Seventy-two RCTs (159,458 patients) were included. Length of follow-up ranged from 0.5 to 6.1 years.
Most studies reported on loss to follow-up (64 trials) and blinding (61 trials), some described random sequence generation (26 trials) and allocation concealment (19 trials). Four trials reported that their primary results were based on a per-protocol analysis (not an intention-to-treat analysis).
There was a statistically significant lower risk of all-cause mortality among those receiving statin therapy versus those receiving a control treatment (RR 0.89, 95% CI 0.86 to 0.93; Ι²=11%; 72 trials).
Compared with control groups, statin groups had statistically significantly higher rates of new incident diabetes (OR 1.09, 95% CI 1.02 to 1.16; Ι²=11%; 16 trials), elevated aspartate aminotransferase levels (OR 1.31, 95% CI 1.04-1.66; Ι²=42%; 22 trials) and elevated alanine aminotransferase levels (OR 1.28, 95% CI 1.11 to 1.48; Ι²=0%; 20 trials).
Atorvastatin was associated with statistically significantly higher levels of aspartate aminotransferase compared with control treatment (OR 2.27, 95% CI 1.19 to 4.30; Ι²=41%; six trials). Compared with control treatments, statistically significantly higher levels of alanine aminotransferase were found for lovastatin (OR 1.54, 95% CI 1.15 to 2.07; Ι² was not applicable; two trials) and simvastatin (OR 1.42, 95% CI 1.03 to 1.96; Ι² was not applicable; two trials). Incidence of diabetes was statistically significantly higher with rosuvastatin versus control treatments (OR 1.14, 95% CI 1.01 to 1.29; Ι²=1.5%, four trials).
Indirect comparisons of the different statins revealed that atorvastatin statistically significantly elevated levels of aspartate aminotransferase compared with pravastatin (OR 2.21, 95% CI 1.13 to 4.29), and simvastatin statistically significantly increased creatinine kinase levels compared with rosuvastatin (OR 4.39, 95% CI 1.01 to 19.07). High dose compared with low dose studies demonstrated a statistically significantly increased risk of aspartate aminotransferase elevations (OR 3.53, 95% CI 2.02 to 6.16, 5 trials).