@article {8919, title = {Pre-Statistical Considerations for Harmonization of Cognitive Instruments: Harmonization of ARIC, CARDIA, CHS, FHS, MESA, and NOMAS.}, journal = {J Alzheimers Dis}, volume = {83}, year = {2021}, month = {2021}, pages = {1803-1813}, abstract = {

BACKGROUND: Meta-analyses of individuals{\textquoteright} cognitive data are increasing to investigate the biomedical, lifestyle, and sociocultural factors that influence cognitive decline and dementia risk. Pre-statistical harmonization of cognitive instruments is a critical methodological step for accurate cognitive data harmonization, yet specific approaches for this process are unclear.

OBJECTIVE: To describe pre-statistical harmonization of cognitive instruments for an individual-level meta-analysis in the blood pressure and cognition (BP COG) study.

METHODS: We identified cognitive instruments from six cohorts (the Atherosclerosis Risk in Communities Study, Cardiovascular Health Study, Coronary Artery Risk Development in Young Adults study, Framingham Offspring Study, Multi-Ethnic Study of Atherosclerosis, and Northern Manhattan Study) and conducted an extensive review of each item{\textquoteright}s administration and scoring procedures, and score distributions.

RESULTS: We included 153 cognitive instrument items from 34 instruments across the six cohorts. Of these items, 42\%were common across >=2 cohorts. 86\%of common items showed differences across cohorts. We found administration, scoring, and coding differences for seemingly equivalent items. These differences corresponded to variability across cohorts in score distributions and ranges. We performed data augmentation to adjust for differences.

CONCLUSION: Cross-cohort administration, scoring, and procedural differences for cognitive instruments are frequent and need to be assessed to address potential impact on meta-analyses and cognitive data interpretation. Detecting and accounting for these differences is critical for accurate attributions of cognitive health across cohort studies.

}, issn = {1875-8908}, doi = {10.3233/JAD-210459}, author = {Brice{\~n}o, Emily M and Gross, Alden L and Giordani, Bruno J and Manly, Jennifer J and Gottesman, Rebecca F and Elkind, Mitchell S V and Sidney, Stephen and Hingtgen, Stephanie and Sacco, Ralph L and Wright, Clinton B and Fitzpatrick, Annette and Fohner, Alison E and Mosley, Thomas H and Yaffe, Kristine and Levine, Deborah A} } @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} }