A body shape index is a better predictor of overall and cardiovascular mortality than body mass index: Results from the ENAH study.

INTRODUCTION

Body mass index (BMI) is commonly used to estimate obesity-related risk, but it does not reflect fat distribution. A Body Shape Index (ABSI), which captures central adiposity independently of BMI, may offer better prognostic value. We compared ABSI and BMI as predictors of all-cause and cardiovascular (CV) mortality in a general rural population.

METHODS

This prospective analysis included 820 participants from the ENAH (Endemic Nephropathy in Croatia - Epidemiology, Diagnostics and Etiopathogenesis) cohort with complete baseline anthropometric data. BMI and ABSI were calculated at baseline and expressed as z-scores. Participants were followed for a median of 9.7 years. Associations with all-cause mortality, CV mortality, and a composite non-fatal outcome were examined using multivariable Cox regression. Discriminative ability was assessed by receiver operating characteristic analysis.

RESULTS

Higher ABSI was independently associated with increased all-cause mortality (hazard ratio per 1-SD increase 1.15, 95% confidence interval 1.01-1.32) and CV mortality (1.27, 1.04-1.55), whereas BMI showed no significant association with either outcome. Mortality risk increased across ABSI tertiles but not BMI tertiles. ABSI demonstrated better discrimination for all-cause and CV mortality than BMI, while neither index predicted non-fatal outcomes.

CONCLUSION

ABSI outperformed BMI in predicting all-cause and CV mortality. Measures of central adiposity such as ABSI may improve mortality risk stratification beyond BMI alone.