[18F] AV-45 PET amyloid binding imaging for non-demented patients with late-life depression--The 2nd-to-3rd year study of a 3-year term project

Some systematic review and meta-analysis studies had revealed that a life-time history of depression may confer an increased risk for later developing Alzheimer disease (AD). Depression reflects an independent risk factor for AD. Amyloid senile plaques are neuropathologic hallmarks of Alzheimer disease, which may be associated with mood and anxiety symptoms years before mild cognitive impairment (MCI) and AD diagnosis. Besides, A large body of literature has suggested higher rates and severity of white matter hyperintensities in elderly depressed patients relative to age-matched comparison subjects. Specific brain regions were found greater white matter hyperintensities located in specific neuron tracts associated with cognitive and emotional function. The role of white matter hyperintensities, that may imply one of common etiologies of AD and late-life depession, remains poorly understood. This study will focus on elderly non-demented and non-MCI patients with late-life major depression. Depressed patients (N=50) and nondepressed comparison subjects (N=25) age 55 years or older were recruited. Depressed patients were evaluated for the presence of DSM-IV major depression. To address this issue, this study will obtain positron emission tomography (PET) scans of [18F] AV-45 to determine whether late-life major depression in nondemented subjects were associated with increased [18F] AV-45 binding values, to identify characteristic patterns of brain regions of [18F] AV-45 binding in patients with late-life depression and to verify the hypothesis that depression is one of the independent risk factors of AD. Magnetic resonance imaging (MRI) will be conducted for each subject in order to provide a structural reference for the PET images and a quantitative analyses of Page 2 of 2 white matter hyperintensities. ApoE genotyping will be considered as one of the covariates but not for genetic study in this study. The preliminary results from the analyses of recruited subjects from Aug 2011 to Nov 2011 were presented in the contents of this research project.

Project ID:PC10202-0563
External Project ID:NSC101-2314-B182-054-MY2