Objectively measured physical activity, sedentary behaviour and all-cause mortality in older men: does volume of activity matter more than pattern of accumulation?

摘要

Objectives To understand how device-measured sedentary behaviour and physical activity are related to all-cause mortality in older men, an age group with high levels of inactivity and sedentary behaviour. Methods Prospective population-based cohort study of men recruited from 24 UK General Practices in 1978-1980. In 2010-2012, 3137 surviving men were invited to a follow-up, 1655 (aged 71-92 years) agreed. Nurses measured height and weight, men completed health and demographic questionnaires and wore an ActiGraph GT3x accelerometer. All-cause mortality was collected through National Health Service central registers up to 1 June 2016. Results After median 5.0 years' follow-up, 194 deaths occurred in 1181 men without pre-existing cardiovascular disease. For each additional 30min in sedentary behaviour, or light physical activity (LIPA), or 10min in moderate to vigorous physical activity (MVPA), HRs for mortality were 1.17 (95% Cl 1.10 to 1.25), 0.83 (95% Cl 0.77 to 0.90) and 0.90 (95% Cl 0.84 to 0.96), respectively. Adjustments for confounders did not meaningfully change estimates. Only LIPA remained significant on mutual adjustment for all intensities. The HR for accumulating 150 min MVPA/week in sporadic minutes (achieved by 66% of men) was 0.59 (95% Cl 0.43 to 0.81) and 0.58 (95% Cl 0.33 to 1.00) for accumulating 150 min MVPA/week in bouts lasting >10min (achieved by 16% of men). Sedentary breaks were not associated with mortality. Conclusions In older men, all activities (of light intensity upwards) were beneficial and accumulation of activity in bouts >10 min did not appear important beyond total volume of activity. Findings can inform physical activity guidelines for older adults.