Background: The WHO defines 'healthy ageing' as 'the process of developing and maintaining the functional ability'. Late-life depression and frailty compromise well-being and independence of older people. To date, there exists little research on the interaction of the dynamic processes of frailty and depression and only a few studies were longitudinal. Conclusions about the direction of effects remained uncertain. Methods: Data were obtained from each of the last six biyearly waves (2007-2017) of the Longitudinal Urban Cohort Ageing Study (LUCAS) in Hamburg, Germany, a prospective observational cohort study of manifold aspects of ageing. Screening of predictor and event variables: depressed mood: one question from the 5-item Mental Health Inventory Screening Test; frailty: LUCAS Functional Ability Index, status 'frail'; disability: one question on need for human help with basic activities of daily living. Kaplan-Meier curves and Cox's proportional hazards regression were used for time-to-event analyses with shifting baseline. Results: Sample size in 2007 was 2012, average age 76.2 years; ±6.5. Main results were as follows: (1) depression significantly increased the hazard of subsequent frailty (HR=1.581; 95% CI 1.257 to 1.988; p<0.001); (2) frailty significantly increased the hazard of subsequent depression (HR=2.324; 95% CI 1.703 to 3.172; p<0.001); (3) depression significantly increased the hazard of subsequent disability (HR=2.589; 95% CI 1.885 to 3.557; p<0.001) and (4) disability did not significantly increase the hazard of subsequent depression (HR=1.540; 95% CI 0.917 to 2.579; p=0.102). Conclusion: Our results suggest an interdependence of the processes of depression and frailty/disability rather than unidirectional dependencies. These observable processes may be representative of underlying unobservable profound life changes. Obviously, there is a need for early screening to initiate appropriate interventions.

ageing, depression, Functioning and disability, geriatrics, longitudinal studies
dx.doi.org/10.1136/jech-2020-214168, hdl.handle.net/1765/134724
MINDMAP
Journal of Epidemiology and Community Health
This work was funded by the European Commission 7th Framework Programme; grant id h2020/ 667661 - PROMOTING MENTAL WELLBEING IN THE AGEING URBAN POPULATION: DETERMINANTS, POLICIES AND INTERVENTIONS IN EUROPEAN CITIES (MINDMAP)
Department of Public Health

Dapp, U, Minder, C.E, Golgert, G, Klugmann, B, Neumann, L, & von Renteln-Kruse, W. (2020). The inter-relationship between depressed mood, functional decline and disability over a 10-year observational period within the Longitudinal Urban Cohort Ageing Study (LUCAS). Journal of Epidemiology and Community Health. doi:10.1136/jech-2020-214168