PT  - JOURNAL ARTICLE
AU  - Gidicsin, Christopher M.
AU  - Maye, Jacqueline E.
AU  - Locascio, Joseph J.
AU  - Pepin, Lesley C.
AU  - Philiossaint, Marlie
AU  - Becker, J. Alex
AU  - Younger, Alayna P.
AU  - Dekhtyar, Maria
AU  - Schultz, Aaron P.
AU  - Amariglio, Rebecca E.
AU  - Marshall, Gad A.
AU  - Rentz, Dorene M.
AU  - Hedden, Trey
AU  - Sperling, Reisa A.
AU  - Johnson, Keith A.
TI  - Cognitive activity relates to cognitive performance but not to Alzheimer disease biomarkers
AID  - 10.1212/WNL.0000000000001704
DP  - 2015 Jul 07
TA  - Neurology
PG  - 48--55
VI  - 85
IP  - 1
4099  - http://n.neurology.org/content/85/1/48.short
4100  - http://n.neurology.org/content/85/1/48.full
SO  - Neurology2015 Jul 07; 85
AB  - Objective: We aimed to determine whether there was a relationship between lifestyle factors and Alzheimer disease biomarkers.Methods: In a cross-sectional study, we evaluated self-reported histories of recent and past cognitive activity, self-reported history of recent physical activity, and objective recent walking activity in 186 clinically normal individuals with mean age of 74 ± 6 years. Using backward elimination general linear models, we tested the hypotheses that greater cognitive or physical activity would be associated with lower Pittsburgh compound B–PET retention, greater 18F-fluorodeoxyglucose–PET metabolism, and larger hippocampal volume, as well as better cognitive performance on neuropsychological testing.Results: Linear regression demonstrated that history of greater cognitive activity was correlated with greater estimated IQ and education, as well as better neuropsychological testing performance. Self-reported recent physical activity was related to objective exercise monitoring. However, contrary to hypotheses, we did not find evidence of an association of Pittsburgh compound B retention, 18F-fluorodeoxyglucose uptake, or hippocampal volume with past or current levels of cognitive activity, or with current physical activity.Conclusions: We conclude that a history of lifelong cognitive activity may support better cognitive performance by a mechanism that is independent of brain β-amyloid burden, brain glucose metabolism, or hippocampal volume.Aβ=β-amyloid; AD=Alzheimer disease; AMNART=American version of the National Adult Reading Test; CA=cognitive activity; FDG=18F-fluorodeoxyglucose; FS=FreeSurfer; GLM=general linear model; mcPiB=mean cortical Pittsburgh compound B; MP-RAGE=magnetization-prepared rapid-acquisition gradient echo; PiB=Pittsburgh compound B; PrecFDG=precuneus 18F-fluorodeoxyglucose; RelHippoVol=relative hippocampal volume; ROI=region of interest; TPASelf=self-reported total physical activity; TWAPed=pedometer-measured total walking activity; WalkSelf=self-reported walking activity