title: Reduced FDG-PET brain metabolism and executive function predict clinical progression in elderly healthy subjects.
abstract: Brain changes reminiscent of Alzheimer disease (AD) have been previously reported in a substantial portion of elderly cognitive healthy (HC) subjects. The major aim was to evaluate the accuracy of MRI assessed regional gray matter (GM) volume, 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), and neuropsychological test scores to identify those HC subjects who subsequently convert to mild cognitive impairment (MCI) or AD dementia. We obtained in 54 healthy control (HC) subjects a priori defined region of interest (ROI) values of medial temporal and parietal FDG-PET and medial temporal GM volume. In logistic regression analyses, these ROI values were tested together with neuropsychological test scores (free recall, trail making test B (TMT-B)) as predictors of HC conversion during a clinical follow-up between 3 and 4 years. In voxel-based analyses, FDG-PET and MRI GM maps were compared between HC converters and HC non-converters. Out of the 54 HC subjects, 11 subjects converted to MCI or AD dementia. Lower FDG-PET ROI values were associated with higher likelihood of conversion (p = 0.004), with the area under the curve (AUC) yielding 82.0% (95% CI = (95.5%, 68.5%)). The GM volume ROI was not a significant predictor (p = 0.07). TMT-B but not the free recall tests were a significant predictor (AUC = 71% (95% CI = 50.4%, 91.7%)). For the combination of FDG-PET and TMT-B, the AUC was 93.4% (sensitivity = 82%, specificity = 93%). Voxel-based group comparison showed reduced FDG-PET metabolism within the temporo-parietal and prefrontal cortex in HC converters. In conclusion, medial temporal and-parietal FDG-PET and executive function show a clinically acceptable accuracy for predicting clinical progression in elderly HC subjects.
authors.affiliation: Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilian-University, Munich, Germany ; Department of Radiology, University of California, San Francisco, CA, USA ; VA Medical Center, Center for Imaging of Neurodegenerative Diseases, San Francisco, CA, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Ewers
authors.forename: Matthias
authors.initials: M
authors.lastname: Brendel
authors.forename: Angela
authors.initials: A
authors.lastname: Rizk-Jackson
authors.forename: Axel
authors.initials: A
authors.lastname: Rominger
authors.forename: Peter
authors.initials: P
authors.lastname: Bartenstein
authors.forename: Norbert
authors.initials: N
authors.lastname: Schuff
authors.forename: Michael W
authors.initials: MW
authors.lastname: Weiner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D000544:Alzheimer Disease / Q000175:diagnosis; D002540:Cerebral Cortex / Q000000981:diagnostic imaging* / Q000473:pathology; D060825:Cognitive Dysfunction / Q000175:diagnosis; D018450:Disease Progression; D056344:Executive Function / Q000502:physiology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D066128:Gray Matter / Q000000981:diagnostic imaging*; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D012372:ROC Curve
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Conversion; Diagnosis; Executive function; FDG-PET; Gray matter volume; Preclinical AD