Family history is a key risk factor for Alzheimer’s, and now a new study adds to the evidence that the risk of the disease is greater if you have it on your mother’s side than on your father’s.
Researchers at the University of Kansas School of Medicine studied 53 mentally healthy adults over 60 years old. Twenty-one participants had parents with Alzheimer’s: 10 had a father with Alzheimer’s, and 11 had a mother with the disease. The rest had no family history.
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The participants underwent MRI brain scans at the start of the study and again two years later. Although all volunteers were still cognitively intact at the two-year mark, researchers found that those who had a family history of Alzheimer’s had lost more gray matter in the brain than their peers. Moreover, people whose mothers had Alzheimer’s showed significantly more brain atrophy than people whose fathers were affected by the disease.
After two years, people whose mothers had Alzheimer’s had twice the amount of gray matter atrophy, or shrinkage, in brain regions known to be affected by Alzheimer’s compared to those with a paternal history or no family history of the disease. The regions included the parahippocampal gyrus and the precuneus.
Those with a maternal history of Alzheimer’s also had one and a half times more loss in whole brain volume each year compared to those with a paternal history or no family history of the disease.
Brain atrophy is correlated with dementia and Alzheimer’s, but small amounts of shrinkage is normal as people age. Researchers hope to use tools like brain scans and blood tests to predict Alzheimer’s risk early on, long before symptoms arise.
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