Amyloid-β assessed by florbetapir F 18 PET and 18-month cognitive decline: A multicenter study
Document Type
Article
Abstract
Objectives: Florbetapir F 18 PET can image amyloid-β (Aβ) aggregates in the brains of living subjects. We prospectively evaluated the prognostic utility of detecting Aβ pathology using florbetapir PET in subjects at risk for progressive cognitive decline. Methods: A total of 151 subjects who previously participated in a multicenter florbetapir PET imaging study were recruited for longitudinal assessment. Subjects included 51 with recently diagnosed mild cognitive impairment (MCI), 69 cognitively normal controls (CN), and 31 with clinically diagnosed Alzheimer disease dementia (AD). PET images were visually scored as positive (Aβ+) or negative (Aβ-) for pathologic levels of β-amyloid aggregation, blind to diagnostic classification. Cerebral to cerebellar standardized uptake value ratios (SUVr) were determined from the baseline PET images. Subjects were followed for 18 months to evaluate changes in cognition and diagnostic status. Analysis of covariance and correlation analyses were conducted to evaluate the association between baseline PET amyloid status and subsequent cognitive decline. Results: In both MCI and CN, baseline Aβ+ scans were associated with greater clinical worsening on the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog (p < 0.01) and Clinical Dementia Rating-sum of boxes (CDR-SB) (p < 0.02). In MCI Aβ+ scans were also associated with greater decline in memory, Digit Symbol Substitution (DSS), and Mini-Mental State Examination (MMSE) (p < 0.05). In MCI, higher baseline SUVr similarly correlated with greater subsequent decline on the ADAS-Cog (p < 0.01), CDR-SB (p < 0.03), a memory measure, DSS, and MMSE (p < 0.05). Aβ+ MCI tended to convert to AD dementia at a higher rate than Aβ- subjects (p < 0.10). Conclusions: Florbetapir PET may help identify individuals at increased risk for progressive cognitive decline. © 2012 by AAN Enterprises, Inc.
Publication Date
10-16-2012
Publication Title
Neurology
ISSN
00283878
E-ISSN
1526632X
Volume
79
Issue
16
First Page
1636
Last Page
1644
PubMed ID
22786606
Digital Object Identifier (DOI)
10.1212/WNL.0b013e3182661f74
Recommended Citation
Doraiswamy, P. Murali; Sperling, Reisa A.; Coleman, R. Edward; Johnson, Keith A.; Reiman, Eric M.; Davis, Mat D.; Grundman, Michael; Sabbagh, Marwan N.; Sadowsky, Carl H.; Fleisher, Adam S.; Carpenter, Alan; Clark, Christopher M.; Joshi, Abhinay D.; Mintun, Mark A.; Skovronsky, Daniel M.; and Pontecorvo, Michael J., "Amyloid-β assessed by florbetapir F 18 PET and 18-month cognitive decline: A multicenter study" (2012). Neurology. 760.
https://scholar.barrowneuro.org/neurology/760