By Sally Robertson, BSc
A new study has shown that women may have a better memory for words than men in the early stages of Alzheimer’s disease, despite evidence of similar levels of shrinkage in the brain area responsible for verbal memory.
For women, this can mean a disadvantage when it comes to detection of the disease while it is still in the early stages. The study authors say that if further research confirms these results, the tests currently used to diagnose the condition may need to be reinvented.
One way to interpret the results is that because women have better verbal memory skills than men throughout life, women have a buffer of protection against loss of verbal memory before the effects of Alzheimer's disease kick in…”
“Because verbal memory tests are used to diagnose people with Alzheimer's disease and its precursor, mild cognitive impairment, these tests may fail to detect mild cognitive impairment and Alzheimer's disease in women until they are further along in the disease.”
Lead author of the study, Erin Sundermann, Albert Einstein College of Medicine, New York.
As reported in Neurology, the journal of the American Academy of Neurology, the research included 235 people who had Alzheimer’s disease, 694 who had mild cognitive impairment and 379 healthy participants who had no memory or thinking problems.
The participants sat the Rey Auditory Verbal Learning Test, which evaluates memory using spoken words and repetition. The results were compared to the size of the hippocampus in the brain, the area responsible for verbal memory that is affected during the early stages of Alzheimer’s disease.
Among participants who had minimal to moderate atrophy of the hippocampus, women outperformed men for both immediate and delayed recall. Among those with a high level of hippocampal shrinkage, no gender-specific difference between the scores was observed.
However, at the score that does indicate the beginning of verbal memory impairment, women showed evidence of having more advanced hippocampal shrinkage.
“This advantage may represent a sex-specific form of cognitive reserve delaying verbal memory decline until more advanced disease stages,” wrote the authors.
"If these results are confirmed, then we may need to adjust memory tests to account for the difference between men and women in order to improve our accuracy in diagnosis," says Sundermann.