RT Journal Article
SR Electronic
T1 Effect of intellectual enrichment on AD biomarker trajectories
JF Neurology
JO Neurology
FD Lippincott Williams & Wilkins
SP 1128
OP 1135
DO 10.1212/WNL.0000000000002490
VO 86
IS 12
A1 Vemuri, Prashanthi
A1 Lesnick, Timothy G.
A1 Przybelski, Scott A.
A1 Knopman, David S.
A1 Machulda, Mary
A1 Lowe, Val J.
A1 Mielke, Michelle M.
A1 Roberts, Rosebud O.
A1 Gunter, Jeffrey L.
A1 Senjem, Matthew L.
A1 Geda, Yonas E.
A1 Rocca, Walter A.
A1 Petersen, Ronald C.
A1 Jack, Clifford R.
YR 2016
UL http://n.neurology.org/content/86/12/1128.abstract
AB Objective: To investigate the effect of age, sex, APOE4 genotype, and lifestyle enrichment (education/occupation, midlife cognitive activity, and midlife physical activity) on Alzheimer disease (AD) biomarker trajectories using longitudinal imaging data (brain β-amyloid load via Pittsburgh compound B PET and neurodegeneration via 18fluorodeoxyglucose (FDG) PET and structural MRI) in an elderly population without dementia.Methods: In the population-based longitudinal Mayo Clinic Study of Aging, we studied 393 participants without dementia (340 clinically normal, 53 mild cognitive impairment; 70 years and older) who had cognitive and physical activity measures and at least 2 visits with imaging biomarkers. We dichotomized participants into high (≥14 years) and low (<14 years) education levels using the median. For the entire cohort and the 2 education strata, we built linear mixed models to investigate the effect of the predictors on each of the biomarker outcomes.Results: Age was associated with amyloid and neurodegeneration trajectories; APOE4 status appears to influence only the amyloid and FDG trajectories but not hippocampal volume trajectory. In the high-education stratum, high midlife cognitive activity was associated with lower amyloid deposition in APOE4 carriers. APOE4 status was associated with lower FDG uptake in the entire cohort and in participants with lower education but not the high-education cohort.Conclusions: There were minimal effects of lifestyle enrichment on AD biomarker trajectories (specifically rates). Lifetime intellectual enrichment (high education, high midlife cognitive activity) is associated with lower amyloid in APOE4 carriers. High education is protective from the APOE4 effect on FDG metabolism. Differing education levels may explain the conflicting results seen in the literature.AD=Alzheimer disease; FDG=18fluorodeoxyglucose; MCI=mild cognitive impairment; MCSA=Mayo Clinic Study of Aging; MET=metabolic equivalent; MPRAGE=magnetization-prepared rapid gradient echo; PCA=principal components analysis; PiB=Pittsburgh compound B; ROI=region of interest; TIV=total intracranial volume