Association of intrinsic capacity with incident type 2 diabetes mellitus in older Chinese: Guangzhou Biobank Cohort Study

Background: The World Health Organization introduced intrinsic capacity (IC) as a metric for healthy aging. However, we found no report on the association between IC and type 2 diabetes mellitus (T2DM). We investigated the association between IC and incident T2DM in older Chinese from the Guangzhou Biobank Cohort Study. Methods: IC was assessed across five domains equally: locomotion, vitality, cognition, psychological and sensory. Composite IC scores (0–10) were classified into three groups: poor (0–5.9), fair (6.0–8.9), and high (9.0–10), with higher scores representing greater IC. Multivariable linear regression and cox regression was used to analyze the association between IC with glycemia and T2DM, respectively. Results: Of 3582 participants with a mean age of 59.1 years (standard deviation (SD)=7.13) without baseline diabetes, during an average follow-up of 3.3 years (SD=0.86), 497 (13.87%) developed T2DM. After adjustments for potential confounders, those with baseline poor IC, versus high, had higher fasting glucose, 2-hour post-load glucose and glycosylated hemoglobin A_1c at follow-up, and a higher risk of incident T2DM (HR (95%CI): 1.80 (1.20, 2.72)). Among IC domains, only vitality impairment was associated with an increased risk of T2DM (P for trend < 0.001). Conclusion: We first reported the prospective associations of poor IC and vitality with higher glycemia and incident T2DM risk. Enhancing muscle strength to improve functional ability may be a possible intervention for reducing future risk of T2DM in older populations.