Telmisartan and valsartan associated with fewer hospitalizations for cardiovascular events than other ARBs, study finds

In patients with diabetes, telmisartan and valsartan were associated with lower rates of hospitalization for cardiovascular events than other angiotensin-receptor blockers (ARBs), according to a recent retrospective study.

The population-based cohort study included about 54,000 Ontario residents over age 65 who had type 2 diabetes and started treatment with telmisartan, valsartan, candesartan, irbesartan or losartan between 2001 and 2011. The primary outcome was a composite of hospital admission for acute myocardial infarction, stroke or heart failure. Results were published by CMAJ on July 8.

After multivariable adjustment, patients taking telmisartan or valsartan had a lower risk of the primary outcome than those on irbesartan (adjusted hazard ratio [HR] for telmisartan, 0.85 [95% CI, 0.74 to 0.97]; HR for valsartan, 0.86 [95% CI, 0.77 to 0.95]). There were no significant differences in the primary outcome among the other ARBs. The researchers also found a reduction specifically in hospitalizations for heart failure with telmisartan compared to irbesartan (HR, 0.79 [95% CI, 0.66 to 0.96]).

The observed advantages of telmisartan may be due to its activation of the PPARγ receptor, the study authors speculated. The benefit found for valsartan is harder to explain and was attenuated by adjustment for dose, but it may be related to inhibition of platelet aggregation, they wrote. The study was limited by its observational nature, but many variables were controlled for and a randomized trial of all these agents is unlikely, so the authors concluded telmisartan and valsartan may be the preferred ARBs for older patients with diabetes. The results are not necessarily applicable to younger patients or those without diabetes, they noted.

An accompanying editorial expressed doubts about the authors' conclusions, arguing that PPARγ agonism would not lead to the cardiovascular benefit seen in the study and that there was no likely explanation for the observed advantage of valsartan. The results are intriguing, the editorialist wrote, but “there is scant evidence to support preferring one drug in this class over another for patients with type 2 diabetes.”