The effect of statins on severity of psoriasis: A systematic review

Background: Psoriasis is becoming increasingly recognized as a chronic systemic inflammatory disease. Statins are generally well-tolerated drugs with pleiotropic effects including decreasing inflammation and may have the potential to reduce psoriasis severity. Aims: To examine whether oral statins reduce the severity of psoriatic skin disease. Methods: We searched MEDLINE, EMBASE and adapted for Google Scholar, Cochrane Central Register for Controlled Trials and Clinical trials. gov to January 6, 2016. We primarily examined randomized controlled trials that assessed the change in PASI score over a follow-up period of at least 8 weeks, for participants with an established diagnosis of psoriasis taking an oral statin versus placebo or other active treatment. Beyond this, we also examined other interventional studies that investigated the effect of statins on psoriasis severity using other designs. We extracted efficacy and adverse event data. The two study authors examined issues of study quality and study inclusion independently. Results: Three studies were identified which measured the change in psoriasis severity using PASI, comparing statin with placebo or standard therapy alone in a prospective, randomized study design; these showed conflicting results. However, among the excluded studies, majority of which used a single arm, non-placebo controlled study design, most showed an improvement in PASI scores after statin use. Limitations: Included studies were of limited sample size and quality. They were not amenable to pooled analysis. Conclusions: This review highlights the paucity of high quality, randomized, double-blinded, placebo-controlled trials investigating the effects of statins on psoriasis severity using clinically objective measures. There is insufficient evidence that the use of oral statins as an adjunctive therapy can reduce the severity of psoriasis.