title: [Cerebral metabolic changes and chronic back pain: Study taking into consideration clinical and psychological parameters].
abstract: BACKGROUND
  The manifestation of chronic pain and psychological impairments are related to alterations of neurotransmitter metabolism in cerebral pain processing regions, e.g., anterior cingular cortex (ACC), insula. Magnetic resonance spectroscopy ((1)H-MRS) enables in vivo quantification of neurotransmitters in the brain and was applied in this study to examine the hypothesized chronic pain-related imbalance between excitatory (glutamatergic) and inhibitory (GABA-ergic) neurotransmitter turnovers in the brain of patients with nonspecific chronic pain.
  
  
  METHODS
  A total of 19 patients with nonspecific chronic (> 3 months) back pain and 19 age- and gender-matched healthy subjects participated in this study. Glutamate and GABA as well as glutamate/GABA ratios were determined in the ACC and insula using (1)H-MRS. Sociodemographic, psychological, and pain-related features were measured with standardized questionnaires.
  
  
  RESULTS
  There was a strong variance of glutamate/GABA ratios for both patients and healthy subjects with no significant difference between the two groups. Regression analysis revealed certain significant predictors, such as anxiety as causal variable for reduced glutamate and depression and age as predictors for reduced GABA in ACC. In the patient group, intensity of pain was a significant predictor for glutamate and GABA levels in the insula.
  
  
  CONCLUSIONS
  Despite the uniform diagnosis of nonspecific chronic back pain, we observed a strong variance of neurotransmitters in cerebral pain processing regions. It is necessary to include psychological as well as clinical parameters (e.g., intensity of pain or depression) for a proper interpretation of neurotransmitter turnovers.
authors.affiliation: Institut für Psychosoziale Medizin und Psychotherapie, Universitätsklinikum Jena, Friedrich-Schiller-Universität, Stoystr. 3, 07740, Jena, Deutschland. lisa.janetzki@uni-jena.de.
authors.forename: L
authors.initials: L
authors.lastname: Janetzki
authors.affiliation: Medical Physics Group, Institut für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Jena, Friedrich-Schiller-Universität, Jena, Deutschland.
authors.forename: A
authors.initials: A
authors.lastname: Gussew
authors.affiliation: Klinik für Neurologie und Klinische Neurophysiologie, Sophien- und Hufeland-Klinikum, Weimar, Deutschland.
authors.forename: R
authors.initials: R
authors.lastname: Malessa
authors.affiliation: Klinik für Neurologie und Klinische Neurophysiologie, Sophien- und Hufeland-Klinikum, Weimar, Deutschland.
authors.forename: U
authors.initials: U
authors.lastname: Habenicht
authors.affiliation: Medical Physics Group, Institut für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Jena, Friedrich-Schiller-Universität, Jena, Deutschland.
authors.forename: J R
authors.initials: JR
authors.lastname: Reichenbach
authors.affiliation: Institut für Psychosoziale Medizin und Psychotherapie, Universitätsklinikum Jena, Friedrich-Schiller-Universität, Stoystr. 3, 07740, Jena, Deutschland.
authors.forename: B
authors.initials: B
authors.lastname: Strauß
authors.affiliation: Institut für Psychosoziale Medizin und Psychotherapie, Universitätsklinikum Jena, Friedrich-Schiller-Universität, Stoystr. 3, 07740, Jena, Deutschland.
authors.forename: C
authors.initials: C
authors.lastname: Borys
mesh_terms: D001416:Back Pain / Q000503:physiopathology* / Q000523:psychology; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology; D004734:Energy Metabolism / Q000502:physiology*; D018846:Excitatory Amino Acids / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D006179:Gyrus Cinguli / Q000503:physiopathology; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D009433:Neural Inhibition / Q000502:physiology; D018377:Neurotransmitter Agents / Q000378:metabolism*; D012016:Reference Values; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D018846:Excitatory Amino Acids; D018377:Neurotransmitter Agents; D005973:Glutamine; D005680:gamma-Aminobutyric Acid
keywords: Chronic pain; Glutamate; Proton magnetic resonance spectroscopy; Psychological factors; γ-aminobutyric acid