Obesity Predicts Liver Function Testing and Abnormal Liver Results

Abnormal liver function tests in children and young people (CYP) predict a greater burden of liver disease in adulthood, especially in the context of obesity. This study aimed to determine whether obesity and metabolic risk factors predict liver function testing and abnormal liver test results in CYP.

This was a retrospective cross-sectional population study using electronic health care records from 257,746 CYP aged 10 to 25 years who were registered with 170 contiguous general practices in London, UK. Demographic and clinical data were extracted, including serum alanine aminotransferase (ALT) tests between 2015 and 2017. BMI category thresholds were adjusted according to age group and ethnicity.

Fourteen percent of CYP had ALT measured, of whom 5.4% had abnormal results; 36.3% had BMI indicating overweight or obesity. Nonalcoholic fatty liver disease was the most common liver diagnosis. Multivariate analyses demonstrated that overweight or obesity was an independent predictor of ALT testing in young people (ages 18-25) but not in children (ages 10-17) and of abnormal test results in all CYP, irrespective of ALT threshold.

Overweight and obesity are predictors of liver testing (not in children) and abnormal test results, irrespective of ALT threshold. Given the rising prevalence of metabolic dysfunction, a coordinated strategy is needed for liver testing and interpreting results in this young population.