Alzheimer's Disease May Be Passed Down From Ailing Mothers, Study Suggests
Alzheimer's Disease May Be Passed Down From Ailing Mothers, Study Suggests - Bloomberg
By Nicole Ostrow - Feb 28, 2011
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.”
Honea RA, Swerdlow RH, Vidoni ED, Burns JM.
Progressive regional atrophy in normal adults with a maternal history of Alzheimer disease. Neurology 2011;76(9):822-9.
Progressive regional atrophy in normal adults with a maternal history of Alzheimer disease
Objective: Beyond age, having a family history is the most significant risk factor for Alzheimer disease (AD). This longitudinal brain imaging study examines whether there are differential patterns of regional gray matter atrophy in cognitively healthy elderly subjects with (FH+) and without (FH?) a family history of late-onset AD.
Methods: As part of the KU Brain Aging Project, cognitively intact individuals with a maternal history (FHm, n = 11), paternal history (FHp, n = 10), or no parental history of AD (FH?, n = 32) similar in age, gender, education, and Mini-Mental State Examination (MMSE) score received MRI at baseline and 2-year follow-up. A custom voxel-based morphometry processing stream was used to examine regional differences in atrophy between FH groups, controlling for age, gender, and APOE ?4 (APOE4) status. We also analyzed APOE4-related atrophy.
Results: Cognitively normal FH+ individuals had significantly increased whole-brain gray matter atrophy and CSF expansion compared to FH?. When FH+ groups were split, only FHm was associated with longitudinal measures of brain change. Moreover, our voxel-based analysis revealed that FHm subjects had significantly greater atrophy in the precuneus and parahippocampus/hippocampus regions compared to FH? and FHp subjects, independent of APOE4 status, gender, and age. Individuals with an ?4 allele had more regional atrophy in the frontal cortex compared to ?4 noncarriers.
Conclusions: We conclude that FHm individuals without dementia have progressive gray matter volume reductions in select AD-vulnerable brain regions, specifically the precuneus and parahippocampal gyrus. These data complement and extend reports of regional cerebral metabolic differences and increases in amyloid-? burden in FHm subjects, which may be related to a higher risk for developing AD.