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

During 12-15 years of follow-up, 5.9% of participants developed cardiometabolic multimorbidity (CMM).

• 197 out of 3348 participants developed CMM
• Study population had a mean age of 63 years with 45.1% male
• Participants were free of major cardiometabolic conditions at baseline (2008-2009)
• CMM was defined as having ≥2 of the following: hypertension, cardiovascular disease, diabetes, or stroke
• Follow-up extended to 2021-2023

Higher BRI was significantly associated with increased odds of developing CMM.

• Per 1-SD increase in BRI: OR 1.33, 95% CI 1.17-1.53
• Top versus bottom tertile of BRI: OR 1.89, 95% CI 1.23-2.90
• BRI was derived from height and waist circumference
• The association was linear (p for nonlinearity >0.05)

BMI showed similar associations with CMM risk as BRI.

• Both BRI and BMI showed linear dose-response relationships with CMM risk (p for nonlinearity >0.05)
• Similar findings for BMI were observed as for BRI in multivariable analyses
• Results were estimated using multivariable odds ratios and 95% confidence intervals

Adding BRI to conventional risk models modestly improved discrimination and significantly improved model fit.

• Adding BRI improved discrimination: ΔC-index = 0.0082, p = .26
• Adding BRI significantly improved model fit: p < .001
• Adding BMI produced smaller gains in discrimination: ΔC-index = 0.0049, p = .46
• BRI offered a slightly greater improvement in predictive performance compared to BMI: Δ = 0.0033, p = .40

BRI showed slightly stronger predictive performance for CMM than BMI, though the difference was not statistically significant.

• The difference in C-index improvement between BRI and BMI was 0.0033
• The p-value for this difference was .40, indicating it was not statistically significant
• BRI is an anthropometric indicator of body fat and visceral adiposity
• Evidence on the association of BRI with CMM was described as limited prior to this study