Comparison of obesity indices for discriminating hypertension, diabetes, dyslipidemia, and metabolic syndrome according to sex and age groups.

INTRODUCTION

This study compared the discriminatory performance of seven obesity indices for metabolic diseases by sex and age.

METHODS

We analyzed data from 8900 Korean adults aged ≥ 20 years using the 2022-2023 Korea National Health and Nutrition Examination Survey. Seven obesity indices (body mass index, waist circumference, waist-to-height ratio, a body shape index, body roundness index, fat mass index, and body fat percentage) were evaluated in relation to hypertension, diabetes, dyslipidemia, and metabolic syndrome. Associations and discriminatory ability were assessed using logistic regression and receiver operating characteristic analyses stratified by sex and age.

RESULTS

Central obesity indices, particularly waist-to-height ratio and body roundness index, showed the strongest associations with all metabolic outcomes in both sexes. A body shape index exhibited weaker associations after age adjusted. Discriminatory performance declined with age across all indices, especially after 50 years.

CONCLUSIONS

Waist-to-height ratio, body roundness index, and waist circumference were superior to body mass index and comparable to fat mass index and body fat percentage in identifying metabolic risk, particularly in younger and middle-aged adults. The reduced discriminatory power in older adults underscores the need for age-sensitive obesity metrics and complementary functional assessments.