Healthy behaviours at age 50 years and frailty at older ages in a 20-year follow-up of the UK Whitehall II cohort

Frailty is associated with increased risk of various health conditions, disability, and death. Health behaviours are thought to be a potential target for frailty prevention, but the evidence from previous studies is based on older populations with short follow-ups, making results susceptible to reverse causation bias. A research team examined the associations of healthy behaviours at age 50, singly and in combination, as well as 10-year change in the number of healthy behaviours over midlife with future risk of frailty.
In the prospective cohort study of 6,357 (29.2% women; 91.7% white) participants from the British Whitehall II cohort, healthy behaviours—non-smoking, moderate alcohol consumption, ≥2.5 hours per week of moderate to vigorous physical activity, and consumption of fruits or vegetables at least twice a day—were measured at age 50, and change in behaviours was measured between 1985 (mean age = 44.4) and 1997 (mean age = 54.8). Frailty was assessed in clinical examinations in 2002, 2007, 2012, and 2015. Participants were classified as frail if they had ≥3 of the following criteria: slow walking speed, low grip strength, weight loss, exhaustion, and low physical activity.
Over an average follow-up of 20.4 years (standard deviation, 5.9), 445 participants developed frailty. Each healthy behaviour at age 50 was associated with lower risk of incident frailty: hazard ratio (HR) after adjustment for other health behaviours and baseline characteristics 0.56 in non-smokers, 0.73 for moderate alcohol consumption, 0.66 for ≥2.5 hours of physical activity per week, and 0.76 for consumption of fruits or vegetables at least twice a day. A greater number of healthy behaviours was associated with reduced risk of frailty, with the HR for each additional healthy behaviour being 0.69 and the HR for having all versus no healthy behaviours at age 50 being 0.28. Among participants with no or 1 healthy behaviour in 1985, those who increased the number of healthy behaviours by 1997 were at a lower risk of frailty (mean follow-up = 16 years) compared with those with no such increase: the HR was 0.64 for change to 2 healthy behaviours and 0.57 for change to 3–4 healthy behaviours in 1997.
The study findings suggest that healthy behaviours at age 50, including moderate drinking, as well as improvements in behaviours over midlife, are associated with a lower risk of frailty later in life. Their benefit accumulates so that risk of frailty decreases with greater number of healthy behaviours, suggesting that healthy behaviours in midlife are a good target for frailty prevention.
Source: Gil-Salcedo A, Dugravot A, Fayosse A, Dumurgier J, Bouillon K, Schnitzler A, et al. (2020) Healthy behaviors at age 50 years and frailty at older ages in a 20-year follow-up of the UK Whitehall II cohort: A longitudinal study. PLoS Med 17(7): e1003147.