New research shows males generally have worse memory and lower hippocampal volume later in life than women.

The findings suggest that being male is a higher risk factor for memory problems than the APOE?4 gene, which is linked to Alzheimer's disease, the JAMA Network Journals reported.

A team of researchers looked at "age, sex and APOE ?4 effects on memory and brain structure" by examining hippocampal volume and brain plaques (β-amyloidosis) associated with Alzheimer's disease. The study included 1,246 cognitively normal study participants between the ages of 30 and 95.

The data revealed that hippocampal volume (HVa) declined gradually between the ages of 30 and about 65, and more steeply after that. Median amyloid accumulation tended to be low until the age of 70, but increased after that point. Memory proved to be worse in men than women overall, especially in individuals over the age of 40, and HVa was usually lower in men than in women.  APOE ?4 carrier status was not found to have an influence on memory performance or HVa in either males or females, but  APOE ?4 carriers over the age of 70 were observed to have greater median amyloid accumulation than non-carriers.

"We believe that this study of typical aging reveals interesting sex and APOE ?4 effects on age-related trends in brain structure, function and [buildup of plaque deposits in the brain]. To date, these effects have not been widely appreciated. Our findings are consistent with a model of late-onset AD [Alzheimer disease] in which β-amyloidosis arises later in life on a background of preexisting structural and cognitive decline that is associated with aging and not with β-amyloid deposits," the study concluded.

The findings were published in a recent edition of the journal JAMA Neurology.