Sex differences and modifiable dementia risk factors synergistically influence memory over the adult lifespan

INTRODUCTION: More women than men develop Alzheimer's disease, yet women perform better and show less decline on episodic memory measures, a contradiction that may be accounted for by modifiable risk factors for dementia. METHODS: Associations among age, sex, modifiable dementia risk factors, and cognition were measured in a cross‐sectional online sample (n = 21,840, ages 18 to 89). RESULTS: Across four tests of associative memory and executive functions, only a Face‐Name Association task revealed sex differences in associative memory that varied by age. Men had worse memory than women (the equivalent of performing similar to someone 4 years older) across ages. Men had larger age differences than women (ie, worse memory in older ages) among people with no to one risk factor, but not those with multiple risk factors. DISCUSSION: Because the relationship between dementia risk factors and age‐related memory differences varies between men and women, sex‐specific dementia prevention approaches are warranted.