Statin liver safety in non-alcoholic fatty liver disease: a systematic review and metanalysis

Aims: Statin liver safety in non-alcoholic fatty liver disease (NAFLD) patients is not well defined. We analysed differences in liver function tests, including alanine transaminase aminotransferase (ALT), aspartate transaminase (AST) and gamma-glutamyl transpeptidase (GGT) in NAFLD patients treated or not treated with statins. Methods: We performed a systematic review of MEDLINE via PubMed and EMBASE databases and metanalysis of clinical studies investigating levels of ALT, AST and GGT in NAFLD according to statin treatment. Mean difference (MD) and percentage MD were calculated between the two groups. Results: We included 22 studies with 2345 NAFLD patients. Overall, 16 were before-after interventional, five were cross-sectional and one was combined cross-sectional/interventional study. In all interventional studies, except one, patients had raised ALT, AST and GGT at baseline. Interventional studies showed reduced ALT values with an MD reduction of −27.2 U/L (95% CI −35.25/−19.15) and a percentage MD reduction of −35.41% (95% CI −44.78/−26.04). Also, AST values were reduced after statin treatment in interventional studies with an MD of −18.82 U/L (95% CI −25.63/−12.02) (percentage −31.78%, 95% CI −41.45/−22.11). Similarly, GGT levels were reduced after statin treatment with an MD of −19.93 U/L (95% CI −27.10/−12.77) (percentage −25.57%, 95% CI −35.18/−15.97). Cross-sectional studies showed no difference in AST and GGT values between patients treated with and without statins. Conclusion: In interventional studies, ALT, AST and GGT were reduced after statin treatment with a percentage mean difference of −35.41%, −31.78% and −25.57%, respectively, while observational studies showed a null effect, suggesting liver safety of statins in NAFLD patients.