Depression and increased risk of nonalcoholic fatty liver disease in individuals with obesity

Aims. The longitudinal relationship between depression and the risk of nonalcoholic fatty liver disease (NAFLD) is uncertain. We examined: a) the association between depressive symptoms and incident hepatic steatosis (HS), both with and without liver fibrosis; and b) the influence of obesity on this association. Methods. A cohort of 142,005 Korean adults with neither HS nor excessive alcohol consumption at baseline were followed for up to 8.9 years. The validated Center for Epidemiologic Studies-Depression score (CES-D) was assessed at baseline, and subjects were categorized as non-depressed (a CES-D <8, reference) or depression (CES-D ≥16). HS was diagnosed by ultrasonography. Liver fibrosis was assessed by the fibrosis-4 index (FIB-4). Parametric proportional hazards models were used to estimate the adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). Results. During a median follow-up of 4.0 years, 27,810 people with incident HS and 134 with incident HS plus high FIB-4 were identified. Compared with the non-depressed category, the aHR (95% CIs) for incident HS was 1.24 (1.15-1.34) for CES-D ≥16 among obese individuals, and 1.00 (0.95-1.05) for CES-D ≥16 among non-obese individuals (P for interaction with obesity <0.001). The aHR (95% CIs) for developing HS plus high FIB-4 was 3.41 (1.33-8.74) for CES-D≥16 among obese individuals, and 1.22 (0.60-2.47) for CES-D≥16 among non-obese individuals (P for interaction =0.201). Conclusions. Depression was associated with an increased risk of incident HS and HS plus high probability of advanced fibrosis, especially among obese individuals.