New York, Oct 8 (IANS): Early detection of Alzheimer's disease in women may be more difficult than in men, because they tend to retain better verbal memory even when their brains show the same level of problems associated with the disease, a study has found.

Tests on verbal memory -- the ability to recall words and other verbal items -- is used as a means to diagnose people with mild cognitive impairment and Alzheimer's, a progressive disease that destroys memory and other important mental functions.

"Women perform better than men on tests of verbal memory throughout life, which may give them a buffer of protection against losing their verbal memory skills in the precursor stages of Alzheimer's disease, known as mild cognitive impairment," said Erin E. Sundermann from the University of California - San Diego, US

The findings suggest that women are better able to compensate for underlying changes in the brain with their "cognitive reserve" until the disease reaches a more advanced stage.

As a result, their Alzheimer's may not be diagnosed until they are further along in the disease, Sundermann added.

For the study, the team performed a memory test on 254 persons with Alzheimer's disease, 672 persons with mild cognitive impairment that included memory problems and 390 persons with no thinking or memory problems.

Women scored better than men on the memory tests when they had no, mild or moderate problems with brain metabolism.

"If these results are confirmed, adjusting memory tests to account for the differences between men and women may help diagnose Alzheimer's disease earlier in women," Sundermann said in the paper published online in the journal Neurology.