Determinants of frailty development and progression using a multidimensional frailty index: evidence from the English Longitudinal Study of Ageing

Objective: To identify modifiable risk factors for development and progression of frailty in older adults living in England, as conceptualised by a multidimensional frailty index (FI).

Methods: Data from participants aged 50 and over from the English Longitudinal Study of Ageing (ELSA) was used to examine potential determinants of frailty, using a 56-item FI comprised of self-reported health conditions, disabilities, cognitive function, hearing, eyesight, depressive symptoms and ability to carry out activities of daily living. Cox proportional hazards regression models were used to measure frailty development (n = 7420) and linear regression models to measure frailty progression over 12 years follow-up (n = 8780).

Results: Increasing age (HR: 1.08 (CI: 1.08-1.09)), being in the lowest wealth quintile (HR: 1.79 (CI: 1.54-2.08)), lack of educational qualifications (HR: 1.19 (CI: 1.09-1.30)), obesity (HR: 1.33 (CI: 1.18-1.50) and a high waist-hip ratio (HR: 1.25 (CI: 1.13-1.38)), being a current or previous smoker (HR: 1.29 (CI: 1.18-1.41)), pain (HR: 1.39 (CI: 1.34-1.45)), sedentary behaviour (HR: 2.17 (CI: 1.76-2.78) and lower body strength (HR: 1.07 (CI: 1.06-1.08)), were all significant risk factors for frailty progression and incidence after simultaneous adjustment for all examined factors.

Conclusion: The findings of this study suggest that there may be scope to reduce both frailty incidence and progression by trialling interventions aimed at reducing obesity and sedentary behaviour, increasing intensity of physical activity, and improving success of smoking cessation tools. Furthermore, improving educational outcomes and reducing poverty may also reduce inequalities in frailty.