About: Thiazide is a research topic. Over the lifetime, 2170 publications have been published within this topic receiving 62639 citations. The topic is also known as: thiazides & thiazide diuretic.
TL;DR: Thiazide-type diuretics are superior in preventing 1 or more major forms of CVD and are less expensive and should be preferred for first-step antihypertensive therapy.
Abstract: CONTEXT
Antihypertensive therapy is well established to reduce hypertension-related morbidity and mortality, but the optimal first-step therapy is unknown.
OBJECTIVE
To determine whether treatment with a calcium channel blocker or an angiotensin-converting enzyme inhibitor lowers the incidence of coronary heart disease (CHD) or other cardiovascular disease (CVD) events vs treatment with a diuretic.
DESIGN
The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), a randomized, double-blind, active-controlled clinical trial conducted from February 1994 through March 2002.
SETTING AND PARTICIPANTS
A total of 33 357 participants aged 55 years or older with hypertension and at least 1 other CHD risk factor from 623 North American centers.
INTERVENTIONS
Participants were randomly assigned to receive chlorthalidone, 12.5 to 25 mg/d (n = 15 255); amlodipine, 2.5 to 10 mg/d (n = 9048); or lisinopril, 10 to 40 mg/d (n = 9054) for planned follow-up of approximately 4 to 8 years.
MAIN OUTCOME MEASURES
The primary outcome was combined fatal CHD or nonfatal myocardial infarction, analyzed by intent-to-treat. Secondary outcomes were all-cause mortality, stroke, combined CHD (primary outcome, coronary revascularization, or angina with hospitalization), and combined CVD (combined CHD, stroke, treated angina without hospitalization, heart failure [HF], and peripheral arterial disease).
RESULTS
Mean follow-up was 4.9 years. The primary outcome occurred in 2956 participants, with no difference between treatments. Compared with chlorthalidone (6-year rate, 11.5%), the relative risks (RRs) were 0.98 (95% CI, 0.90-1.07) for amlodipine (6-year rate, 11.3%) and 0.99 (95% CI, 0.91-1.08) for lisinopril (6-year rate, 11.4%). Likewise, all-cause mortality did not differ between groups. Five-year systolic blood pressures were significantly higher in the amlodipine (0.8 mm Hg, P =.03) and lisinopril (2 mm Hg, P<.001) groups compared with chlorthalidone, and 5-year diastolic blood pressure was significantly lower with amlodipine (0.8 mm Hg, P<.001). For amlodipine vs chlorthalidone, secondary outcomes were similar except for a higher 6-year rate of HF with amlodipine (10.2% vs 7.7%; RR, 1.38; 95% CI, 1.25-1.52). For lisinopril vs chlorthalidone, lisinopril had higher 6-year rates of combined CVD (33.3% vs 30.9%; RR, 1.10; 95% CI, 1.05-1.16); stroke (6.3% vs 5.6%; RR, 1.15; 95% CI, 1.02-1.30); and HF (8.7% vs 7.7%; RR, 1.19; 95% CI, 1.07-1.31).
CONCLUSION
Thiazide-type diuretics are superior in preventing 1 or more major forms of CVD and are less expensive. They should be preferred for first-step antihypertensive therapy.
TL;DR: The amlodipine-based regimen prevented more major cardiovascular events and induced less diabetes than the atenolol- based regimen, and these effects might not be entirely explained by better control of blood pressure.
TL;DR: This study randomized 315 healthy volunteers in their early natural menopause to seven treatment and three placebo groups, with the aim of preventing postmenopausal bone loss.
Abstract: With the aim of preventing postmenopausal bone loss, a placebo-controlled double-blind trial of 2 years duration was performed. We randomized 315 healthy volunteers in their early natural menopause to seven treatment and three placebo groups: 17 beta-oestradiol, oestriol and sequential norethisteron (hormones); bendroflumethiazide 5 mg/day (thiazide); hormones and thiazide; sodium fluoride 20 mg/day; vitamin D3 2000 IU/day (D3); fluoride and D3; and 1 alpha (OH) vitamin D3 0.25 microgram/day (1 alpha D3). All participants were given daily calcium supplement of 500 mg. Every 3 months we measured the bone mineral content (BMC) of both forearms by photon absorptiometry and chemical quantities in blood and 48 h urinary collections. The study was completed by 264 (84%). The combined placebo groups showed a linear fall in BMC reaching 3.3% after 2 years (P < 0.001). Hormones and hormones and thiazide led to a 2.5% gain in BMC (P < 0.01). Thiazide alone postponed the BMC fall for 6 months. After 2 years the thiazide group showed a BMC fall of 1.5% (P < 0.05), less than that of the placebo group (P < 0.05). BMC declined by 3.6%, 4.5%, 3.7% and 3.7% during the respective use of fluoride, D3, fluoride and D3 and 1 alpha D3. Nevertheless, the urinary calcium excretion during 1 alpha D3 and D3 treatment was 1--1.5 mmol/day higher than in the placebo groups. Apparently, there is no real alternative to oestrogen/gestagen in the prevention of postmenopausal osteoporosis.
TL;DR: Antihypertensive treatment based on a beta-blocker or on a thiazide diuretic could not be shown to affect the prevention of hypertensive complications, including CHD, to a different extent.
Abstract: Men aged 40-64 years with mild to moderate hypertension [diastolic blood pressure (DBP) 100-130 mmHg] were randomized to treatment with a diuretic (n = 3272) or a beta-blocker (n = 3297), with additional drugs if necessary, to determine whether a beta-blocker based treatment differs from thiazide diuretic based treatment with regard to the prevention of coronary heart disease (CHD) events and death. Patients with previous CHD, stroke or other serious diseases, or with contraindications to diuretics or beta-blockers were excluded. If normotension (DBP less than 95 mmHg) was not achieved by monotherapy, other antihypertensive drugs were added, but the two basic drugs were not crossed over. Patients were assessed at 6-monthly intervals. The mean follow-up for end-points was 45.1 months. Blood pressure (BP) side effects and end-points were recorded in a standardized manner. Entry characteristics and the BP reduction achieved were very similar in both treatment groups. All analyses were made on an intention-to-treat basis. The incidence of CHD did not differ between the two treatment groups. The incidence of fatal stroke tended to be lower in the beta-blocker treated group than in the diuretic treated group. Total mortality and the total number of end-points were similar in both groups. The percentage of patients withdrawn due to side effects was similar, whereas the number of reported symptoms, according to a questionnaire, was higher for patients on beta-blockers. The incidence of diabetes did not differ between the two groups. Subgroup analyses did not detect a difference in the effect of beta-blockers compared with diuretics in smokers as opposed to non-smokers, and beta-blockers also had the same effects as diuretics in the quartile with the highest predicted risk for CHD. Beta-blockers and thiazide diuretics were approximately equally well tolerated. The two drugs had a similar BP reducing effect although additional drugs had to be given more often in the diuretic group. Antihypertensive treatment based on a beta-blocker or on a thiazide diuretic could not be shown to affect the prevention of hypertensive complications, including CHD, to a different extent.
TL;DR: It is shown that enhanced passive Ca2+ transport in the proximal tubule rather than active Ca2 + transport in distal convolution explains thiazide-induced hypocalciuria, and that Trpm6 downregulation may represent a general mechanism involved in the pathogenesis of hypomagnesemia accompanying NCC inhibition or inactivation.
Abstract: Thiazide diuretics enhance renal Na+ excretion by blocking the Na+-Cl- cotransporter (NCC), and mutations in NCC result in Gitelman syndrome. The mechanisms underlying the accompanying hypocalciuria and hypomagnesemia remain debated. Here, we show that enhanced passive Ca2+ transport in the proximal tubule rather than active Ca2+ transport in distal convolution explains thiazide-induced hypocalciuria. First, micropuncture experiments in mice demonstrated increased reabsorption of Na+ and Ca2+ in the proximal tubule during chronic hydrochlorothiazide (HCTZ) treatment, whereas Ca2+ reabsorption in distal convolution appeared unaffected. Second, HCTZ administration still induced hypocalciuria in transient receptor potential channel subfamily V, member 5-knockout (Trpv5-knockout) mice, in which active distal Ca2+ reabsorption is abolished due to inactivation of the epithelial Ca2+ channel Trpv5. Third, HCTZ upregulated the Na+/H+ exchanger, responsible for the majority of Na+ and, consequently, Ca2+ reabsorption in the proximal tubule, while the expression of proteins involved in active Ca2+ transport was unaltered. Fourth, experiments addressing the time-dependent effect of a single dose of HCTZ showed that the development of hypocalciuria parallels a compensatory increase in Na+ reabsorption secondary to an initial natriuresis. Hypomagnesemia developed during chronic HCTZ administration and in NCC-knockout mice, an animal model of Gitelman syndrome, accompanied by downregulation of the epithelial Mg2+ channel transient receptor potential channel subfamily M, member 6 (Trpm6). Thus, Trpm6 downregulation may represent a general mechanism involved in the pathogenesis of hypomagnesemia accompanying NCC inhibition or inactivation.