NEW ORLEANS--While calcium channel blockers (CCB) have been previously recommended as a first-line treatment strategy for diabetic, hypertension patients, currently, ACE inhibitors and ARBs have been shown to be more efficacious. Results of the NAGOYA HEART study, presented as a late-breaking clinical trial April 5, showed that while valsartan reduced the risk of congestive heart failure compared with amlodipine-based treatment, results were similar for the two treatments in terms of cardiovascular outcomes.
Because few trials have compared the use of ARBs to CCBs in hypertensive, diabetic patients, Toyoaki Murohara, MD, PhD, of the Nagoya University Graduate School of Medicine in Nagoya, Japan, and colleagues compared the safety and efficacy of the ARB valsartan (Diovan, Novartis) to the CCB amlodipine (Norvasc, Pfizer) using a composite of CV events as the primary endpoint.
The prospective, randomized open-label trial enrolled 1,150 hypertension and diabetic or impaired glucose tolerance (IGT) patients at a 1:1 ratio to receive either a daily dose of valsartan (575 patients) or amlodipine (575 patients). Eighty-two percent of the patients enrolled were type 2 diabetic.
“After a follow-up of a median of 3.2 years, blood pressure and glucose controls adjusted by A1c1 levels were comparable between the two groups,” said Murohara who presented the results of the NAGOYA HEART study April 5 at the annual American College of Cardiology scientific sessions. “Blood pressure was 171/73 mm/Hg in the valsartan arm and 132/74 mm/Hg in the amlodipine arm.”
In terms of CV events, Murohara reported no significant differences between the two groups, 9.4 percent in the valsartan arm and 9.7 percent in the amlodipine arm. The rates of acute MI were 1.2 percent vs. 0.5 percent for valsartan and amlodipine.
“During the trial, superiority of the ARB for the prevention of HF was confirmed,” Murohara noted.
However, Murohara did note that limitations of the study stemmed from the fact that “there was a lower incidence of primary composite cardiovascular events as well as smaller sample size than anticipated.” Additionally, due to the fact that Japan is a country with very low rates of major CV disease, theresults may not be generalizable to other populations.
In conclusion, “The NAGOYA HEART study showed no difference between the valsartan- or amlodipine-based antihypertensive treatments in terms of preventing composite cardiovascular outcomes, however, the valsartan-based treatment significantly reduced heart failure compared to the amlodipine-based treatment.
“Our results highlight the safety and efficacy of the ARB valsartan especially in preventing HF in diabetic hypertensive patients.”