Researchers at the University of Edinburgh in the U.K. studied seven vascular risk factors and brain structures of 9,772 people and were able to connect all but one risk factor to more brain shrinkage. They found no difference in brain size or structure related to high cholesterol levels.
Their findings, published in the European Heart Journal, determined that the strongest relationships between the vascular risks and the brain were with parts of the brain in control of our complex thinking skills, which are what deteriorate as dementia develops.
Dr. Simon Cox, a senior research associate at the Centre for Cognitive Ageing and Cognitive Epidemiology at the University of Edinburgh, led the researchers.
“The associations between risk factors and brain health and structure were not evenly spread across the whole brain; rather, the areas affected were mainly those known to be linked to our more complex thinking skills and to those areas that show changes in dementia and ‘typical’ Alzheimer’s disease,” Cox said in a statement.
“Although the differences in brain structure were generally quite small, these are only a few possible factors of a potentially huge number of things that might affect brain ageing,” he added.
Cox and his colleagues examined the MRI brain scans of 9,772 people between the ages of 44 and 79, enrolled in the UK Biobank study, which has brain imaging and general health and medical information of hundreds of thousands of volunteer participants.
Researchers analyzed the selected brain scans and looked for relationships between brain structure and seven vascular risk factors that have been potentially linked to reduced blood flow to the brain.
Those risk factors were: smoking, high blood pressure, high pulse pressure, diabetes, high cholesterol levels, obesity as measured by body mass index (BMI) and waist-hip ratio.
Even in middle-age, otherwise healthy adults, researchers found that higher vascular risks correlated with worse brain structure, Cox said. The more risk factors a person had, the more unhealthy their brain was.
Cox said his research could give people more incentive to improve their vascular health through lifestyle changes, because it could affect more than just their respiratory system or heart.
“Lifestyle factors are much easier to change than things like your genetic code — both of which seem to affect susceptibility to worse brain and cognitive aging. Because we found the associations were just as strong in mid-life as they were in later life, it suggests that addressing these factors early might mitigate future negative effects,” Cox said.