A Biomarker for Alzheimer ’s Disease Based on Patterns of Regional Brain Atrophy
In this study, we developed a structural MR-based biomarker for in vivo detection of AD using a supervised machine learning approach. Based on an individual’s pattern of brain atrophy a continuous AD score is assigned which measures the similarity with brain atrophy patterns seen in clinical cases of AD.Methods: The underlying statistical model was trained with MR scans of patients and healthy controls from the Alzheimer’s Disease Neuroimaging Initiative (ADNI-1 screening). Validation was performed within ADNI-1 and in an independent patient sample from the Open Access Series of Imaging Studies (OASIS-1). In addition, our analyses included data from a large general population sample of the Study of Health in Pomerania (SHIP-Trend).Results: Based on the proposed AD score we were able to differentiate patients from healthy controls in ADNI-1 and OASIS-1 with an accuracy of 89% (AUC = 95%) and 87% (AUC = 93%), respectively. Moreover, we found the AD score to be significantly associated with cognitive functioning as assessed by the Mini-Mental State Examination in the OASIS-1 sample after correcting for diagnosis, age, sex, age·sex, and total intracranial volume (Cohen’s f2 = 0.13). Additional analyses showed that the prediction accuracy of AD status based on both the AD score and the MMSE score is significantly higher than when using just one of them. In SHIP-Trend we found the AD score to be weakly but significantly associated with a test of verbal memo...
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This article was corrected online.
AbstractAccurate, automated white matter hyperintensity (WMH) segmentations are needed for large-scale studies to understand contributions of WMH to neurological diseases. We evaluated Bayesian Model Selection (BaMoS), a hierarchical fully-unsupervised model selection framework for WMH segmentation. We compared BaMoS segmentations to semi-automated segmentations, and assessed whether they predicted longitudinal cognitive change in control, early Mild Cognitive Impairment (EMCI), late Mild Cognitive Impairment (LMCI), subjective/significant memory concern (SMC) and Alzheimer ’s (AD) participants. Data were downloaded ...
DISCUSSION: Our independently validated machine-learning model predicted cognitive decline in sporadic prodromal AD and may substantially reduce sample size needed in clinical trials in AD. PMID: 32043733 [PubMed - as supplied by publisher]
CONCLUSION: Our findings show that hippocampal subfield atrophy varies among the three study groups. PMID: 32008518 [PubMed - in process]
No abstract available
(Wiley) New findings published in the Scandinavian Journal of Medicine&Science in Sports reveal how physically active older adults benefit from reduced risks of early death, breast and prostate cancer, fractures, recurrent falls, functional limitations, cognitive decline, dementia, Alzheimer's disease, and depression.
ConclusionThe presence of microbleeds in DLB is associated with higher blood pressure, but not with other measures of vascular disease or amyloid deposition. The relationship between microbleeds and clinical presentation remains unclear.
In Reply The Letter to the Editor by Montero-Odasso and colleagues addresses noncognitive manifestations of Alzheimer disease (AD). Their letter discusses a recent article from the Mayo Clinic. Using positron emission tomography biomarkers of amyloidosis (A) and tauopathy (T), the Mayo study examined the age- and sex-specific prevalence of 3 biologically defined entities: amyloidosis (A+) regardless of tau status, A+T −, and A+T+. We compared the age and sex specific prevalence of these 3 biomarker-defined entities with 3 clinical syndromes commonly associated with AD: clinically defined probable AD using the McKhann...
Conclusion: Tau accumulation likely started in the more affected anterior node and, at the disease stage at which we studied these patients, appeared as well in the brain region (in the temporal lobe) spatially separate from but most connected with it. The arcuate fasciculus, connecting both of them, was most severely affected anteriorly, as would correspond to a loss of axons from the anterior node. These findings are suggestive of tau propagation from node to connected node in a natural human brain network and support the idea that neurons that wire together die together.