BACKGROUND: Incretin hormones, including glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), along with glucagon, are regulators of appetite, energy balance, and fat metabolism. Despite their recognized functions, reference values for these hormones in children have not previously been established. This study aimed to establish age- and sex-specific reference percentiles and z-scores for GLP-1, GIP, and glucagon in children and to examine their associations with insulin resistance, lipid status, and metabolic syndrome.
METHODS: Data were derived from the cohort of the study Childhood Health, Activity, and Motor Performance School Study Denmark (CHAMPS study DK) including 485 school children without metabolic syndrome.
RESULTS: Age was positively associated with GLP-1 levels in both sexes, while GIP levels showed an inverse relationship with age in girls. Insulin sensitivity, as measured by Homeostatic Model Assessment 2 for Insulin Resistance (HOMA2-IR), was positively associated with GLP-1 z-scores in boys and glucagon z-scores in girls.
CONCLUSION: Age, sex and insulin sensitivity are important determinants of incretin and glucagon hormone levels in children. The reference percentiles and z-scores generated in this study provide a framework for future studies in pediatric metabolic health and disease.
IMPACT: This study provides age- and sex-specific reference values for glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon in children and adolescents. This is the first publication presenting percentiles and z-scores for GLP-1 and GIP in children which is of value for future pediatric comparisons. Knowledge about normal physiology is of major importance for future research in the upcoming area of GLP-1, GIP and glucagon as potential biomarkers for metabolic disorders.
