Almost two-thirds of those with Alzheimer’s disease in the United States are women. 1
The first obvious reason for this is that women live longer, but longevity alone does not explain the large difference.
“Even after correcting for age, women appear to be at greater risk,” said Michael Greicius, MD, assistant professor of neurology and neurological sciences and medical director of the Stanford Center for Memory Disorders told Stanford News.
Greicius is the senior author of a 2014 study that analyzed records of 8,000 people, most of whom were over the age of 60.
The study looked at 2588 people with mild cognitive impairment and 5496 healthy elderly who had visited national Alzheimer’s centers between the years of 2005 and 2013.
The researchers examined what type of APOE genes the men and women had and compared them to their cognitive levels.
There are three APOE variants: APOE2, APOE3 andAPOE4. Most people carry two copies of the APOE3 gene variant (one from each parent).
However, about one in five people carry at least one copy of APOE4. That is the gene that has been found to have a link to Alzheimer’s disease, particularly if the person is female.
A study from 1997 had shown “that females with the APOE4 variant were four times more likely to have Alzheimer’s compared with people with the more common, neutral form of the gene. However, in men, APOE4 seemed virtually harmless,” reported AAAS.ORG.
In this new 2014 study, Greicius and fellow researchers found that “healthy women who inherited the APOE4 variant were twice as likely as non-carriers to develop mild cognitive impairment or Alzheimer’s disease, whereas APOE4 males fared only slightly worse than those without the gene variant,” according to AAAS.ORG.
Greicius stated that knowing the difference between the affect of the APOE4 gene in female and male patients could alert health care providers to take different approaches in the management of Alzheimer’s.