Efficacy of Statin Therapy in Pulmonary Arterial Hypertension: A Systematic Review and Meta-Analysis

Since the evidence regarding statin therapy in PAH has not been conclusive, we assessed the impact of statin therapy in PAH through a systematic review and meta-analysis of available studies. We searched selected databases up to August 1, 2015 to identify the studies investigating the effect of statin administration on PAH. Meta-analysis was performed using either a fixed-effects or random-effect model according to I 2 statistic. Meta-analysis of 8 studies with 665 patients did not suggest any significant improvement in 6-min walking distance (6MWD) by statin therapy (weighed mean difference [WMD]: −6.08 m, 95% confidence interval [CI]: −25.66, 13.50, p  = 0.543; Q = 8.41, I 2  = 28.64%). Likewise, none of the other indices including pulmonary arterial pressure (WMD: −0.97 mmHg, 95%CI: −4.39, 2.44, p  = 0.577; Q = 14.64, I 2  = 79.51%), right atrial pressure (WMD: 1.01 mmHg, 95%CI: −0.93, 2.96, p  = 0.307; Q = 44.88, I 2  = 95.54%), cardiac index (WMD: 0.05 L/min/m 2 , 95%CI: −0.05, 0.15, p  = 0.323; Q = 3.82, I 2  = 21.42%), and pulmonary vascular resistance (WMD: −1.42 dyn*s/cm 5 , 95%CI: −72.11, 69.27, p  = 0.969; Q = 0.69, I 2  = 0%) was significantly altered by statin therapy. In conclusion, the results of the meta-analysis did not show a statistically significant effect of statin therapy in the improvement of 6MWD, pulmonary arterial pressure, right atrial pressure, cardiac index and pulmonary vascular resistance.