Physical activity and trajectories of frailty among older adults: Evidence from the English Longitudinal Study of Ageing.
BACKGROUND
Frail older adults are heavy users of health and social care. In order to reduce the costs associated with frailty in older age groups, safe and cost-effective strategies are required that will reduce the incidence and severity of frailty.


OBJECTIVE
We investigated whether self-reported intensity of physical activity (sedentary, mild, moderate or vigorous) performed at least once a week can significantly reduce trajectories of frailty in older adults who are classified as non-frail at baseline (Rockwood's Frailty Index [FI] ≤ 0.25).


METHODS
Multi-level growth curve modelling was used to assess trajectories of frailty in 8649 non-frail adults aged 50 and over and according to baseline self-reported intensity of physical activity. Frailty was measured in five-year age cohorts based on age at baseline (50-54; 55-59; 60-64; 65-69; 70-74; 75-79; 80+) on up to 6 occasions, providing an average of 10 years of follow-up. All models were adjusted for baseline sex, education, wealth, cohabitation, smoking, and alcohol consumption.


RESULTS
Compared with the sedentary reference group, mild physical activity was insufficient to significantly slow the progression of frailty, moderate physical activity reduced the progression of frailty in some age groups (particularly ages 65 and above) and vigorous activity significantly reduced the trajectory of frailty progression in all older adults.


CONCLUSIONS
Healthy non-frail older adults require higher intensities of physical activity for continued improvement in frailty trajectories.
Department of Epidemiology & Public Health, University College London, London, United Kingdom.
Nina T
http://orcid.org/0000-0003-1857-2122
NT
Rogers
Department of Geography and Sustainable Development, Irvine Building, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom.
Alan
A
Marshall
Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom.
Chrissy H
CH
Roberts
Department of Epidemiology & Public Health, University College London, London, United Kingdom.
Panayotes
P
Demakakos
Department of Epidemiology & Public Health, University College London, London, United Kingdom.
Andrew
A
Steptoe
Department of Epidemiology & Public Health, University College London, London, United Kingdom.
Shaun
S
Scholes
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015331:Cohort Studies; D004739:England; D015444:Exercise; D005260:Female; D016330:Frail Elderly / Q000706:statistics & numerical data; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged