Causal effects of physical activity and sedentary behaviour on health deficits accumulation in older adults.

摘要: Background Increasing physical activity (PA) and reducing sedentary behaviour (SB) have been associated with healthy ageing, but their effects when adjusted for reverse causation selection bias remain unclear. Methods A deficits accumulation (DA) index based on the number severity of 51 health (0-100%) was calculated at baseline three biannual follow-up visits, in a representative cohort 3 228 community-dwelling older adults Spain. Average differences DA by previous recreational PA, household mentally-active SB passive were estimated using marginal structural models inverse probability exposure censoring weights. Results Compared participants PA 10-19.9 metabolic equivalent hours/week (MET-hours/week), average (95% confidence intervals) 0.19 (-1.09, 1.48), 0.69 (-0.23, 1.61), -0.66 (-1.34, 0.02), -0.87 (-1.59, -0.13) -0.55 (-1.37, 0.28) 0, 0.1-9.9, 20-29.9, 30-39.9 ≥40 MET-hours/week, respectively (P trend = 0.006). Household showed no effect subsequent after adjusting causation. Women, not men, who spent 7-14.9, 15-20.9 ≥21 h/week mentally active had decreases 0.09 (-1.00, 1.19), 1.08 (-0.28, 2.45) 2.17 (0.58, 3.75), respectively, compared 1-6.9 0.005); whereas women 3-3.9, 4-4.9 ≥5 h/day increases 0.41 (-0.52, 1.35), 1.35 (0.13, 2.57) 2.13 (0.78, 3.47), 2-2.9 0.001). Conclusions The proposed methodology allows estimation causal simulating random assignment which all subjects same exposure.