Alzheimer’s disease may cause different changes in the brain in African-Americans than in white Americans of European descent, according to a study published today (July 15) in the medical journal of the American Academy of Neurology.
The study included 41 African-Americans with a clinical diagnosis of Alzheimer’s disease who had an autopsy of their brain performed after death. They were then compared to 81 deceased European-Americans who had Alzheimer’s disease with the same level of disease severity and were of the same age, sex and education level.
Researchers looked for typical signs of Alzheimer’s disease (plaques and tangles) as well as other brain changes that can cause dementia, such as infarcts (the brain changes associated with stroke) and Lewy bodies (associated with Lewy body or Parkinson’s disease).
Only about half of the European-Americans had pure Alzheimer’s disease pathology whereas the rest also had infarcts and/or Lewy bodies.
In contrast, less than 25 percent of the African Americans had pure Alzheimer’s disease pathology. African-Americans also had more frequent and severe blood vessel disease.
Dr Doug Brown, Director of Research at Alzheimer’s Society, said:
‘There are 850,000 people with dementia in the UK and the majority of them have Alzheimer’s disease. This new study shows that most people with Alzheimer’s disease also have signs of other forms of dementia, and this is more common in black people than white. Through research we are learning more about the complexities of what happens in the brain and this finding reinforces that we cannot view Alzheimer’s disease in isolation – all forms of dementia desperately need new treatments.
‘This study also demonstrates the need to get as many people from all ethnic backgrounds involved in research. To make this possible, Alzheimer’s Society has helped to launch Join Dementia Research, an online service to make taking part in research easier, which has already signed up over 8000 volunteers around the country.’