2 Parents With Alzheimer's, Higher Risk of This?
Small study found these people had more beta-amyloid deposits, less gray matter
For the current study, Mosconi's team recruited 52 healthy adults to undergo MRI and PET scans of the brain. They were split evenly into four groups of 13: those with two parents who had Alzheimer's, those with an affected mother, those with an affected father and those with two Alzheimer's-free parents.
Overall, the study found, the group with two affected parents showed more Alzheimer's-linked brain abnormalities. They had, for example, 5 percent to 10 percent more beta-amyloid deposits than the other three groups. They also showed the lowest volume of gray matter and a slower metabolism of glucose, the brain's main fuel.
In general, Mosconi said, the study saw a "parent-dose" pattern: People with two Alzheimer's-affected parents had the highest level of disease indicators, followed by people whose mother was affected, and then those with an affected father.
Another expert said the finding of a higher risk in the mother-only group is interesting.
Past research has suggested that people's risk of Alzheimer's might be higher when a mother, rather than a father, was affected, said Jeremy Silverman, a professor of psychiatry at the Mount Sinai Icahn School of Medicine in New York City.
If that's true, it could offer hints about the genetic roots of Alzheimer's, he said. There is, for example, a type of DNA -- called mitochondrial DNA -- that's inherited only from mothers.
For now, there is no real-world use for the findings.
"You definitely aren't going to run out and have these [indicators] measured," Kanner said.
Even if the indicators do turn out to predict an increased Alzheimer's risk, there is currently nothing doctors can do about it.
If researchers can develop drugs that help prevent the disease, Mosconi said, one can imagine a future in which people with a strong family history of Alzheimer's undergo a brain scan to look for early markers for the disease.
The ideal scenario, she said, would be to give preventive treatments to people at high risk of Alzheimer's who are not yet showing symptoms.
Silverman said researchers are looking for various ways to intervene early. So far, he said, "intervention efforts with [patients] who are already showing clinical signs of Alzheimer's have largely not been successful in meaningfully treating the illness."
For now, Mosconi said, people with a strong family history of Alzheimer's can focus on the lifestyle measures recommended for everyone -- such as a healthy diet and regular exercise.
Studies have linked the same factors that can damage the heart -- such as high blood pressure, high cholesterol, obesity and diabetes -- to an increased risk of Alzheimer's.
Those studies, and the latest research, don't prove cause-and-effect. But, Mosconi said, there are already plenty of other reasons to maintain a healthy lifestyle.