MRI Study Links Alzheimer’s Disease to Specific Lifestyle Risk Factors

The results of a new study have found that cardiovascular risk factors such as smoking, alcohol consumption, diabetes, and obesity, can be linked directly to smaller brain volumes in specific areas of the brain, and to lower cognitive test scores.

The study was published online in the Radiological Society of North America (RSNA) journal Radiology and shows that the lower brain volumes may be early indicators of Alzheimer’s disease, and dementia. The study focused on specific cardiovascular risk factors and three main regions of the brain used in memory retrieval, namely the precuneus, posterior cingulate cortex, and the hippocampus.

The researchers analyzed results from 1,629 individuals that took part in a heart study—805 individuals under the age of 50, and 824 aged 50 years and older. The researchers looked at the participants’ initial baseline data, including laboratory and clinical tests, and data from a follow-up visit after seven years. The second visit included a brain Magnetic Resonance Imaging (MRI) exam and a test to measure mild cognitive impairment, and indicators of preclinical Alzheimer’s disease. The researchers compared the results and found that lower brain volumes in each area correlated with lower cognitive test scores.

Obesity and smoking were linked with reduced posterior cingulate cortex volumes, while alcohol consumption and diabetes were linked to smaller total brain volume. Alcohol consumption and smoking were also linked to lower hippocampal mass, and obesity, and alcohol use, and high fasting blood glucose numbers were linked to a smaller precuneus.

The researchers concluded that for participants aged 50 and less, a smaller posterior cingulate volume was a possible early risk indicator of cognitive decline, while for participants aged 50 and over, a smaller hippocampus and precuneus may be early risk indicators.

Kevin S. King, MD, assistant professor of radiology at the Keck School of Medicine of the University of Southern California (Los Angeles, CA, USA), said, “We already know that vascular risk factors damage the brain and can result in cognitive impairment. But our findings give us a more concrete idea about the relationship between specific vascular risk factors and brain health. We currently do not have effective treatments for Alzheimer’s disease, so the focus is on prevention. In the future, we may be able to provide patients with useful and actionable information about the impact different risk factors may be having on their brain health during routine clinical imaging. And since no special imaging equipment is needed, there is a great potential to provide this service at many centers across the country.”

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