title: Will PET amyloid imaging lead to overdiagnosis of Alzheimer dementia?
abstract: Alzheimer disease (AD), a progressive neurodegenerative disease that causes dementia, affects millions of elderly Americans and represents a growing problem with the aging of the population. There has been an increasing effort for improved and earlier diagnosis for AD. Several newly developed radiolabeled compounds targeting β-amyloid plaques, one of the major pathologic biomarkers of AD, have recently become available for clinical use. These radiopharmaceuticals allow for in vivo noninvasive visualization of abnormal β-amyloid deposits in the brain using positron emission tomography (PET). Amyloid PET imaging has demonstrated high sensitivity for pathologic cerebral amyloid deposition in multiple studies. Principal drawbacks to this new diagnostic test are declining specificity in older age groups and uncertain clinical role given lack of disease-modifying therapy for AD. Although there is strong evidence for the utility of amyloid PET in certain situations, detailed in a set of guidelines for appropriate use from the Alzheimer's Association and the Society of Nuclear Medicine and Molecular Imaging, the question of overdiagnosis, the diagnosis of a disease that would result in neither symptoms nor deaths, using this new medical tool needs to be carefully considered in light of efforts to secure reimbursement for the new technology that is already widely available for use as a clinical tool.
authors.affiliation: Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, 3400 Spruce Street, 110 Donner Building, Philadelphia, PA 19104. Electronic address: jacob.dubroff@uphs.upenn.edu.
authors.forename: Jacob G
authors.initials: JG
authors.lastname: Dubroff
authors.affiliation: Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, 3400 Spruce Street, 110 Donner Building, Philadelphia, PA 19104.
authors.forename: Ilya M
authors.initials: IM
authors.lastname: Nasrallah
mesh_terms: D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000378:metabolism*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D019317:Evidence-Based Medicine; D006801:Humans; D000069342:Medical Overuse / Q000639:trends*; D057054:Molecular Imaging / Q000639:trends*; D049268:Positron-Emission Tomography / Q000639:trends*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers
keywords: Alzheimer's disease; Overdiagnosis; amyloid; positron emission tomography