Lifestyle and the risk of dementia in Japanese-american men.
OBJECTIVE
To determine whether adhering to a healthy lifestyle in midlife may reduce the risk of dementia.


METHODS
Case-control study nested in a prospective cohort.


METHODS
The Honolulu-Asia Aging Study, Oahu, Hawaii.


METHODS
Three thousand four hundred sixty-eight Japanese-American men (mean age 52 in 1965-1968) examined for dementia 25 years later.


METHODS
Men at low risk were defined as those with the following midlife characteristics: nonsmoking, body mass index (BMI) less than 25.0 kg/m(2) , physically active, and having a healthy diet (based on alcohol, dairy, meat, fish, fruits, vegetables, cereals, and ratio of monounsaturated to saturated fat). Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for developing overall dementia, Alzheimer's disease (AD), and vascular dementia (VaD), adjusting for potential confounders.


RESULTS
Dementia was diagnosed in 6.4% of men (52.5% with AD, 35.0% with VaD). Examining the risk factors individually, BMI was most strongly associated with greater risk of overall dementia (OR = 1.87, 95% CI = 1.26-2.77; BMI > 25.0 vs <22.6 kg/m(2) ). All of the individual risk factors except diet score were significantly associated with VaD, whereas none were significantly associated with AD alone. Men with all four low-risk characteristics (7.2% of the cohort) had the lowest OR for overall dementia (OR = 0.36, 95% CI = 0.15-0.84). There were no significant associations between the combined low-risk characteristics and the risk of AD alone.


CONCLUSIONS
Among Japanese-American men, having a healthy lifestyle in midlife is associated with a lower risk of dementia in late life.
Honolulu-Asia Aging Study, Kuakini Medical Center; Veterans Affairs Pacific Islands Healthcare System, Honolulu, Hawaii. rpgelber@gmail.com
Rebecca P
RP
Gelber
Helen
H
Petrovitch
Kamal H
KH
Masaki
Robert D
RD
Abbott
George Webster
GW
Ross
Lenore J
LJ
Launer
Lon R
LR
White
D000368:Aged; D000369:Aged, 80 and over; D001213:Asian; D001294:Attitude to Health / Q000208:ethnology*; D003704:Dementia / Q000208:ethnology* / Q000209:etiology; D006801:Humans; D008019:Life Style / Q000208:ethnology*; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D014481:United States / Q000453:epidemiology