Objective: The goal of this study is to evaluate brain metabolism in mild cognitive impairment (MCI) patients with and without apathy (as determined by the Neuropsychiatric Inventory Questionnaire).
Methods: Baseline data from 65 MCI participants (11 with apathy and 54 without) from the Alzheimer's Disease (AD) Neuroimaging Initiative study were analyzed. All participants underwent a comprehensive cognitive and neuropsychiatric assessment, volumetric MRI and measures of cerebral glucose metabolism applying (18)F-fluorodeoxyglucose positron emission tomography at baseline. The presence of apathy at baseline was determined by the Neuropsychiatric Inventory Questionnaire.
Results: There was no difference between apathy and apathy-free MCI patients regarding cognitive assessment and neuropsychiatric measures when apathy-specific items were removed. Cerebrovascular disease load and cerebral atrophy were equivalent in both groups. Compared with the apathy-free MCI patients, MCI patients with apathy had significantly decreased metabolism in the posterior cingulate cortex.
Conclusion: The presence of apathy in MCI patients is associated with AD-specific pattern of brain metabolic defect. These results could suggest that apathy belongs to the spectrum of prodromal AD symptoms.
Keywords: Alzheimer's disease; Alzheimer's disease neuroimaging initiative (ADNI); FDG-PET; apathy; biomarker; mild cognitive impairment.
Copyright © 2014 John Wiley & Sons, Ltd.