Diabetes, air pollution and alcohol consumption could be the biggest risk factors for dementia, a study has found.
Diabetes, air pollution and alcohol consumption each has an effect that is about twice as much as the other leading risk factors, Douaud said. The next major risk factors are sleep, weight, smoking and blood pressure.
Researchers compared modifiable risk factors for dementia — which is characterized by the impairment of memory, thinking and reasoning — and studied how these factors appear to affect certain brain regions that are already particularly vulnerable to Alzheimer’s disease and schizophrenia.
The research, based on brain scans of nearly 40,000 adults, between ages 44 and 82, in Britain was published Wednesday in Nature Communications.
These vulnerable regions of the brain develop during adolescence and help the brain process and integrate “bits of information across different modalities, across different senses,” said Gwenaëlle Douaud, an associate professor at the University of Oxford and co-author of the study. But “they’re the first ones to go when we start aging.”
Washington Post Article: Study finds 3 big risk factors for dementia
Study Paper:
The effects of genetic and modifiable risk factors on brain regions vulnerable to ageing and disease
We have previously identified a network of higher-order brain regions particularly vulnerable to the ageing process, schizophrenia and Alzheimer’s disease. However, it remains unknown what the genetic influences on this fragile brain network are, and whether it can be altered by the most common modifiable risk factors for dementia. Here, in ~40,000 UK Biobank participants, we first show significant genome-wide associations between this brain network and seven genetic clusters implicated in cardiovascular deaths, schizophrenia, Alzheimer’s and Parkinson’s disease, and with the two antigens of the XG blood group located in the pseudoautosomal region of the sex chromosomes. We further reveal that the most deleterious modifiable risk factors for this vulnerable brain network are diabetes, nitrogen dioxide – a proxy for traffic-related air pollution – and alcohol intake frequency. The extent of these associations was uncovered by examining these modifiable risk factors in a single model to assess the unique contribution of each on the vulnerable brain network, above and beyond the dominating effects of age and sex. These results provide a comprehensive picture of the role played by genetic and modifiable risk factors on these fragile parts of the brain.