Comparison of combination therapies, including the angiotensin receptor blocker olmesartan and either a calcium channel blocker or a thiazide diuretic, in elderly patients with hypertension

Thiazide Diuretics and Fracture Risk: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Thiazide diuretics are commonly used antihypertensive agents. Until today, whether their use reduces fracture risk remains unclear. Our objective was to conduct a systematic review of thiazide diuretics' effects on fractures and bone mineral density (BMD) in randomized clinical trials (RCT) of adults. MEDLINE, EMBASE, CENTRAL, and the WHO's ICTRP registry were searched from inception to July 31, 2019. Two reviewers assessed studies for eligibility criteria: (i) RCTs; (ii) including adults; (iii) comparing thiazides, alone or in combination; (iv) to placebo or another medication; and (v) reporting fractures or BMD. Conference abstracts and studies comparing thiazides to antiresorptive or anabolic bone therapy were excluded. Bias was assessed using Cochrane Collaboration's Risk of Bias Tool-2. The primary outcome was fracture at any anatomical site. Secondary outcomes were osteoporotic fractures, hip fractures, and BMD at femoral neck, lumbar spine, and/or total hip. Fractures were pooled as risk ratios (RRs) using random-effect models. Prespecified subgroup analyses and post hoc sensitivity analyses were conducted. From 15,712 unique records screened, 32 trials (68,273 patients) met eligibility criteria. Thiazides were associated with decreased fractures at any site (RR = 0.87, 95% confidence interval [CI] 0.77-0.98; I 2  = 0%) and osteoporotic fractures (RR = 0.80; 95% CI 0.69-0.94; I 2  = 0%). Results were consistent in most subgroups and sensitivity analyses. Few studies reported hip fractures, and no association was found between thiazides and this outcome (RR = 0.84; 95% CI 0.67-1.04; I 2  = 0%). Only four studies reported BMD; a meta-analysis was not conducted because BMD reporting was inconsistent. Trials were deemed at low (3 studies, weight = 3%), some concerns (16 studies; 71%), or high (11 studies; 26%) risk of bias for the primary outcome. In conclusion, thiazide diuretics decreases the risk of fractures at any and at osteoporotic sites in a meta-analysis of RCTs. Additional studies are warranted in patients with high fracture risk. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Thiazide Diuretic-Induced Change in Fasting Plasma Glucose: a Meta-analysis of Randomized Clinical Trials

BACKGROUND

Prior meta-analyses measuring thiazide-induced glycemic change have demonstrated an increased risk of incident diabetes; however, this measure's definition has changed over time.

AIM

To determine the magnitude of change in fasting plasma glucose (FPG) for thiazide diuretics.

DATA SOURCES

A research librarian designed and conducted searches in Medline®, EMBASE, and EBM Reviews-Cochrane Central Register of Controlled Trials (inception through July 2018) and International Pharmaceutical Abstracts (inception to December 2014).

STUDY SELECTION

Randomized, controlled trials comparing a thiazide or thiazide-like diuretic to any comparator reporting FPG were identified. Trials enrolling < 50 participants, those with a follow-up period of < 4 weeks, and conference abstracts were excluded.

DATA EXTRACTION

Independent duplicate screening of citations and full-text articles, data extraction, and assessment of risk of bias was conducted.

DATA SYNTHESIS

Ninety-five studies were included (N = 76,608 participants), with thiazides compared with placebo, beta-blockers, calcium channel blockers, renin-angiotensin-aldosterone-system inhibitors, potassium-sparing diuretic, and others alone or in combination. Thiazide diuretics marginally increased FPG (weighted mean difference 0.20 mmol/L (95% CI 0.15-0.25); I2 = 84%) (1 mmol/L = 18 mg/dL). Results did not change substantially when considering dose or duration, comparing thiazides with placebo or an active comparator, or using thiazides as monotherapy or combination therapy, even when combined with a potassium-correcting agent.

CONCLUSION

Thiazide diuretics have a small and clinically unimportant impact on FPG.

Renoprotective effects of renin-angiotensin system inhibitor combined with calcium channel blocker or diuretic in hypertensive patients: A PRISMA-compliant meta-analysis

OBJECTIVES

To conduct a meta-analysis of studies comparing the renoprotective effects of angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEI/ARB) combined with either calcium channel blocker (CCB) or diuretic, but not both, in hypertensive patients.

DATA SOURCES

Pubmed, Embase, Medline, and Cochrane databases were searched to identify randomized controlled trials (RCTs) of blood pressure lowering treatments in patients with hypertension.

STUDY SELECTION

RCTs comparing the renoprotective effects of ACEI/ARB plus CCB with ACEI/ARB plus diuretic in hypertensive patients, with at least one of the following reported outcomes: urinary protein, estimated glomerular filtration rate/creatinine clearance (eGFR/CrCl), or serum creatinine.

RESULTS

Based on 14 RCTs with 18,125 patients, statistically significant benefits were found in ACEI/ARB plus CCB for maintaining eGFR/CrCl (standardized mean difference [SMD] = 0.36; 95% confidence interval [CI]: 0.20-0.53; P < 0.001), serum creatinine reduction (mean difference [MD] = -0.05 mg/dL; 95% CI: -0.07 to -0.03; P < 0.001). However, no statistical differences were found between the 2 therapeutic strategies in terms of urinary protein (MD = 7.48%; 95% CI: -6.13% to 21.08%; P = 0.28; I = 92%).

CONCLUSIONS

This meta-analysis concluded that ACEI/ARB plus CCB have a stronger effect on the maintenance of renal function in patients with hypertension than ACEI/ARB plus diuretic.

Comparison of telmisartan/amlodipine and telmisartan/hydrochlorothiazide in the treatment of Japanese patients with uncontrolled hypertension: the TAT-Kobe study

OBJECTIVE

The aim of this study was to compare the efficacy and safety of telmisartan plus amlodipine with telmisartan plus hydrochlorothiazide for the treatment of uncontrolled hypertension.

METHODS

Japanese hypertensive patients with uncontrolled hypertension, despite taking angiotensin II receptor blockers, were assigned randomly to either a fixed-dose combination of telmisartan/amlodipine (n=36) or telmisartan/hydrochlorothiazide (n=39). The primary endpoint was the change in office blood pressure from the baseline value at 12 weeks.

RESULTS

Both telmisartan/amlodipine and telmisaratan/hydrochlorothiazide reduced the office blood pressure efficiently (systole: -25.5±12.1 vs. -24.3±15.0 mmHg, P=0.705; diastole: -10.8±13.8 vs. -11.4±12.3 mmHg, P=0.832). Treatment with telmisartan/hydrochlorothiazide resulted in the quicker onset of blood pressure-lowering effects compared with telmisartan/amlodipine. The target therapeutic blood pressure was similar in both groups at the 12-week visit. Home blood pressure measurements taken in the mornings and evenings were also similar in both groups. Compared with the telmisartan/amlodipine group, serum potassium and brain natriuretic peptide levels decreased and uric acid and hemoglobin A1c levels increased significantly in the telmisartan/hydrochlorothiazide group. Both treatment groups showed a significant reduction in urine albumin. However, the estimated glomerular filtration rate decreased slightly but significantly in the telmisartan/hydrochlorothiazide group alone. Severe adverse effects were not observed in both groups.

CONCLUSION

Combination therapy with telmisartan/amlodipine or telmisartan/hydrochlorothiazide led to efficient blood pressure reduction among Japanese patients with previously uncontrolled hypertension with angiotensin II receptor blocker monotherapy.

Antihypertensive and metabolic effects of hydrochlorothiazide versus amlodipine when added to losartan in patients with type 2 diabetes

We performed a prospective, randomized, multicenter, parallel-group, per-protocol study to compare the effects of hydrochlorothiazide (HCTZ) and amlodipine as add-on to losartan treatment in hypertensive type 2 diabetic patients. A total of 49 Japanese type 2 diabetic patients with inadequate control of blood pressure while receiving losartan 50 mg were randomly allocated to receive a fixed-dose single-pill combination of HCTZ 12.5 mg plus losartan (N = 26) or a free combination of amlodipine 5 mg plus losartan (N = 23). During 8 weeks of follow-up, changes in blood pressure and laboratory data including HbA1c, uric acid, and potassium were compared between the groups using analysis of covariance. Systolic and diastolic blood pressure decreased in both groups, the reductions of which were greater in the amlodipine group. However, the least square mean (95 % CI) differences between groups were not statistically significant [2.3 (-6.8 to 11.4) mmHg, p = 0.618 and 2.7 (-2.4-7.9) mmHg, p = 0.293, respectively]. HbA1c increased in patients receiving HCTZ but not in the amlodipine group. Uric acid also increased in patients receiving HCTZ but decreased in patients receiving amlodipine, yielding a significant between-group difference of 1.0 (0.5-1.5) mg/dl (p < 0.001). No intra- or intergroup change was observed in serum potassium levels. This pilot study suggests that HCTZ and amlodipine result in nonsignificant effects on systolic and diastolic blood pressure reduction when administrated as add-on therapy to losartan in hypertensive patients with type 2 diabetes; however, addition of HCTZ may be associated with less favorable effects on metabolic profiles than amlodipine.

Olmesartan in the treatment of hypertension in elderly patients: a review of the primary evidence

Hypertension, particularly systolic hypertension, is prevalent in the elderly and increases with advancing age, in part because of age-related endothelial dysfunction and increased arterial stiffness. There is strong evidence from randomized clinical trials that supports the use of antihypertensive treatment for effective and sustained blood pressure (BP) control in older patients to reduce the risk of vascular-related morbidity and mortality, particularly cerebrovascular accidents, including stroke. Furthermore, current evidence and guidelines suggest that all major classes of antihypertensive agents are equally effective in controlling BP and preventing cardiovascular events in older patients. Diuretics are commonly used in elderly patients, but recent outcomes data have raised doubt about their long-term benefits. Renin-angiotensin system inhibitors have a better tolerability profile than diuretics. Extensive clinical evidence has demonstrated the excellent efficacy and tolerability profile of olmesartan medoxomil (OM)--an angiotensin II receptor blocker AT1 receptor antagonist--including in elderly patients. Randomized and observational studies have shown that OM provides effective BP control across the 24 h dosing interval in the elderly. It also has a good tolerability profile, a pharmacokinetic profile unaffected by age and a low propensity for drug interactions. An additional factor is that OM once-daily regimens are simple and straightforward, which can be an important factor in maintaining adherence to therapy in elderly patients. This article provides an overview of the main recent clinical evidence supporting the use of OM-based therapy in elderly patients with hypertension.

Angiotensin receptor blocker (ARB)-diuretic versus ARB-calcium channel blocker combination therapy for hypertension uncontrolled by ARB monotherapy

Diuretics or calcium channel blockers (CCBs) are used concomitantly with an angiotensin II receptor blocker (ARB). However, it is not established which ARB-based combination therapy is the most effective and safe. This prospective randomized open-label study compared the efficacy and safety of a fixed-dose tablet of losartan (LST)-hydrochlorothiazide (HCTZ) (n = 99) and LST-amlodipine (AML) (n = 77) in Japanese patients whose hypertension was uncontrolled by ARB monotherapy. Blood pressure changed similarly over the 12-month study period. Only LST-HCTZ significantly increased serum uric acid (SUA) in patients with low baseline SUA (<5.6 mg/dL) but not in patients with high baseline SUA.

Efficacy and effects on lipid metabolism of combination treatment with losartan + hydrochlorothiazide versus losartan + amlodipine: a 48-week prospective, multicenter, randomized, open-label trial

BACKGROUND

Both combination therapies of an angiotensin II receptor blocker (ARB) with the thiazide diuretic hydrochlorothiazide (HCTZ) and an ARB with a calcium channel blocker (CCB) are recommended to achieve blood pressure (BP) goals in antihypertensive treatment. However, although HCTZ is known to have unfavorable effects on lipid metabolism, the effects of HCTZ in the ARB + HCTZ combination on lipid metabolism have not been fully elucidated.

OBJECTIVE

The aim of this study was to compare the effects on lipid metabolism of combination treatment with the ARB losartan + HCTZ and losartan + the CCB amlodipine and to assess the efficacy in BP lowering of these 2 combination therapies. The metabolism of glucose, uric acid (UA), and high-sensitivity C-reactive protein (hs-CRP), an inflammation marker of atherosclerosis, were also assessed in association with lipid metabolism.

METHODS

This 48-week, prospective, randomized, open-label trial was conducted at 2 clinics and 2 hospitals in Tokorozawa City (Saitama, Japan) and Shinjuku-ku Ward (Tokyo, Japan). Eligible patients had a systolic BP (SBP) >140 mm Hg and/or diastolic BP (DBP) >90 mm Hg despite a >1-month history of monotherapy with an ARB. Patients were randomly assigned to receive losartan 50 mg/d + HCTZ 12.5 mg/d (LOS + HCTZ) or losartan 50 mg/d + amlodipine 5 mg/d (LOS + CCB) for 48 weeks. Follow-up visits were scheduled at 4, 8, 12, 24, and 48 weeks. Biochemical measurements were centrally measured at a single institute. Tolerability and treatment compliance were assessed by physicians every 4 weeks.

RESULTS

A total of 112 patients were enrolled; 26 were excluded from the final analysis, leaving 42 and 44 patients in the LOS + HCTZ and LOS + CCB groups, respectively, included in the final analysis. At 48 weeks, SBP and DBP were significantly decreased in the 2 treatment groups (both, P < 0.0001). The decrease in SBP was significantly greater in the LOS + HCTZ group than in the LOS + CCB group (P < 0.001). The difference in the decrease in DBP between the 2 groups was nonsignificant. There were no significant differences in the changes from baseline (Δ) in any of the lipid parameters between the 2 groups. The decreases at 8 and 12 weeks in LDL-C, TC, and apolipoprotein (apo) B were significantly greater in the LOS + CCB group compared with those in the LOS + HCTZ group. The between-group differences in ΔTG, ΔHDL-C, ΔapoA-1, and ΔapoE throughout the study were nonsignificant. Changes in fasting plasma glucose (FPG), hemoglobin A1c, and hs-CRP were not significantly different between the 2 groups. The between-group difference in ΔUA in men was not significant, but a significant difference was found in women (LOS + HCTZ, 0.74 mg/dL; LOS + CCB, 0.28 mg/dL [P = 0.0017]). No clinically significant adverse events were reported with either treatment throughout the study.

CONCLUSIONS

The findings from the present study suggest that LOS + HCTZ was more efficacious in decreasing SBP than was LOS + CCB in the management of hypertension refractory to ARB monotherapy. Unfavorable effects on lipid metabolism were not observed with either combination therapy.

Differential blood pressure reductions by angiotensin receptor blocker plus calcium channel blocker or diuretic in elderly hypertension with or without obesity

We conducted the Miyazaki Olmesartan Therapy for Hypertension in the EldeRly (MOTHER) study, which suggested that there are preferable effects of an angiotensin receptor blocker (ARB), olmesartan, plus a calcium channel blocker (CCB) over the ARB plus a diuretic, in elderly patients with hypertension. In this subanalysis, we examined whether obesity influences the efficacies of these combination therapies. The study subjects were 58 hypertensive patients ages 65 to 85, who had been randomly assigned to either group treated with olmesartan plus a CCB or a diuretic and completed the treatment for 6 months. Systolic and diastolic blood pressures were reduced following these combination treatments in nonobese and obese patients. In the CCB combination, blood pressure reductions in nonobese patients were larger than in obese patients at 1 and 3 months, and serum creatinine remained unchanged despite the greater reduction of blood pressure. Meanwhile, such differences were not noted in the diuretic groups. Plasma aldosterone was significantly reduced in nonobese patients of two combination groups, but not in those with obesity. ARB plus CCB combination therapy might be preferably chosen for nonobese elderly patients, whereas the influence of obesity seems smaller in the efficacy of ARB plus a diuretic.

Hydrochlorothiazide versus calcium channel blockers: what is the best add-on to a renin-angiotensin system blocker for treating hypertension in patients with renal disease?

Hypertension remains an important problem that increases the risk of cardiovascular disease and is a leading cause of mortality worldwide. Achieving long-term control of arterial hypertension, which has an estimated prevalence of 28% in the US adult population, would translate into a significant reduction in cardiovascular events. Specific causes can be identified and treated for certain forms of secondary hypertension, but often it is multifactorial. Therefore, it makes sense to attain blood pressure control by addressing more than one pressor mechanism. Several clinical studies have demonstrated that combination antihypertensive therapy is more effective than monotherapy, and a review of currently published data suggests that approximately 75% of hypertensive individuals will require some form of combination therapy to achieve target blood pressure (BP) goals. To this end, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of Blood Pressure (JNC 7) has recommended that antihypertensive therapy should start with two drugs when a patient presents with systolic blood pressure (SBP) more than 20 mm Hg above target levels, diastolic blood pressure (DBP) more than 10 mm Hg above target levels, or both. This review attempts to analyze the current evidence in published medical literature to answer the question of whether hydrochlorothiazide or a calcium channel blocker is a better add-on to a renin-angiotensin system blocker for treating hypertension in patients with renal disease.