Lifestyle-related factors in late midlife as predictors of frailty from late midlife into old age: a longitudinal birth cohort study

Background Few studies have examined longitudinal changes in lifestyle-related factors and frailty.Methods We examined the association between individual lifestyle factors (exercise, diet, sleep, alcohol, smoking and body composition), their sum at baseline, their change over the 17-year follow-up and the rate of change in frailty index values using linear mixed models in a cohort of 2,000 participants aged 57-69 years at baseline.Results A higher number of healthy lifestyle-related factors at baseline was associated with lower levels of frailty but not with its rate of change from late midlife into old age. Participants who stopped exercising regularly (adjusted beta x Time = 0.19, 95%CI = 0.10, 0.27) and who began experiencing sleeping difficulties (adjusted beta x Time = 0.20, 95%CI = 0.10, 0.31) experienced more rapid increases in frailty from late midlife into old age. Conversely, those whose sleep improved (adjusted beta x Time = -0.10, 95%CI = -0.23, -0.01) showed a slower increase in frailty from late midlife onwards. Participants letting go of lifestyle-related factors (decline by 3+ factors vs. no change) became more frail faster from late midlife into old age (adjusted beta x Time = 0.16, 95% CI = 0.01, 0.30).Conclusions Lifestyle-related differences in frailty were already evident in late midlife and persisted into old age. Adopting one new healthy lifestyle-related factor had a small impact on a slightly less steeply increasing level of frailty. Maintaining regular exercise and sleeping habits may help prevent more rapid increases in frailty.