LaMonte MJ, Buchner DM, Rillamas-Sun E, Di C, Evenson KR, Bellettiere J, Lewis CE, Lee IM, Tinker LF, Seguin R, Zaslovsky O, Eaton CB, Stefanick ML, LaCroix AZ.
prospectively examine associations between accelerometer-measured
physical activity (PA) and mortality in older women, with an emphasis on
Prospective cohort study with baseline data collection between March 2012 and April 2014.
Women's Health Initiative cohort in the United States.
Community-dwelling women aged 63 to 99 (N = 6,382).
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
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
< .001, for high light; and, 1.00, 0.63 (0.50, 0.79), 0.42 (0.30,
0.57) trend P < .001, for moderate-to-vigorous PA (MVPA).
Associations remained significant for high light-intensity PA and MVPA
(P < .001) after further adjustment for physical function. Each
30-min/d increment in light-intensity (low and high combined) PA and
MVPA was associated, on average, with multivariable relative risk
reductions of 12% and 39%, respectively (P < .01). After further
simultaneous adjusting for light intensity and MVPA, the inverse
associations remained significant (light-intensity PA: RR = 0.93, 95% CI
= 0.89-0.97; MVPA: RR = 0.67, 95% CI = 0.58-0.78). These relative risks
did not differ between subgroups for age or race and ethnicity
(interaction, P ≥ .14, all).
measured using accelerometers, light-intensity and MVPA are associated
with lower mortality in older women. These findings suggest that
replacing sedentary time with light-intensity PA is a public health
strategy that could benefit an aging society and warrants further