Non-alcoholic fatty liver disease in overweight children and its relationship with retinol serum levels

Objectives: To evaluate the frequency of non-alcoholic fatty liver disease, the retinol serum levels, lipid profile, and insulin resistance in overweight/obese children. To relate these biochemical variables with the risk of this disease in the population studied. Methods: The study was cross-sectional and prospective, with 46 overweight/obese school children (28 female, 18 male; mean age 8.6 years). The control group consisted of 45 children, paired by age and gender. Hepatic steatosis, evaluated by ultrasound, was classified as normal, mild, moderate, or severe. Also evaluated were serum retinol levels; thiobarbituric acid reactive substances; lipid profile; and fasting glucose and serum insulin levels, used for the calculation of the Homeostasis Model Assessment. Results: Hepatic ultrasound alterations were found in 56.5% and 48,9% of the overweight/obese and control group children, respectively. Presence of obesity was associated with-high levels of triglycerides (OR = 4.6; P 0.002). In the studied children, the risk of steatosis was related to a trend to a higher percentage of retinol inadequacy (OR = 2.8; p = 0.051); there was no association with thiobarbituric acid reactive substances, lipid profile, or insulin resistance. Conclusions: The high frequency of non-alcoholic fatty liver disease in both groups, evaluated by hepatic ultrasound, in low-socioeconomic level children, independent of nutritional condition and without significant association with insulin resistance, emphasizes that especially-in-developing countries, other risk factors such as micronutrient deficiencies (e.g. vitamin A) are involved.