Non-alcoholic fatty liver disease in premenopausal women with polycystic ovary syndrome: A systematic review and meta-analysis

Background and aim: Non-alcoholic fatty liver disease (NAFLD) and polycystic ovary syndrome (PCOS) are prevalent conditions sharing common pathogenic factors. We performed a systematic literature review and meta-analysis aiming to investigate the association between NAFLD and PCOS among premenopausal PCOS patients.

Methods: Relevant studies were systematically identified from scientific databases until 2019. We calculated pooled odds ratio (OR) using a random-effect model, and heterogeneity was addressed through I ². Subgroup analyses and meta-regression for various covariates were performed.

Results: Of the 1833 studies retrieved, 23 studies with 7148 participants qualified for quantitative synthesis. The pooled result showed that women with PCOS had a 2.5-fold increase in the risk of NAFLD compared to controls (pooled OR 2.49, 95% confidence interval [CI] 2.20-2.82). In subgroup analyses comparing PCOS to controls, South American/Middle East PCOS patients had a greater risk of NAFLD (OR 3.55, 95% CI 2.27-5.55) compared to their counterpart from Europe (OR 2.22, 95% CI 1.85-2.67) and Asia (OR 2.63, 95% CI 2.20-3.15). Insulin resistance and metabolic syndrome were more frequent in the PCOS group (OR 1.97, 95% CI 1.44-2.71 and OR 3.39, 95% CI 2.42-4.76, respectively). Study quality and body mass index (BMI) were the only covariates that showed a relationship with the outcome in the meta-regression, with a regression coefficient of -2.219 (95% CI -3.927 to -0.511) and -1.929 (95% CI -3.776 to -0.0826), respectively.

Conclusions: This meta-analysis indicates that premenopausal PCOS patients are associated with 2.5-fold increase in the risk of NAFLD, and BMI seems to be the main cofactor.