Stressful experiences equivalent to 'more than 4 years cognitive ageing'
Researchers at the Alzheimer's Association International Conference 2017 in London have highlighted the impact stressful life events can have on brain function.
The study is one of a range of US studies highlighting racial disparities in dementia, with African Americans exhibiting higher rates of dementia than Latinos, Whites and Asian Americans. Studies presented at the conference explored factors that could contribute to these difference in risk, highlighting place of birth, early life conditions, stressful events and living in disadvantaged neighbourhoods among possible contributing factors.
A team from Wisconsin in the US focused on the impact of stressful events on brain health. They collected data from 1,320 people with an average age of 58, who provided information about their lifetime stressful experiences and took part in tests of memory and thinking. They found that experiencing more stressful events was associated with a worse performance in memory and thinking tests and that this effect was most apparent in African Americans. Each reported experience appeared to equate to around four years of cognitive ageing, with African Americans reporting more stressful experiences in their lifetime.
Dr Carol Routledge, Director of Research at Alzheimer's Research UK, said:
"Our brains are incredibly intricate organs that show enormous resilience to keep us ticking every day. Stressful life events can turn our lives upside down for a time and though most people can eventually return to an even keel, we can't be sure how psychological stress could impact the workings of the brain over time. This study showed a link between lifetime stress and worse performance on memory and thinking tests, but there could be a number of different factors underlying this relationship and the long-term impact wasn't explored. However, there is a growing realisation that events and experiences throughout life can impact the brain decades later and researchers must take a whole life-span approach to understanding brain health in later life."
"Previous US research has pointed to differences in rates of dementia between different ethnic groups. While this study didn't look at whether people went on to develop dementia, the researchers found that African Americans experienced a disproportionately high number of stressful life events, which could contribute to racial differences in later life cognition. It's less clear whether a similar pattern of racial difference exists in the UK, and further investment in research is the only way to build a clearer picture. Alzheimer's Research UK is working with government and other charities to build the evidence base around the impact of dementia in Black, Asian and minority ethnic communities to take steps towards reducing health inequalities across society. Understanding differences in risk and awareness of dementia among different ethnic groups in the UK is vitally important, to ensure tailored information and support can be provided to everyone affected by the condition."