Effect of angiotensin receptor blockers in the prevention of type 2 diabetes and cardiovascular events： a meta-analysis of randomized trials

Background As the incidence of type 2 diabetes is rapidly increasing, prevention of the disease should be considered as a crucial objective in the near future. Several studies have shown angiotensin receptor blockers （ARBs） may contribute to the prevention of new-onset type 2 diabetes. This study was conducted to determine if ARBs as monotherapy or combination therapy may experience a decreased incidence of new-onset type 2 diabetes and prevent cardiovascular events. Methods Relevant experimental and clinical studies were identified by searching MEDLINE （1969 to May 30, 2011） to extract a consensus of trial data involving the effect of ARBs on prevention of new-onset type 2 diabetes and cardiovascular events. Studies were included if they were randomized controlled trials versus placebo/routine therapy. A random-effects model was utilized. Subgroup and sensitivity analyses were conducted. Results Eleven trials were identified, including 82738 patients. ARBs prevented new-onset type 2 diabetes （odds ratio 0.8 （95% CI 0.76, 0.85））. Regardless of indication for use, essential hypertension （seven trials）, impaired glucose tolerance （one trial）, cardiocerebrovascular disease （two trials） or heart failure （one trial）, reductions in new-onset type 2 diabetes were maintained （0.75 （0.69, 0.82）, 0.85 （0.78, 0.92）, 0.80 （0.76, 0.85） and 0.80 （0.64, 0.99）, respectively）. No statistical heterogeneity was observed for any evaluation. However, ARBs did not significantly reduce the odds of all-cause mortality, myocardial infarction and heart failure versus control therapy among all of these studies. But ARBs did reduce the odds of cardiac death and heart failure among the heart failure study versus control therapy. Conclusion ARBs have significant ability to reduce risk of developing new-onset type 2 diabetes but does not improve cardiovascular outcomes over the study follow-up periods among all of included studies.