Associations between serum total, free and bioavailable testosterone and non-alcoholic fatty liver disease in community-dwelling middle-aged and elderly women

BACKGROUND AND AIMS Non-alcoholic fatty liver disease (NAFLD) is considered both a cause and consequence of the metabolic syndrome (MetS). While emerging evidence has indicated that testosterone is associated with MetS, the relationship between testosterone and NAFLD in women remains unclear. Therefore, this study investigated the associations between serum testosterone levels and NAFLD prevalence risk in a community-based cross-sectional study. METHODS A total of 2117 adult women were included in the analysis. Serum total testosterone (TT) was measured by chemiluminescence immunoassay, and other testosterone-related indices, such as concentrations and percentages of calculated free testosterone (cFT) and bioavailable testosterone (BioT), and free androgen index (FAI), were also calculated. NAFLD was diagnosed by clinical criteria. Logistic regression was used to explore these associations. RESULTS There were significant differences in TT, FAI, cFT and BioT between women with and without NAFLD (all P <  0.001). Multivariate logistic-regression analyses demonstrated that both absolute concentrations and percentages of cFT and BioT were positively associated with NAFLD risk prevalence in all models. Adjusted ORs (95% CI) for quartile 4 vs quartile 1 of % cFT and % BioT were 5.94 (4.29-8.22) and 5.21 (3.79-7.17) in model 2, and 4.35 (3.07-6.18) and 3.58 (2.55-5.03) in model 3 (all P <  0.001 for trend). In addition, quartiles of TT, FAI, cFT and BioT were significantly correlated with degree of hepatic steatosis. ROC analysis also showed that % cFT and % BioT were more accurate for predicting NAFLD prevalence than was TT. CONCLUSION Serum cFT and BioT were positively associated with NAFLD risk, and elevated levels of cFT and BioT could be independent risk factors of NAFLD prevalence in middle-aged and elderly women.