A randomized, comparative study evaluating the efficacy and tolerability of losartan-low dose chlorthalidone (6.25 mg) combination with losartan-hydrochlorothiazide (12.5 mg) combination in Indian patients with mild-to-moderate essential hypertension

Efficacy and safety of standard dose triple combination of telmisartan 80 mg/amlodipine 5 mg/chlorthalidone 25 mg in primary hypertension: A randomized, double-blind, active-controlled, multicenter phase 3 trial

The authors evaluated the efficacy, safety, and characteristics of patients who respond well to standard dose triple combination therapy including chlorthalidone 25 mg with telmisartan 80 mg plus amlodipine 5 mg in hypertensive patients. This is a multicenter, double-blind, active-controlled, phase 3, randomized trial. Patients are randomized to triple combination (telmisartan 40 mg/amlodipine 5 mg/chlorthalidone 12.5 mg, TEL/AML/CHTD group) or dual combination (telmisartan 40 mg/amlodipine 5 mg, TEL/AML group) treatment and then dose up titration to TEL 80/AML5/CHTD25mg and TEL80/AML5, respectively. The primary endpoint is the change of mean sitting systolic blood pressure (MSSBP) at week 8. A Target BP achievement rate, a response rate, and the safety endpoints are also evaluated. Total 374 patients (mean age = 60.9 ± 10.7 years, male = 78.3%) were randomized to the study. The baseline MSSBPs/diastolic BPs were 149.9 ± 12.2/88.5 ± 10.4 mm Hg. After 8 weeks treatment, the change of MSSBPs at week 8 are -19.1 ± 14.9 mm Hg (TEL/AML/CHTD) and -11.4 ± 14.7 mm Hg (TEL/AML) (p < .0001). The achievement rates of target BP (53.8% vs. 37.8%, p = .0017) and responder rate (54.8% vs. 35.6%, p = .0001) at week 8 were significantly higher in TEL/AML/CHTD. There are no serious adverse event and no one discontinued medication due to adverse event. Among the TEL 80/AML5/CHTD25mg treatment group, patients of female or age ≥ 65 years old showed higher rate of target BP achievement than relatively young male. (61.4 vs. 46.8%, p = .042) Our study showed standard dose triple combination of telmisartan 80 mg/amlodipine 5 mg/chlorthalidone 25 mg is efficacious and safe in treatment of primary hypertension. Target BP achievement with triple therapy would be facilitated in female or old age.

Comparison of the Effectiveness and Safety of Chlorthalidone and Hydrochlorothiazide in Patients With Hypertension: A Meta-Analysis

The aim of this study was to compare the effectiveness and safety of chlorthalidone and hydrochlorothiazide in patients with hypertension. The present meta-analysis was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Our search for relevant articles was conducted on PubMed, Scopus, and CINAHIL databases from their inception until March 31, 2023. Keywords used to search for relevant articles included "hydrochlorothiazide," "chlortalidone," "hypertension," "cardiovascular," and "blood pressure." The outcomes assessed in this meta-analysis included changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP). Myocardial infarction, stroke, and all-cause mortality were also assessed. For safety analysis, we evaluated the risk of hypokalemia between the two groups. Any disagreement between the two authors in the data extraction process was resolved through discussion. Eight studies fulfilled the inclusion criteria included in the present meta-analysis. Our analysis showed that chlorthalidone was superior to hydrochlorothiazide in controlling both SBP and DBP, with no significant heterogeneity reported. However, there was no significant difference between the two groups in terms of the risk of myocardial infarction, stroke, all-cause mortality, and hospitalization due to heart failure. The hypokalemia rate was reported to be higher with chlorthalidone compared to hydrochlorothiazide.

Chlorthalidone versus hydrochlorothiazide: major cardiovascular events, blood pressure, left ventricular mass, and adverse effects

BACKGROUND

There is continuous debate whether chlorthalidone (CTD) and hydrochlorothiazide (HCTZ) differ in reducing major cardiovascular events (MACE). HCTZ is prescribed 10 times more commonly than CTD.

METHOD

A systematic literature search yielded 14 references, including two network meta-analyses of randomized trials with MACE and left ventricular mass as outcomes.

RESULTS

The network meta-analysis of randomized trials showed CTD reducing MACE more than HCTZ, hazard ratio = 0.79 (0.72-0.88), P < 0.0001, and an observational cohort study gave an identical point estimate: hazard ratio = 0.79 (0.68-0.92), P = 0.002. In contrast, two observational cohort studies reported no differences between CTD and HCTZ. However, in the studies showing the superiority of CTD median follow-up was 4.3 and 7.0 years, respectively, whereas in the latter studies showing no difference between the two drugs follow-up was only 0.95 and 0.25 years. As differences in outcomes for MACE in hypertension trials with various interventions only emerge after prolonged (>1 year) therapy, differences in follow-up explain these discrepant results. CTD also more effectively reduced left ventricular mass in observational data and network analysis of trials. These advantages of CTD over HCTZ are consistent with greater reductions in night-time blood pressure, greater reductions in oxidative stress and platelet aggregation, and greater improvements in endothelial function.

CONCLUSION

Over the short-term there were no differences in the net clinical benefit between HCTZ and CTD. However, long-term available data document CTD to be significantly more effective in reducing MACE than HCTZ. The Veterans Administration's trial in progress may provide definitive answer to these questions.

Network meta-analysis of efficacy and safety of chlorthalidone and hydrochlorothiazide in hypertensive patients

Hypertension is a chronic condition leading to increased stress on the heart and blood vessels, a critical risk factor for clinically significant events such as myocardial infarction heart failure, stroke and death. Chlorthalidone and hydrochlorothiazide are first-line antihypertensive agents for most patients with hypertension. The aim of our meta-analysis was to compare the efficacy and safety of both therapies in patients with hypertension. Searches of electronic databases PubMed, MEDLINE, Scopus, PsycInfo and eLIBRARY.ru, were performed. We used network meta-analysis to combine direct and indirect evidence. Forest plots and closed loops depict estimated results from studies included in our meta-analysis. Of 1289 identified sources, only 37 were included in our meta-analysis. Our analysis has demonstrated a slight superiority for chlorthalidone regarding SBP and not statistically significant differences regarding DBP. Simultaneously, hydrochlorothiazide seems to be a safer choice of therapy, as evidenced by the levels of serum potassium. The two diuretics can be used interchangeably.

Angiotensin II type 1 receptor mediates pulmonary hypertension and right ventricular remodeling induced by inhaled nicotine

Use of electronic cigarettes is rapidly increasing among youth and young adults, but little is known regarding the long-term cardiopulmonary health impacts of these nicotine-containing devices. Our group has previously demonstrated that chronic, inhaled nicotine induces pulmonary hypertension (PH) and right ventricular (RV) remodeling in mice. These changes were associated with upregulated RV angiotensin-converting enzyme (ACE). Angiotensin II receptor blockers (ARBs) have been shown to reverse cigarette smoking-induced PH in rats. ACE inhibitor and ARB use in a large retrospective cohort of patients with PH is associated with improved survival. Here, we utilized losartan (an ARB specific for angiotensin II type 1 receptor) to further explore nicotine-induced PH. Male C57BL/6 mice received nicotine vapor for 12 h/day, and exposure was assessed using serum cotinine to achieve levels comparable to human smokers or electronic cigarette users. Mice were exposed to nicotine for 8 wk and a subset was treated with losartan via an osmotic minipump. Cardiac function was assessed using echocardiography and catheterization. Although nicotine exposure increased angiotensin II in the RV and lung, this finding was nonsignificant. Chronic, inhaled nicotine significantly increased RV systolic pressure and RV free wall thickness versus air control. These parameters were significantly lower in mice receiving both nicotine and losartan. Nicotine significantly increased RV internal diameter, with no differences seen between the nicotine and nicotine-losartan group. Neither nicotine nor losartan affected left ventricular structure or function. These findings provide the first evidence that antagonism of the angiotensin II type 1 receptor can ameliorate chronic, inhaled nicotine-induced PH and RV remodeling.NEW & NOTEWORTHY Chronic, inhaled nicotine causes pulmonary hypertension and right ventricular remodeling in mice. Treatment with losartan, an angiotensin II type 1 receptor antagonist, ameliorates nicotine-induced pulmonary hypertension and right ventricular remodeling. This novel finding provides preclinical evidence for the use of renin-angiotensin system-based therapies in the treatment of pulmonary hypertension, particularly in patients with a history of tobacco-product use.

Redefining diuretics use in hypertension: why select a thiazide-like diuretic?

Diuretics are listed in hypertension guidelines as one of three equally weighted first-line treatment options. In order to differentiate between antihypertensives, a lot of discussion has been directed at side effect profiles and as a result, has created a perhaps disproportionate fear of the metabolic effects that can be associated with diuretics. Data, however, show that the risk of a clinically meaningful change in laboratory parameters is very low, whereas the benefits of volume control and natriuresis are high and the reductions in morbidity and mortality are clinically significant. Moreover, as clinically significant differences in safety and efficacy profiles exist among diuretics, several international guidelines have started making a distinction between thiazides (hydrochlorothiazide) and thiazide-like (chlorthalidone, indapamide) diuretics; and some of them now recommend longer acting thiazide-like diuretics. In time, pending more data, chlorthalidone and indapamide may need to be subdivided further into separate classifications.

Comparative efficacy and safety of chlorthalidone and hydrochlorothiazide-meta-analysis

Hypertension is a complex syndrome of multiple hemodynamic, neuroendocrine, and metabolic abnormalities. The goals of treatment in hypertension are to optimally control high blood pressure and to reduce associated cardiovascular morbidity and mortality using the most suitable therapy available. Hydrochlorothiazide (HCTZ) and chlorthalidone (CTLD) are with proven hypertensive effects. The topic of our meta-analysis is to compare the efficacy of HCTZ and CTLD therapy in patient with hypertension. A search of electronic databases PubMed, MEDLINE, Scopus, PsyInfo, eLIBRARY.ru was performed. We chose the random-effects method for the analysis and depicted the results as forest plots. Sensitivity analyses were performed in order to evaluate the degree of significance of each study. Of the 1289 identified sources, only nine trials directly compared HCTZ and CTLD and were included in the meta-analysis. Changes in SBP lead to WMD (95% CI) equal to -3.26 mmHg showing a slight but statistically significant prevalence of CTLD. Results from analyzed studies referring to DBP lead to WMD (95% CI) equal to -2.41 mmHg, which is also statistically significant. During our analysis, we found that there were not enough studies presenting enough data on the effect of CTLD and HCTZ on levels of serum potassium and serum sodium. Our meta-analysis has demonstrated a slight superiority for CTLD regarding blood pressure control. At the same time, the two medications do not show significant differences in their safety profile.

Pharmacokinetic and pharmacodynamic considerations in the treatment of the elderly patient with hypertension

INTRODUCTION

Hypertension is an important risk factor for developing cardiovascular diseases. It is more prevalent in the elderly population. Recently updated American and European guidelines recommend treating every elderly patient with hypertension independent of age, starting with a low dose of antihypertensive drugs. However, little information is available on the optimal dosages of antihypertensive drugs to treat the elderly safely. Areas covered: Comorbidities, co-medication and frailty status can alter the clinical outcome of drug treatment and can cause adverse events in the elderly. Also, due to pharmacokinetic and pharmacodynamic changes the interpatient variability when using antihypertensive drugs is considerable. In this review, an overview is given on the extent to which the previously mentioned parameters are changed in elderly patients and what this means for the exposure to antihypertensive medication. Also, recommendations on the starting dose of the most frequently used antihypertensive drugs are given based on literature data. Expert opinion: We believe that recommendations on starting dosages followed by a stepwise increase of dosages will lead to improved blood pressure control and less adverse drug reactions in the elderly patient. This may improve adherence to antihypertensive therapy.

Chlorthalidone, not hydrochlorothiazide, is the right diuretic for comparison

We have read the study design "Comparison of effects between calcium channel blocker and diuretics in combination with angiotensin II receptor blocker on 24-h central blood pressure and vascular hemodynamic parameters in hypertensive patients: study design for a multicenter, double-blinded, active controlled, phase 4, randomized trial" by Oh GC, et al. with interest. The authors aim to compare the efficacy of amlodipine or hydrochlorothiazide (HCTZ) with an ARB. However, we wish to highlight that chlorthalidone (CTD) is the evidence-based and recommended anti-hypertensive diuretic, and should replace HCTZ in the trial to effectively compare efficacy against the CCB amlodipine.

Comparison of thiazide-like diuretics versus thiazide-type diuretics: a meta-analysis

Thiazide diuretics are widely used for the management of hypertension. In recent years, it has been actively debated that there is interchangeability of thiazide‐type diuretics hydrochlorothiazide and thiazide‐like diuretics including indapamide and chlorthalidone for the treatment of hypertension. With the purpose of seeking out the best thiazide diuretic for clinicians, we summarized the existing evidence on the two types of drugs and conducted a meta‐analysis on their efficacy in lowering blood pressure and effects on blood electrolyte, glucose and total cholesterol. Twelve trials were identified: five based on the comparison of indapamide versus hydrochlorothiazide and seven based on the chlorthalidone versus hydrochlorothiazide. In the meta‐analysis of blood pressure reduction, thiazide‐like diuretics seemed to further reduce systolic BP ([95% CI]; −5.59 [−5.69, −5.49]; P < 0.001) and diastolic BP ([95% CI]; −1.98 [−3.29, −0.66]; P = 0.003). Meanwhile, in the analysis of side effects, the incidence of hypokalemia ([95% CI]; 1.58 [0.80, 3.12]; P = 0.19), hyponatremia ([95% CI]; −0.14 [−0.57, 0.30], P = 0.54), change of blood glucose ([95% CI];0.13 [−0.16, 0.41], P = 0.39) and total cholesterol ([95% CI]; 0.13 [−0.16, 0.41], P = 0.39) showed that there is no statistical significant differences between the two groups of drugs. In conclusion, using thiazide‐like diuretics is superior to thiazide‐type diuretics in reducing blood pressure without increasing the incidence of hypokalemia, hyponatraemia and any change of blood glucose and serum total cholesterol.

Not just chlorthalidone: evidence-based, single tablet, diuretic alternatives to hydrochlorothiazide for hypertension

Accounting for 15 % of deaths worldwide, hypertension is often treated with hydrochlorothiazide (HCTZ) (50 million prescriptions annually). HCTZ has a <24-h duration of action, is less potent than chlorthalidone and all major antihypertensive drug classes, and is inferior to four antihypertensive drugs for cardiovascular event (CVE) reduction. If there were alternative diuretics, why prescribe HCTZ? Chlorthalidone is often offered as an alternative to HCTZ, but has limited pharmaceutical formulations. However, there are seven evidence-based, single-tablet, alternative diuretics. For reducing CVE, the following are superior to their comparators: chlorthalidone versus four antihypertensives in multiple hypertensive populations; indapamide versus placebo in elderly Chinese (and versus enalapril for left ventricular hypertrophy), triamterene-HCTZ versus placebo in elderly Europeans, amiloride-HCTZ versus three antihypertensives, and indapamide-perindopril versus placebo in three populations. Additionally, chlorthalidone-azilsartan and spironolactone-HCTZ are potent combinations The aldosterone antagonist component of the latter combination has been shown to reduce total mortality by 30 % in heart failure. Five of these seven have multiple dose formulations. Six cost $4-$77 monthly. In conclusion, based on both scientific and practical grounds, new prescriptions for HCTZ are rarely justified.

Head-to-head comparisons of hydrochlorothiazide with indapamide and chlorthalidone: antihypertensive and metabolic effects

Hydrochlorothiazide (HCTZ) has often been contrasted with chlorthalidone, but relatively little is known about HCTZ versus indapamide (INDAP). This systematic review retrieved 9765 publications, and from these, it identified 14 randomized trials with 883 patients comparing HCTZ with INDAP and chlorthalidone on antihypertensive potency or metabolic effects. To make fair comparisons, the dose of the diuretic in each arm was assigned 1 of 3 dose levels. In random effects meta-analysis, INDAP and chlorthalidone lowered systolic blood pressure more than HCTZ: -5.1 mm Hg (95% confidence interval, -8.7 to -1.6); P=0.004 and -3.6 mm Hg (95% confidence interval, -7.3 to 0.0); P=0.052, respectively. For both comparisons, there was minimal heterogeneity in effect across trials and no evidence for publication bias. The HCTZ-INDAP contrast was biased in favor of greater HCTZ potency because of a much greater contribution to the overall effect from trials in which the HCTZ arm had a higher dose level than the INDAP arm. For the HCTZ-INDAP comparison, no single trial was responsible for the overall result nor was it possible to detect significant modifications of this comparison by duration of follow-up, high- versus low-bias trials, or the presence or absence of background medications. There were no detectable differences between HCTZ and INDAP in metabolic adverse effects, including effects on serum potassium. In conclusion, these head-to-head comparisons demonstrate that, like chlorthalidone, INDAP is more potent than HCTZ at commonly prescribed doses without evidence for greater adverse metabolic effects.

Phase quantification of antihypertensive drugs - Chlorthalidone, Hydrochlorothiazide, Losartan and combinations, Losartan/Chlorthalidone and Losartan/Hydrochlorothiazide - by the Rietveld method

The identification and quantification of crystalline phases of antihypertensive drugs - Losartan potassium (LOS-K), Hydrochlorothiazide (HCTZ) and Chlorthalidone (CTD) were carried out by means of X-ray powder diffraction data and the Rietveld method. Quantitative phase analyses of Losartan potassium/Chlorthalidone (LOS-K/CTD) and Losartan potassium/Hydrochlorothiazide (LOS-K/HCTZ) combinations were also evaluated. The results indicated that for diuretics (HCTZ and CTD) only one crystalline phase was found in samples, and for LOS-K the crystal structure showed similarity between the Bragg peaks to the phase described as monoclinic and space group P21/c. After one year storage, the orthorhombic one was also observed in this sample.

Clinical experience in treating hypertension with fixed-dose combination therapy: angiotensin II receptor blocker losartan plus hydrochlorothiazide

The goal of antihypertensive treatment is to reduce cardiovascular and cerebrovascular events associated with high blood pressure. A combination therapy with different antihypertensive agents is more successful than monotherapy in most hypertensive patients, with the added advantage of a better safety profile. Therefore, treatment of hypertensive patients with fixed-dose combination therapy consisting of the angiotensin II receptor blocker losartan along with hydrochlorothiazide (HCTZ) has several potential benefits over monotherapy with each individual component. It provides more effective blood pressure control, a reduction in the likelihood of adverse effects and facilitation of patient compliance due to a simple once-daily regimen. One of the advantages of the combination of losartan with HCTZ is the potential reduction in HCTZ-induced metabolic disorders; in particular, this combination can have attractive benefits for patients of hyperuricemia. Losartan plus HCTZ fixed-dose combination therapy is frequently recommended for the treatment of hypertension and lowers blood pressure in mild-to-moderate and even severe hypertensive patients to a level comparable with other classes of antihypertensive agents in combination with HCTZ. Fixed-dose combination therapy with losartan plus HCTZ is a logical choice as antihypertensive therapy for patients in whom combination therapy is necessary to achieve additional blood pressure reduction.

Chlorthalidone - a renaissance in use?

Diuretic therapy remains a mainstay of hypertension treatment, either given as monotherapy or used in combination with other antihypertensive compounds. Several issues have complicated the issue of diuretic use with that of class effect being the one that has proven most difficult. Hydrochlorothiazide is a commonly used thiazide diuretic; whereas chlorthalidone is a structurally similar compound, quite dissimilar pharmacokinetically with a much longer half-life for effect and a wider volume of distribution with heavy partitioning in red blood cells. These pharmacokinetic features afford chlorthalidone a unique advantage in its capacity to act as an effective diuretic and blood-pressure-lowering agent, as well as a compound that improves cardiovascular outcomes in the patient with hypertension. Chlorthalidone has been used sparingly in clinical practice in large measure because it is not readily available in many fixed-dose combination products. Fixed-dose combinations containing chlorthalidone and an angiotensin-receptor blocker are now in development. It remains to be determined how well these two therapies will reduce blood pressure in the general population while keeping compound-specific side effects to a minimum.