title: Lower CSF interleukin-6 predicts future depression in a population-based sample of older women followed for 17 years.
abstract: OBJECTIVE
  The literature regarding cerebrospinal fluid (CSF) cytokines in geriatric depression is sparse. The aim of this study was to examine associations between CSF interleukin-6 (IL-6) and related proinflammatory cytokines and current and future depression in a population-based sample of older women who were followed for 17 years.
  
  
  METHODS
  83 non-demented women aged 70-84 years who participated in the Prospective Population Study of Women in Gothenburg, Sweden took part in a lumbar puncture in 1992-3. CSF- IL-6, interleukin-1β (IL-1β), interleukin- 8 (IL-8) and tumor necrosis factor-α (TNF-α) were measured. Psychiatric symptoms were rated with the Comprehensive Psychopathological Rating Scale at baseline and at three subsequent face-to-face examinations. Depression (major or minor) was diagnosed in accordance with DSM-IV/DSM-IV research criteria.
  
  
  RESULTS
  At baseline, women with ongoing depression had lower levels of IL-6 (p<0.04), IL-8 (p<0.05) and TNF-α (p<0.05) compared with those without depression. In women without depression at baseline, lower CSF IL-6 levels predicted depression at one or more follow-up examination (p<0.03). Results from the generalized linear mixed logistic model using all baseline and follow-up data on depression status and Mini Mental State Examination score showed a significant relationship between IL-6 and depression (p=0.005 OR 0.370 CI [0.184-0.744]).
  
  
  CONCLUSIONS
  Lower levels of CSF IL-6 were associated with current depression and with future depression during a follow-up of almost two decades. Our findings suggest that lower levels of CSF IL-6 may be related to depression vulnerability in later life.
authors.affiliation: Neuropsychiatric Epidemiology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at The University of Gothenburg, Gothenburg, Sweden. silke.kern@vgregion.se
authors.forename: Silke
authors.initials: S
authors.lastname: Kern
authors.forename: Ingmar
authors.initials: I
authors.lastname: Skoog
authors.forename: Anne
authors.initials: A
authors.lastname: Börjesson-Hanson
authors.forename: Kaj
authors.initials: K
authors.lastname: Blennow
authors.forename: Henrik
authors.initials: H
authors.lastname: Zetterberg
authors.forename: Svante
authors.initials: S
authors.lastname: Östling
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kern
authors.forename: Pia
authors.initials: P
authors.lastname: Gudmundsson
authors.forename: Thomas
authors.initials: T
authors.lastname: Marlow
authors.forename: Lars
authors.initials: L
authors.lastname: Rosengren
authors.forename: Margda
authors.initials: M
authors.lastname: Waern
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016207:Cytokines / Q000134:cerebrospinal fluid; D003627:Data Interpretation, Statistical; D003863:Depression / Q000134:cerebrospinal fluid* / Q000523:psychology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000134:cerebrospinal fluid*; D016015:Logistic Models; D008137:Longitudinal Studies; D011153:Population; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D014409:Tumor Necrosis Factor-alpha / Q000134:cerebrospinal fluid
chemical_list: D016207:Cytokines; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha