Effect of statin therapy on plasma proprotein convertase subtilisin kexin 9 (PCSK9) concentrations: a systematic review and meta-analysis of clinical trials

Aims: To evaluate the magnitude of the effect of statin therapy on plasma proprotein convertase subtilisin kexin 9 (PCSK9) levels through a systematic review and meta-analysis of clinical trials. Methods: A random-effects model (using DerSimonian-Laird method) and the generic inverse variance method were used for quantitative data synthesis. Heterogeneity was quantitatively assessed using the I-2 index. Sensitivity analyses were conducted using the one-study remove approach. Random-effects meta-regression was performed using an unrestricted maximum likelihood method to evaluate the association between statin-induced elevation of plasma PCSK9 concentrations with duration of treatment and magnitude of LDL cholesterol reduction. Results: A total of 15 clinical trials examining the effects of statin therapy on plasma PCSK9 levels were included. Meta-analysis of data from single-arm statin treatment arms [weighted mean difference (WMD) 40.72 ng/ml, 95% confidence interval (CI) 34.79, 46.65; p< 0.001] and randomized placebo-controlled trials (WMD 22.98 ng/ml, 95% CI 17.95, 28.01; p< 0.001) showed a significant increase in plasma PCSK9 concentrations after statin therapy, irrespective of the type of statin administered in either of the analyses (single-arm or randomized placebo-controlled trial). There was no significant elevation of plasma PCSK9 levels with statin/ezetimibe combination therapy compared with statin monotherapy (WMD 23.14 ng/ml, 95% CI -1.97, 48.25; p = 0.071); however, removal of one study in the meta-analysis yielded a significant result in the sensitivity analysis (WMD 31.41 ng/ml, 95% CI 7.86, 54.97; p = 0.009). Conclusions: This meta-analysis suggests that statin therapy causes a significant increase in plasma PCSK9 concentrations.