Authors
Samantha Burnham
Noel Faux
William Wilson
Simon Laws, Edith Cowan UniversityFollow
David Ames
Justin Bedo
Ashley Bush
James Doecke
Kathryn Ellis
Richard Head
Gareth Jones
Harri Kiiveri
Ralph N. Martins, Edith Cowan UniversityFollow
Alan Rembach
Christopher Rowe
Olivier Salvado
S Lance Macaulay
Colin Masters
Victor Villemagne
Document Type
Journal Article
Publisher
Nature Publishing Group
Faculty
Faculty of Health, Engineering and Science
School
School of Medical Sciences / Centre of Excellence for Alzheimer's Disease Research and Care
RAS ID
16877
Abstract
Dementia is a global epidemic with Alzheimer’s disease (AD) being the leading cause. Early identification of patients at risk of developing AD is now becoming an international priority. Neocortical Aβ (extracellular β-amyloid) burden (NAB), as assessed by positron emission tomography (PET), represents one such marker for early identification. These scans are expensive and are not widely available, thus, there is a need for cheaper and more widely accessible alternatives. Addressing this need, a blood biomarker-based signature having efficacy for the prediction of NAB and which can be easily adapted for population screening is described. Blood data (176 analytes measured in plasma) and Pittsburgh Compound B (PiB)-PET measurements from 273 participants from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study were utilised. Univariate analysis was conducted to assess the difference of plasma measures between high and low NAB groups, and cross-validated machine-learning models were generated for predicting NAB. These models were applied to 817 non-imaged AIBL subjects and 82 subjects from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) for validation. Five analytes showed significant difference between subjects with high compared to low NAB. A machine-learning model (based on nine markers) achieved sensitivity and specificity of 80 and 82%, respectively, for predicting NAB. Validation using the ADNI cohort yielded similar results (sensitivity 79% and specificity 76%). These results show that a panel of blood-based biomarkers is able to accurately predict NAB, supporting the hypothesis for a relationship between a blood-based signature and Aβ accumulation, therefore, providing a platform for developing a population-based screen
DOI
10.1038/mp.2013.40
Access Rights
free_to_read
Comments
This is an Author's Accepted Manuscript of: Burnham, S., Faux, N., Wilson, W., Laws, S. , Ames, D., Bedo, J., Bush, A., Doecke, J., Ellis, K., Head, R., Jones, G., Kiiveri, H., Martins, R. N., Rembach, A., Rowe, C., Salvado, O., Macaulay, S., Masters, C., & Villemagne, V. (2014). A blood-based predictor for neocortical Aβ burden in Alzheimer's disease: results from the AIBL study. Molecular Psychiatry, 19(4), 519-526. Available here