.025) and diuresis (P less than 0.025) of the thiazide without augmenting its kaliuresis. In all the groups, there were no changes in creatinine clearance, and nifedipine did not alter kaliuresis. It is suggested that natriuretic and diuretic effects of nifedipine in healthy normotensive individuals are dependent on the dose employed, the formulation used, and the duration of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased urinary prostaglandin E2 metabolite: A potential therapeutic target of Gitelman syndrome.

PubMed

Peng, Xiaoyan; Jiang, Lanping; Chen, Chen; Qin, Yan; Yuan, Tao; Wang, Ou; Xing, Xiaoping; Li, Xuemei; Nie, Min; Chen, Limeng

2017-01-01

Gitelman syndrome (GS), an inherited autosomal recessive salt-losing renal tubulopathy caused by mutations in SLC12A3 gene, has been associated with normal prostaglandin E2 (PGE2) levels since 1995 by a study involving 11 clinically diagnosed patients. However, it is difficult to explain why cyclooxygenase-2 (COX2) inhibitors, which pharmacologically reduce PGE2 synthesis, are helpful to patients with GS, and few studies performed in the last 20 years have measured PGE2 levels. The relationships between the clinical manifestations and PGE2 levels were never thoroughly analyzed. This study involved 39 GS patients diagnosed by SLC12A3 gene sequencing. Plasma and 24-h urine samples as well as the clinical data were collected at admission. PGE2 and PGEM levels were detected in plasma and urine samples by enzyme immunoassays. The in vivo function of the sodium-chloride co-transporter (NCC) in GS patients was evaluated using a modified thiazide test. The association among PGE2 levels, clinical manifestations and the function of NCC in GS patients were analyzed. Significantly higher levels of urinary and plasma PGEM were observed in GS patients than in the healthy volunteers. Higher urinary PGEM levels indicated more severe clinical manifestations and NCC dysfunction estimated by the increase of Cl- clearance. A higher PGEM level was found in male GS patients, who showed earlier onset age and more severe hypokalemia, hypochloremia and metabolic alkalosis than female GS patients. No relationship between renin angiotensin aldosterone system activation and PGEM level was observed. Higher urinary PGEM levels indicated more severe clinical manifestations and NCC dysfunction in GS patients. COX2 inhibition might be a potential therapeutic target in GS patients with elevated PGEM levels.

Marketing medicines: charting the rise of modern therapeutics through a systematic review of adverts in UK medical journals (1950-1980).

PubMed

Green, A Richard; Haddad, Peter M; Aronson, Jeffrey K

2018-02-14

To examine how pharmaceutical products that were first marketed between 1950 and 1980 were promoted to physicians through advertisements and briefly review advertising regulations and accuracy of the advertisements in the light of modern knowledge. We systematically reviewed advertisements promoting drugs for specific therapeutic areas, namely central nervous system disorders (anxiety and sleep disorders, depression, psychoses, and Parkinson's disease), respiratory disorders, cardiovascular disorders, and gastrointestinal disorders. We examined about 800 issues of the British Medical Journal (1950-1980) and about 150 issues of World Medicine (1965-1984). Advertising material was minimally regulated until the mid-1970s. Many drugs were marketed with little preclinical or clinical knowledge and some with the expectation that prescribers would obtain further data. The peak of advertising occurred in parallel with the surge in the release of novel drugs during the 1960s, but declined markedly after the mid-1970s. Advertisements generally contained little useful prescribing information. The period we investigated saw the release of many novel pharmaceuticals in the therapeutic areas we examined, and many (or their class successors) still play important therapeutic roles, including benzodiazepines, tricyclic antidepressants, phenothiazines, levodopa, selective and non-selective β-adrenoceptor antagonists, thiazide diuretics, β-adrenoceptor agonists, and histamine H 2 receptor antagonists. Advertising pharmaceuticals in the BMJ and World Medicine in 1950-1980 was poorly regulated and often lacked rigour. However, advertisements were gradually modified in the light of increasing clinical pharmacological knowledge, and they reflect an exciting period for the introduction of many drugs that continue to be of benefit today. © 2018 The British Pharmacological Society.

Stability-Indicating HPTLC Method for Studying Stress Degradation Behavior of Sulbutiamine HCl

PubMed Central

Farid, Nehal F.; Abdelwahab, Nada S.

2016-01-01

Sulbutiamine (SUL) is an ester of thiazides with neurotropic action. A new stability indicating HPTLC method has been developed and validated for the determination of SUL in the presence of different degradation products. The drug was subjected to different stress conditions following ICH strategy such as hydrolytic degradation (neutral, alkaline and acidic hydrolysis), oxidation, photodegradation and dry heat degradation. The drug demonstrated degradation under all decomposition conditions except neutral hydrolysis and dry heat, where the drug was completely degraded with 0.1 N NaOH, 1 N HCl and 30% H2O2 while it was partially degradaed by 0.1 N HCl, 3% H2O2 and UV light. Structure elucidation of the resulting degradation products was performed using ESI-Q-MS–MS. A well-defined peak for SUL was obtained at Rf = 0.46 and was completely separated from all obtained degradation products. Chromatographic separation was carried out on HPTLC aluminum plates precoated with silica gel 60 F254 using acetone–methylene chloride–ammonia buffer (pH 8.5 ± 0.2) (7:3:0.5, v/v) as a developing system. Densitometric scanning of the separated peaks was performed at 254 nm. System suitability testing parameters were calculated to ascertain the quality performance of the developed method. The method was validated with respect to USP guidelines regarding accuracy, precision, specificity, robustness and ruggedness. Good correlation coefficients were achieved in the range of 0.4–5.0 µg/band, and the limit of detection and limit of quantitation were found to be 0.11 and 0.33 µg/band, respectively. The utility of the suggested method was verified by application to Arcalion forte® tablets where no interference from additives was found. PMID:26759487

Chronobiology of death in heart failure.

PubMed

Ribas, Nuria; Domingo, Maite; Gastelurrutia, Paloma; Ferrero-Gregori, Andreu; Rull, Pilar; Noguero, Mariana; Garcia, Carmen; Puig, Teresa; Cinca, Juan; Bayes-Genis, Antoni

2014-05-01

In the general population, heart events occur more often during early morning, on Mondays, and during winter. However, the chronobiology of death in heart failure has not been analyzed. The aim of this study was to determine the circadian, day of the week, and seasonal variability of all-cause mortality in chronic heart failure. This was an analysis of all consecutive heart failure patients followed in a heart failure unit from January 2003 to December 2008. The circadian moment of death was analyzed at 6-h intervals and was determined by reviewing medical records and by information provided by the relatives. Of 1196 patients (mean [standard deviation] age, 69 [13] years; 62% male), 418 (34.9%) died during a mean (standard deviation) follow-up of 29 (21) months. Survivors were younger, had higher body mass index, left ventricular ejection fraction, glomerular filtration rate, hemoglobin and sodium levels, and lower Framingham risk scores, amino-terminal pro-B type natriuretic peptide, troponin T, and urate values. They were more frequently treated with angiotensin receptor blockers, beta-blockers, mineralocorticoids receptor antagonists, digoxin, nitrates, hydralazine, statins, loop diuretics, and thiazides. The analysis of the circadian and weekly variability did not reveal significant differences between the four 6-h intervals or the days of the week. Mortality occurred more frequently during the winter (30.6%) compared with the other seasons (P = .024). All cause mortality does not follow a circadian pattern, but a seasonal rhythm in patients with heart failure. This finding is in contrast to the circadian rhythmicity of cardiovascular events reported in the general population. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Azilsartan medoxomil in the management of hypertension: an evidence-based review of its place in therapy

PubMed Central

Angeloni, Emiliano

2016-01-01

Background Azilsartan (AZI) is a relatively new angiotensin receptor blocker available for the treatment of any stage of hypertension, which was eventually given in combination with chlorthalidone (CLT). Objective To review pharmacology and clinical role of AZI monotherapy and AZI/CLT or AZI/amlodipine combination therapies for hypertension management. Methods PubMed, Embase, and Cochrane Library were searched using search terms “ azilsartan”, “chlorthalidone,” “pharmacology,” “pharmacokinetics,” “pharmacodynamics,” “pharmacoeconomics,” and “cost-effectiveness.” To obtain other relevant information, US Food and Drug Association as well as manufacturer prescribing information were also reviewed. Results Randomized controlled trials demonstrated AZI to be superior to other sartans, such as valsartan, olmesartan, and candesartan, in terms of 24-hour ambulatory blood pressure monitoring (ABPM) reduction with respect. That beneficial effect of azilsartan was also associated with similar safety profiles. When compared to other antihypertensive drugs, azilsartan was found to be superior to any angiotensin-converting enzyme inhibitor, including ramipril, in terms of ABPM results, and noninferior to amlodipine in terms of sleep-BP control. The association of AZI and CLT was then found to be superior to other sartans + thiazide combination therapies in terms of both BP lowering and goal achievement. The combination of AZI and amlodipine has also been tested in clinical trials, but compared only with placebo, demonstrating its superiority in terms of efficacy and similarity in terms of safety. Conclusion Azilsartan is a safe and effective treatment option for every stage of hypertension, both alone or in fixed-dose combination tablets with chlorthalidone or amlodipine. Beneficial effects of AZI were also noted in patients with any degree of renal impairment. In addition, safety profiles of AZI were similar to that of the placebo. PMID:27103882

Antihypertensive and anti-inflammatory actions of combined azilsartan and chlorthalidone in Dahl salt-sensitive rats on a high-fat, high-salt diet.

PubMed

Jin, Chunhua; O'Boyle, Sean; Kleven, Daniel T; Pollock, Jennifer S; Pollock, David M; White, John J

2014-08-01

Metabolic syndrome (MetS) and chronic kidney disease are global health issues. Metabolic syndrome induces hypertension and commonly results in renal damage. The optimal therapy for hypertension in MetS is unknown. Thiazide diuretics are first-line therapy; however, these drugs may have untoward effects. In the present study we investigated the effects of azilsartan (AZL), chlorthalidone (CLTD) and their combination on blood pressure and renal injury in a rodent model with features of MetS. Dahl salt-sensitive rats were fed high-fat (36% fat), high-salt (4% NaCl) diet. Groups were then treated with vehicle, AZL (3 mg/kg per day), CLTD (5 mg/kg per day) or AZL + CLTD. Mean arterial pressure was recorded continuously by telemetry. After 26 days, rats were killed humanely and their kidneys were harvested for histology. Both AZL and CLTD attenuated the rise in blood pressure compared with vehicle and the combination further reduced blood pressure compared with CLTD alone. All treatments reduced proteinuria and albuminuria. Nephrinuria was prevented only in groups treated with AZL. Nephrinuria was 57% lower and proteinuria was 47% lower with combination therapy compared with AZL alone. All treatments reduced the number of inflammatory cells in the kidney. In conclusion, in our model, AZL and CLTD lower blood pressure and exhibit renal protective effects. Treatment with AZL offers additional protection, as evidenced by lower nephrinuria and plasma monocyte chemoattractant protein-1 levels. Combination therapy afforded the greatest protective effects and may be the best choice for hypertensive therapy in MetS. © 2014 Wiley Publishing Asia Pty Ltd.

Azilsartan medoxomil in the management of hypertension: an evidence-based review of its place in therapy.

PubMed

Angeloni, Emiliano

2016-01-01

Azilsartan (AZI) is a relatively new angiotensin receptor blocker available for the treatment of any stage of hypertension, which was eventually given in combination with chlorthalidone (CLT). To review pharmacology and clinical role of AZI monotherapy and AZI/CLT or AZI/amlodipine combination therapies for hypertension management. PubMed, Embase, and Cochrane Library were searched using search terms " azilsartan", "chlorthalidone," "pharmacology," "pharmacokinetics," "pharmacodynamics," "pharmacoeconomics," and "cost-effectiveness." To obtain other relevant information, US Food and Drug Association as well as manufacturer prescribing information were also reviewed. Randomized controlled trials demonstrated AZI to be superior to other sartans, such as valsartan, olmesartan, and candesartan, in terms of 24-hour ambulatory blood pressure monitoring (ABPM) reduction with respect. That beneficial effect of azilsartan was also associated with similar safety profiles. When compared to other antihypertensive drugs, azilsartan was found to be superior to any angiotensin-converting enzyme inhibitor, including ramipril, in terms of ABPM results, and noninferior to amlodipine in terms of sleep-BP control. The association of AZI and CLT was then found to be superior to other sartans + thiazide combination therapies in terms of both BP lowering and goal achievement. The combination of AZI and amlodipine has also been tested in clinical trials, but compared only with placebo, demonstrating its superiority in terms of efficacy and similarity in terms of safety. Azilsartan is a safe and effective treatment option for every stage of hypertension, both alone or in fixed-dose combination tablets with chlorthalidone or amlodipine. Beneficial effects of AZI were also noted in patients with any degree of renal impairment. In addition, safety profiles of AZI were similar to that of the placebo.

Effect of losartan combined with amlodipine or with a thiazide on uric acid levels in hypertensive patients.

PubMed

Rubio-Guerra, Alberto F; Garro-Almendaro, Ana K; Elizalde-Barrera, Cesar I; Suarez-Cuenca, Juan A; Duran-Salgado, Montserrat B

2017-02-01

Hyperuricemia leads to endothelial dysfunction and insulin resistance, and has been associated with diseases such as hypertension. Antihypertensive drugs modify serum uric acid levels, however, few data are available about their combinations on uricemia. In this study we evaluate the effect of two combinations of losartan, with amlodipine or with hydrochlorothiazide, on serum uric acid levels in hypertensive patients. A total of 60 hypertensive patients were randomized in two groups; group LA received losartan/amlodipine (100/5 mg) once a day, whereas LH group received losartan hydrochlorothiazide (100/12.5 mg) once a day for 3 months. In both groups serum uric acid levels were measured at the beginning and end of the study. Patients were evaluated monthly for blood pressure (BP) and adverse events. Statistical analysis was performed with a two-way analysis of variance (ANOVA) for repeated measures. All patients experienced a significant reduction of BP to the same extent (LA 155/94 to 123/79, LH 157/92 to 124/78 mmHg, p > 0.05). In the LA group, serum uric acid decreased from 6.5 ± 1.6 to 4.6 ± 1.3 mg/ml ( p = 0.0001), whereas in the LH group there was a nonsignificant increase from 5.82 ± 1.4 to 5.85 ± 1.5 mg/ml, ( p = 0.936). When both groups were compared, we found a significant reduction ( p < 0.00013) on serum uric acid levels in the LA group. Both combinations decrease BP values to the same extent, however, LA combination showed a reduction on serum uric acid levels, which may contribute to a reduction in the metabolic risk in hypertensive patients.

Role of triple fixed combination valsartan, amlodipine and hydrochlorothiazide in controlling blood pressure

PubMed Central

Doménech, Monica; Coca, Antonio

2010-01-01

Hypertension is one of the main risk factors for the development of cardiovascular diseases and the search for new therapeutic strategies aimed at optimizing its control remains an ongoing research and clinical challenge. In recent years, there has been a marked increase in the use of combinations of antihypertensive drugs with complementary mechanisms of action, with the aims of reducing blood pressure levels more rapidly and vigorously than strategies employing monotherapy and improving treatment compliance and adhesion. Therefore, as recommended by the 2009 reappraisal of the European Society of Hypertension/European Society of Cardiology Guidelines, the use of a triple combination that combines a calcium channel blocker, an angiotensin II receptor blocker and a thiazide diuretic seems a reasonable and efficacious combination for the management of hypertensive patients with moderate, high or very high risk. This article reviews the clinical trials carried out with the fixed combination of amlodipine/valsartan/hydrochlorothiazide at the doses recommended for each drug in monotherapy. The data show that this combination achieved greater reductions in mean sitting diastolic and systolic blood pressure than amlodipine, valsartan or hydrochlorothiazide in monotherapy, with favorable pharmacodynamic and pharmacokinetic profiles. The triple combination at high single doses should be used with caution in elderly patients and those with renal or liver failure. Although the tolerability and safety of the triple combination are good, the most-frequently reported adverse effects were peripheral edema, headache and dizziness. Analytical alterations were consistent with the already-known biochemical effects of amlodipine, valsartan or hydrochlorothiazide in monotherapy. In summary, triple-therapy with amlodipine/valsartan/hydrochlorothiazide in a single pill contributes additional advantages to fixed -combinations of two drugs, achieving a greater and more rapid reduction in blood pressure levels in a safe, well-tolerated manner. PMID:20517471

Long-term Effects of Antihypertensive Drug Use and New-onset Osteoporotic Fracture in Elderly Patients: A Population-based Longitudinal Cohort Study.

PubMed

Chen, Hung-Yi; Ma, Kai-Yan; Hsieh, Pei-Ling; Liou, Yi-Sheng; Jong, Gwo-Ping

2016-12-20

Antihypertensive drugs have been linked to new-onset osteoporotic fracture (NOF), and different classes of antihypertensive drugs may alter the risk for the development of NOF; however, the classic effect of different antihypertensive drugs on the development of NOF in the elderly has not been well studied during long-term follow-up. In this study, we investigated the association between different classic antihypertensives and the development of NOF in the elderly. This was a longitudinal cohort study performed using data from claim forms submitted to the Taiwan Bureau of National Health Insurance in Central Taiwan, China including case patients with NOF aged 65-80 years from January 2002 to December 2012 and non-NOF controls. Prescriptions for antihypertensives before the index date were retrieved from a prescription database. We estimated the hazard ratios (HR s) of NOF associated with antihypertensive use. Non-NOF controls served as the reference group. A total of 128 patients with NOF were identified from among 1144 patients with hypertension during the study period. The risk of NOF after adjusting age, sex, comorbidities, and concurrent medications was higher among the users of angiotensin-converting enzyme (ACE) inhibitors (HR, 1.64; 95% confidence interval [CI], 1.01-2.66) than among nonusers. Patients who took calcium channel blockers (CCBs) (HR, 0.70; 95% CI, 0.49-0.99) were at a lower risk of developing NOF than nonusers. Loop diuretics, thiazide diuretics, angiotensin receptor blocker, beta-blocker, and alpha-blocker were not associated with the risk of NOF. Elderly with hypertension who take CCBs are at a lower risk of NOF and that the use of ACE inhibitors was associated with a significantly increased risk of developing NOF during the 11-year follow-up.

Demographic, Dietary, and Urinary Factors and 24-h Urinary Calcium Excretion

PubMed Central

Curhan, Gary C.

2009-01-01

Background and objectives: Higher urinary calcium is a risk factor for nephrolithiasis. This study delineated associations between demographic, dietary, and urinary factors and 24-h urinary calcium. Design, setting, participants, & measurements: Cross-sectional studies were conducted of 2201 stone formers (SF) and 1167 nonstone formers (NSF) in the Health Professionals Follow-up Study (men) and Nurses' Health Studies I and II (older and younger women). Results: Median urinary calcium was 182 mg/d in men, 182 mg/d in older women, and 192 mg/d in younger women. Compared with NSF, urinary calcium as a fraction of calcium intake was 33 to 38% higher in SF (P values ≤0.01). In regression analyses, participants were combined because associations with urinary calcium were similar in each cohort and in SF and NSF. After multivariate adjustment, participants in the highest quartile of calcium intake excreted 18 mg/d more urinary calcium than those in the lowest (P trend =0.01). Caffeine and family history of nephrolithiasis were positively associated, whereas urinary potassium, thiazides, gout, and age were inversely associated, with urinary calcium. After multivariate adjustment, participants in the highest quartiles of urinary magnesium, sodium, sulfate, citrate, phosphorus, and volume excreted 71 mg/d, 37 mg/d, 44 mg/d, 61 mg/d, 37 mg/d, and 24 mg/d more urinary calcium, respectively, than participants in the lowest (P values trend ≤0.01). Conclusions: Intestinal calcium absorption and/or negative calcium balance is greater in SF than NSF. Higher calcium intakes at levels typically observed in free-living individuals are associated with only small increases in urinary calcium. PMID:19820135

Successful Diabetic Control as Measured by Hemoglobin A1c is Associated with Lower Urine Risk Factors for Uric Acid Calculi.

PubMed

Maciolek, Kimberly A; Penniston, Kristina L; Jhagroo, R Allan; Best, Sara L

2018-06-13

To examine the association of glycemic control, including strict glycemic control, with 24-hour (24-h) urine risk factors for uric acid and calcium calculi. With IRB approval, we identified 183 stone formers (SFs) with 459 24-h urine collections. Hemoglobin A1c (HgbA1c) measures were obtained within 3 months of the urine collection. Collections were separated into normoglycemic (NG, HgbA1c<6.5) and hyperglycemic (HG, HgbA1c≥6.5) cohorts; 24-h urine parameters were compared. The NG cohort was further divided into patients with and without a history of diabetes type 2 (DM). Variables were analyzed using chi squared, Welch's t-test and multivariate linear regression to adjust for clustering, BMI, age, gender, thiazide and potassium citrate use. Patients in the HG group were older with higher BMI. Multivariate analysis of the total study population revealed that hyperglycemia correlated with lower pH, higher uric acid relative saturation (RS), lower brushite RS and higher citrate. NG SFs with and without a history of DM had similar risk factors for uric acid stone formation. Among NG SFs, those with DM had higher urine calcium (UCa) and calcium oxalate RS than those without DM. However, this difference may be related to other factors since neither parameter correlated with DM on multivariate regression (p>0.05). Successful glycemic control may be associated with reduced urinary risk factors for uric acid stone formation. Patients with well controlled DM had equivalent risk factors to those without DM. Glycemic control should be considered a target of the multidisciplinary medical management of stone disease.

Age-related proximal femur bone mineral loss in South Indian women: a dual energy X-ray absorptiometry study.

PubMed

Anburajan, M; Rethinasabapathi, C; Korath, M P; Ponnappa, B G; Kumar, K S; Panicker, T M; Govindan, A; Jagadeesan, G N

2001-04-01

i) To collect normative data for proximal femur bone mineral density (BMD) in South Indian women using dual energy X-ray absorptiometry (DXA) and ii) to study the rate and significance of hip bone mineral loss with advancing age in this population. Forty five women, whose age ranged from 16 to 84 years were studied. This sample was drawn randomly from general medical practice at KJ Hospital, Chennai, South India during November, 1997 to April, 1998. Of these 45 cases, 21 were pre-menopausal (mean +/- SD age = 30.9+/-8.8 years) and 24 post-menopausal (mean +/- SD age = 62.1+/-11.0 years). Subjects with secondary bone diseases were excluded. Also excluded were those taking any drugs known to affect calcium metabolism e.g., thiazide diuretics, oestrogen and calcium. Subjects were divided into seven decadal age groups from 15-24 years to 75-84 years. BMD of the right proximal femur was evaluated using a QDR-1000 DXA bone densitometer (Hologic Inc., Waltham, Massachusetts, USA). Data analysis was done with SPSS/PC statistical software package. Linear regression analysis showed significant (p < 0.001) negative correlations between all hip BMD variables at different regions of interest and patient's age. Relative to that at 30 years of age, rates of BMD loss in the neck of femur, trochanter, intertrochanter, total hip and Ward's triangle were 0.68%, 0.65%, 0.58%, 0.61% and 1.05% per annum respectively. Over the age of 65 years, the above mentioned regions BMD decreased by 0.91%, 0.84%, 0.72%, 0.78% and 1.66% per annum respectively. Normative data for proximal femur BMD in South India women have been evaluated and it may prove useful for diagnosing osteoporosis in the women of South India.

The 2009 Canadian Hypertension Education Program recommendations for the management of hypertension: Part 2--therapy.

PubMed

Khan, Nadia A; Hemmelgarn, Brenda; Herman, Robert J; Bell, Chaim M; Mahon, Jeff L; Leiter, Lawrence A; Rabkin, Simon W; Hill, Michael D; Padwal, Raj; Touyz, Rhian M; Larochelle, Pierre; Feldman, Ross D; Schiffrin, Ernesto L; Campbell, Norman R C; Moe, Gordon; Prasad, Ramesh; Arnold, Malcolm O; Campbell, Tavis S; Milot, Alain; Stone, James A; Jones, Charlotte; Ogilvie, Richard I; Hamet, Pavel; Fodor, George; Carruthers, George; Burns, Kevin D; Ruzicka, Marcel; DeChamplain, Jacques; Pylypchuk, George; Petrella, Robert; Boulanger, Jean-Martin; Trudeau, Luc; Hegele, Robert A; Woo, Vincent; McFarlane, Phil; Vallée, Michel; Howlett, Jonathan; Bacon, Simon L; Lindsay, Patrice; Gilbert, Richard E; Lewanczuk, Richard Z; Tobe, Sheldon

2009-05-01

To update the evidence-based recommendations for the prevention and management of hypertension in adults for 2009. For lifestyle and pharmacological interventions, evidence from randomized controlled trials and systematic reviews of trials was preferentially reviewed. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. However, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the lack of long-term morbidity and mortality data in this field. Progression of kidney dysfunction was also accepted as a clinically relevant primary outcome among patients with chronic kidney disease. A Cochrane collaboration librarian conducted an independent MEDLINE search from 2007 to August 2008 to update the 2008 recommendations. To identify additional published studies, reference lists were reviewed and experts were contacted. All relevant articles were reviewed and appraised independently by both content and methodological experts using prespecified levels of evidence. For lifestyle modifications to prevent and treat hypertension, restrict dietary sodium to less than 2300 mg (100 mmol)/day (and 1500 mg to 2300 mg [65 mmol to 100 mmol]/day in hypertensive patients); perform 30 min to 60 min of aerobic exercise four to seven days per week; maintain a healthy body weight (body mass index 18.5 kg/m(2) to 24.9 kg/m(2)) and waist circumference (smaller than 102 cm for men and smaller than 88 cm for women); limit alcohol consumption to no more than 14 units per week in men or nine units per week in women; follow a diet that is reduced in saturated fat and cholesterol, and that emphasizes fruits, vegetables and low-fat dairy products, dietary and soluble fibre, whole grains and protein from plant sources; and consider stress management in selected individuals with hypertension. For the pharmacological management of hypertension, treatment thresholds and targets should be predicated on by the patient's global atherosclerotic risk, target organ damage and comorbid conditions. Blood pressure should be decreased to lower than 140/90 mmHg in all patients, and to lower than 130/80 mmHg in those with diabetes mellitus or chronic kidney disease. Most patients will require more than one agent to achieve these target blood pressures. Antihypertensive therapy should be considered in all adult patients regardless of age (caution should be exercised in elderly patients who are frail). For adults without compelling indications for other agents, initial therapy should include thiazide diuretics. Other agents appropriate for first-line therapy for diastolic and/or systolic hypertension include angiotensin- converting enzyme (ACE) inhibitors (in patients who are not black), long-acting calcium channel blockers (CCBs), angiotensin receptor antagonists (ARBs) or beta-blockers (in those younger than 60 years of age). A combination of two first-line agents may also be considered as the initial treatment of hypertension if the systolic blood pressure is 20 mmHg above the target or if the diastolic blood pressure is 10 mmHg above the target. The combination of ACE inhibitors and ARBs should not be used. Other agents appropriate for first-line therapy for isolated systolic hypertension include long- acting dihydropyridine CCBs or ARBs. In patients with angina, recent myocardial infarction or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with cerebrovascular disease, an ACE inhibitor/diuretic combination is preferred; in patients with proteinuric nondiabetic chronic kidney disease, ACE inhibitors or ARBs (if intolerant to ACE inhibitors) are recommended; and in patients with diabetes mellitus, ACE inhibitors or ARBs (or, in patients without albuminuria, thiazides or dihydropyridine CCBs) are appropriate first-line therapies. All hypertensive patients with dyslipidemia should be treated using the thresholds, targets and agents outlined in the Canadian Cardiovascular Society position statement (recommendations for the diagnosis and treatment of dyslipidemia and prevention of cardiovascular disease). Selected high-risk patients with hypertension who do not achieve thresholds for statin therapy according to the position paper should nonetheless receive statin therapy. Once blood pressure is controlled, acetylsalicylic acid therapy should be considered. All recommendations were graded according to strength of the evidence and voted on by the 57 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

The 2007 Canadian Hypertension Education Program recommendations for the management of hypertension: part 2 - therapy.

PubMed

Khan, Nadia A; Hemmelgarn, Brenda; Padwal, Raj; Larochelle, Pierre; Mahon, Jeff L; Lewanczuk, Richard Z; McAlister, Finlay A; Rabkin, Simon W; Hill, Michael D; Feldman, Ross D; Schiffrin, Ernesto L; Campbell, Norman R C; Logan, Alexander G; Arnold, Malcolm; Moe, Gordon; Campbell, Tavis S; Milot, Alain; Stone, James A; Jones, Charlotte; Leiter, Lawrence A; Ogilvie, Richard I; Herman, Robert J; Hamet, Pavel; Fodor, George; Carruthers, George; Culleton, Bruce; Burns, Kevin D; Ruzicka, Marcel; deChamplain, Jacques; Pylypchuk, George; Gledhill, Norm; Petrella, Robert; Boulanger, Jean-Martin; Trudeau, Luc; Hegele, Robert A; Woo, Vincent; McFarlane, Phil; Touyz, Rhian M; Tobe, Sheldon W

2007-05-15

To provide updated, evidence-based recommendations for the prevention and management of hypertension in adults. For lifestyle and pharmacological interventions, evidence was reviewed from randomized controlled trials and systematic reviews of trials. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. However, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the lack of long-term morbidity and mortality data in this field. For treatment of patients with kidney disease, the progression of kidney dysfunction was also accepted as a clinically relevant primary outcome. A Cochrane collaboration librarian conducted an independent MEDLINE search from 2005 to August 2006 to update the 2006 Canadian Hypertension Education Program recommendations. In addition, reference lists were scanned and experts were contacted to identify additional published studies. All relevant articles were reviewed and appraised independently by both content and methodological experts using prespecified levels of evidence. Dietary lifestyle modifications for prevention of hypertension, in addition to a well-balanced diet, include a dietary sodium intake of less than 100 mmol/day. In hypertensive patients, the dietary sodium intake should be limited to 65 mmol/day to 100 mmol/day. Other lifestyle modifications for both normotensive and hypertensive patients include: performing 30 min to 60 min of aerobic exercise four to seven days per week; maintaining a healthy body weight (body mass index of 18.5 kg/m2 to 24.9 kg/m2) and waist circumference (less than 102 cm in men and less than 88 cm in women); limiting alcohol consumption to no more than 14 units per week in men or nine units per week in women; following a diet reduced in saturated fat and cholesterol, and one that emphasizes fruits, vegetables and low-fat dairy products, dietary and soluble fibre, whole grains and protein from plant sources; and considering stress management in selected individuals with hypertension. For the pharmacological management of hypertension, treatment thresholds and targets should take into account each individual's global atherosclerotic risk, target organ damage and any comorbid conditions: blood pressure should be lowered to lower than 140/90 mmHg in all patients and lower than 130/80 mmHg in those with diabetes mellitus or chronic kidney disease. Most patients require more than one agent to achieve these blood pressure targets. In adults without compelling indications for other agents, initial therapy should include thiazide diuretics; other agents appropriate for first-line therapy for diastolic and/or systolic hypertension include angiotensin-converting enzyme (ACE) inhibitors (except in black patients), long-acting calcium channel blockers (CCBs), angiotensin receptor blockers (ARBs) or beta-blockers (in those younger than 60 years of age). First-line therapy for isolated systolic hypertension includes long-acting dihydropyridine CCBs or ARBs. Certain comorbid conditions provide compelling indications for first-line use of other agents: in patients with angina, recent myocardial infarction, or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with cerebrovascular disease, an ACE inhibitor plus diuretic combination is preferred; in patients with nondiabetic chronic kidney disease, ACE inhibitors are recommended; and in patients with diabetes mellitus, ACE inhibitors or ARBs (or, in patients without albuminuria, thiazides or dihydropyridine CCBs) are appropriate first-line therapies. All hypertensive patients with dyslipidemia should be treated using the thresholds, targets and agents outlined in the Canadian Cardiovascular Society position statement (recommendations for the diagnosis and treatment of dyslipidemia and prevention of cardiovascular disease). Selected high-risk patients with hypertension who do not achieve thresholds for statin therapy according to the position paper should nonetheless receive statin therapy. Once blood pressure is controlled, acetylsalicylic acid therapy should be considered. All recommendations were graded according to strength of the evidence and voted on by the 57 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

Benazepril plus amlodipine or hydrochlorothiazide for hypertension in high-risk patients.

PubMed

Jamerson, Kenneth; Weber, Michael A; Bakris, George L; Dahlöf, Björn; Pitt, Bertram; Shi, Victor; Hester, Allen; Gupte, Jitendra; Gatlin, Marjorie; Velazquez, Eric J

2008-12-04

The optimal combination drug therapy for hypertension is not established, although current U.S. guidelines recommend inclusion of a diuretic. We hypothesized that treatment with the combination of an angiotensin-converting-enzyme (ACE) inhibitor and a dihydropyridine calcium-channel blocker would be more effective in reducing the rate of cardiovascular events than treatment with an ACE inhibitor plus a thiazide diuretic. In a randomized, double-blind trial, we assigned 11,506 patients with hypertension who were at high risk for cardiovascular events to receive treatment with either benazepril plus amlodipine or benazepril plus hydrochlorothiazide. The primary end point was the composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, hospitalization for angina, resuscitation after sudden cardiac arrest, and coronary revascularization. The baseline characteristics of the two groups were similar. The trial was terminated early after a mean follow-up of 36 months, when the boundary of the prespecified stopping rule was exceeded. Mean blood pressures after dose adjustment were 131.6/73.3 mm Hg in the benazepril-amlodipine group and 132.5/74.4 mm Hg in the benazepril-hydrochlorothiazide group. There were 552 primary-outcome events in the benazepril-amlodipine group (9.6%) and 679 in the benazepril-hydrochlorothiazide group (11.8%), representing an absolute risk reduction with benazepril-amlodipine therapy of 2.2% and a relative risk reduction of 19.6% (hazard ratio, 0.80, 95% confidence interval [CI], 0.72 to 0.90; P<0.001). For the secondary end point of death from cardiovascular causes, nonfatal myocardial infarction, and nonfatal stroke, the hazard ratio was 0.79 (95% CI, 0.67 to 0.92; P=0.002). Rates of adverse events were consistent with those observed from clinical experience with the study drugs. The benazepril-amlodipine combination was superior to the benazepril-hydrochlorothiazide combination in reducing cardiovascular events in patients with hypertension who were at high risk for such events. (ClinicalTrials.gov number, NCT00170950.) 2008 Massachusetts Medical Society

Refractory Hypertension Is not Attributable to Intravascular Fluid Retention as Determined by Intracardiac Volumes.

PubMed

Velasco, Alejandro; Siddiqui, Mohammed; Kreps, Eric; Kolakalapudi, Pavani; Dudenbostel, Tanja; Arora, Garima; Judd, Eric K; Prabhu, Sumanth D; Lloyd, Steven G; Oparil, Suzanne; Calhoun, David A

2018-06-04

Refractory hypertension (RfHTN) is an extreme phenotype of antihypertensive treatment failure defined as lack of blood pressure control with ≥5 medications, including a long-acting thiazide and a mineralocorticoid receptor antagonist. RfHTN is a subgroup of resistant hypertension (RHTN), which is defined as blood pressure >135/85 mm Hg with ≥3 antihypertensive medications, including a diuretic. RHTN is generally attributed to persistent intravascular fluid retention. It is unknown whether alternative mechanisms are operative in RfHTN. Our objective was to determine whether RfHTN is characterized by persistent fluid retention, indexed by greater intracardiac volumes determined by cardiac magnetic resonance when compared with controlled RHTN patients. Consecutive patients evaluated in our institution with RfHTN and controlled RHTN were prospectively enrolled. Exclusion criteria included advanced chronic kidney disease and masked or white coat hypertension. All enrolled patients underwent biochemical testing and cardiac magnetic resonance. The RfHTN group (n=24) was younger (mean age, 51.7±8.9 versus 60.6±11.5 years; P =0.003) and had a greater proportion of women (75.0% versus 43%; P =0.02) compared with the controlled RHTN group (n=30). RfHTN patients had a greater left ventricular mass index (88.3±35.0 versus 54.6±12.5 g/m 2 ; P <0.001), posterior wall thickness (10.1±3.1 versus 7.7±1.5 mm; P =0.001), and septal wall thickness (14.5±3.8 versus 10.0±2.2 mm; P <0.001). There was no difference in B-type natriuretic peptide levels and left atrial or ventricular volumes. Diastolic dysfunction was noted in RfHTN. Our findings demonstrate greater left ventricular hypertrophy without chamber enlargement in RfHTN, suggesting that antihypertensive treatment failure is not attributable to intravascular volume retention. © 2018 American Heart Association, Inc.

Effect of diuretics on fetal growth: A drug effect or confounding by indication? Pooled Danish and Scottish cohort data

PubMed Central

Olesen, Charlotte; de Vries, Corinne S; Thrane, Nana; MacDonald, Tom M; Larsen, Helle; Sørensen, Henrik Toft

2001-01-01

Aims The diabetogenic effect of diuretics, as well as the indication for prescribing them, may impact on fetal growth. We analysed whether the purchase of prescription drugs for diuretics during pregnancy was associated with measures of fetal growth. Methods During 1991–98 all women who purchased prescription drugs for diuretics during pregnancy were identified in the Northern Jutland Prescription Database (NJDP), Denmark, and in the Medicines Monitoring Unit's Database (MEMO), Scotland. Information on birth weight and gestational age was obtained from the Danish Birth Registry, the Danish Hospital Discharge Registry and the Scottish Tayside Neonatal Database. Information on diabetes, hypertension and prepregnancy weight were obtained by hospital record review in a sample of women in the Danish cohort. Women who did not purchase prescription diuretics during pregnancy were used as a reference group in both cohorts. Results Danish women who purchased prescription loop diuretics during pregnancy gave birth to infants with higher birth weights than women who did not use diuretics; mean difference 104.7 g (95% CI; 2.6, 206.9). However, the high prevalence of diabetes (10.3%) among Danish women who purchased prescription loop diuretics during pregnancy might explain this result. Both the Danish and the Scottish women who purchased prescription diuretics during their pregnancy were at increased risk of preterm delivery (< 37 completed weeks); ORs: 1.8 (CI; 1.2, 2.7)NJDP, 1.9 (CI; 0.9, 4.3)MEMO. The proportion of hypertension among women who purchased prescription thiazides was 15.8%, and the risk of having an infant with a birth weight (BW) < 2500 g was increased; ORs: 2.6 (CI; 1.4, 5.0)NJDP, 2.4 (CI; 0.8, 7.8)MEMO. Conclusions Prescribing diuretics during pregnancy was associated with differences in birth weight and incidence of preterm delivery. Confounding by indication may explain the findings. PMID:11259987

Exploratory analysis of osteoarthritis progression among medication users: data from the Osteoarthritis Initiative.

PubMed

Driban, Jeffrey B; Lo, Grace H; Eaton, Charles B; Lapane, Kate L; Nevitt, Michael; Harvey, William F; McCulloch, Charles E; McAlindon, Timothy E

2016-12-01

We conducted an exploratory analysis of osteoarthritis progression among medication users in the Osteoarthritis Initiative to identify interventions or pathways that may be associated with disease modification and therefore of interest for future clinical trials. We used participants from the Osteoarthritis Initiative with annual medication inventory data between the baseline and 36-month follow-up visit ( n = 2938). Consistent medication users were defined for each medication classification as a participant reporting at all four annual visits that they were regularly using an oral prescription medication at the time of the visit. The exploratory analysis focused on medication classes with 40 or more users. The primary outcome measures were medial tibiofemoral joint space width change and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) knee pain score change (12-36-month visits). Within each knee, we explored eight comparisons between users and matched or unmatched nonusers (defined two ways). An effect size of each comparison was calculated. Medication classes had potential signals if (a) both knees had less progression among users compared with nonusers, or (b) there was less progression based on structure and symptoms in one knee. We screened 28 medication classes. Six medication classes had signals for fewer structural changes and better knee pain changes: alpha-adrenergic blockers, antilipemic (excluding statins and fibric acid), anticoagulants, selective serotonin reuptake inhibitors, antihistamines, and antineoplastic agents. Four medication classes had signals for structural changes alone: anti-estrogen (median effect size = 0.28; range = -0.41-0.64), angiotensin-converting enzyme inhibitors (median effect size = 0.13; range = -0.08-0.28), beta-adrenergic blockers (median effect size = 0.09; range = 0.01-0.30), and thyroid agents (median effect size = 0.04; range = -0.05-0.14). Thiazide diuretics had evidence for symptom modification (median effect size = -0.12; range = -0.24-0.04). Users of neurovascular, antilipemic, or hormonal interventions may have less disease progression compared with nonusers.

Efficacy of Hydrochlorothiazide and low renal solute feed in Neonatal Central Diabetes Insipidus with transition to Oral Desmopressin in early infancy.

PubMed

Abraham, Mary B; Rao, Shripada; Price, Glynis; Choong, Catherine S

2014-01-01

The treatment of central diabetes insipidus (DI) with desmopressin in the neonatal period is challenging because of the significant risk of hyponatremia with this agent. The fixed anti-diuresis action of desmopressin and the obligate high fluid intake with milk feeds lead to considerable risk of water intoxication and hyponatremia. To reduce this risk, thiazide diuretics, part of the treatment of nephrogenic DI, were used in conjunction with low renal solute feed and were effective in a single case series of neonatal central DI. We evaluated the efficacy of early treatment of neonatal central DI with hydrochlorothiazide with low solute feed and investigated the clinical indicators for transition to desmopressin during infancy. A retrospective chart review was conducted at Princess Margaret Hospital, Perth of neonates diagnosed with central DI and treated with hydrochlorothiazide, between 2007 and 2013. Four newborns were identified. Mean sNa and mean change in sNa with desmopressin and hydrochlorothiazide treatment were recorded along with episodes of hyponatremia and hypernatremia. Length and weight trajectories during the first 12 months were assessed. The mean change in sNa per day with hydrochlorothiazide and low renal solute feed was 2.5 - 3 mmol/L; on desmopressin treatment, the mean change in sNa was 6.8-7.9 mmol/L. There was one episode of symptomatic hyponatremia with intranasal desmopressin with no episodes of hyponatremia or hypernatremia during treatment with hydrochlorothiazide or following transition to oral desmopressin. Transition to oral desmopressin between 3 to 12 months of age was associated with good control of DI. Following introduction of solids, sNa remained stable but weight gain was slow. This improved following transition to desmopressin in one infant. Hydrochlorothiazide with low renal solute feed is a safe and effective treatment option in neonatal central DI. However, transition to desmopressin should be considered early in infancy following initiation of solids to facilitate growth.

Antihypertensive Medications and the Prevalence of Hyperkalemia in a Large Health System.

PubMed

Chang, Alex R; Sang, Yingying; Leddy, Julia; Yahya, Taher; Kirchner, H Lester; Inker, Lesley A; Matsushita, Kunihiro; Ballew, Shoshana H; Coresh, Josef; Grams, Morgan E

2016-06-01

Little is known about the frequency and patterns of hyperkalemia in clinical settings. We evaluated the association between baseline antihypertensive medications that may affect potassium levels (angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, loop/thiazide diuretics, and potassium-sparing diuretics) and hyperkalemia, defined by potassium >5 mEq/L and >5.5 mEq/L, over a 3-year time period in 194 456 outpatients in the Geisinger Health System, as well as actions taken after an episode of hyperkalemia. The proportions of patients with 0, <2, 2 to 4, and ≥4 potassium measurements per year were 20%, 58%, 16%, and 6%. Potassium levels >5 mEq/L and >5.5 mEq/L occurred in 10.8% and 2.3% of all patients over the 3-year period; among patients with ≥4 measurements per year, corresponding values were 39.4% and 14.6%. Most cases of hyperkalemia occurred only once during follow-up. The antihypertensive medication class most strongly associated with hyperkalemia was angiotensin-converting enzyme inhibitors. Among patients with a measurement of potassium >5.5 mEq/L, only 24% were seen by a nephrologist and 5.2% were seen by a dietician during the 3-year period. Short-term actions after a potassium measurement >5.5 mEq/L included emergency room visit (3.1% within 7 days), remeasurement of potassium (44.3% with 14 days), and change in a potassium-altering medication (26.4% within 60 days). The most common medication changes were discontinuation/dose reduction of an angiotensin-converting enzyme inhibitor/angiotensin receptor blocker or potassium-sparing diuretic, which occurred in 29.1% and 49.6% of people taking these medications, respectively. In conclusion, hyperkalemia is common. Future research may enable optimal renin-angiotensin-aldosterone system inhibitor use with improved management of hyperkalemia. © 2016 American Heart Association, Inc.

The National Action Plan for the Prevention and Control of Non-communicable Diseases and Health Promotion in Pakistan--Cardiovascular diseases.

PubMed

Nishtar, Sania; Faruqui, Azhar M A; Mattu, Mohamad A; Mohamud, Khalif Bile; Ahmed, Ashfaq

2004-12-01

The National Action Plan for Non-Communicable Disease Prevention, Control and Health Promotion in Pakistan (NAP-NCD) incorporates prevention and control of cardiovascular diseases (CVD) as part of a comprehensive and integrated non-communicable Disease (NCD) prevention effort. In this programme, surveillance of cardiovascular risk factors is part of an integrated population-based NCD surveillance system. The population approach to CVD prevention is a priority area in this programme with a focus on broad policy measures and behavioural change communication. The former include revision of the current policy on diet and nutrition to expand its focus on under-nutrition; the development of a physical activity policy; strategies to limit the production of, and access to, ghee as a medium for cooking and agricultural and fiscal policies that increase the demand for, and make healthy food more accessible. The programme focuses attention on improving the quality of prevention programmes within primary and basic health sites and integrates concerted primary and secondary prevention programmes into health services as part of a comprehensive and sustainable, scientifically valid, and resource-sensitive programme for all categories of healthcare providers. It promotes screening for raised blood pressure at the population level and screening for dyslipidaemia and diabetes in high-risk groups only. It highlights the need to ensure the availability of aspirin, beta blockers, thiazides, ACE inhibitors, statins and penicillin at all levels of healthcare. The programme points out the need to conduct clinical end-point trials in the native Pakistani setting to define cost-effective therapeutic strategies for primary and secondary prevention of CVDs. Emphasis is laid on building capacity of health systems in support of CVD prevention and control and building a coalition or network of organizations to add momentum to CVD prevention and control efforts.

Drug-Induced Hyperglycaemia and Diabetes.

PubMed

Fathallah, Neila; Slim, Raoudha; Larif, Sofien; Hmouda, Houssem; Ben Salem, Chaker

2015-12-01

Drug-induced hyperglycaemia and diabetes is a global issue. It may be a serious problem, as it increases the risk of microvascular and macrovascular complications, infections, metabolic coma and even death. Drugs may induce hyperglycaemia through a variety of mechanisms, including alterations in insulin secretion and sensitivity, direct cytotoxic effects on pancreatic cells and increases in glucose production. Antihypertensive drugs are not equally implicated in increasing serum glucose levels. Glycaemic adverse events occur more frequently with thiazide diuretics and with certain beta-blocking agents than with calcium-channel blockers and inhibitors of the renin-angiotensin system. Lipid-modifying agents may also induce hyperglycaemia, and the diabetogenic effect seems to differ between the different types and daily doses of statins. Nicotinic acid may also alter glycaemic control. Among the anti-infectives, severe life-threatening events have been reported with fluoroquinolones, especially when high doses are used. Protease inhibitors and, to a lesser extent, nucleoside reverse transcriptase inhibitors have been reported to induce alterations in glucose metabolism. Pentamidine-induced hyperglycaemia seems to be related to direct dysfunction in pancreatic cells. Phenytoin and valproic acid may also induce hyperglycaemia. The mechanisms of second-generation antipsychotic-associated hyperglycaemia, diabetes mellitus and ketoacidosis are complex and are mainly due to insulin resistance. Antidepressant agents with high daily doses seem to be more frequently associated with an increased risk of diabetes. Ketoacidosis may occur in patients receiving beta-adrenergic stimulants, and theophylline may also induce hyperglycaemia. Steroid diabetes is more frequently associated with high doses of glucocorticoids. Some chemotherapeutic agents carry a higher risk of hyperglycaemia, and calcineurin inhibitor-induced hyperglycaemia is mainly due to a decrease in insulin secretion. Hyperglycaemia has been associated with oral contraceptives containing high doses of oestrogen. Growth hormone therapy and somatostatin analogues may also induce hyperglycaemia. Clinicians should be aware of medications that may alter glycaemia. Efforts should be made to identify and closely monitor patients receiving drugs that are known to induce hyperglycaemia.

Full-dose Perindopril/Indapamide in the Treatment of Difficult-to-Control Hypertension: The FORTISSIMO Study.

PubMed

Karpov, Yuri Aleksandrovich

2017-02-01

Blood pressure (BP) control in hypertensive patients remains poor worldwide, particularly in high-risk patients with hypertension and diabetes. Guidelines recommend that such patients receive prompt pharmacological therapy at maximal doses to rapidly control BP. We aimed to evaluate efficacy and safety of single-pill combination (SPC) perindopril/indapamide (PER/IND) at full dose (10/2.5 mg) in hypertensive patients, including diabetics, with BP uncontrolled by previous medication. Twelve-week prospective, observational study in patients with uncontrolled hypertension (≥160-200 mmHg systolic BP [SBP] and <110 mmHg diastolic BP [DBP]) on a previous SPC or free-dose combination of renin-angiotensin system blocker plus thiazide diuretic, substituted with PER/IND 10/2.5 mg. Office BP, quality of life, and blood parameters were evaluated in the whole cohort and patients with type 2 diabetes mellitus. 2120 ambulatory hypertensive patients were enrolled, including 307 with type 2 diabetes. Two weeks after substitution, SBP significantly decreased from 171.0 ± 13.3 to 148.6 ± 13.4 mmHg, and DBP from 98.6 ± 8.3 to 88.8 ± 7.9 mmHg (both p < 0.00001). A similar rapid decrease was noted in the diabetes subgroup. After 12 weeks, BP had reduced by 42/19 mmHg in the whole cohort (diabetes subgroup: 41/18 mmHg). Most (84%; diabetes subgroup: 77%) patients reached BP target (<140/90 mmHg). Laboratory tests and quality of life improved in the whole cohort and the diabetic subgroup. Switching to PER/IND at full dose (10/2.5 mg) was well tolerated, leading to fast BP reduction and control in the majority of patients with uncontrolled hypertension, including difficult-to-treat patients with diabetes.

A strategy to reduce cardiovascular disease by more than 80%

PubMed Central

Wald, N J; Law, M R

2003-01-01

Objectives To determine the combination of drugs and vitamins, and their doses, for use in a single daily pill to achieve a large effect in preventing cardiovascular disease with minimal adverse effects. The strategy was to simultaneously reduce four cardiovascular risk factors (low density lipoprotein cholesterol, blood pressure, serum homocysteine, and platelet function) regardless of pretreatment levels. Design We quantified the efficacy and adverse effects of the proposed formulation from published meta-analyses of randomised trials and cohort studies and a meta-analysis of 15 trials of low dose (50-125 mg/day) aspirin. Outcome measures Proportional reduction in ischaemic heart disease (IHD) events and strokes; life years gained; and prevalence of adverse effects. Results The formulation which met our objectives was: a statin (for example, atorvastatin (daily dose 10 mg) or simvastatin (40 mg)); three blood pressure lowering drugs (for example, a thiazide, a β blocker, and an angiotensin converting enzyme inhibitor), each at half standard dose; folic acid (0.8 mg); and aspirin (75 mg). We estimate that the combination (which we call the Polypill) reduces IHD events by 88% (95% confidence interval 84% to 91%) and stroke by 80% (71% to 87%). One third of people taking this pill from age 55 would benefit, gaining on average about 11 years of life free from an IHD event or stroke. Summing the adverse effects of the components observed in randomised trials shows that the Polypill would cause symptoms in 8-15% of people (depending on the precise formulation). Conclusion The Polypill strategy could largely prevent heart attacks and stroke if taken by everyone aged 55 and older and everyone with existing cardiovascular disease. It would be acceptably safe and with widespread use would have a greater impact on the prevention of disease in the Western world than any other single intervention. PMID:12829553

Esophageal desalination is mediated by Na⁺, H⁺ exchanger-2 in the gulf toadfish (Opsanus beta).

PubMed

Esbaugh, Andrew J; Grosell, Martin

2014-05-01

Esophageal desalination is a crucial step in the gastrointestinal water absorption pathway, as this pre-intestinal processing establishes the osmotic conditions necessary for water absorption. Previous work has shown that esophageal Na(+) absorption is amiloride sensitive; however, it is as yet unclear if Na(+), H(+) exchangers (NHE) or Na(+) channels (ENaC) are responsible. The purpose of the current study was therefore to investigate the roles that NHE isoforms may play in this process in a marine teleost, the gulf toadfish (Opsanus beta), as well as what role NHE isoforms may play in the downstream intestinal Na(+) transport. A combination of symmetrical current clamp and asymmetrical voltage clamp experiments showed the esophagus to contain both an ion absorptive current (I(sc)=0.83±0.68) and serosal side negative transepithelial potential (TEP=-4.9±0.6). (22)Na uptake (J(Na)(m→s)) was inhibited by 0.5 mM EIPA, with no effect of 0.1 mM amiloride, 1 mM furosemide or 1 mM thiazide. A Cl(-) free saline reduced J(Na)(m→s) by 40% while also reducing conductance and reversing TEP. These results suggest that both transcellular and paracellular components contribute to esophageal Na(+) transport, with transcellular transport mediated by NHE. The NHE1, NHE2 and NHE3 genes were amplified and tissue distribution analysis by real-time PCR showed high NHE2 expression levels in the esophagus and stomach. Little NHE3 expression was observed throughout the gastrointestinal tract, and NHE2 expression was absent from the intestine. Hypersalinity (60 ppt) had no effect on the expression profile of NHE2, slc4a2, scl26a6, CAc or V-type ATPase (β-subunit), suggesting that esophageal desalination is less flexible in response to osmotic stress than the intestine. Copyright © 2014 Elsevier Inc. All rights reserved.

Expression of renal distal tubule transporters TRPM6 and NCC in a rat model of cyclosporine nephrotoxicity and effect of EGF treatment.

PubMed

Ledeganck, Kristien J; Boulet, Gaëlle A; Horvath, Caroline A; Vinckx, Marleen; Bogers, Johannes J; Van Den Bossche, Rita; Verpooten, Gert A; De Winter, Benedicte Y

2011-09-01

Renal magnesium (Mg(2+)) and sodium (Na(+)) loss are well-known side effects of cyclosporine (CsA) treatment in humans, but the underlying mechanisms still remain unclear. Recently, it was shown that epidermal growth factor (EGF) stimulates Mg(2+) reabsorption in the distal convoluted tubule (DCT) via TRPM6 (Thébault S, Alexander RT, Tiel Groenestege WM, Hoenderop JG, Bindels RJ. J Am Soc Nephrol 20: 78-85, 2009). In the DCT, the final adjustment of renal sodium excretion is regulated by the thiazide-sensitive Na(+)-Cl(-) cotransporter (NCC), which is activated by the renin-angiotensin-aldosterone system (RAAS). The aim of this study was to gain more insight into the molecular mechanisms of CsA-induced hypomagnesemia and hyponatremia. Therefore, the renal expression of TRPM6, TRPM7, EGF, EGF receptor, claudin-16, claudin-19, and the NCC, and the effect of the RAAS on NCC expression, were analyzed in vivo in a rat model of CsA nephrotoxicity. Also, the effect of EGF administration on these parameters was studied. CsA significantly decreased the renal expression of TRPM6, TRPM7, NCC, and EGF, but not that of claudin-16 and claudin-19. Serum aldosterone was significantly lower in CsA-treated rats. In control rats treated with EGF, an increased renal expression of TRPM6 together with a decreased fractional excretion of Mg(2+) (FE Mg(2+)) was demonstrated. EGF did not show this beneficial effect on TRPM6 and FE Mg(2+) in CsA-treated rats. These data suggest that CsA treatment affects Mg(2+) homeostasis via the downregulation of TRPM6 in the DCT. Furthermore, CsA downregulates the NCC in the DCT, associated with an inactivation of the RAAS, resulting in renal sodium loss.

Paradoxical activation of the sodium chloride cotransporter (NCC) without hypertension in kidney deficient in a regulatory subunit of Na,K-ATPase, FXYD2.

PubMed

Arystarkhova, Elena; Ralph, Donna L; Liu, Yi Bessie; Bouley, Richard; McDonough, Alicia A; Sweadner, Kathleen J

2014-12-01

Na,K-ATPase generates the driving force for sodium reabsorption in the kidney. Na,K-ATPase functional properties are regulated by small proteins belonging to the FXYD family. In kidney FXYD2 is the most abundant: it is an inhibitory subunit expressed in almost every nephron segment. Its absence should increase sodium pump activity and promote Na(+) retention, however, no obvious renal phenotype was detected in mice with global deletion of FXYD2 (Arystarkhova et al. 2013). Here, increased total cortical Na,K-ATPase activity was documented in the Fxyd2(-/-) mouse, without increased α1β1 subunit expression. We tested the hypothesis that adaptations occur in distal convoluted tubule (DCT), a major site of sodium adjustments. Na,K-ATPase immunoreactivity in DCT was unchanged, and there was no DCT hypoplasia. There was a marked activation of thiazide-sensitive sodium chloride cotransporter (NCC; Slc12a3) in DCT, predicted to increase Na(+) reabsorption in this segment. Specifically, NCC total increased 30% and NCC phosphorylated at T53 and S71, associated with activation, increased 4-6 fold. The phosphorylation of the closely related thick ascending limb (TAL) apical NKCC2 (Slc12a1) increased at least twofold. Abundance of the total and cleaved (activated) forms of ENaC α-subunit was not different between genotypes. Nonetheless, no elevation of blood pressure was evident despite the fact that NCC and NKCC2 are in states permissive for Na(+) retention. Activation of NCC and NKCC2 may reflect an intracellular linkage to elevated Na,K-ATPase activity or a compensatory response to Na(+) loss proximal to the TAL and DCT. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

AT2R (Angiotensin II Type 2 Receptor)-Mediated Regulation of NCC (Na-Cl Cotransporter) and Renal K Excretion Depends on the K Channel, Kir4.1.

PubMed

Wu, Peng; Gao, Zhong-Xiuzi; Duan, Xin-Peng; Su, Xiao-Tong; Wang, Ming-Xiao; Lin, Dao-Hong; Gu, Ruimin; Wang, Wen-Hui

2018-04-01

AT2R (AngII [angiotensin II] type 2 receptor) is expressed in the distal nephrons. The aim of the present study is to examine whether AT2R regulates NCC (Na-Cl cotransporter) and Kir4.1 of the distal convoluted tubule. AngII inhibited the basolateral 40 pS K channel (a Kir4.1/5.1 heterotetramer) in the distal convoluted tubule treated with losartan but not with PD123319. AT2R agonist also inhibits the K channel, indicating that AT2R was involved in tonic regulation of Kir4.1. The infusion of PD123319 stimulated the expression of tNCC (total NCC) and pNCC (phosphorylated NCC; Thr 53 ) by a time-dependent way with the peak at 4 days. PD123319 treatment (4 days) stimulated the basolateral 40 pS K channel activity, augmented the basolateral K conductance, and increased the negativity of distal convoluted tubule membrane. The stimulation of Kir4.1 was essential for PD123319-induced increase in NCC because inhibiting AT2R increased the expression of tNCC and pNCC only in wild-type but not in the kidney-specific Kir4.1 knockout mice. Renal clearance study showed that thiazide-induced natriuretic effect was larger in PD123319-treated mice for 4 days than untreated mice. However, this effect was absent in kidney-specific Kir4.1 knockout mice which were also Na wasting under basal conditions. Finally, application of AT2R antagonist decreased the renal ability of K excretion and caused hyperkalemia in wild-type but not in kidney-specific Kir4.1 knockout mice. We conclude that AT2R-dependent regulation of NCC requires Kir4.1 in the distal convoluted tubule and that AT2R plays a role in stimulating K excretion by inhibiting Kir4.1 and NCC. © 2018 American Heart Association, Inc.

Phosphatidylinositol 3-kinase/Akt signaling pathway activates the WNK-OSR1/SPAK-NCC phosphorylation cascade in hyperinsulinemic db/db mice.

PubMed

Nishida, Hidenori; Sohara, Eisei; Nomura, Naohiro; Chiga, Motoko; Alessi, Dario R; Rai, Tatemitsu; Sasaki, Sei; Uchida, Shinichi

2012-10-01

Metabolic syndrome patients have insulin resistance, which causes hyperinsulinemia, which in turn causes aberrant increased renal sodium reabsorption. The precise mechanisms underlying this greater salt sensitivity of hyperinsulinemic patients remain unclear. Abnormal activation of the recently identified with-no-lysine kinase (WNK)-oxidative stress-responsive kinase 1 (OSR1)/STE20/SPS1-related proline/alanine-rich kinase (SPAK)-NaCl cotransporter (NCC) phosphorylation cascade results in the salt-sensitive hypertension of pseudohypoaldosteronism type II. Here, we report a study of renal WNK-OSR1/SPAK-NCC cascade activation in the db/db mouse model of hyperinsulinemic metabolic syndrome. Thiazide sensitivity was increased, suggesting greater activity of NCC in db/db mice. In fact, increased phosphorylation of OSR1/SPAK and NCC was observed. In both SpakT243A/+ and Osr1T185A/+ knock-in db/db mice, which carry mutations that disrupt the signal from WNK kinases, increased phosphorylation of NCC and elevated blood pressure were completely corrected, indicating that phosphorylation of SPAK and OSR1 by WNK kinases is required for the increased activation and phosphorylation of NCC in this model. Renal phosphorylated Akt was increased in db/db mice, suggesting that increased NCC phosphorylation is regulated by the phosphatidylinositol 3-kinase/Akt signaling cascade in the kidney in response to hyperinsulinemia. A phosphatidylinositol 3-kinase inhibitor (NVP-BEZ235) corrected the increased OSR1/SPAK-NCC phosphorylation. Another more specific phosphatidylinositol 3-kinase inhibitor (GDC-0941) and an Akt inhibitor (MK-2206) also inhibited increased NCC phosphorylation. These results indicate that the phosphatidylinositol 3-kinase/Akt signaling pathway activates the WNK-OSR1/SPAK-NCC phosphorylation cascade in db/db mice. This mechanism may play a role in the pathogenesis of salt-sensitive hypertension in human hyperinsulinemic conditions, such as the metabolic syndrome.

The effect of indapamide versus hydrochlorothiazide on ventricular and arterial function in patients with hypertension and diabetes: results of a randomized trial.

PubMed

Vinereanu, Dragos; Dulgheru, Raluca; Magda, Stefania; Dragoi Galrinho, Ruxandra; Florescu, Maria; Cinteza, Mircea; Granger, Christopher; Ciobanu, Andrea O

2014-10-01

The objective of this study is to compare the effects of 2 types of diuretics, indapamide and hydrochlorothiazide, added to an angiotensin-converting enzyme inhibitor, on ventricular and arterial functions in patients with hypertension and diabetes. This is a prospective, randomized, active-controlled, PROBE design study in 56 patients (57 ± 9 years, 52% men) with mild-to-moderate hypertension and type 2 diabetes, with normal ejection fraction, randomized to either indapamide (1.5 mg Slow Release (SR)/day) or hydrochlorothiazide (25 mg/d), added to quinapril (10-40 mg/d). All patients had conventional, tissue Doppler and speckle tracking echocardiography and assessment of endothelial and arterial functions and biomarkers, at baseline and after 6 months. Baseline characteristics were similar between groups; systolic and diastolic blood pressures decreased similarly, by 15% and 9% on indapamide and by 17% and 10% on hydrochlorothiazide (P < .05). Mean longitudinal systolic velocity and longitudinal strain increased by 7% and 14% on indapamide (from 5.6 ± 1.8 to 6.0 ± 1.1 cm/s and from 16.2% ± 1.8% to 18.5% ± 1.1%, both P < .05), but did not change on hydrochlorothiazide (P < .05 for intergroup differences), whereas ejection fraction and radial systolic function did not change. Similarly, mean longitudinal early diastolic velocity increased by 31% on indapamide (P < .05), but did not change on hydrochlorothiazide (P < .05 for intergroup differences). These changes were associated with improved endothelial and arterial functions on indapamide, but not on hydrochlorothiazide. Indapamide was found to improve measures of endothelial and arterial functions and to increase longitudinal left ventricular function compared with hydrochlorothiazide in patients with hypertension and diabetes, after 6 months of treatment. This study suggests that indapamide, a thiazide-like diuretic, has important vascular effects that can improve ventriculoarterial coupling. Copyright © 2014 Mosby, Inc. All rights reserved.

Total, Dietary, and Supplemental Vitamin C Intake and Risk of Incident Kidney Stones

PubMed Central

Ferraro, Pietro Manuel; Curhan, Gary C.; Gambaro, Giovanni; Taylor, Eric N.

2015-01-01

Background Previous studies of vitamin C and kidney stones were conducted mostly in men and either reported disparate results for supplemental and dietary vitamin C or did not examine dietary vitamin C. Study Design Prospective cohort analysis. Setting & Participants 156,735 women in the Nurses’ Health Study (NHS) I and II and 40,536 men in the Health Professionals Follow-up Study (HPFS). Predictor Total, dietary and supplemental vitamin C intake, adjusted for age, BMI, thiazide use, and dietary factors. Outcomes Incident kidney stones Results During median follow-up of 11.3–11.7 years, 6,245 incident kidney stones were identified. After multivariable adjustment, total vitamin C intake (<90 [reference], 90–249, 250–499, 500–999 and ≥1,000 mg/d) was not significantly associated with the risk of kidney stones among women, but was among men (HRs of 1.00 [reference], 1.19 [95% CI, 0.99–1.46], 1.15 [95% CI, 0.93–1.42], 1.29 [95% CI, 1.04–1.60] and 1.43 [95% CI, 1.15–1.79], respectively; p for trend = 0.005). Median total vitamin C intake for the 500–999 mg/d category was about 700 mg/d. Supplemental vitamin C intake (no use [reference], <500, 500–999, and ≥1,000 mg/d) was not significantly associated with the risk of kidney stones among women, but was among men (HR, 1.19 [95% CI, 1.01–1.40] for ≥1,000 mg/d; p for trend = 0.001). Dietary vitamin C intake was not associated with stones among men or women, although few participants had dietary intakes >700 mg/d. Limitations Nutrient intakes derived from food-frequency questionnaires, lack of data on stone composition for all the cases. Conclusions Total and supplemental intake of vitamin C was significantly associated with a higher risk of incident kidney stones in men, but not among women. PMID:26463139

Clinical Overview of Nephrogenic Diabetes Insipidus Based on a Nationwide Survey in Japan

PubMed Central

Fujimoto, Masanobu; Okada, Shin-ichi; Kawashima, Yuki; Nishimura, Rei; Miyahara, Naoki; Kawaba, Yasuo; Hanaki, Keiichi; Nanba, Eiji; Kondo, Yoshiaki; Igarashi, Takashi; Kanzaki, Susumu

2014-01-01

Background Nephrogenic diabetes insipidus (NDI) is a rare disease whose complications include polyuria, renal dysfunction, growth disorder and mental retardation. The details of NDI’s clinical course have been unclear. To address this uncertainty, we performed a large investigation of the clinical course of NDI in Japan. Methods Between December 2009 and March 2011, we provided a primary questionnaire to 26,282 members of the Japan Endocrine Society, the Japanese Urological Association, the Japanese Society for Pediatric Endocrinology, the Japanese Society for Pediatric Nephrology, the Japanese Society of Nephrology, the Japanese Society of Neurology and the Japanese Society of Pediatric Urology. In addition, we provided a secondary questionnaire to 121 members who reported experience with cases of NDI. We asked about patient’s age at onset, diagnosis, complications, effect of treatment and patient’s genotype. Results We enrolled 173 patients with NDI in our study. Of these NDI patients, 143 were congenital and 30 were acquired. Of the 173, 73 patients (42%) experienced urologic complications. Among the 143 with congenital NDI, 20 patients (14%) had mental retardation. Patients with NDI mainly received thiazide diuretics, and some patients responded to treatment with desmopressin acetate (DDAVP). Gene analyses were performed in 87 patients (61%) with congenital NDI, revealing that 65 patients had an arginine vasopressin receptor type 2 (AVPR2) gene mutation and that 8 patients (9.2%) had an aquaporin 2 (AQP2) gene mutation. Patients with the AVPR2 mutation (D85N) generally showed a mild phenotype, and we found that DDAVP was generally an effective treatment for NDI among these patients. Conclusion We suggest that adequate diagnosis and treatment are the most important factors for improving prognoses. We further suggest that gene analysis should be performed for optimal treatment selection and the early detection of NDI among siblings. PMID:25324589

The Role of Intercalated Cell Nedd4-2 in BP Regulation, Ion Transport, and Transporter Expression.

PubMed

Nanami, Masayoshi; Pham, Truyen D; Kim, Young Hee; Yang, Baoli; Sutliff, Roy L; Staub, Olivier; Klein, Janet D; Lopez-Cayuqueo, Karen I; Chambrey, Regine; Park, Annie Y; Wang, Xiaonan; Pech, Vladimir; Verlander, Jill W; Wall, Susan M

2018-06-01

Background Nedd4-2 is an E3 ubiquitin-protein ligase that associates with transport proteins, causing their ubiquitylation, and then internalization and degradation. Previous research has suggested a correlation between Nedd4-2 and BP. In this study, we explored the effect of intercalated cell (IC) Nedd4-2 gene ablation on IC transporter abundance and function and on BP. Methods We generated IC Nedd4-2 knockout mice using Cre-lox technology and produced global pendrin/ Nedd4-2 null mice by breeding global Nedd4-2 null ( Nedd4-2 -/- ) mice with global pendrin null ( Slc26a4 -/- ) mice. Mice ate a diet with 1%-4% NaCl; BP was measured by tail cuff and radiotelemetry. We measured transepithelial transport of Cl - and total CO 2 and transepithelial voltage in cortical collecting ducts perfused in vitro Transporter abundance was detected with immunoblots, immunohistochemistry, and immunogold cytochemistry. Results IC Nedd4-2 gene ablation markedly increased electroneutral Cl - /HCO 3 - exchange in the cortical collecting duct, although benzamil-, thiazide-, and bafilomycin-sensitive ion flux changed very little. IC Nedd4-2 gene ablation did not increase the abundance of type B IC transporters, such as AE4 ( Slc4a9 ), H + -ATPase, barttin, or the Na + -dependent Cl - /HCO 3 - exchanger ( Slc4a8 ). However, IC Nedd4-2 gene ablation increased CIC-5 total protein abundance, apical plasma membrane pendrin abundance, and the ratio of pendrin expression on the apical membrane to the cytoplasm. IC Nedd4-2 gene ablation increased BP by approximately 10 mm Hg. Moreover, pendrin gene ablation eliminated the increase in BP observed in global Nedd4-2 knockout mice. Conclusions IC Nedd4-2 regulates Cl - /HCO 3 - exchange in ICs., Nedd4-2 gene ablation increases BP in part through its action in these cells. Copyright © 2018 by the American Society of Nephrology.

Hemodynamic and metabolic effects of estrogen plus progestin therapy in hypertensive postmenopausal women treated with an ACE-inhibitor or a diuretic.

PubMed

Posadzy-Malaczynska, Anna; Rajpold, Katarzyna; Woznicka-Leskiewicz, Lucyna; Marcinkowska, Justyna

2015-01-01

The aim of the study was to assess the hemodynamic and metabolic actions of estrogen plus progestin therapy (EPT) in hypertensive, postmenopausal women treated with perindopril (ACEI) or hydrochlorothiazide (HCTZ). A group of normotensive postmenopausal women was also studied. 100 hypertensive and 40 normotensive postmenopausal women were recruited for the study. The hypertensive females were randomly assigned to receive ACEI or HCTZ for 12 months. The patients of the ACEI group and the patients of the HCTZ group, as well as normotensives, were further subdivided into two subgroups each. One subgroup received estrogen plus progestin therapy (EPT+), the other subgroup received no hormone replacement (EPT-). Combined hormone replacement with transdermal patches releasing 17β-estradiol and norethisterone was used. Office and 24-hour ambulatory blood pressure was measured at baseline and during follow-up. Renal plasma flow (RPF) was measured using the clearance of [125I]-iodohippuran. Pulse wave velocity (PWV) was determined with an automatic device. In normotensive postmenopausal women, transdermal estrogen plus progestin therapy increases RPF and insulin sensitivity, decreases PWV, decreases total and LDL cholesterol, and decreases uric acid serum levels. Perindopril (4 mg/day) and hydrochlorothiazide (25 mg/day) were equally effective in reducing blood pressure in postmenopausal, hypertensive subjects. In these females, perindopril increased RPF and decreased PWV and plasma insulin levels. These effects of the ACEI were not altered by estrogen plus progestin therapy. Hydrochlorothiazide decreased RPF and increased plasma insulin and uric acid concentrations in hypertensive subjects whom were not receiving estrogen plus progestin therapy. The unfavorable metabolic and hemodynamic actions of the diuretic were counteracted by estrogen plus progestin therapy. Concomitant estrogen plus progestin therapy may be a method to avoid unfavorable hemodynamic and metabolic effects of thiazide diuretics in hypertensive, postmenopausal women.

Risk of Hypertension among First-Time Symptomatic Kidney Stone Formers

PubMed Central

Kittanamongkolchai, Wonngarm; Mara, Kristin C.; Mehta, Ramila A.; Vaughan, Lisa E.; Denic, Aleksandar; Knoedler, John J.; Enders, Felicity T.; Lieske, John C.

2017-01-01

Background and objectives Prior work has suggested a higher risk of hypertension in kidney stone formers but lacked disease validation and adjustment for potential confounders. Certain types of stone formers may also be at higher risk of hypertension. Design, setting, participants, & measurements In our study, incident symptomatic stone formers in Olmsted County from 2000 to 2011 were manually validated by chart review and age and sex matched to Olmsted County controls. We followed up patients through November 20, 2015. Hypertension was also validated by manual chart review, and the risk of hypertension in stone formers compared with controls was assessed both univariately and after adjusting for comorbidities. The risk of hypertension among different subtypes of stone formers was also evaluated. Results Among 3023 coded stone formers from 2000 to 2011, a total of 1515 were validated and matched to 1515 controls (mean age was 45 years old, and 56% were men). After excluding those with baseline hypertension (20% of stone formers and 18% of controls), 154 stone formers and 110 controls developed hypertension. Median follow-up time was 7.8 years in stone formers and 9.6 years in controls. Stone formers were found to have a higher risk of hypertension compared with controls (hazard ratio, 1.50; 95% confidence interval, 1.18 to 1.92), even after adjusting for age, sex, body mass index, serum creatinine, CKD, diabetes, gout, coronary artery disease, dyslipidemia, tobacco use, and alcohol abuse (hazard ratio, 1.58; 95% confidence interval, 1.12 to 2.21). Results were similar after excluding patients who were ever on a thiazide diuretic (hazard ratio, 1.65; 95% confidence interval, 1.16 to 2.38). Stone composition, radiographic stone burden, number of subsequent stone events, and stone removal surgeries were not associated with hypertension (P>0.05 for all). Conclusions The risk of hypertension was higher after the first symptomatic kidney stone event. However, kidney stone severity, type, and treatment did not associate with hypertension. PMID:28148559

Stability-Indicating HPTLC Method for Studying Stress Degradation Behavior of Sulbutiamine HCl.

PubMed

Farid, Nehal F; Abdelwahab, Nada S

2016-04-01

Sulbutiamine (SUL) is an ester of thiazides with neurotropic action. A new stability indicating HPTLC method has been developed and validated for the determination of SUL in the presence of different degradation products. The drug was subjected to different stress conditions following ICH strategy such as hydrolytic degradation (neutral, alkaline and acidic hydrolysis), oxidation, photodegradation and dry heat degradation. The drug demonstrated degradation under all decomposition conditions except neutral hydrolysis and dry heat, where the drug was completely degraded with 0.1 N NaOH, 1 N HCl and 30% H2O2 while it was partially degradaed by 0.1 N HCl, 3% H2O2 and UV light. Structure elucidation of the resulting degradation products was performed using ESI-Q-MS-MS. A well-defined peak for SUL was obtained at Rf = 0.46 and was completely separated from all obtained degradation products. Chromatographic separation was carried out on HPTLC aluminum plates precoated with silica gel 60 F254 using acetone-methylene chloride-ammonia buffer (pH 8.5 ± 0.2) (7:3:0.5, v/v) as a developing system. Densitometric scanning of the separated peaks was performed at 254 nm. System suitability testing parameters were calculated to ascertain the quality performance of the developed method. The method was validated with respect to USP guidelines regarding accuracy, precision, specificity, robustness and ruggedness. Good correlation coefficients were achieved in the range of 0.4-5.0 µg/band, and the limit of detection and limit of quantitation were found to be 0.11 and 0.33 µg/band, respectively. The utility of the suggested method was verified by application to Arcalion forte® tablets where no interference from additives was found. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Total, Dietary, and Supplemental Vitamin C Intake and Risk of Incident Kidney Stones.

PubMed

Ferraro, Pietro Manuel; Curhan, Gary C; Gambaro, Giovanni; Taylor, Eric N

2016-03-01

Previous studies of vitamin C and kidney stones were conducted mostly in men and either reported disparate results for supplemental and dietary vitamin C or did not examine dietary vitamin C. Prospective cohort analysis. 156,735 women in the Nurses' Health Study (NHS) I and II and 40,536 men in the Health Professionals Follow-up Study (HPFS). Total, dietary, and supplemental vitamin C intake, adjusted for age, body mass index, thiazide use, and dietary factors. Incident kidney stones. During a median follow-up of 11.3 to 11.7 years, 6,245 incident kidney stones were identified. After multivariable adjustment, total vitamin C intake (<90 [reference], 90-249, 250-499, 500-999, and ≥1,000mg/d) was not significantly associated with risk for kidney stones among women, but was among men (HRs of 1.00 [reference], 1.19 [95% CI, 0.99-1.46], 1.15 [95% CI, 0.93-1.42], 1.29 [95% CI, 1.04-1.60], and 1.43 [95% CI, 1.15-1.79], respectively; P for trend = 0.005). Median total vitamin C intake for the 500- to 999-mg/d category was ∼700mg/d. Supplemental vitamin C intake (no use [reference], <500, 500-999, and ≥1,000mg/d) was not significantly associated with risk for kidney stones among women, but was among men (HR, 1.19 [95% CI, 1.01-1.40] for ≥1,000mg/d; P for trend = 0.001). Dietary vitamin C intake was not associated with stones among men or women, although few participants had dietary intakes > 700mg/d. Nutrient intakes derived from food-frequency questionnaires, lack of data on stone composition for all cases. Total and supplemental vitamin C intake was significantly associated with higher risk for incident kidney stones in men, but not in women. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Hydrochlorothiazide and alternative diuretics versus renin-angiotensin system inhibitors for the regression of left ventricular hypertrophy: a head-to-head meta-analysis.

PubMed

Roush, George C; Abdelfattah, Ramy; Song, Steven; Kostis, John B; Ernst, Michael E; Sica, Domenic A

2018-06-01

Found in 36-41% of hypertension, elevated left ventricular mass (LVM) independently predicts cardiovascular events and total mortality. Conversely, drug-induced regression of LVM predicts improved outcomes. Previous studies have favored renin-angiotensin system inhibitors (RASIs) over other antihypertensives for reducing LVM but ignored differences among thiazide-type diuretics. From evidence regarding potency, cardiovascular events, and electrolytes, we hypothesized a priori that 'CHIP' diuretics [CHlorthalidone, Indapamide and Potassium-sparing Diuretic/hydrochlorothiazide (PSD/HCTZ)] would rival RASIs for reducing LVM. Systematic review yielded 12 relevant double-blind randomized trials. CHIPs were more closely associated with reduced LVM than HCTZ (P = 0.004), indicating that RASIs must be compared with each diuretic separately. Publication bias favoring RASIs was corrected by cumulative analysis. For reducing LVM, HCTZ tended to be less effective than RASIs. However, the following surpassed RASIs: chlorthalidone Hedge's G: -0.37 (95% CI -0.72 to -0.02), P = 0.036; indapamide -0.20 (-0.39 to -0.01), P = 0.035; all CHIPs combined (with 61% of patients in one trial) -0.25 (-0.41to -0.09), P = 0.002. Statistical significance (P < 0.05) did not depend on any one trial. CHIPs reduction in LVM was 37% greater than that from RASIs. CHIPs superiority tended to increase with trial duration, from a negligible effect at 0.5 year to a maximal effect at 0.9-1.0 years: -0.26 (-0.43 to -0.09), P = 0.003. Fifty-eight percent of patients had information on echocardiographic components of LVM: relative to RASIs, CHIPs significantly reduced end-diastolic LV internal dimension (EDLVID): -0.18 (-0.36 to -0.00), P = 0.046. Strength of evidence favoring CHIPs over RASIs was at least moderate. In these novel results in patients with hypertension, CHIPs surpassed RASIs for reducing LVM and EDLVID.

Synergistic effect of statins and postmenopausal hormone therapy in the prevention of skeletal fractures in elderly women.

PubMed

Bakhireva, Ludmila N; Shainline, Michael R; Carter, Shelley; Robinson, Scott; Beaton, Sarah J; Nawarskas, James J; Gunter, Margaret J

2010-09-01

To examine the role of concurrent 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin) use and postmenopausal hormone therapy on osteoporosis-related fractures. Case-control study. Data Source. Large integrated health plan in New Mexico. Patients. Case patients were 1001 women with incident fractures of the hip, wrist, forearm, or spine that occurred between January 1, 2000, and December 31, 2005, and controls were 2607 women without fractures during the same time frame; both groups were selected from the same population of women aged 50 years or older who utilized health plan services during the study time frame. Postmenopausal hormone therapy use was classified as "current" (12 mo before index date) or "never or past." The risk of fractures was ascertained among continuous (> or = 80% medication possession ratio during 12 mo before the index date) and current (3 mo before index date) statin users relative to patients without hyperlipidemia who did not use lipid-lowering drugs. The interaction between statins and hormone therapy was examined in multivariable logistic regression. The association between statin use and fractures was examined separately among current and never or past hormone therapy users after controlling for other risk factors. Nineteen percent of the study participants were current hormone therapy users; 9.5% were current and 4.8% were continuous statin users. No association between continuous statin use and fractures was observed among never or past hormone therapy users (odds ratio [OR] 0.80, 95% confidence interval [CI] 0.53-1.22). In contrast, a strong protective effect (OR 0.19, 95% CI 0.04-0.87) was observed among women who concurrently used statins and hormone therapy for 1 year, independent of age; corticosteroid, bisphosphonate, thiazide diuretic, calcitonin, methotrexate, or antiepileptic drug use; chronic kidney disease; and Charlson comorbidity index. Concurrent statin use and hormone therapy may have a synergistic protective effect on skeletal fractures beyond the additive effect of each individual therapy.

Associations between oral and ocular dryness, labial and whole salivary flow rates, systemic diseases and medications in a sample of older people.

PubMed

Smidt, D; Torpet, L A; Nauntofte, B; Heegaard, K M; Pedersen, A M L

2011-06-01

To investigate the associations between age, gender, systemic diseases, medications, labial and whole salivary flow rates and oral and ocular dryness in older people. Symptoms of oral and ocular dryness, systemic diseases, medications (coded according to the Anatomical therapeutic chemical (ATC) classification system), tobacco and alcohol consumption were registered, and unstimulated labial (LS) and unstimulated (UWS) and chewing-stimulated (SWS) whole salivary flow rates were measured in 668 randomly selected community-dwelling elderly aged 65-95. Presence of oral (12%) and ocular (11%) dryness was positively correlated. Oral dryness was associated with low UWS, SWS and LS, and ocular dryness with low UWS and SWS. Oral and ocular dryness was related to female gender, but not to age. Only four persons in the healthy and nonmedicated subgroups reported oral and ocular dryness. The numbers of diseases and medications were higher in the older age groups and associated with oral and ocular dryness, low UWS, SWS and LS. On average, women were slightly older, reported more oral and ocular dryness and had lower UWS, SWS, LS and higher numbers of diseases and medications. High prevalence and odds ratios for oral dryness were associated with metabolic, respiratory and neurological diseases and intake of thyroid hormones, respiratory agents (primarily glucocorticoids), psycholeptics and/or psychoanaleptics, antineoplastics, proton pump inhibitors, antidiabetics, loop diuretics, antispasmodics, quinine and bisphosphonates. Ocular dryness was especially associated with neurological diseases and intake of psycholeptics and/or psychoanaleptics. Intake of magnesium hydroxide, antithrombotics, cardiac agents, thiazides, beta-blockers, calcium channel blockers, ACE inhibitors/angiotensin II antagonists, statins, glucosamine, paracetamol/opioids, ophthalmologicals and certain combination therapies was related to oral and ocular dryness. In older people, oral and ocular dryness are associated with low salivary flow rates, specific as well as high number of diseases and medications, but neither with age and gender per se nor with tobacco and alcohol consumption. New detailed information concerning associations between medications and oral and ocular dryness has been obtained using the ATC classification system. © 2010 John Wiley & Sons A/S.

Associations between labial and whole salivary flow rates, systemic diseases and medications in a sample of older people.

PubMed

Smidt, Dorte; Torpet, Lis Andersen; Nauntofte, Birgitte; Heegaard, Karen Margrethe; Pedersen, Anne Marie Lynge

2010-10-01

To investigate the associations between age, gender, systemic diseases, medications and labial and whole salivary flow rates in older people. Unstimulated labial (LS) and unstimulated (UWS) and chewing-stimulated (SWS) whole salivary flow rates were measured in 389 randomly selected community-dwelling Danish women and 279 men aged 65-97 years. Systemic diseases, medications (coded according to the Anatomical Therapeutic Chemical (ATC) Classification System), tobacco and alcohol consumption were registered. The number of diseases and medications was higher and UWS lower in the older age groups. On average, women were slightly older, had more diseases, higher medication intake and lower UWS, SWS and LS than men. High number of diseases and medications was associated with low UWS, SWS and LS. In the healthy (14%) and nonmedicated (19%) participants, flow rates were not associated with age and gender, apart from SWS being lower in nonmedicated women. Low UWS were associated with psychiatric and respiratory disorders, type 2 diabetes and intake of psycholeptics, psychoanaleptics (especially SRRIs), respiratory agents, oral antidiabetics (particularly sulfonylureas), magnesium-hydroxide, cardiac agents, quinine, thiazides, calcium channel blockers, statins, urinary antispasmodics, glucosamine, NSAIDs, opioids and ophthalmologicals. SWS were lower in participants with ophthalmological disorders using ophthalmologicals (especially antiglaucoma agents and miotics), but also in those taking antidepressants, cardiac agents (mostly digitalis glycosides) and calcium channel blockers. Cardiovascular diseases and intake of anti-thrombotics (mainly low dose aspirins), calcium channel blockers and oral antidiabetics were associated with low LS. In older people, low salivary flow rates are associated with specific and high number of diseases and medications, but neither with age and gender per se nor with tobacco and alcohol consumption. Low UWS are associated with more diseases and medications than SWS and LS, which were primarily associated with cardiovascular diseases and medications including preventive agents such as low-dose aspirins and statins. New insights into medications and their association with salivary gland function were achieved using the ATC classification system. © 2010 John Wiley & Sons A/S.

What differentiates primary care physicians who predominantly prescribe diuretics for treating mild to moderate hypertension from those who do not? A comparative qualitative study.

PubMed

Rochefort, Christian M; Morlec, Julia; Tamblyn, Robyn M

2012-02-29

Thiazide diuretics are cost-effective for the treatment of mild to moderate hypertension, but physicians often opt for more expensive treatment options such as angiotensin II receptor blockers or angiotensin converting enzyme inhibitors. With escalating health care costs, there is a need to elucidate the factors influencing physicians' treatment choices for this highly prevalent chronic condition. The purpose of this study was to describe the characteristics of physicians' decision-making process regarding hypertension treatment choices. A comparative qualitative study was conducted in 2009 in the Canadian province of Quebec. Overall, 29 primary care physicians--who are also participating in an electronic health record research program--participated in a semi-structured interview about their prescribing decisions. Physicians were categorized into two groups based on their patterns of prescribing antihypertensive drugs: physicians who predominantly prescribe diuretics, and physicians who predominantly prescribe drug classes other than diuretics. Cases of hypertension that were newly started on antihypertensive therapy were purposely selected from each physician's electronic health record database. Chart stimulated recall interview, a technique utilizing patient charts to probe recall and provide context to physician decision-making during clinical encounters, was used to elucidate reasons for treatment choices. Interview transcripts were synthesized using content analysis techniques, and factors influencing physicians' decision making were inductively generated from the data. We identified three themes that differentiated physicians who predominantly prescribe diuretics from those who predominantly prescribe other drug classes for the initial treatment of mild to moderate hypertension: a) perceptions about the efficacy of diuretics, b) preferred approach to hypertension management and, c) perceptions about hypertension guidelines. Specifically, physicians had differences in beliefs about the efficacy, safety and tolerability of diuretics, the most effective approach for managing mild to moderate hypertension, and in aggressiveness to achieve treatment targets. Marketing strategies employed by the pharmaceutical industry and practice experience appear to contribute to these differences in management approach. Physicians preferring more expensive treatment options appear to have several misperceptions about the efficacy, safety and tolerability of diuretics. Efforts to increase physicians' prescribing of diuretics may need to be directed at overcoming these misperceptions.

Patients with gout can be cured in primary care.

PubMed

Rees, Frances; Doherty, Michael

2014-12-01

Gout affects 2.5% of the total UK population and is four times more common in men than women. The peak prevalence and incidence in the UK is in those aged 80-84 years. Gout is associated with comorbidities such as nephrolithiasis, chronic renal impairment, metabolic syndrome, depression and heart disease. It is also associated with increased mortality. Untreated gout can result in disabling irreversible peripheral joint damage and chronic usage-related pain. However, gout is curable. The pathogenic agents that cause gout i.e.urate crystals can be eliminated through a combination of effective patient education and evidence-based, targeted urate-lowering therapy. Gout is caused by the precipitation of monosodium urate crystals in and around a joint. The crystals preferentially form in peripheral, cooler joints and especially in those with osteoarthritis. It is thought that some of these preformed crystals within articular cartilage spill over into the joint space and trigger an acute attack of inflammation. Uric acid is predominantly renally excreted and the common heritable component of gout results from relative inefficiency of urate excretion. Chronic kidney disease, metabolic syndrome and drugs that reduce renal function (e.g. thiazide diuretics, beta-blockers and ACE inhibitors) will all lead to reduced elimination. Patients with chronic gout can present with monoarthritis but more commonly present with asymmetrical polyarthritis or tophi. Joints affected by osteoarthritis are preferentially targeted, the most common sites of involvement are feet, knees, hands and elbows. Diagnosis can be confirmed in primary care by taking a good history and clinical examination. An acute peripheral monoarthritis which reaches its peak within 24 hours and causes 'the worst pain ever experienced' is characteristic of an acute attack. A patient may have co-existing risk factors for gout such as osteoarthritis, obesity, hypertension, renal impairment, diuretic and antihypertensive drug use or increased beer or spirit consumption. A raised serum uric acid can confirm the diagnosis, however, this can be normal in the acute phase. Radiographs are rarely helpful but joint ultrasound may demonstrate deposits in cartilage, the synovium and peri-articular sites.

[Effects of long-term antihypertensive therapy with losartan on blood pressure and cognitive function in patients with essential hypertension and other cerebrovascular risk factors (AWARE observational study)].

PubMed

Schrader, Jürgen; Lüders, Stephan; Diener, Hans-Christoph; Haller, Hermann; Schmieder, Roland E; Wahle, Klaus; Smolka, Wenefrieda; Jung, Claudia; Bestehorn, Kurt

2008-07-15

As arterial hypertension is the most important risk factor for ischemic stroke, the relevant guidelines recommend rigorous treatment to normalize blood pressure. Hypertension can also be associated with cognitive decline and dementia. Therefore, the effect of a long-term therapy with the AT(1) antagonist losartan (+/- hydro chloro thiazide [HCTZ]) on cognitive function in patients with essential hypertension and additional cerebrovascular risk factors was investigated. Prospective, open observational study in 6,206 adult patients with known essential hypertension and cerebrovascular risk factors (most with a 10-year stroke risk of >or= 20% based on the Framingham Score). Demographic data, blood pressure, selected laboratory parameters, and cognitive function (c.I. test) were determined at baseline and after 3, 6, and 12 months. The patients' mean age was 65.8+/-10.7 years and 46.1% of the patients were male. In addition to treatment with losartan +/- HCTZ, 54.1% of the patients received one or more additional antihypertensive agents. After 1 year of treatment, systolic/diastolic blood pressure fell from its baseline level of 158.1/90.3 mmHg to 137.3/80.6 mmHg (-20.8/-9.7 mmHg). The proportion of patients with no/mild/severe cognitive impairment was 30.0%/30.3%/39.7% at baseline and 34.8%/28.1%/37.1% at the end of the study. In patients with cognitive impairment, fibrinogen and hsCRP (high-sensitive C-reactive protein) levels were significantly elevated. Adverse events (AEs) were reported in 231 patients (3.7%), while serious/nonserious AEs possibly related to the study medication were reported in only six (0.1%) and 38 patients (0.6%), respectively. A high proportion of patients with hypertension shows cognitive impairment; therefore, use of appropriate tests to detect this should be considered. The losartan-based antihypertensive treatment increased the proportion of patients with normal cognitive function, reduced blood pressure, and was well tolerated in the primary-care setting.

Blood Pressure Control and Cardiovascular Outcomes in Normal, Overweight, and Obese Hypertensives Treated with Three Different Anti-Hypertensives in ALLHAT

PubMed Central

Reisin, Efrain; Graves, John; Yamal, Jose-Miguel; Barzilay, Joshua I; Pressel, Sara; Einhorn, Paula T.; Dart, Richard A.; Retta, Tamrat M.; Saklayen, Mohammad G.; Davis, Barry R

2017-01-01

Objective Epidemiologically there is a strong relationship between body mass index (BMI) and blood pressure (BP) levels. We prospectively examined randomization to first-step chlorthalidone, a thiazide-type diuretic; amlodipine, a calcium-channel blocker; and lisinopril, an angiotensin-converting-enzyme inhibitor, on BP control and cardiovascular outcomes in a hypertensive cohort stratified by baseline BMI (normal weight [BMI<25], overweight [BMI=25–29·9], and obese [BMI≥30]). Methods 33,357 hypertensive participants, age ≥55 years were followed for an average of 4·9 years in a randomized, double-blind, practice-based Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), for primary outcome of fatal coronary heart disease (CHD) or nonfatal myocardial infarction and secondary outcomes of stroke, heart failure, combined cardiovascular disease, mortality, and renal failure. Results Of participants, 37·9% were overweight and 42·1% were obese at randomization. For each medication, BP control (<140/90 mmHg) was equivalent in each BMI stratum. At year five, 66·1%, 66·5%, and 65·1% of normal weight, overweight, and obese participants, respectively, were controlled. Those randomized to chlorthalidone had highest BP control (67·2%, 68·3%, and 68·4%, respectively) and lisinopril the lowest (60·4%, 63·2%, and 59·6%, respectively) in each BMI stratum. A significant interaction (p=0·004) suggests a lower CHD risk in the obese for lisinopril vs. chlorthalidone (hazard ratio [HR]=0·85, 95% confidence interval [CI]=[0·74–0·98]) and a significant interaction (p=0·011) suggests a higher risk of end-stage renal disease for amlodipine vs. chlorthalidone in obese participants (HR [95% CI]=1·49[1·06–2·08]). However, these results were not consistent among other outcomes. Conclusions BMI status does not modify the effects of antihypertensive medications on BP control or cardiovascular disease outcomes. PMID:24842697

Medication Nonadherence and Effectiveness of Preventive Pharmacological Therapy for Kidney Stones.

PubMed

Dauw, Casey A; Yi, Yooni; Bierlein, Maggie J; Yan, Phyllis; Alruwaily, Abdulrahman F; Ghani, Khurshid R; Wolf, J Stuart; Hollenbeck, Brent K; Hollingsworth, John M

2016-03-01

Among patients with kidney stones rates of adherence to thiazide diuretics, alkali citrate therapy and allopurinol, collectively referred to as preventive pharmacological therapy, are low. This lack of adherence may reduce the effectiveness of secondary prevention efforts, leading to poorer clinical health outcomes in patients with kidney stones. To examine the impact that medication nonadherence has on the secondary prevention of kidney stones, we compared clinical health outcomes between patients who adhered to their regimen and those who did not. Using medical and pharmacy claims data we identified adult patients with a physician coded diagnosis for kidney stones. Among the subset with a prescription fill for a preventive pharmacological therapy agent, we then measured adherence to therapy within the first 6 months of initiating treatment using the proportion of days covered formula. We defined adherence as a proportion of days covered value of 80% or greater. Finally, we fitted multivariable logistic regression models to examine the association between medication adherence and the occurrence of a stone related clinical health outcome (an emergency department visit, hospitalization or surgery for stone disease). Of the 8,950 patients who met the study eligibility criteria slightly more than half (51.1%) were adherent to preventive pharmacological therapy. The frequency of emergency department visits, hospitalization and surgery for stone disease was significantly lower among adherent patients. After controlling for sociodemographic factors and the level of comorbid illness, patients who were adherent to therapy had 27% lower odds of an emergency department visit (OR 0.73, 95% CI 0.64-0.84), 41% lower odds of hospital admission (OR 0.59, 95% CI 0.49-0.71) and 23% lower odds of surgery for stone disease (OR 0.77, 95% CI 0.69-0.85) than nonadherent patients. Our data highlight the consequences of nonadherence to preventive pharmacological therapy among patients with kidney stones. To improve adherence further research is needed to understand patient and provider level factors that contribute to lower rates of adherence. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

The Clinical Physiology of Water Metabolism

PubMed Central

Weitzman, Richard E.; Kleeman, Charles R.

1979-01-01

The renal reabsorption of water independent of solute is the result of the coordinated function of the collecting duct and the ascending limb of the loop of Henle. The unique juxtaposition of the ascending and descending portions of the loop of Henle and of the vasa recta permits the function of a counter-current multiplier system in which water is removed from the tubular lumen and reabsorbed into the circulation. The driving force for reabsorption is the osmotic gradient in the renal medulla which is dependent, in part, on chloride (followed by sodium) pumping from the thick ascending loop of Henle. Urea trapping is also thought to play an important role in the generation of a hypertonic medullary interstitium. Arginine vasopressin (AVP) acts by binding to receptors on the cell membrane and activating adenylate cyclase. This, inturn, results in the intracellular accumulation of cyclic adenosine monophosphate (AMP) which in some fashion abruptly increases the water permeability of the luminal membrane of cells in the collecting duct. As a consequence, water flows along an osmotic gradient out of the tubular lumen into the medullary interstitium. Diabetes insipidus is the clinical condition associated with either a deficiency of or a resistance to AVP. Central diabetes insipidus is due to diminished release of AVP following damage to either the neurosecretory nuclei or the pituitary stalk. Possible causes include idiopathic, familial, trauma, tumor, infection or vascular lesions. Patients present with polyuria, usually beginning over a period of a few days. The diagnosis is made by showing that urinary concentration is impaired after water restriction but that there is a good response to exogenous vasopressin therapy. Nephrogenic diabetes insipidus can be identified by a patient's lack of response to AVP. Nephrogenic diabetes insipidus is caused by a familial defect, although milder forms can be acquired as a result of various forms of renal disease. Central diabetes insipidus is eminently responsive to replacement therapy, particularly with dDAVP, a long lasting analogue of AVP. Nephrogenic diabetes insipidus is best treated with a combination of thiazide diuretics as well as a diet low in sodium and protein. ImagesFigure 27.Figure 31. PMID:545867

Should Antihypertensive Treatment Recommendations Differ in Patients With and Without Coronary Heart Disease? (From the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial [ALLHAT])

PubMed Central

Alderman, Michael H.; Davis, Barry R.; Piller, Linda B.; Ford, Charles E.; Baraniuk, M. Sarah; Pressel, Sara L.; Assadi, Mahshid A.; Einhorn, Paula T.; Haywood, L. Julian; Ilamathi, Ekambaram; Oparil, Suzanne; Retta, Tamrat M.

2015-01-01

Thiazide-type diuretics have been recommended for initial treatment of hypertension in most patients, but should this recommendation differ for patients with and without coronary heart disease (CHD)? The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) was a randomized, double-blind hypertension treatment trial in 42,418 participants with high risk of combined cardiovascular disease (CVD) (25% with pre-existing CHD). This post-hoc analysis compares long-term major clinical outcomes in those assigned amlodipine (n=9048) or lisinopril (n=9054) with those assigned chlorthalidone (n=15,255), stratified by CHD status. After 4–8 years, randomized treatment was discontinued. Total follow-up (active treatment + passive surveillance using national databases for deaths and hospitalizations) was 8–13 years. For most CVD outcomes, ESRD, and total mortality, there were no differences across randomized treatment arms regardless of baseline CHD status. In-trial rates of CVD were significantly higher for lisinopril compared with chlorthalidone, and rates of heart failure were significantly higher for amlodipine compared with chlorthalidone in those with and without CHD (overall HRs: 1.10, p<0.001 and 1.38, p<0.001, respectively). During extended follow-up, significant outcomes according to CHD status interactions (p=0.012) were noted in amlodipine versus chlorthalidone comparison for CVD and CHD mortality, HR=0.88, p=0.04 and 0.84, p=0.04, respectively, in those with CHD at baseline and 1.06, p=0.15 and 1.08, p=0.17 in those without. The results of the overall increased stroke mortality in lisinopril compared to chlorthalidone (HR=1.2; p=0.03) and hospitalized heart failure in amlodipine compared to chlorthalidone (HR=1.12; p=0.01) during extended follow-up did not differ by baseline CHD status. In conclusion, these results provide no reason to alter our previous recommendation to include a properly dosed diuretic (such as chlorthalidone 12.5–25 mg/day) in the initial antihypertensive regimen for most hypertensive patients. PMID:26589819

Should Antihypertensive Treatment Recommendations Differ in Patients With and Without Coronary Heart Disease? (from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial [ALLHAT]).

PubMed

Alderman, Michael H; Davis, Barry R; Piller, Linda B; Ford, Charles E; Baraniuk, M Sarah; Pressel, Sara L; Assadi, Mahshid A; Einhorn, Paula T; Haywood, L Julian; Ilamathi, Ekambaram; Oparil, Suzanne; Retta, Tamrat M

2016-01-01

Thiazide-type diuretics have been recommended for initial treatment of hypertension in most patients, but should this recommendation differ for patients with and without coronary heart disease (CHD)? The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) was a randomized, double-blind hypertension treatment trial in 42,418 participants with high risk of combined cardiovascular disease (CVD) (25% with preexisting CHD). This post hoc analysis compares long-term major clinical outcomes in those assigned amlodipine (n = 9048) or lisinopril (n = 9,054) with those assigned chlorthalidone (n = 15,255), stratified by CHD status. After 4 to 8 years, randomized treatment was discontinued. Total follow-up (active treatment + passive surveillance using national databases for deaths and hospitalizations) was 8 to 13 years. For most CVD outcomes, end-stage renal disease, and total mortality, there were no differences across randomized treatment arms regardless of baseline CHD status. In-trial rates of CVD were significantly higher for lisinopril compared with chlorthalidone, and rates of heart failure were significantly higher for amlodipine compared with chlorthalidone in those with and without CHD (overall hazard ratios [HRs] 1.10, p <0.001, and 1.38, p <0.001, respectively). During extended follow-up, significant outcomes according to CHD status interactions (p = 0.012) were noted in amlodipine versus chlorthalidone comparison for CVD and CHD mortality (HR 0.88, p = 0.04, and 0.84, p = 0.04, respectively) in those with CHD at baseline (HR 1.06, p = 0.15, and 1.08, p = 0.17) and in those without. The results of the overall increased stroke mortality in lisinopril compared with chlorthalidone (HR 1.2; p = 0.03) and hospitalized heart failure in amlodipine compared with chlorthalidone (HR 1.12; p = 0.01) during extended follow-up did not differ by baseline CHD status. In conclusion, these results provide no reason to alter our previous recommendation to include a properly dosed diuretic (such as chlorthalidone 12.5 to 25 mg/day) in the initial antihypertensive regimen for most hypertensive patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Patterns of prescription antihypertensive drug utilization and adherence to treatment guidelines in the city of Novi Sad.

PubMed

Tomas, Ana; Tomić, Zdenko; Milijasević, Boris; Ban, Milica; Horvat, Olga; Vukmirović, Sasa; Sabo, Ana

2016-06-01

Hypertension is one of the leading causes of cardiovascular morbidity and mortality and more than a half of all health insurance expenditures for reimbursed medicines are allocated to antihypertensive drugs in Serbia. The aim of this study was to identify the antihypertensive drug utilization patterns among hypertensive outpatients in the city of Novi Sad, Serbia, determine the adherence to clinical guidelines and address the economic aspects of current prescribing practices. This retrospective observational study was conducted in Novi Sad over a period of six months. The data on the number of packages, size their, and retail price of antihypertensives issued on prescription in outpatients with the diagnosis of essential arterial hypertension was collected from all state-owned pharmacies in Novi Sad. Drug consumption was analyzed using the Anatomical Therapeutic Chemical (ATC)/ defined daily dose (DDD) methodology. Total consumption of antihypertensives issued on prescription over a 6-month period in the city of Novi sad, Serbia was 283.48 DDD per 1,000 inhabitans per day (DID). Angiotensin converting enzyme inhibitors (ACEi) were most commonly prescribed drugs, and were used 3 times more often than calcium channel blockers and 5 times more than beta-blockers. The consumption of diuretics and angiotensin receptor antagonists was low within all the groups of outpatients. Both national and international guidelines state superiority and effectiveness of diuretics in treatment of hypertension in the elderly, but their consumption was unreasonable low despite the fact that over 70% of all antihypertensive drugs in the city of Novi Sad were dispensed in people aged > 60. The use of more expensive ACEi was observed despite the guidelines deeming all the drugs of this class equally effective in treatment of hypertension. Large differences in utilization of different groups of antihypertensive agents were noted in this study. Underutilization of valuable, efficacious, and cost-effective thiazide diuretics and overuse of expensive ACE inhibitors is unjustifiable. There is a potential for large savings with switching to low-price ACEi, modeling the practice of Scandinavian countries.

What differentiates primary care physicians who predominantly prescribe diuretics for treating mild to moderate hypertension from those who do not? A comparative qualitative study

PubMed Central

2012-01-01

Background Thiazide diuretics are cost-effective for the treatment of mild to moderate hypertension, but physicians often opt for more expensive treatment options such as angiotensin II receptor blockers or angiotensin converting enzyme inhibitors. With escalating health care costs, there is a need to elucidate the factors influencing physicians' treatment choices for this highly prevalent chronic condition. The purpose of this study was to describe the characteristics of physicians' decision-making process regarding hypertension treatment choices. Methods A comparative qualitative study was conducted in 2009 in the Canadian province of Quebec. Overall, 29 primary care physicians--who are also participating in an electronic health record research program--participated in a semi-structured interview about their prescribing decisions. Physicians were categorized into two groups based on their patterns of prescribing antihypertensive drugs: physicians who predominantly prescribe diuretics, and physicians who predominantly prescribe drug classes other than diuretics. Cases of hypertension that were newly started on antihypertensive therapy were purposely selected from each physician's electronic health record database. Chart stimulated recall interview, a technique utilizing patient charts to probe recall and provide context to physician decision-making during clinical encounters, was used to elucidate reasons for treatment choices. Interview transcripts were synthesized using content analysis techniques, and factors influencing physicians' decision making were inductively generated from the data. Results We identified three themes that differentiated physicians who predominantly prescribe diuretics from those who predominantly prescribe other drug classes for the initial treatment of mild to moderate hypertension: a) perceptions about the efficacy of diuretics, b) preferred approach to hypertension management and, c) perceptions about hypertension guidelines. Specifically, physicians had differences in beliefs about the efficacy, safety and tolerability of diuretics, the most effective approach for managing mild to moderate hypertension, and in aggressiveness to achieve treatment targets. Marketing strategies employed by the pharmaceutical industry and practice experience appear to contribute to these differences in management approach. Conclusions Physicians preferring more expensive treatment options appear to have several misperceptions about the efficacy, safety and tolerability of diuretics. Efforts to increase physicians' prescribing of diuretics may need to be directed at overcoming these misperceptions. PMID:22375684

Low Bone Density and Bisphosphonate Use and the Risk of Kidney Stones.

PubMed

Prochaska, Megan; Taylor, Eric; Vaidya, Anand; Curhan, Gary

2017-08-07

Previous studies have demonstrated lower bone density in patients with kidney stones, but no longitudinal studies have evaluated kidney stone risk in individuals with low bone density. Small studies with short follow-up reported reduced 24-hour urine calcium excretion with bisphosphonate use. We examined history of low bone density and bisphosphonate use and the risk of incident kidney stone as well as the association with 24-hour calcium excretion. We conducted a prospective analysis of 96,092 women in the Nurses' Health Study II. We used Cox proportional hazards models to adjust for age, body mass index, thiazide use, fluid intake, supplemental calcium use, and dietary factors. We also conducted a cross-sectional analysis of 2294 participants using multivariable linear regression to compare 24-hour urinary calcium excretion between participants with and without a history of low bone density, and among 458 participants with low bone density, with and without bisphosphonate use. We identified 2564 incident stones during 1,179,860 person-years of follow-up. The multivariable adjusted relative risk for an incident kidney stone for participants with history of low bone density compared with participants without was 1.39 (95% confidence interval [95% CI], 1.20 to 1.62). Among participants with low bone density, the multivariable adjusted relative risk for an incident kidney stone for bisphosphonate users was 0.68 (95% CI, 0.48 to 0.98). In the cross-sectional analysis of 24-hour urine calcium excretion, the multivariable adjusted mean difference in 24-hour calcium was 10 mg/d (95% CI, 1 to 19) higher for participants with history of low bone density. However, among participants with history of low bone density, there was no association between bisphosphonate use and 24-hour calcium with multivariable adjusted mean difference in 24-hour calcium of -2 mg/d (95% CI, -25 to 20). Low bone density is an independent risk factor for incident kidney stone and is associated with higher 24-hour urine calcium excretion. Among participants with low bone density, bisphosphonate use was associated with lower risk of incident kidney stone but was not independently associated with 24-hour urine calcium excretion. Copyright © 2017 by the American Society of Nephrology.

Pathophysiology of Post Transplant Hypertension in Kidney Transplant: Focus on Calcineurin Inhibitors Induced Oxidative Stress and Renal Sodium Retention and Implications with RhoA/Rho Kinase Pathway.

PubMed

Calò, Lorenzo A; Ravarotto, Verdiana; Simioni, Francesca; Naso, Elena; Marchini, Francesco; Bonfante, Luciana; Furian, Lucrezia; Rigotti, Paolo

2017-01-01

Post-transplant hypertension is a common occurrence during treatment with calcineurin inhibitors (CNIs) in kidney transplant population. The pathogenesis of vasoconstriction induced by CNIs involves vascular tone alterations and kidney sodium transport regulation. Among the factors involved a key role is played by the activation of intrarenal renin-angiotensin system with enhanced release of Angiotensin II (Ang II) and increase of oxidative stress. A common pathway between oxidative stress and hypertension induced by CNIs may be identified in the involvement of the activation of RhoA/Rho kinase pathway, key for the induction of hypertension and cardiovascular-renal remodeling, of the oxidative stress mediated increased nitric oxide (NO) metabolism and increased renal sodium retention via increased activity of thiazide-sensitive sodium chloride cotransporter (NCC) in the distal tubule. We examined literature data including those coming from our group regarding the role of oxidative stress and sodium retention in CNIs induced hypertension and their involvement in cardiovascular-renal remodeling. Based on the available data, we have provided support to the activation of RhoA/Rho kinase pathway as an important effector in the pathophysiology of CNIs induced post-transplant hypertension via activation of oxidative stress and sodium retention. Clarification of how the biochemical and molecular mechanisms that regulate the processes involved in CNIs induced post transplant hypertension work and interact, would provide further insights not only into the comprehension of the pathophysiology of CNIs induced post transplant hypertension but could also have a positive impact on the clinical ground through the identification of significant targets. Their specific pharmacologic targeting might have multiple beneficial effects on the whole cardiovascular-renal function. The demonstration that in kidney transplanted patients with CNIs induced post-transplanted hypertension, the treatment of hypertension with different antihypertensive drugs inducing a comparable blood pressure reduction but different effects for example on oxidative stress and oxidative stress related proteins and/or Rho kinase and sodium retention, could be helpful for the choice of the antihypertensive treatment in these patients which takes advantage from effects of these drugs beyond blood pressure reduction. © 2017 The Author(s). Published by S. Karger AG, Basel.

PTH modulation of NCC activity regulates TRPV5 Ca2+ reabsorption.

PubMed

Hoover, Robert S; Tomilin, Viktor; Hanson, Lauren; Pochynyuk, Oleh; Ko, Benjamin

2016-01-15

Since parathyroid hormone (PTH) is known to increase transient receptor potential vanilloid (TRPV)5 activity and decrease Na(+)-Cl(-) cotransporter (NCC) activity, we hypothesized that decreased NCC-mediated Na(+) reabsorption contributes to the enhanced TRPV5 Ca(2+) reabsorption seen with PTH. To test this, we used mDCT15 cells expressing functional TRPV5 and ruthenium red-sensitive (45)Ca(2+) uptake. PTH increased (45)Ca(2+) uptake to 8.8 ± 0.7 nmol·mg(-1)·min(-1) (n = 4, P < 0.01) and decreased NCC activity from 75.4 ± 2.7 to 20.3 ± 1.3 nmol·mg(-1)·min(-1) (n = 4, P < 0.01). Knockdown of Ras guanyl-releasing protein (RasGRP)1 had no baseline effect on (45)Ca(2+) uptake but significantly attenuated the response to PTH from a 45% increase (6.0 ± 0.2 to 8.7 ± 0.4 nmol·mg(-1)·min(-1)) in control cells to only 20% in knockdown cells (6.1 ± 0.1 to 7.3 ± 0.2 nmol·mg(-1)·min(-1), n = 4, P < 0.01). Inhibition of PKC and PKA resulted in further attenuation of the PTH effect. RasGRP1 knockdown decreased the magnitude of the TRPV5 response to PTH (7.9 ± 0.1 nmol·mg(-1)·min(-1) for knockdown compared with 9.1 ± 0.1 nmol·mg(-1)·min(-1) in control), and the addition of thiazide eliminated this effect (a nearly identical 9.0 ± 0.1 nmol·mg(-1)·min(-1)). This indicates that functionally active NCC is required for RasGRP1 knockdown to impact the PTH effect on TRPV5 activity. Knockdown of with no lysine kinase (WNK)4 resulted in an attenuation of the increase in PTH-mediated TRPV5 activity. TRPV5 activity increased by 36% compared with 45% in control (n = 4, P < 0.01 between PTH-treated groups). PKC blockade further attenuated the PTH effect, whereas combined PKC and PKA blockade in WNK4KD cells abolished the effect. We conclude that modulation of NCC activity contributes to the response to PTH, implying a role for hormonal modulation of NCC activity in distal Ca(2+) handling.

Economic evaluation of single-pill combination of indapamide and amlodipine in the treatment of arterial hypertension in the Polish setting.

PubMed

Kawalec, Paweł; Holko, Przemysław; Stawowczyk, Ewa; Borowiec, Łukasz; Filipiak, Krzysztof J

2015-01-01

Arterial hypertension is a common disorder that affects around 9 million adults in Poland. Single-pill combinations (SPCs) for the treatment of arterial hypertension have significant advantages over the free combinations, resulting in lower risk of cardiovascular events and lower consumption of medical resources. The current ESC/ESH 2013 guidelines for the first time recommend treatment with a combination of thiazide-like diuretic with calcium channel blocker. Currently, no such combination is reimbursed from public funds in Poland. To assess the economic value of treatment with SPC of indapamide and amlodipine (Tertens-AM®) for hypertensive patients compared with free combination therapy (FC), in the Polish setting. As there are currently no published data directly estimating the additional effect of using indapamide + amlo-dipine SPC vs. FC, two extreme approaches are presented: with difference in effectiveness due to improved adherence to the treatment estimated from published studies on other molecules used in hypertension such as SPCs and FCs - the base-case approach (1); and assuming no difference of effectiveness or adherence between SPC and FC of indapamide and amlodipine - the conservative approach (2). Modelling was carried out based on the Markov process in lifetime horizon. In the base-case approach, with the difference in effectiveness between SPC and FC, it was assumed that the differences in compliance translate into the differences in systolic blood pressure. Patients' characteristics were correlated with the risk of events associated with cardiovascular disease, based on the prediction algorithms from the Framingham Heart Study. Costs were considered from a National Health Fund (NHF) perspective and NHF and patient's perspective, and therefore direct medical costs were only included. The treatment with SPC of indapamide and amlodipine in place of FC resulted in 7.6 additional days of life in full health and longer overall patient survival by 2.9 days. The replacement of FC with SPC would result in national savings from both NHF perspective and NHF and patient's perspective, irrespective of the assumption of the difference in adherence between SPC and FC. The savings would amount to 1.602-3.954 million PLN and 16.498-19.186 million PLN from NHF perspective and NHF and patient's perspective, respectively. The treatment with SPC of indapamide and amlodipine for hypertensive patients was found to be dominant over FC or at least less expensive than treatment with FC when the difference in effectiveness was neglected. The replacement of FC with SPC would result in savings from both NHF perspective and NHF and patient's perspective.

Pharmacokinetic study of single- and multiple-dosing with metolazone tablets in healthy Chinese population.

PubMed

Li, Xueqing; Wang, Rutao; Liu, Yang; Liu, Yun; Zheng, Heng; Feng, Yabo; Zhao, Na; Geng, Hongbin; Zhang, Wanzhi; Wen, Aidong

2017-11-16

Metolazone is a diuretic, saluretic and antihypertensive chemical compound from the quinazoline category that possesses medicinal features similar to those of other thiazide diuretic drugs. However, the pharmacokinetics of metolazone in the Chinese population has rarely been studied. This study aimed to examine the pharmacokinetic characteristics, safety characteristic, and tolerability of metolazone in healthy Chinese subjects after single and multiple doses taken orally as well as the effects that food and gender have on oral metolazone pharmacokinetic parameters. An open-label, randomized, and single- and multiple-dosing investigation was performed in healthy Chinese subjects. The investigation included 3 study groups: the 0.5 mg, 1 mg and 2 mg dose groups were the single-dose study groups in the first stage. Eligible volunteers were randomly and orally administered a single 0.5 mg, 1 mg, or 2 mg metolazone tablet. The 0.5 mg dose group was also part of the multiple-dose study group, and the 1 mg dose group was the food-effect study group in the second stage. Human plasma samples were gathered pre-dosing and up to 48 h after dosing. The human plasma sample concentration of metolazone was quantified using a validated liquid chromatography tandem mass spectrometry method. Pharmacokinetic data were calculated by a noncompartmental analysis method using WinNonlin version 6.4. Tolerability was evaluated based on adverse events, medical examination, 12-lead ECG, and other clinical laboratory exams. Thirty eligible subjects (15 men and 15 women) were registered in our investigation and completed all of the study stages. The AUC and C max showed dose proportionality after a single dose based on the linear-regression analysis. A comparison of the pharmacokinetic data revealed that the differences between the male and female groups were not statistically significant. The t max of metolazone was increased by approximately 100% in the fed condition. Metolazone was well tolerated at the tested dose, and no adverse effects were observed. Single dosing with 0.5 mg, 1 mg, or 2 mg metolazone yielded linear plasma pharmacokinetic properties in healthy Chinese subjects. Multiple oral doses of metolazone did not display significantly different distributions or elimination characteristics from those observed for a single dose. Gender factors did not appear to influence the pharmacokinetic parameter variation of metolazone. The t max of metolazone increased in the fed condition. Metolazone was well tolerated at the tested dose in this study. This investigation is retrospectively registered at chictr.org.cn (ChiCTR-IIR-17012929, October 09 2017).

International comparison of cost effectiveness of medical management strategies for nephrolithiasis.

PubMed

Lotan, Yair; Cadeddu, Jeffrey A; Pearle, Margaret S

2005-06-01

Although medical therapy is known to reduce the risk of kidney stone recurrence, the cost effectiveness of medical prophylaxis is controversial. We evaluated medical treatment strategies including dietary measures (conservative), empiric medical therapy (empiric) or directed medical therapy (directed) based on comprehensive metabolic evaluation (CME) for patients with recurrent kidney stones, and compared the costs of these strategies using cost data from ten different countries. We previously established rates of stone formation in recurrent stone-formers, risk reduction of medical therapy, sensitivity of CME and rates of spontaneous stone passage from a comprehensive literature search (Lotan et al. 2004 J Urol 172: 2275). The costs of medication, surgical therapy, emergency room visits and CME for ten different countries were obtained from a published report of an international cost survey (Chandhoke 2002 J Urol 168: 937) as well as from our own county hospital in the US. Medication costs in the US were obtained from two national pharmacy chains. A decision tree model was created to compare the costs of different treatment strategies assuming cost accrual for metabolic evaluation, medical therapy and surgery or emergency room visits. For medical therapy, we assumed the distribution of medication use described in the published report, consisting of potassium citrate (60%), thiazide (30%) and allopurinol (10%). A nearly 20-fold difference in the costs of shock-wave lithotripsy, ureteroscopy and medication was found among different countries. From the model (US dollars/patient/year), conservative therapy alone was the most cost effective approach followed by empiric and directed medical therapy in all countries except in the UK. In the UK, the cost of drug therapy (estimated at dollar 29/patient/year) resulted in empiric therapy being the most cost effective strategy for recurrent stone formers. The low likelihood of surgical intervention, as well as the low relative cost of surgery to medication, contributed to the higher cost of empiric and directed medical therapy strategies. Of note, despite the higher cost, drug treatment strategies were associated with significantly lower stone recurrence rates. We found that drug treatment strategies are more costly than conservative treatment but produce good control of stone formation. In all but one country (UK), dietary therapy was the most cost effective approach due to the relatively low cost of surgery compared with medication. The differential resource allocation to different components of a healthcare system (i.e. subsidized medication versus surgical treatment) in different countries determines the cost effectiveness of various treatment strategies.

Effectiveness of the selective aldosterone blocker, eplerenone, in patients with resistant hypertension.

PubMed

Calhoun, David A; White, William B

2008-01-01

Resistant hypertension is defined as uncontrolled hypertension despite intensive treatment with at least three antihypertensive agents, one of which ideally should be a diuretic. To determine the efficacy and safety of the selective aldosterone antagonist eplerenone in this population, we studied patients with resistant hypertension (clinic blood pressure [BP] >140 mm Hg systolic or >90 mm Hg diastolic on maximal doses of more than three antihypertensive agents, including a loop or thiazide diuretic). At baseline and after 12 weeks of eplerenone therapy (50 to 100 mg daily titrated to effect), patients underwent clinic and 24-hour BP measurements, serum potassium, plasma renin activity, and serum aldosterone measurements. Patients (n = 52) completing the trial averaged 62 +/- 10 years of age, were overweight (mean body mass index, 32.1 +/- 5.5 kg/m(2)), and had variable renal function (glomerular filtration rate, 106 +/- 38 mL/minute); 70% were men and 74% were non-Black. The mean number of antihypertensive agents at baseline was 3.7 +/- 0.8 (range, three to seven drugs) to achieve a clinic BP of 150.5/84.1 mm Hg. The mean serum aldosterone was 12.9 +/- 7.6 ng/mL and plasma renin activity was 2.3 +/- 2.7 ng/mL/hour. After eplerenone, the change from baseline in the clinic BP was -17.6/-7.9 mm Hg (P < .0001 for both systolic blood pressure [SBP] and diastolic blood pressure [DBP]) and in 24-hour BP was -12.2/-6.0 mm Hg (P < .0001 for both). The number of antihypertensive drugs decreased to 3.3 +/- 0.9 (range, one to seven agents). Plasma potassium increased by 0.30 +/- 0.45 mEq/L (P < .001), but there were only three instances in two patients of mild hyperkalemia (potassium >5.5 mEq/L, but <6.0 mEq/L), despite all patients being on a background therapy that included an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. Reductions in clinic and ambulatory BP were related to baseline clinic and ambulatory BP values (r(2) > 0.3 for both SBP and DBP, P < .0001), weakly related to baseline serum aldosterone (r = -0.30; P = .05), and unrelated to plasma renin activity, age, gender, or race. In conclusion, eplerenone demonstrated substantial efficacy in treatment-resistant hypertension and was well-tolerated with modest changes in plasma potassium. Serum aldosterone and plasma renin activity did not predict BP responses to eplerenone in this population.

Different antihypertensive effect of beta-blocking drugs in low and normal-high renin hypertension.

PubMed

Kralberg, B E; Tolagen, K

1976-05-31

The treatment response to beta-adrenoceptor blocking drugs was compared in two groups of patients with primary (essential) hypertension and different renin levels. Each group consisted of 25 patients and was equally distributed regarding age, severity and stage of hypertension. In the first group (group 1), the mean upright plasma renin activity was 0.8 ng ml-1h-1 (range 0.3 to 1.5) and the patients were considered to have low renin hypertension. In the other group (group 2) the patients had a mean plasma renin activity of 2.1 ng ml-1h-1 (range 1.1 to 5.1) and were considered to have normal to high renin hypertension. In both groups the patients were initially treated with beta-blocking drugs; in group 1 with a beta-blocker corresponding to an average dose of 311 mg propranolol a day for at least eight weeks and in group 2 with propranolol 320 mg a day in a fixed dose for eight weeks. The hypotensive response differed significantly between the two groups (p less than 0.001). In group 1 the pretreatment blood pressure was 197/117 mm Hg supine and 198/120 mm Hg standing. During treatment blood pressure decreased only 5/3 mm Hg supine and 9/5 mm Hg standing. The pretreatment blood pressure in group 2 was 187/114 mm Hg supine and 186/117 mm Hg standing. Beta-blocking therapy reduced blood pressure 36/23 and 34/18 mm Hg, respectively (both p less than 0.001). Pulse rates fell significantly in the two groups, both in the lying and standing positions. In 17 patients with low renin hypertension (group 1), a volume-depleting drug was added (spironolactone, 14 patients; thiazides, 3 patients) and this achieved a marked fall in blood pressure levels of 38/16 mm Hg supine and 37/19 mm Hg standing (both p less than 0.001). These results suggest the following: (1) Most patients with normal to high plasma renin activity respond well to moderate doses of propranolol. (2) Propranolol given in the same doses is almost without antihypertensive effect in patients with low renin hypertension. (3) A volume factor may be operating in patients with low renin hypertension since a hypotensive effect is demonstrated after the addition of volume-depleting drugs. (4) Determination of plasma renin activity with adequate methods can predict the treatment response to hypotensive agents.

Assessing pharmacokinetic interactions between the sodium glucose cotransporter 2 inhibitor empagliflozin and hydrochlorothiazide or torasemide in patients with type 2 diabetes mellitus: a randomized, open-label, crossover study.

PubMed

Heise, Tim; Mattheus, Michaela; Woerle, Hans J; Broedl, Uli C; Macha, Sreeraj

2015-04-01

Empagliflozin is a potent, selective sodium glucose cotransporter 2 inhibitor approved for the treatment of type 2 diabetes mellitus. Thiazide or loop diuretics are commonly prescribed in patients with type 2 diabetes mellitus. This study investigated potential pharmacokinetic drug-drug interactions between empagliflozin and hydrochlorothiazide (HCTZ) or torasemide (TOR). This was an open-label, crossover study. Patients with type 2 diabetes mellitus were randomized to receive empagliflozin 25 mg once daily for 5 days and either HCTZ 25 mg once daily for 4 days followed by HCTZ 25 mg once daily plus empagliflozin 25 mg once daily for 5 days or TOR 5 mg once daily for 4 days followed by TOR 5 mg once daily plus empagliflozin once daily for 5 days in 1 of 4 sequences, with at least a 7-day washout period between treatments. Pharmacokinetic parameters of empagliflozin, HCTZ, and TOR were assessed and standard bioequivalence criteria (80%-125%) were applied. Tolerability assessments included the frequency of adverse events and an investigator assessment of global tolerability. Mean (SD) age of the 22 patients treated was 54.0 (8.1) years and body mass index was 27.1 (3.7) kg/m(2). Coadministration of empagliflozin with HCTZ or TOR had no effect on exposure to empagliflozin, HCTZ, or TOR. Geometric mean ratios (90% CIs) for empagliflozin AUC over a uniform dosing interval and Cmax at steady state were 107.1% (90% CI, 97.1-118.1) and 102.8% (90% CI, 88.6-119.3), respectively, when coadministered with HCTZ versus administration alone, and 107.8% (90% CI, 100.1-116.1) and 107.5% (90% CI, 97.9-118.0), respectively, when coadministered with TOR versus administration alone. For HCTZ, the geometric mean ratios for AUC over a uniform dosing interval and Cmax at steady state were 96.3% (90% CI, 89.1-104.0) and 101.8% (90% CI, 88.6-116.9), respectively, and for TOR were 101.4% (90% CI, 99.1-103.9) and 104.4% (90% CI, 93.8-116.3), respectively, for combined treatment versus administration alone. The pharmacokinetic profiles of empagliflozin, HCTZ, and TOR were similar after administration alone and in combination. Global tolerability was good for all patients after each treatment, and no severe or serious adverse events were reported. No pharmacokinetic drug-drug interaction was observed between empagliflozin and HCTZ or TOR. ClinicalTrials.gov identifier: NCT01276288. Copyright © 2015 Elsevier HS Journals, Inc. All rights reserved.

Effect of combination therapy with the angiotensin receptor blocker losartan plus hydrochlorothiazide on brain perfusion in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic major cerebral artery steno-occlusive disease: a SPECT study.

PubMed

Saura, Hiroaki; Ogasawara, Kuniaki; Suzuki, Taro; Kuroda, Hiroki; Yamashita, Takeshi; Kobayashi, Masakazu; Terasaki, Kazunori; Ogawa, Akira

2012-01-01

While the combination of an angiotensin receptor blocker with thiazide diuretics produces a clinically beneficial reduction in blood pressure in patients who otherwise only partially respond to monotherapy with an angiotensin receptor blocker, blood pressure-lowering therapy with combination antihypertensive drug regimens in patients with cerebral hemodynamic impairment may adversely affect cerebral hemodynamics. The purpose of the present exploratory study was to determine whether blood pressure-lowering therapy with the combination of the angiotensin receptor blocker losartan plus hydrochlorothiazide (LPH) worsens brain perfusion in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic major cerebral artery steno-occlusive disease. Patients with losartan-resistant hypertension and reduced cerebrovascular reactivity (CVR) to acetazolamide due to symptomatic chronic internal carotid artery (ICA) or middle cerebral artery (MCA) steno-occlusive disease were prospectively entered into the present study and received 50 mg/day of losartan plus 12.5 mg/day of hydrochlorothiazideat 14 weeks after the last ischemic event. Cerebral blood flow (CBF) and CVR were measured before and 12 weeks after initiating LPH using N-isopropyl-p-[(123)I]-iodoamphetamine single-photon emission computed tomography (SPECT). A region of interest (ROI) was automatically placed in the MCA territory on each SPECT image using a three-dimensional stereotactic ROI template. None of the 18 patients who participated in the study experienced any new neurological symptoms or adverse effects related to antihypertensive drugs. Systolic (p < 0.001) and diastolic (p < 0.001) blood pressures were significantly reduced after the administration of LPH, with average reductions of 11 mm Hg in systolic blood pressure and 10 mm Hg in diastolic blood pressure. While in the affected hemisphere CBF did not differ between measurements taken before and after the administration of LPH, CVR was significantly higher after the administration of LPH than before (p = 0.007) and was significantly improved in 5 of 18 patients. In the contralateral hemisphere, CBF and CVR did not differ between measurements taken before and after the administration of LPH. There were no patients who experienced a significant deterioration in CBF or CVR in the affected or contralateral hemisphere after the administration of LPH. Although the present study was exploratory and its results were preliminary due to the small sample size, the current data suggest that blood pressure-lowering therapy with LPH apparently does not result in worsening of cerebral hemodynamics in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic ICA or MCA steno-occlusive disease. Copyright © 2012 S. Karger AG, Basel.

Poverty is a risk factor for osteoporotic fractures.

PubMed

Navarro, M C; Sosa, M; Saavedra, P; Lainez, P; Marrero, M; Torres, M; Medina, C D

2009-03-01

This study assesses the possible association between poverty and osteoporosis and/or fragility fractures in a population of postmenopausal women. We found that postmenopausal women with low socioeconomic status had lower values of BMD at the lumbar spine, a higher prevalence of densitometric osteoporosis, and a higher prevalence of total and vertebral fractures. Some lifestyles are related to the presence of osteoporosis and/or fragility fractures, whereas poverty is related to some lifestyles. Because of this, we studied the possible association of poverty with osteoporosis and fractures. This was an observational, cross-sectional study performed in the Canary Islands, Spain. Participants consisted of a total of 1,139 ambulatory postmenopausal women aged 50 years or older with no previous osteoporosis diagnosis and who were enrolled in some epidemiological studies. The prevalence of fractures (vertebral and non-vertebral) and the prevalence of osteoporosis (T-score <-2.5 either at the lumbar spine or the femoral neck). A previously validated questionnaire elicited the most important risk factors for osteoporosis: socioeconomic status, defined by the annual income was also assessed by a personal interview. A dorso-lateral X-ray of the spine was performed, and bone mineral density (BMD) was measured by DXA in the lumbar spine (L2-L4) and proximal femur. Compared to women with a medium and high socioeconomic status (n = 665), those who were classified into poverty (annual family income lower than 6,346.80 Euros, in a one-member family, n = 474), were older and heavier and had lower height, lower prevalence of tobacco and alcohol consumption, lower use of HRT and higher use of thiazides. After correcting for age and body mass index (BMI), women in poverty had lower spine BMD values than women with a medium and high socioeconomic status (0.840 g/cm(2) vs. 0.867 g/cm(2), p = 0.005), but there were no statistical differences in femoral neck BMD between groups. The prevalence of osteoporosis was also higher in women in poverty [40.6% vs. 35.6%, (OR 1.35, CI 95%: 1.03; 1.76)] after adjusting by age and BMI. Moreover, 37.8% of women in poverty had a history of at least one fragility fracture compared to 27.7% of women not in poverty (OR: 1.45, CI 95%: 1.11; 1.90). The prevalence of vertebral fractures was also higher in women in poverty 24.7% vs. 13.4%, (OR 2.01, CI 95%: 1.44; 2.81). Postmenopausal women with low socioeconomic status had lower values of BMD at the lumbar spine, and a higher prevalence of densitometric osteoporosis, and a higher prevalence of total and vertebral fractures. Because of this, apart from the well known risk factors for osteoporosis, poverty should be taken into account as a possible risk factor for both osteoporosis and fragility fractures, in order to establish sanitary strategies to protect unfavoured postmenopausal women.

First-line drugs inhibiting the renin angiotensin system versus other first-line antihypertensive drug classes for hypertension.

PubMed

Xue, Hao; Lu, Zhuang; Tang, Wen Lu; Pang, Lu Wei; Wang, Gan Mi; Wong, Gavin W K; Wright, James M

2015-01-11

Renin-angiotensin system (RAS) inhibitors are widely prescribed for treatment of hypertension, especially for diabetic patients on the basis of postulated advantages for the reduction of diabetic nephropathy and cardiovascular morbidity and mortality. Despite widespread use of angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) for hypertension in both diabetic and non-diabetic patients, the efficacy and safety of RAS inhibitors compared to other antihypertensive drug classes remains unclear. To evaluate the benefits and harms of first-line RAS inhibitors compared to other first-line antihypertensive drugs in patients with hypertension. We searched the Cochrane Hypertension Group's Specialised Register, MEDLINE, MEDLINE In-Process, EMBASE and ClinicalTrials.gov for randomized controlled trials up to November 19, 2014 and the Cochrane Central Register of Controlled Trials (CENTRAL) up to October 19, 2014. The WHO International Clinical Trials Registry Platform (ICTRP) is searched for inclusion in the Cochrane Hypertension Group's Specialised Register. We included randomized, active-controlled, double-blinded studies with at least six months follow-up in people with primary elevated blood pressure (≥130/85 mmHg), which compared first-line RAS inhibitors with other first-line antihypertensive drug classes and reported morbidity and mortality or blood pressure outcomes. Patients with proven secondary hypertension were excluded. Two authors independently selected the included trials, evaluated the risk of bias and entered the data for analysis. We included 42 studies, involving 65,733 participants, with a mean age of 66 years. Much of the evidence for our key outcomes is dominated by a small number of large studies at a low risk of bias for most sources of bias. Imbalances in the added second-line antihypertensive drugs in some of the studies were important enough for us to downgrade the quality of the evidence.Primary outcomes were all-cause death, fatal and non-fatal stroke, fatal and non-fatal myocardial infarction (MI), fatal and non-fatal congestive heart failure (CHF) requiring hospitalization, total cardiovascular (CV) events (consisted of fatal and non-fatal stroke, fatal and non-fatal MI and fatal and non-fatal CHF requiring hospitalizations), and ESRF. Secondary outcomes were systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR).Compared with first-line calcium channel blockers (CCBs), we found moderate quality evidence that first-line RAS inhibitors decreased heart failure (HF) (35,143 participants in 5 RCTs, RR 0.83, 95% CI 0.77 to 0.90, ARR 1.2%), and moderate quality evidence that they increased stroke (34,673 participants in 4 RCTs, RR 1.19, 95% CI 1.08 to 1.32, ARI 0.7%). They had similar effects on all-cause death (35,226 participants in 5 RCTs, RR 1.03, 95% CI 0.98 to 1.09; moderate quality evidence), total CV events (35,223 participants in 6 RCTs, RR 0.98, 95% CI 0.93 to 1.02; moderate quality evidence), total MI (35,043 participants in 5 RCTs, RR 1.01, 95% CI 0.93 to 1.09; moderate quality evidence). The results for ESRF do not exclude potentially important differences (19,551 participants in 4 RCTs, RR 0.88, 95% CI 0.74 to 1.05; low quality evidence).Compared with first-line thiazides, we found moderate quality evidence that first-line RAS inhibitors increased HF (24,309 participants in 1 RCT, RR 1.19, 95% CI 1.07 to 1.31, ARI 1.0%), and increased stroke (24,309 participants in 1 RCT, RR 1.14, 95% CI 1.02 to 1.28, ARI 0.6%). They had similar effects on all-cause death (24,309 participants in 1 RCT, RR 1.00, 95% CI 0.94 to 1.07; moderate quality evidence), total CV events (24,379 participants in 2 RCTs, RR 1.05, 95% CI 1.00 to 1.11; moderate quality evidence), and total MI (24,379 participants in 2 RCTs, RR 0.93, 95% CI 0.86 to 1.01; moderate quality evidence). Results for ESRF do not exclude potentially important differences (24,309 participants in 1 RCT, RR 1.10, 95% CI 0.88 to 1.37; low quality evidence).Compared with first-line beta-blockers, we found low quality evidence that first-line RAS inhibitors decreased total CV events (9239 participants in 2 RCTs, RR 0.88, 95% CI 0.80 to 0.98, ARR 1.7%), and low quality evidence that they decreased stroke (9193 participants in 1 RCT, RR 0.75, 95% CI 0.63 to 0.88, ARR 1.7% ). Our analyses do not exclude potentially important differences between first-line RAS inhibitors and beta-blockers on all-cause death (9193 participants in 1 RCT, RR 0.89, 95% CI 0.78 to 1.01; low quality evidence), HF (9193 participants in 1 RCT, RR 0.95, 95% CI 0.76 to 1.18; low quality evidence), and total MI (9239 participants in 2 RCTs, RR 1.05, 95% CI 0.86 to 1.27; low quality evidence).Blood pressure comparisons between RAS inhibitors and other classes showed either no differences or small differences that did not necessarily correlate with the differences in the morbidity outcomes.In the protocol, we identified non-fatal serious adverse events (SAE) as a primary outcome. However, when we extracted the data from included studies, none of them reported total SAE in a manner that could be used in the review. Therefore, there is no information about SAE in the review. We found predominantly moderate quality evidence that all-cause mortality is similar when first-line RAS inhibitors are compared to other first-line antihypertensive agents. First-line thiazides caused less HF and stroke than first-line RAS inhibitors. The quality of the evidence comparing first-line beta-blockers and first-line RAS inhibitors was low and the lower risk of total CV events and stroke seen with RAS inhibitors may change with the publication of additional trials. Compared with first-line CCBs, first-line RAS inhibitors reduced HF but increased stroke. The magnitude of the reduction in HF exceeded the increase in stroke. The small differences in effect on blood pressure between the different classes of drugs did not correlate with the differences in the primary outcomes.

Evaluation and medical management of kidney stones in children.

PubMed

Tasian, Gregory E; Copelovitch, Lawrence

2014-11-01

We review the current literature on the diagnostic evaluation and dietary and pharmacological management of children with nephrolithiasis. We searched MEDLINE(®), Embase(®) and the Cochrane Library from their inceptions to March 2014 for published articles in English on kidney stones and therapy in children 0 to 18 years old. Based on review of the titles and abstracts, 110 of the 1,014 articles (11%) were potentially relevant to the diagnostic evaluation and medical management of nephrolithiasis in children. We summarized this literature and drew on studies performed in adult populations to augment areas in which no studies of sufficient quality have been performed in children, and to highlight areas in need of research. During the last 25 years the incidence of nephrolithiasis in children has increased by approximately 6% to 10% annually and is now 50 per 100,000 adolescents. Kidney stones that form during childhood have a similar composition to those that form in adulthood. Approximately 75% to 80% of stones are composed of predominantly calcium oxalate, 5% to 10% are predominantly calcium phosphate, 10% to 20% are struvite and 5% are pure uric acid. The recurrence rate of nephrolithiasis in patients with stones that form during childhood is poorly defined. Ultrasound should be used as the initial imaging study to evaluate children with suspected nephrolithiasis, with noncontrast computerized tomography reserved for those in whom ultrasound is nondiagnostic and the suspicion of nephrolithiasis remains high. Current treatment strategies for children with kidney stone disease are based largely on extrapolation of studies performed in adult stone formers and single institution cohort or case series studies of children. Tamsulosin likely increases the spontaneous passage of ureteral stones in children. Increased water intake and reduction of salt consumption should be recommended for all children with a history of kidney stones. Potassium citrate is a potentially effective medication for children with calcium oxalate stones and concomitant hypocitraturia, as well as children with uric acid stones. However, long-term compliance with therapy and the effect on decreasing stone recurrence in children are unknown. Based largely on efficacy in adult populations, thiazide diuretics should be considered in the treatment of children with calcium based stones and persistent hypercalciuria refractory to reductions in salt intake. The incidence of kidney stone disease in children is increasing, yet few randomized clinical trials or high quality observational studies have assessed whether dietary or pharmacological interventions decrease the recurrence of kidney stones in children. Collaborative efforts and randomized clinical trials are needed to determine the efficacy and effectiveness of alternative treatments for children with nephrolithiasis, particularly those with calcium oxalate stones and concomitant hypercalciuria and hypocitraturia. Additional areas in need of study are the optimal length of time for a trial of stone passage in children, the cost-effectiveness of medical expulsive therapy vs analgesics alone, and the size and location of stones for which medical expulsive therapy is most effective. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

What have we learned from the current trials?

PubMed

Abbott, Kevin C; Bakris, George L

2004-01-01

Even well-conducted randomized controlled trials can only reduce uncertainty, not eliminate it. The trials presented in this article all have gaps, and like many studies, some raise more questions than answers. A summary of the current trials, however, can be presented as follows. For patients with essential hypertension who are at high risk for cardiovascular disease, the use of diuretic therapy (excluding simultaneous use of ACE or CCB) resulted in outcomes at least equivalent to the use of either ACE or CCB without diuretics. Naturally, the dilemma for clinicians is that these drugs are most often used in combination with thiazide diuretics, as indicated by the RENAAL trial where 80% of ARB were used with diuretics in patients with type II diabetes and known nephropathy. The increased risk of heart failure observed with ACE and CCB in that trial may be relevant only to patients in whom diuretics were not also used. The study does raise important awareness, however, that ACE or CCB use without diuretic therapy is no better than diuretic therapy, and may be associated with higher risk of certain outcomes. A substantial number of patients with essential hypertension might achieve adequate blood pressure control with diuretic monotherapy. If so, that certainly has important implications for the cost of medical care in this country. For African Americans with essential hypertension, ACE may have advantages as a component of therapy in comparison with CCBs or beta-blockers, although diuretics should probably be the cornerstone of therapy for them and supported by the Seventh Joint National Committee. For patients with proteinuric renal disease, whether associated with diabetes or hypertension, it should be considered inappropriate to use DHP CCB as monotherapy in any setting, whether as part of a clinical trial or in clinical practice. These drugs should not be considered as ethical placebo arms in trials, most especially in diabetic nephropathy, nor should they be used without an ACE or ARB in patients with proteinuric renal disease in the absence of documented contraindications or intolerance to ACE, ARB, or non-DHP CCB (which are now considered second-line agents for proteinuric renal disease, and are acceptable placebo or comparison arms in clinical trials). For patients with type I diabetes, ACE remain the cornerstone of therapy. Because of recent RENAAL and IDNT trial results, the greatest benefit for slowing progression of renal disease in type II diabetic nephropathy now belongs to ARBs. In contrast, however, the HOPE trial showed that ACE, specifically ramipril, had the greatest evidence for prevention of cardiovascular outcomes in patients with renal insufficiency, regardless of diabetic status. Cardiovascular outcomes were secondary end points in the RENAAL and IDNT trials, and with the exception of heart failure for losartan, no benefits on cardiovascular outcomes were statistically significant. Progression of renal disease has only been studied in a relatively small cohort of Israeli patients comparing enalapril with nifedipine. These gaps lead to a classic dilemma in medical decision-making. Because evidence has shown that patients with elevated serum creatinine (greater than or equal to 1.4 mg/dL) are just as likely to die from cardiovascular disease as they are to reach end-stage renal disease, which outcome should be the focus for clinicians, or for researchers? Using a strictly evidence-based approach, this question can only be answered by yet another large, long, randomized, controlled trial. Given the similarity of actions between the ARB and ACE, it is likely there is considerable overlap of both benefits and side-effects between the two, although ARB may have a lower incidence of cough and hyperkalemia. The decision of which antihypertensive agents to use will have to be tailored carefully to the needs of the patient and careful consideration of both medical and economic factors. Regardless of the choice between an ACE or ARB, however, post hoc analysis of clinical trials [21,47] and observational data clearly indicate that patients with chronic kidney disease, even if considered mild (ie, serum creatinine greater than or equal to 1.4 mg/dL) are at significantly greater risk of cardiovascular morbidity and mortality compared with those with better kidney function. As stated in a recent review by the authors of the HOPE trial [50], "the frequent practice of withholding ACE [or ARB] in patients with mild renal insufficiency is unwarranted," because not only are these patients precisely those who might benefit most from their use, but safety and tolerability are generally excellent. Based on the results of the AASK trial, the authors add the same for the use of ACE inhibitors in African Americans.

Beta-blockers for hypertension.

PubMed

Wiysonge, C S; Bradley, H; Mayosi, B M; Maroney, R; Mbewu, A; Opie, L H; Volmink, J

2007-01-24

Two recent systematic reviews found first-line beta-blockers to be less effective in reducing the incidence of stroke and the combined endpoint of stroke, myocardial infarction, and death compared to all other antihypertensive drugs taken together. However, beta-blockers might be better or worse than a specific class of drugs for a particular outcome measure so that comparing beta-blockers with all other classes taken together could be misleading. In addition, these systematic reviews did not assess the tolerability of beta-blockers relative to other antihypertensive medications. We thus undertook this review to re-assess the place of beta-blockade as first-line therapy for hypertension relative to each of the other major classes of antihypertensive drugs. To quantify the effectiveness and safety of beta-blockers on morbidity and mortality endpoints in adults with hypertension. We searched eligible studies up to June 2006 in the Cochrane Controlled Trials Register, Medline, Embase, and reference lists of previous reviews, and by contacting hypertension experts. We selected randomised controlled trials which assessed the effectiveness of beta-blockers compared to placebo, no therapy or other drug classes, as monotherapy or first-line therapy for hypertension, on mortality and morbidity endpoints in men and non-pregnant women aged 18 years or older. At least two authors independently applied study selection criteria, assessed study quality, and extracted data; with differences resolved by consensus. We expressed study results as relative risks (RR) with 95% confidence intervals (CI) and conducted quantitative analyses with trial participants in groups to which they were randomly allocated, regardless of which or how much treatment they actually received. In the absence of significant heterogeneity between studies (p>0.1), we performed meta-analysis using a fixed effects method. Otherwise, we used the random effects method and investigated the cause of heterogeneity by stratified analysis. In addition, we used the Higgins statistic (I(2)) to quantify the amount of between-study variability in effect attributable to true heterogeneity rather than chance. Thirteen randomised controlled trials (N=91,561 participants), which met our inclusion criteria, compared beta-blockers to placebo or no treatment (4 trials with 23,613 participants), diuretics (5 trials with 18,241 participants), calcium-channel blockers (CCBs: 4 trials with 44,825 participants), and renin-angiotensin system (RAS) inhibitors (3 trials with 10,828 participants). The risk of all-cause mortality was not different between first-line beta-blockers and placebo (RR 0.99, 95%CI 0.88 to 1.11, I(2)=0%), diuretics or RAS inhibitors, but was higher for beta-blockers compared to CCBs (RR 1.07, 95%CI 1.00 to 1.14, I(2)=2.2%; ARI=0.5%, NNH=200). The risk of total cardiovascular disease (CVD) was lower for first-line beta-blockers compared to placebo (RR 0.88, 95%CI 0.79 to 0.97, I(2)=21.4%, ARR=0.7%, NNT=140). This is primarily a reflection of the significant decrease in stroke (RR 0.80, 95%CI 0.66 to 0.96; I(2)=0%; ARR=0.5%, NNT=200); coronary heart disease (CHD) risk was not significantly different between beta-blockers and placebo. The effect of beta-blockers on CVD was significantly worse than that of CCBs (RR 1.18, 95%CI 1.08 to 1.29, I(2)=0%; ARI=1.3%, NNH=80), but was not significantly different from that of diuretics or RAS inhibitors. Increased total CVD was due to an increase in stroke compared to CCBs (RR 1.24, 95%CI 1.11 to 1.40, I(2)=0%; ARI=0.6%, NNH=180). There was also an increase in stroke with beta-blockers as compared to RAS inhibitors (RR 1.30, 95%CI 1.11 to 1.53, I(2)=29.1%; ARI=1.5%, NNH=65). CHD was not significantly different between beta-blockers and diuretics or CCBs or RAS inhibitors. In addition, patients on beta-blockers were more likely to discontinue treatment due to side effects than those on diuretics (RR 1.86, 95%CI 1.39 to 2.50, I(2)=78.2%, ARI=6.4% NNH=16) and RAS inhibitors (RR 1.41, 95%CI 1.29 to 1.54, I(2)=12.1%; ARI=5.5%, NNH=18), but there was no significant difference with CCBs. The available evidence does not support the use of beta-blockers as first-line drugs in the treatment of hypertension. This conclusion is based on the relatively weak effect of beta-blockers to reduce stroke and the absence of an effect on coronary heart disease when compared to placebo or no treatment. More importantly, it is based on the trend towards worse outcomes in comparison with calcium-channel blockers, renin-angiotensin system inhibitors, and thiazide diuretics. Most of the evidence for these conclusions comes from trials where atenolol was the beta-blocker used (75% of beta-blocker participants in this review). However, it is not known at present whether beta-blockers have differential effects on younger and elderly patients or whether there are differences between the different sub-types of beta-blockers.

Knowledge about Ultraviolet Radiation Hazards and Tanning Behavior of Cosmetology and Medical Students.

PubMed

Zuba, Ewelina Bogumiła; Francuzik, Wojciech; Malicki, Przemysław; Osmola-Mańkowska, Agnieszka; Jenerowicz, Dorota

2016-04-01

Dear Editor, Ultraviolet (UV) radiation is a well-known physical hazard responsible for photoaging, photoallergic, and phototoxic reactions as well as carcinogenesis, including life-threatening melanomas (1,2). Overexposure to both natural and artificial UV radiation is a public health concern. 30% of cancers diagnosed worldwide are skin cancers. Approximately three million non-melanoma skin cancers and 132 000 new cases of melanomas are diagnosed globally each year (3). Sunburns, especially in childhood, are a very important risk factor for melanomas. Several studies demonstrated a positive association between sunbed use and an increased incidence of malignant melanoma (4). Current medical and cosmetology students will soon be knowledge providers about the risks of excessive exposure to UV radiation and prophylaxis of its consequences. Our aim was to evaluate their knowledge about the side effects of ultraviolet radiation and tanning behaviors. Details on the knowledge and habits of students were obtained during classes at the Poznan University of Medical Sciences. With approval from the Institutional Bioethical Committee, a 41-question anonymous survey was conducted in the spring of 2012 among 190 medical (1-6 year) and cosmetology students (1-5 year). The mean age of the study group was 22.3 years (standard deviation (SD) = 2.4 years), range 19-28 years. The survey was composed of closed and open-ended questions prepared by the authors. The first part of the form included demographic data: gender, age, degree course, and school year. The students were also asked about their reaction to sunlight, sunburns in childhood, and personal and family history of skin cancers or dysplastic nevus syndrome. The factual section of the survey contained questions evaluating responder knowledge about sunbeds and risk of UV radiation as well as their personal tanning habits. The open-ended questions asked responders to provide definitions of: skin phototype, sun protection factor (SPF), and tanorexia. The students were additionally asked to mention possible side effects of solar radiation and contraindications to sunbeds and drugs, which may induce photosensitivity. Statistical analysis was performed using The R Project for Statistical Computing. Chi-squared test was used to compare both sun-risk knowledge and tanning behaviors between medical and cosmetology students. P<0.05 was considered statistically significant. We distributed 220 questionnaires and received 190 (86%) eligible for evaluation. Table 1 shows the study population. Gender distribution among groups was uneven, with significantly more male subjects in the medicine program group. We decided to include their answers in this study to provide an unbiased view of both of those programs. Where appropriate, we additionally provided comparisons between female subjects in both groups to prove that differences were not solely due to uneven gender distribution. When we asked students to define skin phototype, cosmetology students more frequently gave a correct definition. In the group of students who stated they knew the definition of skin phototype, medical students were significantly more frequently wrong when we asked them to explain the term in their own words. Cosmetology students correctly answered significantly more knowledge checking questions (Table 2). When we asked students to list photosensitizing agents, students of the cosmetology program gave twice as many correct answers per respondent as students of the medicine program (see Table 3). Cosmetology students more frequently listed retinoids, while medical students listed tetracyclines as the main photosensitizing drug. The most common answer in the cosmetology group was the herb of Hypericum perforatum, although it is not considered a drug. Psoralens were identified by only 4 medical students as a possible cause of phototoxicity. When students were asked to list adverse effects of sunbathing, we specifically looked for three responses (see Table 4). Cosmetology students listed those answers significantly more often than medical students. Students of the cosmetology program gave significantly more correct answers when asked to list contraindications for sunbathing. While medical students reported mainly pregnancy (as a contraindication for most medical procedures), cosmetology students reported history of skin cancer as the most frequent answer (Table 5). Cosmetology students (89.04%) stated they visited a tanning salon more often than medical students (46.55%) (P<0.0001). When we restricted this analysis to only female subjects there still was a significant difference (P=0.0002) between cosmetology and medical female students. Cosmetology students reported lower incidence of sunscreen use (83.78% vs. 97.39%; P=0.0019). The age of the first tanning studio visit was also lower for cosmetology students (mean = 16.5 years) than medical students (mean = 17.2 years), (P=0.0290). Figure 1 illustrates the frequency of student tanning studio visits; the difference between groups was significant (P=0.0308). Skin cancers, dysplastic nevi syndrome, and precancerous lesions were reported in the family history by 19 students (10.00%). 12 of those students (63.16%) were also tanning salons users. 85 students (44.74%) reported a history of a sunburn in their childhood and over half of them continue visiting tanning salons. Some American (5) and French (6) studies assessed medical student knowledge and behaviors concerning sun risk and its prevention. The results of these studies indicated that medical school students did not have a satisfactory awareness about sun risk hazards. The French evaluation showed medical student knowledge was comparable to that of the French general population. Studies evaluating Polish student knowledge (7-9) showed ignorance of the term Fitzpatrick's skin phototype. We emphasize this because patients with phototype 1 and 2 are more susceptible to the development of skin cancers (10) and ignorance in this matter may be dangerous. UV rays may promote drug-induced photosensitivity reactions such as phototoxicity and photoallergy (1), with the most common causes being: non-steroidal anti-inflammatory agents (ketoprofen, ibuprofen, piroxicam, diclofenac), cardiovascular drugs (furosemid, amiodarone, thiazides), antibiotics (tetracyclines, ciprofloxacine, sulfonamides), psoralens, and oral contraceptives (11). Our study found deficient knowledge about drugs which may trigger photosensitivity reactions. Cosmetology students reported significantly more risky tanning behavior but did better in knowledge checking questions, which may be explained by their personal interest in this subject or by educational focus due to their major. We suggest that better knowledge about sunbathing in general is due to increased interest in this matter (not solely due to formal education) and this interest derives from a positive attitude towards a tanned appearance. It has been proven that sunbathing shows signs of addictive behavior (12). Tanorexia as a term was more widely known among cosmetology students, which may illustrate that although students knew about the addictive properties of tanning, they were sure that this did not apply to them. Many studies showed that increased knowledge did not translate into safer tanning habits (13,14). Our study agrees with those findings. Our study demonstrated that medical and cosmetology student knowledge about sunbeds and risk of UV radiation is deficient. However, cosmetology students demonstrated better knowledge than medical students. Future cosmetologists may be better information providers about sun risk and its prevention. On the other hand, students of the cosmetology faculty tended to tan more often and longer and engage in more risky behavior despite being aware of the hazards of tanning. They may be more likely to develop skin cancers in the future.