Antihypertensive Efficacy of Angiotensin Receptor Blockers as Monotherapy as Evaluated by Ambulatory Blood Pressure Monitoring: A Meta-Analysis
What is the incremental antihypertensive efficacy with uptitration of angiotensin-receptor blocker (ARB) dosage and the antihypertensive efficacy of losartan compared with other ARBs?
The investigators systematically reviewed PubMed/EMBASE/Cochrane databases for all randomized clinical trials until December 2012, reporting 24-hour ambulatory blood pressure (ABP) for most commonly available ARBs in patients with hypertension. Reduction in ABP with ARBs was evaluated at 25% of the maximum (max) dose, 50% of the max dose, and at the max dose. Comparison was made between 24-hour BP-lowering effect of losartan 50 and 100 mg and other ARBs at 50% max dose and the max dose, respectively. Sixty-two studies enrolling 15,289 patients (mean age, 56 years; 60% men) with a mean duration of 10 weeks were included in the analysis.
Overall, the dose–response curve with ARBs was shallow with a decrease of 10.3/6.7 (systolic/diastolic), 11.7/7.6, and 13.0/8.3 mm Hg with 25% max dose, 50% max dose, and with the max dose of ARBs, respectively. Losartan in the dose of 50 mg lowered ABP less well than other ARBs at 50% max dose by 2.5 mm Hg systolic (p < 0.0001) and 1.8 mm Hg diastolic (p = 0.0003). Losartan 100 mg lowered ABP less well than other ARBs at max dose by 3.9 mm Hg systolic (p = 0.0002) and 2.2 mm Hg diastolic (p = 0.002).
The authors concluded that there is a shallow dose–response curve with ARBs, and uptitration marginally enhanced their antihypertensive efficacy.
This study reported that ARBs may have a shallow dose–response curve. Doubling the dose merely increased the antihypertensive efficacy by <2 mm Hg systolic or diastolic. Among ARBs, losartan had a similarly shallow dose–response curve and, in head-to-head comparisons with other ARBs, was significantly less efficacious at all doses compared to other ARBs. Overall these data, together with other previously published data, suggest that uptitration of monotherapy has little benefits, and antihypertensive combination therapy may be considered over uptitration of a single agent for better hypertension management.
Keywords: Angiotensin Receptor Antagonists, Blood Pressure Monitoring, Ambulatory, Hypertension
< Back to Listings