Abstract:
Background:
It is unknown whether high-dose angiotensin II receptor blocker therapy or angiotensin II receptor blocker + calcium channel blocker combination therapy is better in elderly hypertensive patients with high cardiovascular risk. The objective of the study was to compare the efficacy of these treatments in elderly,high-risk Japanese hypertensive patients.
Methods:
The OlmeSartan and Calcium Antagonists Randomized (OSCAR) study was a multicenter,prospective,randomized,open-label,blinded-end point study of 1164 hypertensive patients aged 65 to 84 years with type 2 diabetes or cardiovascular disease. Patients with uncontrolled hypertension during treatment with olmesartan 20 mg/d were randomly assigned to receive 40 mg/d olmesartan (high-dose angiotensin II receptor blocker) or a calcium channel blocker + 20 mg/d olmesartan (angiotensin II receptor blocker + calcium channel blocker). The primary end point was a composite of cardiovascular events and noncardiovascular death.
Results:
During a 3-year follow-up,blood pressure was significantly lower in the angiotensin II receptor blocker + calcium channel blocker group than in the high-dose angiotensin II receptor blocker group. Mean blood pressure at 36 months was 135.0/74.3 mm Hg in the high-dose angiotensin II receptor blocker group and 132.6/72.6 mm Hg in the angiotensin II receptor blocker + calcium channel blocker group. More primary end points occurred in the high-dose angiotensin II receptor blocker group than in the angiotensin II receptor blocker + calcium channel blocker group (58 vs 48 events,hazard ratio [HR],1.31,95% confidence interval,0.89-1.92;P=.17). In patients with cardiovascular disease at baseline,more primary events occurred in the high-dose angiotensin II receptor blocker group (HR,1.63,P=.03);in contrast,fewer events were observed in the subgroup without cardiovascular disease (HR,0.52,P=.14). This treatment-by-subgroup interaction was significant (P=.02).
Conclusion:
The angiotensin II receptor blocker and calcium channel blocker combination lowered blood pressure more than the high-dose angiotensin II receptor blocker and reduced the incidence of primary end points more than the high-dose angiotensin II receptor blocker in patients with cardiovascular disease. The addition of a second antihypertensive agent is more effective at lowering blood pressure than simply doubling the dose of an existing agent.
The American Journal of Medicine
