TUESDAY, April 5 (HealthDay News) -- An angiotensin II receptor blocker (ARB) appears to provide similar effects on cardiovascular outcomes as a calcium channel blocker (CCB) in patients with hypertension and glucose intolerance, while a combination of an ARB and a CCB seems to benefit elderly patients with hypertension and cardiovascular disease compared to a high-dose ARB alone, according to research presented at the American College of Cardiology's 60th Annual Scientific Session & Expo, held from April 2 to 5 in New Orleans.
Toyoaki Murohara, M.D., Ph.D., of Nagoya University in Japan, and colleagues randomized 1,150 patients with hypertension and either type 2 diabetes or impaired glucose tolerance to receive either an ARB (valsartan) or a CCB (amlodipine) as their first-line treatment. The primary outcome measure was a composite of acute heart attack, stroke, coronary revascularization, hospital admission due to congestive heart failure, and sudden cardiac death. The investigators found that the primary outcome occurred in 54 patients (9.4 percent) in the valsartan group and 56 patients (9.7 percent) in the amlodipine group, an insignificant difference. There were no significant differences in all-cause mortality or adverse events.
Hisao Ogawa, M.D., Ph.D., of Kumamoto University in Japan, and colleagues randomized 1,164 high-risk elderly hypertension patients to receive high-dose olmesartan or a CCB combined with olmesartan. The primary end point was a composite of cardiovascular events and all-cause death. Blood pressure was adequately controlled in both treatment groups; however, the combination therapy reduced blood pressure to significantly lower levels than monotherapy. The investigators found no significant difference between the two groups in the number of primary end points. However, among patients with pre-existing cardiovascular disease, those in the combination therapy group had significantly fewer occurrences of cardiovascular events and death compared with those in the monotherapy group.
"The OSCAR study provides the first evidence showing that a standard dose of ARB plus CCB combination is superior to high-dose ARB treatment in reducing adverse events in elderly hypertensive patients with cardiovascular disease," Ogawa said in a statement. "However, high-dose ARB better prevented adverse events in diabetic patients in spite of its weaker antihypertensive effect."
Nagoya University has received grants from pharmaceutical companies, including Novartis and Pfizer, the manufacturers of valsartan (Diovan) and amlodipine (Norvasc), respectively. Ogawa has received funding from pharmaceutical companies, including Daiichi Sankyo, the manufacturer of olmesartan (Benicar).
Press Release - Murohara
Press Release - Ogawa