Publication:

Beyond BMI: association of body roundness, abdominal volume, conicity and body shape indices with insulin resistance and metabolic risk in urban Indian adolescents and adults

Background Body roundness index (BRI), Abdominal volume index (AVI), Conicity index (CI), and a body shape index (ABSI) have been proposed as improved predictors of adiposity and metabolic risk. This study evaluated gender differences, age-related trends, diagnostic performance and associations of these indices with adiposity and metabolic parameters.

Methods A cross-sectional analysis was conducted among 1,998 apparently healthy Indian adolescents and adults (620 males and 1,378 females;16–55 years) from the Mumbai Metropolitan Region. Anthropometric measurements, body composition, and biochemical parameters were assessed. BRI, AVI, CI, and ABSI were calculated. Gender differences were compared using independent t-tests, age-related trends across quintiles, receiver operating characteristic analysis assessed diagnostic accuracy, and Pearson's correlation examined associations with metabolic parameters.

Results Adiposity indices increased significantly with age, whereas muscle mass declined (p<0.001). Females had higher BMI, waist-to-height ratio, body fat percentage, and BRI, while males had higher waist circumference, waist-to-hip ratio, visceral fat, muscle mass, AVI, CI, and ABSI (all p<0.01). BRI showed the highest accuracy for identifying obesity (AUC=0.953) and central obesity (AUC=1.000), followed by AVI. Both BRI and AVI correlated with adiposity measures, fasting glucose, fasting insulin, HbA1c, and HOMA-IR (all p<0.001). AVI was independently associated with HOMA-IR and fasting insulin, whereas BRI was associated with the fasting glucose-to-insulin ratio.

Conclusion BRI and AVI are reliable, low-cost markers of adiposity and early metabolic dysfunction. BRI showed superior diagnostic accuracy for obesity, whereas AVI demonstrated stronger associations with insulin resistance, supporting their use in early cardiometabolic risk screening among apparently healthy Indian populations.