Association of body roundness index and age acceleration with type 2 diabetes: Evident from the UK Biobank

Background: Obesity and aging are regarded as significant risk factors for type 2 diabetes(T2D). However, joint effect of body roundness index (BRI) and age acceleration (ACC), novel predictors of visceral and the rate of aging, with incident T2D remains unclear. Objective: To examine the associations of BRI and ACC with incident T2D. Methods: This prospective cohort study used data from the UK Biobank, and participants with pre-existing diabetes and missing data were excluded in the analysis. The outcome of interest was incident T2D. Joint effect of BRI and ACC were assessed through eight paired quartile combinations. Kaplan-Meier curves were used to estimate cumulative incidence, while Cox proportional-hazards regression was used to analyze the independent and joint effect of BRI and ACC by gradually adjusting covariates. Results: Among 380,146 participants from the UK Biobank over 14.6 years of follow-up, 15,262 developed T2D. Kaplan-Meier survival curves indicated that participants with a higher level of BRI or ACC had a higher risk of T2D. Both BRI and ACC levels were positively associated with incident T2D (BRI:HR: 1.30, 95% CI: 1.28-1.32, ACC: HR: HR: 1.03, 95% CI: 1.03-1.03). When BRI and ACC were categorized into quartiles, those in the top quartile demonstrated a significantly increased T2D risk (BRI-Q4:HR:3.68, 95%CI: 3.35-4.04; ACC-Q4:HR:1.59, 95%CI:1.50-1.68; BRI-Q4 and ACC-Q4: HR: 6.76, 95% CI: 5.65-8.09). Conclusion: BRI and ACC were independently associated with increased risk of T2D, with BRI showing a stronger predictive capability. Their combined effects underscore their utility as non-invasive screening tools for T2D risk.