NAGOYA HEART: ARB, calcium antagonist equally effective in patients with diabetes, hypertension

American College of Cardiology 60th Annual Scientific Sessions

NEW ORLEANS — Valsartan, an angiotensin II receptor blocker, and amlodipine, a calcium antagonist, comparably reduced adverse CV events in hypertensive patients with diabetes or glucose intolerance, according to data presented here.

“Many hypertension treatment guidelines recommend angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs) as first-line treatment for hypertensive patients with diabetes, especially for prevention of major CV events,” Toyoaki Murohara, MD, PhD, lead researcher of the NAGOYA HEART Study, said during a press conference. “But some clinical trials show that calcium antagonists are almost equally effective in reducing the risk of CV disease as compared to ARBs.”

The NAGOYA HEART Study is the first randomized trial comparing the efficacy of an ARB with a calcium antagonist, according to Murohara. For the trial, Murohara and colleagues recruited 1,150 hypertensive patients with diabetes or glucose intolerance at 46 facilities in Japan. Between October 2004 and July 2010, the researchers randomly assigned patients to receive valsartan (Diovan, Novartis) or amlodipine (Norvasc, Pfizer) as first-line treatment. The study’s primary outcome measure was a composite of CV events, including acute myocardial infarction, stroke, coronary revascularization, hospital admission resulting from congestive heart failure (CHF) and sudden cardiac death. Blood pressure and HbA1c levels were also monitored.

Follow-up lasted a median of 3.2 years, with analysis occurring every month for the first 3 months and then every 1 to 3 months thereafter. Results revealed that 54 patients (9.4%) assigned to valsartan and 56 (9.7%) assigned to amlodipine experienced the primary outcome (HR=0.97; 95% CI, 0.66-1.4), suggesting no significant differences between treatment groups. Analysis of individual components of the primary outcome, however, indicated that the incidence of hospital admission for CHF was higher in the amlodipine group, with the event occurring in three patients (0.5%) in the valsartan arm vs. 15 patients (2.6%) in the amlodipine arm (HR=0.2; 95% CI, 0.06-0.69).

BP and HbA1c levels also appeared similar between the groups, the researchers said. At 54 months, BP decreased to 131/73 mm Hg in the valsartan group and 132/74 mm Hg in the amlodipine group. HbA1c levels were lowered to 6.7% in both groups.

“Our present paper shows that ARB is superior to a calcium antagonist in HF, and clinical trends already show ACE inhibitors slow [the development of] some of the complications of diabetes,” Murohara said. “Our study results support the current guidelines recommending ARB and ACE inhibitors for first-line treatment in diabetic patients with hypertension.”

For more information:

Murohara T. LBCT IV, 3015. Presented at: ACC 60^th Annual Scientific Sessions; April 2-5, 2011; New Orleans.

Disclosure: Dr. Murohara receives lecturer’s fees from Daiichi-Sankyo, Novartis, Pfizer and Takeda (Modest). In the past 5 years, he has also received research grants from Astellas, AstraZeneca, Bayer, Boehringer Ingelheim, Daiichi Sankyo, Eisai, Kowa, Kyowa Hakko Kirin, MSD, Novartis, Pfizer, Sanofi Aventis, Schering-Plough and Takeda.

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