Ability of Self-Reported Frailty Components to Predict Incident Disability, Falls, and All-Cause Mortality: Results From a Population-Based Study of Older British Men

Abstract

Background: Frailty is a state of increased vulnerability to disability, falls, and mortality. The Fried frailty phenotype includes assessments of grip strength and gait speed, which are complex or require objective measurements and are challenging in routine primary care practice. In this study, we aimed to develop a simple assessment tool based on self-reported information on the 5 Fried frailty components to identify older people at risk of incident disability, falls, and mortality.

Methods: Analyses are based on a prospective cohort comprising older British men aged 71-92 years in 2010-2012. A follow-up questionnaire was completed in 2014. The discriminatory power for incident disability and falls was compared with the Fried frailty phenotype using receiver operating characteristic-area under the curve (ROC-AUC); for incident falls it was additionally compared with the FRAIL scale (fatigue, resistance, ambulation, illnesses, and loss of weight). Predictive ability for mortality was assessed using age-adjusted Cox proportional hazard models.

Results: A model including self-reported measures of slow walking speed, low physical activity, and exhaustion had a significantly increased ROC-AUC [0.68, 95% confidence interval (CI) 0.63-0.72] for incident disability compared with the Fried frailty phenotype (0.63, 95% CI 0.59-0.68; P value of ΔAUC = .003). A second model including self-reported measures of slow walking speed, low physical activity, and weight loss had a higher ROC-AUC (0.64, 95% CI 0.59-0.68) for incident falls compared with the Fried frailty phenotype (0.57, 95% CI 0.53-0.61; P value of ΔAUC < .001) and the FRAIL scale (0.56, 95% CI 0.52-0.61; P value of ΔAUC = .001). This model was also associated with an increased risk of mortality (Harrell's C = 0.73, Somer's D = 0.45; linear trend P < .001) compared with the Fried phenotype (Harrell's C = 0.71; Somer's D = 0.42; linear trend P < .001) and the FRAIL scale (Harrell's C = 0.71, Somer's D = 0.42; linear trend P < .001).

Conclusions: Self-reported information on the Fried frailty components had superior discriminatory and predictive ability compared with the Fried frailty phenotype for all the adverse outcomes considered and with the FRAIL scale for incident falls and mortality. These findings have important implications for developing interventions and health care policies as they offer a simple way to identify older people at risk of adverse outcomes associated with frailty.

Keywords: Frailty; disability; falls; mortality.