Mothers may be more likely to pass down Alzheimer’s disease to their children than fathers, a finding that may help identify patients earlier, researchers from the University of Kansas School of Medicine said.

Healthy older adults with no cognitive problems whose mothers had Alzheimer’s disease had more brain shrinkage than those who had a father or no parent with the disease, according to research published today in the journal Neurology.

About 5.3 million Americans have Alzheimer’s disease and the number may increase to as much as 16 million by 2050, according to the Alzheimer’s Association. Age and family history are the two biggest risk factors for developing the disease, the researchers said. Today’s study provides more details on the biology behind the disease, study author Jeffrey Burns said. 

“Our data is another piece to this puzzle that suggests that maternal inheritance is more important than paternal,” said Burns, director of the Alzheimer and Memory Program at the University of Kansas Medical Center in Kansas City, in a Feb. 25 telephone interview. “It appears that maternal factors might be imparting some risk that we don’t see coming from paternal or lack of family history.”

Researchers analyzed 53 people ages 60 and older who had no signs of dementia. Of those, 11 had mothers with the disease and 10 had fathers with the condition. They then were given brain scans and cognitive tests over the two-year study.

Study Results

The brain’s gray matter, which is part of nerve cells responsible for processing signals, shrank twice as much over the two years in study participants who reported their mothers had Alzheimer’s compared with those who had a father with the disease or no family history of the illness, the researchers said. Those whose mothers had the condition also saw the size of their brains decrease more than those whose fathers had the disease, according to the researchers.

Brain atrophy, or shrinkage of the brain, occurs in Alzheimer’s disease, the researchers said.

Whether those in the study will develop Alzheimer’s disease remains to be seen, Burns said. The researchers are continuing to follow the participants. Also, larger studies are needed to replicate these findings, he said.

People whose mothers have Alzheimer’s shouldn’t panic after reading these results, said Marc L. Gordon, a neurologist and Alzheimer’s researcher at the Feinstein Institute for Medical Research in Manhasset, New York.

“It’s very important to recognize a risk factor is not the same thing as being absolutely certain someone will get the disease,” Gordon, who wasn’t an author on today’s paper, said in a Feb. 25 telephone interview. “It’s an increased risk but it doesn’t mean you will certainly get this.”

The study was funded by the U.S. National Institutes of Health.

(Bloomberg)