Characterization of risk factors for vascular dementia - The Honolulu-AsiaAging Study

Background: The Honolulu Heart Program (HHP) is a prospective study of hear t 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 examinat ion of the cohort identified all patients with vascular dementia (VaD) usin g the criteria of the California Alzheimer's Disease Diagnostic and Treatme nt Center. Objective: To characterize patients with VaD by stroke subtype a nd 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: Si xty-eight men with VaD were compared with 3,335 men without dementia or str oke (NSND). Men with VaD were also compared with 106 men with stroke who we re not demented (SND). Candidate risk factors were measured prospectively. Results: Of the 68 men with VaD there were 34 (50%) whose VaD was attribute d 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 remai nder could not be classified. In a multivariate logistic regression model f or VaD compared with NSND containing variables found to be associated with VaD in a univariate analysis, age (odds ratio [OR] 1.19, 95% confidence int erval [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) remain ed 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 u se of supplementary vitamin E (OR 0.32, 95% CI 0.12 to 0.82) were protectiv e. 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 fo r 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. Ag e and traditional vascular risk factors are important contributors to the d evelopment of VaD in late life. The antioxidant vitamin E and presently unk nown factors related to a Western diet as opposed to an Oriental diet may b e protective against developing VaD.