Association between physical function and type 2 diabetes risk in older adults: a longitudinal analysis from the KoGES-Anseong cohort

PURPOSE: Type 2 diabetes (T2D) is associated with functional decline in older adults, but whether baseline physical function predicts its incidence remains unclear. This study examined whether the Short Physical Performance Battery (SPPB) predicts incident T2D in older Koreans, and whether resting heart rate (RHR) modifies this association. METHODS: We included 1,041 community-dwelling adults aged ≥ 65 years (mean age = 72.2 years; 58.3% women) without T2D at baseline from the KoGES-Anseong cohort (2013-2020). SPPB scores were categorized as high (≥ 10) or low (< 10), and RHR was dichotomized at the median. Incident T2D was ascertained through fasting glucose, physician diagnosis, or diabetes medication. Cox proportional hazards models (adjusted for demographic, metabolic, and lifestyle factors) estimated hazard ratios (HRs) and 95% confidence intervals (CIs) over 5294 person-years of follow-up. RESULTS: High SPPB scores were associated with a lower risk of T2D (HR = 0.49, 95% CI 0.25-0.94). This association was observed only in participants with elevated RHR (HR = 0.37, 95% CI 0.17-0.81), but not in those with lower RHR. Among individual SPPB domains, only lower-extremity strength showed a significant association with reduced T2D risk. CONCLUSION: In older adults, superior physical function substantially reduces the risk of T2D, with lower-extremity strength as the primary contributor. Importantly, this benefit remains robust among individuals with elevated RHR, underscoring functional performance as a practical target for preventive strategies.