Affiliations: Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
Correspondence:
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Correspondence to: Paul T. Williams, Life Sciences Division, Lawrence Berkeley National Laboratory, Donner 464, 1 Cyclotron Road, Berkeley, CA 94720, USA. Tel.: +1 510 486 5633; Fax: +1 510 486 5990; E-mail: [email protected].
Abstract: Background:Whether lifestyle affects Alzheimer's disease (AD) risk remains controversial. Objective:Test whether exercise, diet, or statins affect AD mortality in 153,536 participants of the National Runners' and Walkers' Health Studies. Methods: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. Results: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). Conclusion:Exercise, statin, and fruit intake were associated with lower risk for AD mortality.
