Low Vitamin D Level was Associated with Non-alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus

Abstract

Background: Non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are major public health concerns. Besides the known risk factors, other risk factors, such as vitamin D deficiency, have been suggested for NAFLD. Objectives: This cross-sectional research aimed to investigate the relationship between serum vitamin D levels and NAFLD in a group of patients with T2DM. Methods: We investigated various clinical and biochemical parameters, including serum vitamin D level, liver function tests, and liver sonography in 1,110 adult patients with T2DM. The mean difference of numerical variables in NAFLD and non-NAFLD groups was analyzed with an independent sample t-test. Chi-square test was used to evaluate the association between two categorical variables. Results: Out of 1,110 patients with T2DM, 837 (75.4%) had NAFLD. The mean vitamin D level in diabetic patients with NAFLD was significantly lower than non-NAFLD group (19.71 ng/mL vs. 27.68 ng/mL, respectively; P < 0.001). Furthermore, 410 (49%) patients with NAFLD were found with vitamin D deficiency, while this value was 85 (31.1%) in non-NAFLD group. According to the results of univariate logistic regression analysis, vitamin D deficiency (OR = 3.87) and insufficient vitamin D (OR = 2.83) were the significant variables for NAFLD. Conclusions: There was a significant association between vitamin D deficiency and NAFLD in patients with T2DM.