Accelerometer-Measured Physical Activity and Mortality in Women Aged 63 to 99

Abstract

Objectives: To prospectively examine associations between accelerometer-measured physical activity (PA) and mortality in older women, with an emphasis on light-intensity PA. Design: Prospective cohort study with baseline data collection between March 2012 and April 2014. Setting: Women's Health Initiative cohort in the United States. Participants: Community-dwelling women aged 63 to 99 (N = 6,382). Measurements: Minutes per day of usual PA measured using hip-worn triaxial accelerometers, physical functioning measured using the Short Physical Performance Battery, mortality follow-up for a mean 3.1 years through September 2016 (450 deaths). Results: When adjusted for accelerometer wear time, age, race-ethnicity, education, smoking, alcohol, self-rated health, and comorbidities, relative risks (95% confidence intervals) for all-cause mortality across PA tertiles were 1.00 (referent), 0.86 (0.69, 1.08), 0.80 (0.62, 1.03) trend P =.07, for low light; 1.00, 0.57 (0.45, 0.71), 0.47 (0.35, 0.61) trend P