Study Highlights Differences In Brain Changes Between Black And White Americans With Alzheimer’s

Researchers in the US have found that there may be differences in the changes that take place in the brains of African Americans and European Americans with a diagnosis of Alzheimer’s disease.

Alzheimer’s is one of a number of diseases that can cause dementia. Currently the only way to confirm a specific diagnosis of Alzheimer’s disease is with a post-mortem, which will reveal characteristic protein plaques and tangles inside the brain. Some people with dementia will have more than one disease underlying their condition. This is known as mixed dementia and is usually Alzheimer’s plaques and tangles in the presence of other changes to the brain that cause conditions like vascular dementia or dementia with Lewy bodies.

In this study researchers examined brain tissue from 122 people who died with a clinical diagnosis of Alzheimer’s and donated their brains to research. Of those studied, 41 were African Americans and 81 were European Americans who were matched based on age, sex, years of education and their memory and thinking ability before death. The researchers found that in the brains of most of those studied, Alzheimer’s changes appeared alongside those of at least one other disease that causes dementia. While 51% of European Americans had these signs of multiple diseases, the figure was even higher for African Americans, at 71%. The additional changes more common in the brains of African Americans were those associated with dementia with Lewy bodies, as well as areas of blood vessel damage known as infarcts.

Dr Simon Ridley, Head of Research at of Alzheimer’s Research UK, said:

“While mixed dementia can be difficult to identify in the clinic, an accurate diagnosis is vital if people with dementia are to be offered the most appropriate treatment, care and support. As well as highlighting the extent of mixed dementia in general, this research seems to suggest that African Americans are even more likely to have signs of multiple diseases underlying an Alzheimer’s diagnosis than white Americans. This was a fairly small study and there are a number of possible factors that could contribute to these findings. Without more research we can’t know if these differences could also apply to ethnic groups in the UK.

“We know dementia can affect anyone regardless of background or ethnicity, and while the risk factors are complex, research suggests there are things we all can be doing to help reduce the risk of developing the condition. Eating healthily, drinking in moderation, not smoking, keeping blood pressure and cholesterol in check, and staying mentally and physically active can all help to maintain a healthy brain as we get older.”