The Relationship Between Serum Levels of Vitamin D and Some Metabolic Indicators in Patients with Non-Alcoholic Fatty Liver Disease Referred to Sheikh Alreis Clinic in Tabriz: A Descriptive Study

Since vitamin D has been shown to have an important function in the regulation of metabolic pathways, this study aimed to investigate the association between serum levels of vitamin D with a number of metabolic indicators in patients with non-alcoholic fatty liver disease (NAFLD).

This descriptive study was conducted on 122 patients with NAFLD referred to Sheikh Alreis Clinic in Tabriz, who were categorized into "vitamin D sufficient" (n=46) and "vitamin D deficient" (n=76) based on their serum vitamin D concentrations. NAFLD was diagnosed by upper abdomen ultrasonography, and the fasting serum concentrations of glucose (FBS), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), high- density lipoprotein cholesterol (HDL-c) as well as Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) were measured as metabolic markers. Serum concentration of liver transaminase enzymes and liver steatosis severity were assessed as liver function criteria.

Serum concentrations of insulin (p=0.024), LDL-c (p<0.001), and HOMA-IR (p=0.011) were significantly higher in the NAFLD patients with vitamin D deficiency compared to the patients with sufficient vitamin D. Moreover, vitamin D deficient patients had higher NAFLD histologic severity (p=0.042) and serum concentrations of alanine aminoteransferase (ALT) compared to the NAFLD patients with vitamin D sufficiency (p=0.005). Vitamin D-deficient patients were at higher odds for having hypercholesterolemia (p=0.009) and high LDL-c (p=0.011) than ones with sufficient vitamin D status even when adjusted for confounders.

Vitamin D deficiency in the patients with NAFLD was found to be associated with higher odds of an unfavorable lipid profile and NAFLD histologic severity.