Overweight, obesity tied to higher liver biochemical markers in youths

Children and adolescents who are overweight or obese tend to have elevated biochemical markers of liver damage, a study has shown. Moreover, variations in paediatric normal values of liver enzymes exist across age and sex groups.

Participants were recruited from two cohorts of Danish youths: 1,858 from a population-based cohort and 2,155 with overweight or obesity, aged 6–18 years. The authors calculated age- and sex-specific percentile curves for the following markers: fasting plasma concentrations of alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), gamma-glutamiltransferase (GGT), bilirubin and alkaline phosphatase (ALP) in both cohorts. Proton magnetic resonance spectroscopy was used in 458 participants to assess their hepatic fat content.

Concentrations of ALT, AST, LDH and ALP decreased with age in both girls and boys. On the other hand, GGT and bilirubin concentrations increased slightly with age in boys and were similar across age groups in girls. Overweight and obesity were associated with higher concentration of ALT in all age groups. Concentrations of ALT, and to some extent GGT, increased with age in overweight or obese boys.

In addition, the optimal ALT cut-points for diagnosis hepatic steatosis (liver fat content >5 percent) was 24.5 U/L for girls (sensitivity, 55.6 percent; specificity, 84.0 percent) and 34.5 U/L for boys (sensitivity, 83.7 percent; specificity, 68.2 percent).

“These findings emphasize the need for prevention and treatment of overweight and obesity in children and adolescents,” the authors said.

“Elevated plasma concentrations of liver enzymes are routinely used as markers of liver injury in adults and children,” they added.