In four different studies presented at the Alzheimer's Association's annual conference in London on Sunday, July 16, researchers found that the conditions that have disproportionate impact on blacks such as poor living conditions and potentially disruptive events, which include divorce of parents, chronic unemployment, and loss of sibling, may have severe effect on their brain health later in life.
The studies showed that the number of people with Alzheimer's and other dementias differed between races and also suggested that stress in early life and neighborhood disadvantage contribute to increased dementia risk.
"We've always known [stress] is not good for your brain, but now we are seeing that stressful situations even early in life are critical in addressing brain health". The group who experienced problems with their hearing were more likely to score significantly lower on cognitive tests and were roughly three times as likely to be assessed as having mild cognitive impairment.
A separate study by the Kaiser Permanente and the University of California at San Francisco found a higher degree of dementia risk for people born in states with high infant mortality rates.
When combined with just one hour a week of social interaction, it improved patients' quality of life and eased their agitation, the researchers said. In recent years, however, researchers also looked at social factors that may increase the risk. "Our findings suggest that differences in early life conditions may contribute to racial inequalities in dementia rate, and they point to growing evidence that early life conditions contribute to dementia risk in late life".
"However, the findings do indicate that more should be done to support people from disadvantaged communities that are more likely to experience stressful life events." he said. This is because they scored poorer results in the memory tests than other groups and also tended to live in poorer neighbourhoods.
"This linkage between neighborhood disadvantage and Alzheimer's has never been explored until our work", said Amy J. Kind, a physician and researcher at the University of Wisconsin.
The subjects' average age was 58 and included 1,232 white Americans and 82 African Americans. For the past year or so, she focused on how that would intersect with race.
Researchers from Wisconsin University in the United States also found that African American experienced 60 per cent more stressful events than white people during their lifetimes.