Dataset Information

Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease.

ABSTRACT:

Objective

To compare the diagnostic accuracy of CSF biomarkers and amyloid PET for diagnosing early-stage Alzheimer disease (AD).

Methods

From the prospective, longitudinal BioFINDER study, we included 122 healthy elderly and 34 patients with mild cognitive impairment who developed AD dementia within 3 years (MCI-AD). ?-Amyloid (A?) deposition in 9 brain regions was examined with [18F]-flutemetamol PET. CSF was analyzed with INNOTEST and EUROIMMUN ELISAs. The results were replicated in 146 controls and 64 patients with MCI-AD from the Alzheimer's Disease Neuroimaging Initiative study.

Results

The best CSF measures for identifying MCI-AD were A?42/total tau (t-tau) and A?42/hyperphosphorylated tau (p-tau) (area under the curve [AUC] 0.93-0.94). The best PET measures performed similarly (AUC 0.92-0.93; anterior cingulate, posterior cingulate/precuneus, and global neocortical uptake). CSF A?42/t-tau and A?42/p-tau performed better than CSF A?42 and A?42/40 (AUC difference 0.03-0.12, p<0.05). Using nonoptimized cutoffs, CSF A?42/t-tau had the highest accuracy of all CSF/PET biomarkers (sensitivity 97%, specificity 83%). The combination of CSF and PET was not better than using either biomarker separately.

Conclusions

Amyloid PET and CSF biomarkers can identify early AD with high accuracy. There were no differences between the best CSF and PET measures and no improvement when combining them. Regional PET measures were not better than assessing the global A? deposition. The results were replicated in an independent cohort using another CSF assay and PET tracer. The choice between CSF and amyloid PET biomarkers for identifying early AD can be based on availability, costs, and doctor/patient preferences since both have equally high diagnostic accuracy.

Classification of evidence

This study provides Class III evidence that amyloid PET and CSF biomarkers identify early-stage AD equally accurately.

SUBMITTER: Palmqvist S

PROVIDER: S-EPMC4607601 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Publications

Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease.

Palmqvist Sebastian S Zetterberg Henrik H Mattsson Niklas N Johansson Per P Minthon Lennart L Blennow Kaj K Olsson Mattias M Hansson Oskar O

Neurology 20150909 14

<h4>Objective</h4>To compare the diagnostic accuracy of CSF biomarkers and amyloid PET for diagnosing early-stage Alzheimer disease (AD).<h4>Methods</h4>From the prospective, longitudinal BioFINDER study, we included 122 healthy elderly and 34 patients with mild cognitive impairment who developed AD dementia within 3 years (MCI-AD). β-Amyloid (Aβ) deposition in 9 brain regions was examined with [18F]-flutemetamol PET. CSF was analyzed with INNOTEST and EUROIMMUN ELISAs. The results were replicat ...[more]

PMID: 26354982

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Dataset Information

Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease.

Objective

Methods

Results

Conclusions

Classification of evidence

Publications

Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease.

Similar Datasets

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