Effect of statins on cardiovascular events in patients with mild to moderate chronic kidney disease: a systematic review and meta-analysis of randomized clinical trials

Background: Statins are commonly used to lower total cholesterol levels in the general population to prevent cardiovascular events. However, the effects of statins in patients with chronic kidney disease remain unclear. We therefore performed a meta-analysis to assess the effects of statin therapy on cardiovascular outcomes in patients with mild to moderate chronic kidney disease. Methods: We systematically searched PubMed, EmBase, the Cochrane Central Register of Controlled Trials, proceedings of major meetings, and reference lists of articles for relevant literature. Only randomized clinical trials were included. Outcomes analysed included cardiovascular disease, total mortality, myocardial infarction, stroke, cardiovascular death, and possible drug-related adverse events. Subgroup analyses were also performed based on the population characteristics and clinical indexes. Results: Twelve trials met our inclusion criteria. Overall, statin therapy resulted in a 24% reduction in the risk of cardiovascular disease (RR = 0.76,95% confidence interval [CI], 0.72- 0.80), a 21% reduction in the risk of total mortality (RR = 0.79,95% CI, 0.72-0.86), a 34% reduction in the risk of myocardial infarction (RR = 0.66,95% CI, 0.52-0.83), a 30% reduction in the risk of stroke (RR = 0.70,95% CI, 0.57-0.85), and a 17% reduction in the risk of cardiovascular mortality (RR = 0.83,95% CI, 0.73- 0.93). No statistically significant drug-related adverse events were noted. Subgroup analysis indicated that some important factors such as baseline creatinine level >= 1.5 mg/dL, baseline glomerular filtration rate (GFR), and cardiovascular disease history could affect cardiovascular outcomes. Conclusion: Statin therapy had a clear effect on cardiovascular disease, total mortality, stroke, and myocardial infarction in patients with mild to moderate renal disease. Subgroup analysis indicated that baseline GFR, baseline creatinine level, and a history of cardiovascular disease might play an important role in the cardiovascular outcomes.