Effects of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers on cardiovascular events in patients with diabetes and overt nephropathy: a meta-analysis of randomised controlled trials

Objective: The efficacy of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in reducing cardiovascular outcomes in patients with diabetes and overt nephropathy is still a controversial issue. Methods: We systematically searched MEDLINE, Embase and Cochrane Library for randomised controlled trials. Results: Thirteen trials containing 4638 patients with diabetes and overt nephropathy were included. Compared with controls, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker treatment did not reduce the risk of cardiovascular events (odds ratio 0.94, 95% confidence interval 0.86 to 1.03, P=0.18; I 2 =0.0%, P=0.75). Angiotensin-converting enzyme inhibitor/angiotensin receptor blocker therapy reduced the odds of heart failure events by 29% (0.71, 0.61 to 0.83, P<0.001; I 2 =0%, P=0.78). The results indicated no significant differences between the two treatment regimens with regard to the frequency of MI (0.95, 0.76 to 1.19, P=0.64), stroke (1.20, 0.83 to 1.74, P=0.32), cardiovascular death (1.26, 0.96 to 1.65, P=0.09) and all-cause mortality (0.98, 0.86 to 1.12, P=0.73). Among all kinds of adverse effects, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker therapy increased the incidence of hyperkalemia (2.26, 1.42 to 3.61, P=0.001). Conclusion: This study demonstrated that angiotensin-converting enzyme inhibitors and angiotensin receptor blockers did not reduce cardiovascular events in patients with diabetes and overt nephropathy.