Age-related insulin resistance changes in children and adolescents and its impact on the accuracy of diagnosis of metabolic syndrome.

PURPOSE

Although insulin resistance (IR) varies with age and puberty in children and adolescents, most previous attempts to determine cutoff values for IR indices overlook factor. This study assesses age-related differences in IR index values and evaluates how diagnostic performance varies by age when using a uniform cutoff for diagnosing metabolic syndrome (MetS) without considering age.

METHODS

We analyzed age-related differences in IR indices (the homeostatic model assessment of insulin resistance [HOMA-IR], triglyceride-glucose [TyG] index, and triglyceride/high-density lipoprotein cholesterol [TG/HDL-C] ratio) among 1,641 participants in the 2019-2021 Korea National Health and Nutrition Examination Survey. We also examined IR index values for diagnosing MetS in 1,574 participants.

RESULTS

IR indices showed significant age-related variations in group-comparison tests, with a peak at ages 12-13 years in males and 11-13 years in females (P<0.001 for the HOMA-IR, P<0.005 for the TG/HDL-C ratio in both males and females, and P=0.003 for the TyG index in females). Applying a uniform cutoff derived from receiver operating characteristic curve analysis for diagnosing MetS showed substantial age-related variation in diagnostic accuracy, with standard deviation-to-mean ratios of age-specific accuracy of >10% for the HOMA-IR and >5% for the TyG index, while showing minor variation (<5%) for the TG/HDL-C ratio. Using age-specific percentiles for the HOMA-IR (80th of the general population) and TyG index (80th of those without MetS) reduced these variations to <5% while maintaining similar diagnostic performance.

CONCLUSION

This study highlights the importance of age-related variation in IR in children and adolescents.