Early Obesity: Risk Factor for Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD), defined as fat accumulation greater than 5% in hepatocytes, may progress to fibrosis or cirrhosis later in life. NAFLD prevalence in adolescents has increased significantly in direct relation with obesity prevalence. Fatty liver has become the most frequent indication for liver transplantation in adults.

The aim of the study was to identify anthropometric variables during the first 10 years of life associated to the risk of developing NAFLD in adolescence.

Longitudinal cohort study 'Growth and Obesity Chilean Cohort Study' (GOCS) consisting of 513 children born in 2002 to 2003, with yearly anthropometric data collected over a 10-year period. The presence of intrahepatic fat in the livers of subjects 14 to 16 years of age was determined using abdominal ultrasound. In addition, elastography was performed on all participants with ultrasound evidence of NAFLD.

9.7% of the participants presented findings compatible with NAFLD. After 2 years of age, obesity significantly and progressively increased the probability of NAFLD occurrence in adolescence. Obesity at 5 years of age was associated with the highest OR for NAFLD, reaching values of 8.91 (95% CI 3.03-16.11). Among participants with NAFLD, those with altered liver elasticity (≥7 kPa) had greater weight, BMI z-score, waist and hip circumference, and altered liver enzymes (P < 0.05).

The risk of developing NAFLD in adolescence increases progressively with early obesity starting at age 2 years.