The contribution of multiple long-term conditions to widening inequalities in disability-free life expectancy over two decades: Longitudinal analysis of two cohorts using the Cognitive Function and Ageing Studies

Elsevier, EClinicalMedicine, Volume 39, September 2021
Bennett H.Q., Kingston A., Lourida I., Robinson L., Corner L., Brayne C.E. et al.
Background:: Disability-free life expectancy (DFLE) inequalities by socioeconomic deprivation are widening, alongside rising prevalence of multiple long-term conditions (MLTCs). We use longitudinal data to assess whether MLTCs contribute to the widening DFLE inequalities by socioeconomic deprivation. Methods:: The Cognitive Function and Ageing Studies (CFAS I and II) are large population-based studies of those ≥65 years, conducted in three areas in England. Baseline occurred in 1991 (CFAS I, n=7635) and 2011 (CFAS II, n=7762) with two-year follow-up. We defined disability as difficulty in activities of daily living, MLTCs as the presence of at least two of nine health conditions, and socioeconomic deprivation by area-level deprivation tertiles. DFLE and transitions between disability states and death were estimated from multistate models. Findings:: For people with MLTCs, inequalities in DFLE at age 65 between the most and least affluent widened to around 2.5 years (men:2.4 years, 95% confidence interval (95%CI) 0.4–4.4; women:2.6 years, 95%CI 0.7–4.5) by 2011. Incident disability reduced for the most affluent women (Relative Risk Ratio (RRR):0.6, 95%CI 0.4–0.9), and mortality with disability reduced for least affluent men (RRR:0.6, 95%CI 0.5–0.8). MLTCs prevalence increased only for least affluent men (1991: 58.8%, 2011: 66.9%) and women (1991: 60.9%, 2011: 69.1%). However, DFLE inequalities were as large in people without MLTCs (men:2.4 years, 95%CI 0.3–4.5; women:3.1 years, 95% CI 0.8–5.4). Interpretation:: Widening DFLE inequalities were not solely due to MLTCs. Reduced disability incidence with MLTCs is possible but was only achieved in the most affluent.