J Natl Med Assoc
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Empirical observations suggest a preponderance of cases of sporadic Alzheimer's disease among whites relative to blacks. If true, this might indicate a genetic basis for non-familial Alzheimer's disease. Among 6,000 consecutive autopsies performed at The Johns Hopkins Hospital, 242 adults with dementia were identified. ⋯ Among the remaining 144 cases, the proportions of whites and blacks were similar, yet the frequency of Alzheimer's disease was 2.6 times higher among whites (P = 0.001), dementia due to Parkinson's disease was more frequent among whites (P = 0.05), and the frequencies of multi-infarct dementia and dementia due to chronic ethanol abuse were higher among blacks (P = 0.004 and P = 0.007, respectively). Moreover, in brains from neurologically intact controls, incidental histologic lesions of Alzheimer's disease were observed more frequently in whites than blacks (P = 0.01). These findings provide a strong argument in favor of genetic transmission of sporadic Alzheimer's disease.