Abstract
PURPOSE: The World Health Organization (WHO) defines Intrinsic Capacity (IC) as the integration of an individual's physiological and psychological capacities. Encompassing five dimensions- locomotion, cognitive, vitality, psychological, and sensory function-it plays a central role in the assessment of healthy ageing. This study aimed to evaluate the association between IC and hip fractures among community-dwelling older adults in China. PATIENTS AND METHODS: This population-based longitudinal study analyzed data from 3102 community-dwelling residents aged ≥ 60 years in the China Health and Retirement Longitudinal Study (CHARLS), with baseline assessments conducted in 2011 and a 4-year follow-up through 2015. IC was assessed across five domains: cognitive, psychology, vitality, locomotion, and sensory function. The outcome measure was self-reported hip fracture, while demographic characteristics and other covariates were analyzed as potential confounders. Multivariable logistic regression models were employed to estimate adjusted odds ratios (ORs) with 95% confidence intervals (CI). The relationship between IC and hip fracture was further evaluated using restricted cubic splines and subgroup analyses. RESULTS: A total of 3,102 older adults (57.16% male) with a median age of 65.00 years were included. Over the 4-year follow-up, 96 participants (3.09%) experienced hip fractures. Regarding IC, the total IC score for the entire cohort was 1.56 ± 1.07(range 0-5, a total score of ≥ 2 is defined as IC impairment). The hip fracture group exhibited significantly higher IC scores compared to the non-fracture group (2.14 ± 1.06 vs.1.14 ± 1.06, p < 0.001). Baseline IC impairment (observed in 48.42% of participants) was associated with a 2.34-fold higher incidence of hip fracture compared to those without impairment (4.39% vs.1.88%). Analysis revealed that each 1-point increase in IC score among individuals aged ≥ 60 years was associated with a 55% elevated risk of hip fracture (adjusted OR = 1.55, 95% CI 1.25-1.94, p < 0.001). When stratified by IC status, the effect was more pronounced with IC-impaired. Compared to without impaired group, individuals with IC impairment had 87% higher risk of fracture (adjusted OR = 1.87, 95% CI 1.72-2.98, p = 0.009). Additionally, a linear relationship was demonstrated between IC and hip fracture risk. CONCLUSION: Among community-dwelling older adults, the composite IC score demonstrated a significant independent association with an elevated risk of hip fracture. Regular monitoring of individual IC scores may serve as an early warning indicator to initiate preventive interventions.