Lower risk of Alzheimer's disease mortality with exercise, statin, and fruit intake

Whether lifestyle affects Alzheimer's disease (AD) risk remains controversial.

Test whether exercise, diet, or statins affect AD mortality in 153,536 participants of the National Runners' and Walkers' Health Studies.

Hazard ratios (HR) and 95% confidence intervals (95% CI) were obtained from Cox proportional hazard analyses for AD mortality versus baseline metabolic equivalent (MET) hours/d of exercise energy expenditure (1 MET equals approximately 1 km run), statin use, and fruit intake when adjusted for age, race, gender, education, and exercise mode.

The National Death Index identified 175 subjects who died with AD listed as an underlying (n = 116) or contributing (n = 59) cause of death during 11.6-year average mortality surveillance. Relative to exercising <1.07 MET-hours/d, AD mortality was 6.0% lower for 1.07 to 1.8 MET-hours/d (HR: 0.94, 95% CI: 0.59 to 1.46, p = 0.79), 24.8% lower for 1.8 to 3.6 MET-hours/d (HR: 0.75, 95% CI: 0.50 to 1.13, p = 0.17), and 40.1% lower for ≥3.6 MET-hours/d (HR: 0.60, 95% CI: 0.37 to 0.97, p = 0.04). Relative to non-use, statin use was associated with 61% lower AD mortality (HR: 0.39, 95% CI: 0.15 to 0.82, p = 0.01), whereas use of other cholesterol-lowering medications was not (HR: 0.78, 95% CI: 0.40 to 1.38, p = 0.42). Relative to <1 piece of fruit/day, consuming 2 to 3 pieces daily was associated with 39.7% lower AD mortality (HR: 0.60, 95% CI: 0.39 to 0.91, p = 0.02) and ≥3 pieces/day with 60.7% lower AD mortality (HR: 0.39, 95% CI: 0.22 to 0.67, p = 0.0004).

Exercise, statin, and fruit intake were associated with lower risk for AD mortality.