Role of vitamin D in children with hepatosteatosis.

Background: The increasing incidence of obesity in children is a significant risk factor for nonalcoholic fatty liver disease and obesity-associated morbidity. Vitamin D has a major role in bone mineral metabolism and has antimicrobial, antioxidant properties. In this study we aimed to investigate the role of vitamin D in children with obesity with hepatosteatosis.

Methods: A total of 101 children with obesity were included in this study. Hepatosteatosis was diagnosed and graded using ultrasonography. Serum levels of 25-hydroxyvitamin D (25-(OH) vitamin D), calcium, phosphate, alkaline phosphatase, and parathormone were tested. Two-sided t test and Pearson χ tests were used for the relation between vitamin D and hepatosteatosis.

Results: In our study group, 45.5% were girls (n=46) and the mean age was 11.5 ± 2.8 years (range 3-17 years). Hepatosteatosis was identified in 58 children (57.4%). The diagnosis of grade 1 and grade 2 hepatosteatosis was made in 41 (40.6%) and 17 (16.8%) children, respectively. Median serum 25-(OH) vitamin D levels in children without hepatosteatosis was 16.4 ng/mL (interquartile range 12.4-24.8 ng/mL), whereas children with grade 1 and grade 2 hepatosteatosis had 25-(OH) vitamin D levels of 14.2 ng/mL (interquartile range 9.5-21.2 ng/mL) and 11.5 ng/mL (interquartile range 7.5-16.7 ng/mL), respectively (P=0.005). There was a positive correlation between insulin resistance and the grade of hepatosteatosis (P=0.03).

Conclusions: Serum vitamin D levels in children with obesity with hepatosteatosis are significantly lower than vitamin D levels in children with obesity without hepatosteatosis. In this observational study we only refer to the association of vitamin D deficiency/insufficiency with hepatosteatosis.