Background: Hypovitaminosis D is highly prevalent and has several adverse health effects. This study aims to assess the relationship of serum concentrations of 25?hydroxyvitamin D (25 [OH] D) and liver enzymes in adolescents.
Methods: This population?based cross?sectional survey was conducted among a nationally representative multistage sample of 1095 adolescents (52% boys), aged 10–18 years, living in different provinces of Iran. Serum 25 (OH) D concentration<30 ng/ mL was considered as hypovitaminosis D, and liver enzymes (alanine aminotransaminase [ALT] and aspartate aminotransaminase [AST]) of>40 U/L was considered as high level. To determine the association between serum 25 (OH) D categories and elevated levels of liver enzymes, multiple regression models and linear regression analysis were applied, after adjustment for potential confounders. Odds ratios (95% confidence interval) of serum 25 (OH) D and elevated liver enzymes were assessed by logistic regression analysis.
Results: Higher rates of Vitamin D deficiency were documented among individuals with increased levels of liver enzymes. Compared to boys, median of 25 (OH) D was lower in girls with elevated levels of liver function tests (12.75 vs.25.60 ng/mL for ALT and 13 vs.14.10 ng/mL for AST), with marginally significant gender differences regarding AST.
Conclusions: We found a relatively high frequency of hypovitaminosis D among adolescents with abnormal liver function. Further prospective studies are needed to examine these associations from early life.