Cardiovascular risk and dementia
Atherosclerosis is the leading cause of most cardiovascular disease. At the same time, it is associated with the risk of developing dementia. It is known that in the elderly, cerebral atherosclerosis is associated with mild cognitive impairment and Alzheimer’s disease.
Atherosclerosis and dementia have common predisposing factors. Both conditions are more likely to develop under the influence of known cardiovascular risk factors: hypertension, diabetes mellitus, high blood cholesterol levels, smoking, and a sedentary lifestyle. It is known that in elderly people with pronounced cardiovascular risk factors, the brain receives less glucose.
Atherosclerosis is a slow-moving process that can start at a young age, but is evident only over the years. The first signs of dementia, which can only be detected with special tests, also begin long before the full picture of the disease. However, practically nothing was known about the relationship between preclinical forms of atherosclerosis and dementia.
In the new work, Spanish scientists used data from a study of the course of early atherosclerosis, which involved people aged 40-54 years. None of them had cardiovascular disease.
Over the course of four years, researchers periodically assessed the participants’ risk of developing cardiovascular disease using a special scale (it includes age, smoking, cholesterol and blood glucose levels, blood pressure, and other risk factors). They were also examined for atherosclerosis, which was found in asymptomatic form in all participants. Of the 946 participants, 547 underwent positron emission tomography, which measures the metabolic rate in the brain.
“We found that a higher cardiovascular risk in healthy middle-aged people was associated with decreased metabolism in the parietotemporal regions of the brain, which are involved in memory and learning processes,” said Marta Cortés Canteli of the National Center Cardiac Research in Madrid, co-author of the study.
Metabolism slowed down in the same parts of the brain that suffer from neurodegenerative diseases, such as Alzheimer’s disease. Scientists suggest that this suggests a link between cardiovascular disease and dementia already in middle age. Metabolic indices in the brain were also slower in people with developed atherosclerosis in the carotid arteries.
“We think that cardiovascular risk factors affect the large vessels that carry blood from the heart to the brain, as well as the vessels in the brain itself,” explained Valentin Fuster of the National Center for Cardiac Research in Madrid, lead author research.
The authors of the study do not exclude that the disorders they found in the brain may be a harbinger of the development of dementia many years later. However, there is currently not enough data to be sure. In the future, scientists want to explore this issue in a multi-year study.
Scientists emphasize that their data speaks about the importance of preventing cardiovascular disease in middle age. It has the potential to reduce the risk of not only heart disease but dementia as well.