Body roundness index and cardiometabolic multimorbidity: Findings from the English Longitudinal Study of Ageing.

BACKGROUND AND AIMS: Evidence on the association of Body Roundness Index (BRI), an anthropometric indicator of body fat and visceral adiposity, with cardiometabolic multimorbidity (CMM) remains limited. This study aimed to compare the associations and predictive utilities of BRI and body mass index (BMI) for CMM.

METHODS AND

RESULTS

We analyzed data from 3348 adults (mean age 63 years; 45.1 % male) in the English Longitudinal Study of Ageing, free of major cardiometabolic conditions at baseline (2008-2009). BRI was derived from height and waist circumference. CMM was defined as having ≥2 of the following by 2021-2023: hypertension, cardiovascular disease, diabetes, or stroke. Multivariable odds ratios (ORs) and 95 % confidence intervals (CIs) were estimated. During 12-15 years of follow-up, 197 participants (5.9 %) developed CMM. Both BRI and BMI showed linear dose-response relationships with CMM risk (p for nonlinearity >0.05). Higher BRI was associated with increased odds of CMM (per 1-SD: OR 1.33, 95 % CI 1.17-1.53; top vs bottom tertile: OR 1.89, 95 % CI 1.23-2.90), with similar findings for BMI. Adding BRI to conventional risk models modestly improved discrimination (ΔC-index = 0.0082, p = .26) and significantly improved model fit (p < .001). Gains for BMI were smaller (ΔC-index = 0.0049, p = .46), with BRI offering a slightly greater improvement in predictive performance (Δ = 0.0033, p = .40).

CONCLUSION

Both BRI and BMI were independently and linearly associated with an increased risk of CMM. BRI showed slightly stronger predictive performance than BMI.