Longitudinal characteristics of physical frailty and its components in men and women post hip fracture

Abstract

Background Frailty is an important geriatric syndrome predicting adverse health outcomes in older adults. However, the longitudinal characteristics of frailty components in post-hip fracture patients are less understood. Adopting the Fried frailty definition, we examined the longitudinal trends and sex trajectory differences in frailty and its components over 1 year post-fracture.

Methods Three hundred and twenty-seven hip fracture patients (162 men and 165 women with mean age 80.1 and 81.5) from Baltimore Hip Studies 7th cohort with measurements at 22 days after admission, and months 2, 6, and 12 post-fracture were analyzed. Frailty components included: grip strength, gait speed, weight, total energy expenditure, and exhaustion. Longitudinal analysis used mixed effect models.

Results At baseline, men were sicker with worse cognitive status, and had higher weight and grip strength, but lower total energy expenditure than women (p < 0.001). The prevalence of frailty was 31.5%, 30.2%, and 28.2% at months 2, 6, and 12 respectively, showing no longitudinal trends or sex differences. However, its components showed substantial recovery trends over the post-fracture year after confounding adjustments, including increasing gait speed, reducing risk of exhaustion, and stabilized weight loss and energy expenditure over time. Particularly, while men's grip strength tended to remain stable over first year post surgery within patients, women's grip strength reduced significantly over time within patients. On average over time within patients, women were more active with higher energy expenditures but lower grip strength and weight than men.

Conclusion Significant recovery trends and sex differences were observed in frailty components during first year post-fracture. Overall frailty status did not show those trends over months 2–12 since a summary measure might obscure changes in components. Therefore, frailty components provided important multi-dimensional information on the complex recovery process of patients, indicating targets for intervention beyond the global binary measure of frailty.