We did not find evidence to support the hypothesis that multilingualism is associated with cognitive reserve.

Background The cognitive reserve hypothesis would predict that use of written Japanese should confer protection against dementia because of the complexity of its ideograms compared with written English. We sought to test this hypothesis in analyses from a longitudinal study of Japanese-American men. Methods Participants were second-generation Japanese-American men (Nisei) on the island of Oahu, Hawaii, who were seen in 1965 and in subsequent examinations to detect dementia beginning in 1991-1993. Use of spoken and written Japanese was self-reported in 1965 (Analyses 1 and 2), and mid-life use of written Japanese and written English was self-reported in 1994-1996 (Analysis 3). We analyzed prevalent dementia outcomes in 1991-1993 (Analysis 1, n=3,139) using logistic regression, and incident dementia outcomes in 1994-2002 (Analysis 2, n=2,299) and in 1997-2002 (Analysis 3, n=1,655) using Cox proportional hazards regression. Dementia outcomes included all-cause dementia, probable and possible Alzheimer disease, and probable vascular dementia. We adjusted models for probable and possible confounders. Results Participants who reported proficiency with written Japanese were older and had lower incomes. For Analysis 1, there were 154 prevalent cases of dementia, 74 of Alzheimer disease, and 43 of vascular dementia; for Analysis 2, 236 incident cases of dementia, 138 of Alzheimer disease, and 45 of vascular dementia; and for Analysis 3, 125 incident cases of dementia, 80 of Alzheimer disease, and 20 of vascular dementia. There was no relationship in adjusted models between self-reported proficiency with written Japanese and any dementia outcomes. Conclusions Proficiency with written Japanese does not appear to be protective for dementia.

In this preliminary case series, we describe patients with "susceptibility etching" on SWI who were also found to have profound coagulation impairment. While other comorbities may also contribute to this novel sign, we suggest that a possible etiology may be secondary to microvascular in situ formation of fine thrombi and/or emboli lodged into an area of vascular caliber reduction and maybe related to thrombotic microangiopathy.

BackgroundCross-cultural studies of Alzheimer disease (AD) in genetically similar populations have been designed to detect possible environmental risk factors. It may be possible to perform similar analyses on a single population by examining acculturation, which is the extent to which individuals moving into a host society adapt to changes in lifestyle. Our objective was to determine whether acculturation to Western society was a risk factor for developing AD in an elderly population of Japanese-Americans.Study Design and MethodsA cohort of 1,622 dementia-free individuals with baseline acculturation scores was followed for 8 years with biennial cognitive screening assessments using the Cognitive Abilities Screening Instrument. Individuals scoring < 88 were given a full physical and neuropsychological evaluation. Diagnoses of dementia and AD were obtained by consensus agreement using criteria from the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. Item response theory was used to combine 20 questionnaire responses to generate acculturation scores. Scores were divided into quartiles for analysis. Hazard ratios were calculated using the Cox proportional hazards model to determine the risk of AD for participants in high quartiles of acculturation versus those in low quartiles. We adjusted models for cardiovascular disease risk factors and demographic characteristics such as primary language and income.ResultsIn unadjusted models, the relative hazard associated with higher levels of acculturation was 0.6 (95% CI 0.4-0.97). With adjustments for demographic characteristics, the relative hazard associated with higher levels of acculturation was 1.84 (95% CI 0.5-6.6). With further adjustments for vascular disease risk factors and apolipoprotein E genotype, the relative hazard associated with higher levels of acculturation was 1.83 (95% CI 0.4-8.5).ConclusionJapanese-Americans in the highest acculturation group appear to have an increased risk for acquiring AD, though the confidence interval includes the null value. This finding suggests further research to determine a biological rationale.