Age and sex-specific waist circumference percentiles among school children in Chennai

Background: The aim was to develop age- and sex-specific waist circumference percentiles for school children aged 5 to 17 years in Chennai. Methods: This was a cross-sectional study done among school children in Chennai. A total of 1124 children aged 5 to 17 years were included in the study, of which 540 were female and 584 were male. Anthropometric details, weight, height, waist circumference (WC), and body mass index (BMI) were measured. The percentiles for waist circumference according to age and gender was done using SPSS 28.0. Khadilkar et al suggested a cutoff of 70th centile screening for central obesity and risk for metabolic syndrome; similarly, we plotted 70th WC percentiles. Results: Age- and sex-specific WC percentiles (5th, 10th, 15th, 25th, 50th, 75th, 85th, 90th, 95th) were provided. Our study revealed a higher prevalence of overweight or obesity (40.6%) in children (overweight: 21.08%, obesity: 19.50%) when compared to other school studies. BMI in children with WC >70th percentile revealed 87% of them were overweight or obese. A strong and significant statistical correlation was observed between waist circumference and overweight or obesity (p<0.001). Conclusions: Age- and sex-specific reference curve percentiles for waist circumference and cut-off values greater than the 70th percentile for schoolchildren were provided. We strongly recommend utilising waist circumference as an anthropometrical tool to quantify central obesity in schoolchildren.