There may be no notable difference in the risk of death from Alzheimer's and other forms of dementia between white and African American adults, according to a study published on Monday.
The study, which appears in the June edition of the Archives of Neurology, contradicts previously held views that Alzheimer's strikes older African Americans more acutely than it does Caucasians in the United States.
Overall, researchers said their results "do not suggest strong racial differences in survival for persons with mild cognitive impairment and Alzheimer's disease."
Doctors at the Rush University Medical Center in Chicago led by Robert Wilson studied 1,715 older adults from four Chicago neighborhoods. Their average age was 80.1 and just over half, 52.5 percent, were African American.
Each participant had a health evaluation; was given thinking, learning, functioning and memory tests; and their health history was reviewed.
Based on the tests, 296 or 17.3 percent of the participants were diagnosed with Alzheimer's disease, 597 or 34.8 percent with mild cognitive impairment, and 20 or 1.2 percent with other forms of dementia.
The remainder - 802, or 46.8 percent of the test group - had no cognitive impairment.
During a follow-up period of up to 10 years 634 people or 37 percent of the test participants died.
Those who died included 25.8 percent of those without cognitive impairment, 40.4 percent of those with mild cognitive impairment, 59.1 percent of those with Alzheimer's, and 60 percent of those with other forms of dementia.
"Compared with people without cognitive impairment, risk of death was increased by about 50 percent among those with mild cognitive impairment and was nearly three-fold greater among those with Alzheimer's disease," the authors said.
"These effects were seen among African Americans and whites and did not differ by race."