Background: The Honolulu Heart Program (HHP) is a prospective study of heart disease and stroke that has accumulated risk factor data on a cohort of 8,006 Japanese American men since the study began in 1965. A recent examination of the cohort identified all patients with vascular dementia (VaD) using the criteria of the California Alzheimer's Disease Diagnostic and Treatment Center.
Objective: To characterize patients with VaD by stroke subtype and to investigate risk factors for VaD in a cohort of Japanese American men, aged 71 to 93, living in Hawaii and participating in the HHP.
Methods: Sixty-eight men with VaD were compared with 3,335 men without dementia or stroke (NSND). Men with VaD were also compared with 106 men with stroke who were not demented (SND). Candidate risk factors were measured prospectively.
Results: Of the 68 men with VaD there were 34 (50%) whose VaD was attributed to small vessel infarcts, 16 (23%) whose VaD was related to large vessel infarcts, and 11 (16%) with both large and small vessel infarcts. The remainder could not be classified. In a multivariate logistic regression model for VaD compared with NSND containing variables found to be associated with VaD in a univariate analysis, age (odds ratio [OR] 1.19, 95% confidence interval [CI] 1.13 to 1.27), coronary heart disease (OR 2.50, 95% CI 1.35 to 4.62), and 1-hour postprandial glucose (OR 1.41, 95% CI 1.06 to 1.88) remained significantly predictive of VaD, whereas preference for a Western diet (OR 0.54, 95% CI 0.30 to 0.98) as opposed to an Oriental or mixed diet and use of supplementary vitamin E (OR 0.32, 95% CI 0.12 to 0.82) were protective. A similar model for the comparison of men with VaD and SND revealed age (OR 1.24, 95% CI 1.14 to 1.35) was predictive of VaD, whereas preference for a Western diet (OR 0.43, 95% CI 0.22 to 0.86) was protective.
Conclusions: The most common stroke subtype associated with VaD was lacunar stroke. Age and traditional vascular risk factors are important contributors to the development of VaD in late life. The antioxidant vitamin E and presently unknown factors related to a Western diet as opposed to an Oriental diet may be protective against developing VaD.