Association between serum vitamin D and depression among non-alcoholic fatty liver disease.

Background and objectives: While previous population-based studies have suggested a link between serum vitamin D levels and depression in individuals with non-alcoholic fatty liver disease (NAFLD), the exact correlation between serum vitamin D and depression among NAFLD patients remains controversial and disputed. Thus, we conducted this study to evaluate the relationship between serum vitamin D and depression in NAFLD participants diagnosed via transient elastography.

Methods and study design: This cross-sectional study was extracted from the latest NHANES 2017-2018 dataset. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9) score of ≥10. NAFLD phenotype was identified by vibration-controlled transient elastography (VCTE) examination based on diagnostic criteria. Binary logistic regression models were applied to estimate the impact of increased serum vitamin D on the reduced risk of depression based on sample weights.

Results: A total of 1339 participants with NAFLD were included in this investigation, of which 127 (8.58%) were diagnosed with depression according to PHQ-9 scores. Binary logistic regression analysis presented that high serum vitamin D level was a protective factor for depression in NAFLD (OR=0.61, 95% CI: 0.37-0.99, p=0.048) after adjusting for all confounding factors. In subgroup analyses, these associations were more pronounced among men (OR=0.32, 95% CI: 0.13-0.81, p=0.024) and obese population (OR=0.53, 95% CI: 0.33-0.86, p=0.019).

Conclusions: Increased serum vitamin D was negatively associated to the prevalence of depression in males and obese individuals with NAFLD diagnosed by VCTE.