Affiliations: [a] Department of Neurology, G. da Saliceto Hospital, Piacenza, Italy
| [b] Alzheimer Center, Briolini Hospital, Gazzaniga, Bergamo, Italy
| [c] Department of Psychology, Sigmund Freud University, Milano, Italy
| [d] Department of Nuclear Medicine, Azienda Ospedaliero-Universitaria, Parma, Italy
| [e] Department of Medicine and Surgery, Section of Neuroscience, University of Parma, Parma, Italy
Correspondence:
[*]
Correspondence to: Marco Spallazzi, Department of Neurology, G. da Saliceto Hospital, Via Cantone del Cristo 40, 29121, Piacenza, Italy. Tel.: +39 0523/703324; E-mail: m.spallazzi@ausl.pc.it.
Abstract: Background:Amyloid pathology is a key feature of Alzheimer’s disease (AD) and can be assessed in vivo with amyloid positron emission tomography (PET) imaging. Objective:The objective of this study was to evaluate the incremental value of a PET scan with [18F]florbetaben, in terms of changes of diagnosis, diagnostic confidence, and treatment plan when added to a standardized diagnostic workup for cognitive disorders, with particular focus on the role of the neuropsychological assessment, including the Free and Cued Selective Reminding Test (FCSRT). Methods:A total of 104 patients (69 mild cognitive impairment, 35 dementia), with diagnostic uncertainty after diagnostic workup, were recruited from our memory clinic. [18F]florbetaben PET scans were interpreted as amyloid negative or positive on the basis of a semi-quantitative visual rating. Clinical diagnosis and diagnostic confidence for AD or non-AD dementia were rated before and after PET result disclosure, as was the impact of PET on the patient management plan. Results:There were 69/104 (66%) [18F]florbetaben positive scans, 51/62 (82%) patients were suspected as having AD before the PET scan and 18/42 (43%) were not. Overall, the data obtained at PET changed 18/104 diagnoses (17%) and increased diagnostic confidence from 69.1±8.1% to 83.5±9.1 (p < 0.001), with the greatest impact on diagnosis and confidence in PET negative patients with an initial diagnosis of AD (p < 0.01) and in early-onset patients (p = 0.01). Conclusion:Amyloid PET represents a source of added value in dementia diagnosis, with a significant effect on diagnosis and diagnostic confidence. However, the use of a complete neuropsychological assessment has an add-on value on limiting the amyloid PET influence on change of diagnosis, and the real impact of amyloid PET should always be weighed up together with an accurate standardized diagnostic workup.
