Article

Cerebrospinal fluid biomarkers, education, brain volume, and future cognition.

Knight Alzheimer’s Disease Research Center, St Louis, MO, USA.
Archives of neurology (Impact Factor: 7.58). 09/2011; 68(9):1145-51. DOI:10.1001/archneurol.2011.192
Source: PubMed

ABSTRACT Cross-sectional studies suggest that the cognitive impact of Alzheimer disease pathology varies depending on education and brain size.
To evaluate the combination of cerebrospinal fluid biomarkers of β-amyloid(42) (Aβ(42)), tau, and phosphorylated tau (ptau(181)) with education and normalized whole-brain volume (nWBV) to predict incident cognitive impairment.
Longitudinal cohort study.
Charles F. and Joanne Knight Alzheimer's Disease Research Center, Washington University, St Louis, Missouri.
A convenience sample of 197 individuals 50 years and older with normal cognition (Clinical Dementia Rating of 0) at baseline observed for a mean of 3.3 years.
Time to Clinical Dementia Rating ≥ 0.5.
Three-factor interactions among the baseline biomarker values, education, and nWBV were found for Cox proportional hazards regression models testing tau (P = .02) and ptau (P = .008). In those with lower tau values, nWBV (hazard ratio [HR], 0.54; 95% confidence interval [CI], 0.31-0.91; P = .02), but not education, was related to time to cognitive impairment. For participants with higher tau values, education interacted with nWBV to predict incident impairment (P = .01). For individuals with lower ptau values, there was no effect of education or nWBV. Education interacted with nWBV to predict incident cognitive impairment in those with higher ptau values (P = .02).
In individuals with normal cognition and higher levels of cerebrospinal fluid tau and ptau at baseline, time to incident cognitive impairment is moderated by education and brain volume as predicted by the cognitive/brain reserve hypothesis.

0 0
 · 
1 Bookmark
 · 
86 Views
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: There is growing recognition that the pathophysiological process of Alzheimer disease (AD) begins many years prior to clinically obvious symptoms, and the concept of a presymptomatic or preclinical stage of AD is becoming more widely accepted. Advances in biomarker studies have enabled detection of AD pathology in vivo in clinically normal older individuals. The predictive value of these biomarkers at the individual patient level, however, remains to be elucidated. The ultimate goal of identifying individuals in the preclinical stages of AD is to facilitate early intervention to delay and perhaps even prevent emergence of the clinical syndrome. A number of challenges remain to be overcome before this concept can be validated and translated into clinical practice.
    Nature Reviews Neurology 11/2012; · 15.52 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: The Dementia Risk Assessment (DRA) is an online tool consisting of questions about known risk factors for dementia, a novel verbal memory test, and an informant report of cognitive decline. Its primary goal is to educate the public about dementia risk factors and encourage clinical evaluation where appropriate. In Study 1, more than 3,000 anonymous persons over age 50 completed the DRA about themselves; 1,000 people also completed proxy reports about another person. Advanced age, lower education, male sex, complaints of severe memory impairment, and histories of cerebrovascular disease, Parkinson's disease, and brain tumor all contributed significantly to poor memory performance. A high correlation was obtained between proxy-reported decline and actual memory test performance. In Study 2, 52 persons seeking first-time evaluation at dementia clinics completed the DRA prior to their visits. Their responses (and those of their proxy informants) were compared to the results of independent evaluation by geriatric neuropsychiatrists. The 30 patients found to meet criteria for probable Alzheimer's disease, vascular dementia, or frontotemporal dementia differed on the DRA from the 22 patients without dementia (most other neuropsychiatric conditions). Scoring below criterion on the DRA's memory test had moderately high predictive validity for clinically diagnosed dementia. Although additional studies of larger clinical samples are needed, the DRA holds promise for wide-scale screening for dementia risk.
    PLoS ONE 01/2013; 8(2):e57476. · 3.73 Impact Factor

Full-text

View
34 Downloads
Available from
Aug 22, 2013