Apathy and striatal dopamine transporter levels in de-novo, untreated Parkinson's disease patients

• Published in: Parkinsonism & related disorders 2015-05, Vol.21 (5), p.489-493
• Main Authors: Santangelo, Gabriella, Vitale, Carmine, Picillo, Marina, Cuoco, Sofia, Moccia, Marcello, Pezzella, Domenica, Erro, Roberto, Longo, Katia, Vicidomini, Caterina, Pellecchia, Maria Teresa, Amboni, Marianna, Brunetti, Arturo, Salvatore, Marco, Barone, Paolo, Pappatà, Sabina
• Format: Article
• Language: English
• Subjects: Aged; Apathy; Apathy - physiology; Behavioral disorders; Cohort Studies; Corpus Striatum - diagnostic imaging; Corpus Striatum - metabolism; Dopamine; Dopamine Plasma Membrane Transport Proteins - metabolism; Female; FP-CIT SPECT; Humans; Male; Middle Aged; Neurology; Non-motor symptoms; Parkinson Disease - diagnostic imaging; Parkinson Disease - metabolism; Parkinson's disease; Retrospective Studies; Tomography, Emission-Computed, Single-Photon - methods
• ISSN: 1353-8020; 1873-5126
• DOI: 10.1016/j.parkreldis.2015.02.015

Abstract Introduction Apathy is a neuropsychiatric symptom in Parkinson's Disease (PD) which has a negative impact on quality of life and might be related in part to damage of presynaptic dopaminergic system. Little is known about relationship between striatal dopamine levels and apathy in PD patients without dementia and/or depression. The aim of the present study was to investigate the relationship between “pure apathy” and striatal dopamine uptake in untreated, drug-naïve PD patients without clinically significant dementia and/or depression. Methods Fourteen PD patients with pure apathy and 14 PD patients without apathy, matched for age, side of motor symptoms at onset, motor disability and disease duration, underwent both neuropsychological and behavioral examination including self-rated version of the Apathy Evaluation Scale (AES-S). All patients underwent 123 I-FP-CIT (DaT-SCAN) SPECT to assess dopamine transporter (DAT) striatal uptake. Results PD patients with apathy showed lower DAT levels in the striatum than non-apathetic patients. After Bonferroni correction the difference between groups was significant in the right caudate. Conclusions Apathy is associated with reduced striatal dopamine transporter levels, independent of motor disability and depression in non-demented PD patients. These findings suggest that dysfunction of dopaminergic innervation in the striatum and particularly in the right caudate may contribute to development of apathy in early PD.