Association between body roundness index trajectories and the risk of cardiometabolic multimorbidity in Chinese middle-aged and older adults: Evidence from the China health and retirement longitudinal study

Abstract

Background

Cardiometabolic multimorbidity (CMM) is a growing global public health concern, particularly among aging populations. Body Roundness Index (BRI), a novel anthropometric measure reflecting visceral adiposity, may outperform BMI in predicting cardiometabolic risk. This study aimed to investigate the association between longitudinal BRI trajectories and the risk of CMM in a longitudinal cohort.

Methods

8412 participants were ultimately selected from in the China Health and Retirement Longitudinal Study database. BRI measurements were repeatedly obtained from these participants between 2011 and 2016. Group-based trajectory modeling (GBTM) was applied to identify BRI trajectories from 2011 to 2016, with CMM between 2017 and 2020 designated as the primary outcome. We executed a Cox proportional hazards regression model to assess the association between BRI trajectories and the incidence of CMM. In the sensitivity analysis, we stratified cumulative BRI into quartiles to assess whether the association with CMM remained consistent.

Results

Based on the GBTM, participants were categorized into three distinct BRI trajectory groups. These groups, labeled Low-stable, Moderate-stable, and High-stable, comprised 48.23 %, 42.21 %, and 9.56 % of the study population, respectively. Compared to the Low-stable group, Moderate-stable (HR = 1.99, 95 % CI: 1.69–2.35) and High-stable (HR = 2.88, 95 % CI: 2.28–3.63) groups had significantly increased risks of CMM. Subgroup analyses revealed a significant interaction between BMI level and BRI trajectory on CMM outcomes. Sensitivity results supported these findings.

Conclusion

Persistently high BRI trajectories significantly increase CMM risk. BRI is a simple, noninvasive marker with public health utility for early identification and prevention of cardiometabolic diseases, especially in resource-limited settings.