Intensive glycemic control and macrovascular events in type 2 diabetes mellitus: a meta-analysis of randomized controlled trials

Background There is no agreement as to whether intensive glucose control in type 2 diabetes can reduce the incidence of macrovascular events in these patients. We performed a meta-analysis comparing intensive glucose control or conventional glucose control in randomized controlled trials. Methods Databases including MEDLINE, EMBASE, and Cochrane controlled trials register, the Cochrane Library, and Science Citation Index were searched to find relevant trials. Outcome measures were the incidence of major macrovascular events. Results Six trials involving 28 065 patients were included. Analysis suggested that there was an obviously decreased incidence of major macrovascular events in patients having intensive glucose treatment vs. controls (RR 0.92; 95% CI 0.87, 0.98; P=0.005). However, intensive glycemia control strategies in type 2 diabetes showed no significant impact on the incidence of death from any cause compared with conventional glycemia control strategies, intensive 14.7%, controls 12.0% (RR 0.95; 95% CI 0.80, 1.12; P=0.55), as well as on the incidence of cardiovascular death, intensive 3.7%, controls 3.6% (RR 1.10, 95% CL 0.79, 1.53; P=0.57). Conclusions Control of glycemia to normal (or near normal levels) in type 2 diabetes appears to be effective in reducing the incidence of major macrovascular events, but there were no significant differences of either the mortality from any cause or from cardiovascular death between the two glycemia-control strategies. Chin Med J 2010;123(20):2908-2913