title: Progressive decrease of N-acetylaspartate to total creatine ratio in the pregenual anterior cingulate cortex in patients with major depressive disorder: longitudinal 1H-MR spectroscopy study.
abstract: BACKGROUND
  Longitudinal metabolic changes of total choline (tCho), creatine+phosphocreatine (total creatine, tCr), and N-acetylaspartate (NAA) in the pregenual anterior cingulate cortex (pACC) of patients with major depressive disorder (MDD) have not been well evaluated.
  
  
  OBJECTIVE
  To evaluate the longitudinal changes of the metabolic levels of tCho, tCr, and NAA in the pACC of MDD patients and normal controls with the use of Single-voxel (1)HMRS.
  
  
  METHODS
  Single-voxel (1)HMRS was acquired in the pACC of 21 female patients with MDD and 26 age- and gender-matched controls. Follow-up scans were acquired in 10 patients with MDD and 15 controls after 9-10 months from baseline scans. Absolute concentrations of tCho, tCr, and NAA, and the ratios of NAA/tCr and tCho/tCr were calculated and compared between and within groups.
  
  
  RESULTS
  The patient group showed slightly improved clinical symptoms, as measured by Beck's Depression Inventory (P=0.035), after treatment with antidepressants. Comparison of baseline scans between the groups showed no differences in any of the absolute metabolite concentrations or ratios. The NAA/tCr ratio in the pACC of patients with MDD showed a significant decrease in the follow-up scan (P=0.032), and the NAA/tCr ratio of the baseline scan showed logarithmic negative association with illness duration (P=0.024).
  
  
  CONCLUSIONS
  A progressive decrease in the NAA/tCr ratio in the pACC of patients with MDD was demonstrated and the decrease in this ratio was at the highest rate in the early period after illness onset. These findings indicate the neuronal degeneration and dysfunction of the pACC, and the importance of early clinical intervention in female patients with MDD.
authors.affiliation: Neuroscience Research Institute, Kangwon National University Hospital, Kangwon-do, Republic of Korea.
authors.forename: Woo Suk
authors.initials: WS
authors.lastname: Tae
authors.affiliation: Neuroscience Research Institute, Kangwon National University Hospital, Kangwon-do, Republic of Korea Engineering Research Center For Bioreaction To Reactive Oxygen Species, School of Medicine, Kyung Hee University, Seoul, Republic of Korea samskim@kangwon.ac.kr.
authors.forename: Sam Soo
authors.initials: SS
authors.lastname: Kim
authors.affiliation: Neuroscience Research Institute, Kangwon National University Hospital, Kangwon-do, Republic of Korea.
authors.forename: Kang Uk
authors.initials: KU
authors.lastname: Lee
authors.affiliation: Neuroscience Research Institute, Kangwon National University Hospital, Kangwon-do, Republic of Korea.
authors.forename: Eui-Cheol
authors.initials: EC
authors.lastname: Nam
authors.affiliation: Neuroscience Research Institute, Kangwon National University Hospital, Kangwon-do, Republic of Korea.
authors.forename: Sung Hye
authors.initials: SH
authors.lastname: Koh
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D016022:Case-Control Studies; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003865:Major Depressive Disorder / Q000188:drug therapy / Q000378:metabolism*; D005260:Female; D006179:Gyrus Cinguli / Q000378:metabolism*; D006801:Humans; D008137:Longitudinal Studies; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D010725:Phosphocreatine / Q000378:metabolism
chemical_list: D000928:Antidepressive Agents; D010725:Phosphocreatine; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline
keywords: MR spectroscopy; N-acetyl aspartate; anterior cingulate cortex; longitudinal study; major depressive disorder