Men are more likely to suffer problems with memory than women as they grow older, according to scientists.
Mild cognitive impairment (MCI) is a level of mental decline beyond that of normal ageing, and was found to be 1.5 times higher in males.
Scientists conducting the research tested the memory and thinking skills of more than 2,000 people aged 70 to 89 in the US state of Minnesota.
Almost 14% of participants had MCI, 10% showed signs of dementia and 76% had normal mental faculties. But 19% of men had MCI, compared with just 14% of women.
Lead researcher, Dr Ronald Petersen, from the Mayo Clinic in Rochester, Minnesota, said: "If these results are confirmed in other studies, it may suggest that factors related to gender play a role in the disease. For example, men may experience cognitive decline earlier in life but more gradually, whereas women may transition from normal memory directly to dementia at a later age but more quickly."
MCI is often associated with Alzheimer's disease later in life. Participants who had a low level of education or were never married are also shown to have raised rates of MCI.