Abstract
BACKGROUND: The influence of physical activity (PA) and sedentary behavior (SB) on survival to late age with intact mobility is unclear. This study investigated associations between accelerometer-measured daily PA, SB, and survival to age 90 birthyear with and without intact mobility in the Women's Health Accelerometry Collaboration (WHAC). METHODS: Postmenopausal US women aged 78-89 years without mobility disability were followed for an average of 6.1 years. At age 90 birthyear, participants were categorized as: (1) surviving with intact mobility, (2) surviving with mobility disability, or (3) deceased. Participants wore an accelerometer on the hip for up to 7 days at baseline from 2011 to 2015. Covariate-adjusted multinomial logistic regression models estimated odds ratios (ORs) of PA (light, moderate-to-vigorous [MVPA], total, steps) and SB (sitting time, mean sitting bout duration) with survival outcomes relative to dying. RESULTS: Among 2656 women (mean baseline age 83.1 years), 62.8% survived with intact mobility, 22.3% with mobility disability, and 15.0% died. Compared to dying before age 90, the OR (95% confidence intervals [CI]) for every 1-SD increment in accelerometer variables and survival with intact mobility were 1.36 (1.20, 1.54) for light PA, 1.69 (1.47, 1.96) for MVPA, 1.51 (1.33, 1.71) for total PA, 1.75 (1.51, 2.03) for steps, 0.70 (0.61, 0.80) for sitting time, and 0.79 (0.70, 0.89) for sitting bouts. Similar, weaker trends were present for mobility disability. CONCLUSIONS: These findings corroborate the potential role of increasing physical activity in preserving physical functioning as an important element of healthy longevity.