title: Beta-amyloid deposition and cognitive function in patients with major depressive disorder with different subtypes of mild cognitive impairment: (18)F-florbetapir (AV-45/Amyvid) PET study.
abstract: OBJECTIVE
  The objective of this study was to evaluate the amyloid burden, as assessed by (18)F-florbetapir (AV-45/Amyvid) positron emission tomography PET, in patients with major depressive disorder (MDD) with different subtypes of mild cognitive impairment (MCI) and the relationship between amyloid burden and cognition in MDD patients.
  
  
  METHODS
  The study included 55 MDD patients without dementia and 21 healthy control subjects (HCs) who were assessed using a comprehensive cognitive test battery and (18)F-florbetapir PET imaging. The standardized uptake value ratios (SUVR) in eight cortical regions using the whole cerebellum as reference region were determined and voxel-wise comparisons between the HC and MDD groups were performed. Vascular risk factors, serum homocysteine level and the apolipoprotein E (ApoE) genotype were also determined.
  
  
  RESULTS
  Among the 55 MDD patients, 22 (40.0 %) had MCI, 12 (21.8 %) non-amnestic MCI (naMCI) and 10 (18.2 %) amnestic MCI (aMCI). The MDD patients with aMCI had the highest relative (18)F-florbetapir uptake in all cortical regions, and a significant difference in relative (18)F-florbetapir uptake was found in the parietal region as compared with that in naMCI subjects (P < 0.05) and HCs (P < 0.01). Voxel-wise analyses revealed significantly increased relative (18)F-florbetapir uptake in the MDD patients with aMCI and naMCI in the frontal, parietal, temporal and occipital areas (P < 0.005). The global cortical SUVR was significantly negatively correlated with MMSE score (r = -0.342, P = 0.010) and memory function (r = -0.328, P = 0.015). The negative correlation between the global SUVR and memory in the MDD patients remained significant in multiple regression analyses that included age, educational level, ApoE genotype, and depression severity (β = -3.607, t = -2.874, P = 0.006).
  
  
  CONCLUSIONS
  We found preliminary evidence of brain beta-amyloid deposition in MDD patients with different subtypes of MCI. Our findings in MDD patients support the hypothesis that a higher amyloid burden is associated with a poorer memory performance. We also observed a high prevalence of MCI among elderly depressed patients, and depressed patients with MCI exhibited heterogeneously elevated (18)F-florbetapir retention as compared with depressed patients without MCI. The higher amyloid burden in the aMCI patients suggests that these patients may also be more likely to develop Alzheimer's disease than other patients diagnosed with major depression.
authors.affiliation: Department of Psychiatry, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Kuan-Yi
authors.initials: KY
authors.lastname: Wu
authors.affiliation: Department of Psychiatry, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Chia-Yih
authors.initials: CY
authors.lastname: Liu
authors.affiliation: Department of Psychiatry, Kaohsiung Medical University Hospital and College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Cheng-Sheng
authors.initials: CS
authors.lastname: Chen
authors.affiliation: Department of Psychiatry, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Chia-Hsiang
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, 5. Fu-Hsing Street, Kuei Shan Hsiang, Taoyuan, Taiwan.|Department of Medical Imaging and Radiological Sciences and Healthy Aging Research Center, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Ing-Tsung
authors.initials: IT
authors.lastname: Hsiao
authors.affiliation: Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, 5. Fu-Hsing Street, Kuei Shan Hsiang, Taoyuan, Taiwan.|Department of Medical Imaging and Radiological Sciences and Healthy Aging Research Center, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Chia-Ju
authors.initials: CJ
authors.lastname: Hsieh
authors.affiliation: Department of Psychiatry, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Chin-Pang
authors.initials: CP
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, 5. Fu-Hsing Street, Kuei Shan Hsiang, Taoyuan, Taiwan.|Department of Medical Imaging and Radiological Sciences and Healthy Aging Research Center, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Tzu-Chen
authors.initials: TC
authors.lastname: Yen
authors.affiliation: Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, 5. Fu-Hsing Street, Kuei Shan Hsiang, Taoyuan, Taiwan. lin4857@adm.cgmh.org.tw.|Department of Medical Imaging and Radiological Sciences and Healthy Aging Research Center, Chang Gung University, Tao-Yuan, Taiwan. lin4857@adm.cgmh.org.tw.
authors.forename: Kun-Ju
authors.initials: KJ
authors.lastname: Lin
mesh_terms: D016229:Amyloid beta-Peptides / Q000378:metabolism*; D000814:Aniline Compounds; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism; D003071:Cognition; D060825:Cognitive Dysfunction / Q000150:complications*; D003865:Major Depressive Disorder / Q000150:complications / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology*; D005026:Ethylene Glycols; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography
chemical_list: D016229:Amyloid beta-Peptides; D000814:Aniline Compounds; D005026:Ethylene Glycols; C545186:florbetapir
keywords: 18F-Florbetapir (AV-45/Amyvid); Alzheimer’s disease; Amyloid; Dementia; Major depressive disorder; Mild cognitive impairment