Sex differences in Alzheimer's disease.

Abstract

Women are more impacted by Alzheimer's disease than men - they are at significantly greater risk of developing Alzheimer's disease, and recent research shows that they also appear to suffer a greater cognitive deterioration than men at the same disease stage. The purpose of this article is to review recent studies on examining sex differences in cognitive function in Alzheimer's disease. We searched electronically for articles, reviews and meta-analyses published between 1/2016 and 12/2017 and identified 298 articles on sex differences in cognition in Alzheimer's disease. The key themes to emerge were sex differences in cognitive function, risk factors, resilience, and cognitive reserve. Evidence is steadily and increasingly accumulating to confirm the poorer cognitive outcome for women than men with Alzheimer's disease. Although small in size, the effects occur across a broad range of cognitive domains including visuospatial, verbal, episodic memory, and semantic memory - some of which typically reveal a sex-related processing advantage for healthy women. Explanations have been linked to a variety of factors including differences in cognitive reserve, resilience, as well as genetics (apolipoprotein ε4) and functional and structural brain changes. Sex-related differences in risk factors, resilience, cognitive reserve, and rates of deterioration have implications for clinical practice.