@article {8709, title = {Sex Differences in Cognitive Decline Among US Adults.}, journal = {JAMA Netw Open}, volume = {4}, year = {2021}, month = {2021 02 01}, pages = {e210169}, abstract = {

Importance: Sex differences in dementia risk are unclear, but some studies have found greater risk for women.

Objective: To determine associations between sex and cognitive decline in order to better understand sex differences in dementia risk.

Design, Setting, and Participants: This cohort study used pooled analysis of individual participant data from 5 cohort studies for years 1971 to 2017: Atherosclerosis Risk in Communities Study, Coronary Artery Risk Development in Young Adults Study, Cardiovascular Health Study, Framingham Offspring Study, and Northern Manhattan Study. Linear mixed-effects models were used to estimate changes in each continuous cognitive outcome over time by sex. Data analysis was completed from March 2019 to October 2020.

Exposure: Sex.

Main Outcomes and Measures: The primary outcome was change in global cognition. Secondary outcomes were change in memory and executive function. Outcomes were standardized as t scores (mean [SD], 50 [10]); a 1-point difference represents a 0.1-SD difference in cognition.

Results: Among 34 349 participants, 26 088 who self-reported Black or White race, were free of stroke and dementia, and had covariate data at or before the first cognitive assessment were included for analysis. Median (interquartile range) follow-up was 7.9 (5.3-20.5) years. There were 11 775 (44.7\%) men (median [interquartile range] age, 58 [51-66] years at first cognitive assessment; 2229 [18.9\%] Black) and 14 313 women (median [interquartile range] age, 58 [51-67] years at first cognitive assessment; 3636 [25.4\%] Black). Women had significantly higher baseline performance than men in global cognition (2.20 points higher; 95\% CI, 2.04 to 2.35 points; P < .001), executive function (2.13 points higher; 95\% CI, 1.98 to 2.29 points; P < .001), and memory (1.89 points higher; 95\% CI, 1.72 to 2.06 points; P < .001). Compared with men, women had significantly faster declines in global cognition (-0.07 points/y faster; 95\% CI, -0.08 to -0.05 points/y; P < .001) and executive function (-0.06 points/y faster; 95\% CI, -0.07 to -0.05 points/y; P < .001). Men and women had similar declines in memory (-0.004 points/y faster; 95\% CI, -0.023 to 0.014; P = .61).

Conclusions and Relevance: The results of this cohort study suggest that women may have greater cognitive reserve but faster cognitive decline than men, which could contribute to sex differences in late-life dementia.

}, keywords = {Aged, Cognitive Dysfunction, Cognitive Reserve, Cohort Studies, Executive Function, Humans, Memory, Middle Aged, Risk, Sex Factors, Time Factors, United States}, issn = {2574-3805}, doi = {10.1001/jamanetworkopen.2021.0169}, author = {Levine, Deborah A and Gross, Alden L and Brice{\~n}o, Emily M and Tilton, Nicholas and Giordani, Bruno J and Sussman, Jeremy B and Hayward, Rodney A and Burke, James F and Hingtgen, Stephanie and Elkind, Mitchell S V and Manly, Jennifer J and Gottesman, Rebecca F and Gaskin, Darrell J and Sidney, Stephen and Sacco, Ralph L and Tom, Sarah E and Wright, Clinton B and Yaffe, Kristine and Galecki, Andrzej T} }