Background

Timing of peak glucose concentrations during an Oral Glucose Tolerance Test (OGTT) is associated with increased risk for diabetes and cardiovascular disease.Whether the same holds for non-alcoholic fatty liver disease (NAFLD) risk is unknown. The purpose of this study is to compare risk markers of NAFLD between established glucose peak phenotypes in Latino youth with obesity.

Methods

149 Latino youth with obesity (15.3±0.9 years, BMI%=98.2±1.4) were phenotyped for peak glucose concentrations during a 5-sample, 2-hour OGTT. Two groups were defined as exhibiting a peak glucose concentration at 30 minutes (Early Peak) or peaking at or after 60 minutes (Late Peak). Fasting alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were assessed as indicators of NAFLD risk.

Results

55 (36.9%) youth exhibited the Early Peak phenotype and 94 (63.1%) exhibited the Late Peak phenotype. There were no significant differences in age (p=0.291), sex (p=0.855), BMI (p=0.438), BMI% (p=0.346), or waist circumference (p=0.276) between the two groups. Compared to the Early Peak group, the Late Peak group exhibited significantly higher circulating concentrations of ALT (19.9±1.4 IU/L vs. 22.2±1.4 IU/L, p=0.018) and AST (19.2±1.8 IU/L vs. 22.2±1.7 IU/L, p=0.034). The differences in ALT and AST between Early and Late Peak groups were independent of age, sex, and adiposity.

Conclusions

Latino youth with obesity who exhibit a delayed peak glucose concentration may be at increased risk for developing NAFLD.