Effect of Cognitive Reserve on Age-Related Changes in Cerebrospinal Fluid Biomarkers of Alzheimer Disease

• IMPORTANCE Although advancing age is the strongest risk factor for the development of symptomatic Alzheimer disease (AD), recent studies have shown that there are individual differences in susceptibility to age-related alterations in the biomarkers of AD pathophysiology. OBJECTIVE To investigate whether cognitive reserve (CR) modifies the adverse influence of age on key cerebrospinal fluid (CSF) biomarkers of AD. DESIGN, SETTING, AND PARTICIPANTS A cross-sectional cohort of 268 individuals (211 in a cognitively normal group and 57 in a cognitively impaired group) from the Wisconsin Registry for Alzheimer's Prevention and the Wisconsin Alzheimer's Disease Research Center participated in this study. They underwent lumbar puncture for collection of CSF samples, from which A beta 42, total tau (t-tau), and phosphorylated tau (p-tau) were immunoassayed. In addition, we computed t-tau/A beta 42 and p-tau/A beta 42 ratios. Cognitive reserve was indexed by years of education, with 16 or more years taken to confer high reserve. Covariate-adjusted regression analyses were used to test whether the effect of age on CSF biomarkers was modified by CR. The study dates were March 5, 2010, to February 13, 2013. MAIN OUTCOMES AND MEASURES Cerebrospinal fluid levels of A beta 42, t-tau, p-tau, t-tau/A beta 42, and p-tau/A beta 42. RESULTS There were significant age x CR interactions for CSF t-tau (beta [SE] = -6.72 [2.84], P = .02), p-tau (beta [SE] = -0.71 [0.27], P = .01), t-tau/A beta 42 (beta [SE] = -0.02 [0.01], P = .02), and p-tau/A beta 42 (beta [SE] = -0.002 [0.001], P = .004). With advancing age, individuals with high CR exhibited attenuated adverse alterations in these CSF biomarkers compared with individuals with low CR. This attenuation of age effects by CR tended to be more pronounced in the cognitively impaired group compared with the cognitively normal group. There was evidence of a dose-response relationship such that the effect of age on the biomarkers was progressively attenuated given additional years of schooling. CONCLUSIONS AND RELEVANCE In a sample composed of a cognitively normal group and a cognitively impaired group, higher CR was associated with a diminution of age-related alterations in CSF biomarkers of AD. This suggests one pathway through which CR might favorably alter lifetime risk for symptomatic AD.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Geriatrik (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Geriatrics (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Neurologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Neurology (hsv//eng)

Nyckelord

POSITRON-EMISSION-TOMOGRAPHY

PITTSBURGH COMPOUND-B

ASSOCIATION

WORKGROUPS

DIAGNOSTIC GUIDELINES

NATIONAL INSTITUTE

PHYSICAL-ACTIVITY

FDG-PET

EDUCATION

DEMENTIA

BRAIN

Clinical Neurology

ERN Y

1992

ANNALS OF NEUROLOGY

V32

P371

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)