title: The role of IL-8 in patients with fibromyalgia: a prospective longitudinal study of 6 months.
abstract: OBJECTIVE
  In this prospective longitudinal clinical study, we evaluated the role of proinflammatory cytokine IL-8 and its clinical relevance in patients with fibromyalgia (FM) who fulfilled clearly defined inclusion and exclusion criteria and underwent a 3-week inpatients multidisciplinary pain therapy.
  
  
  METHODS
  IL-8 in sera was measured in 20 patients with FM and 80 healthy participants at 4 fixed time points: at the beginning of the study, at 10 days, 21 days, and 6 months, respectively. Pain intensity, back function, depression, nicotine/alcohol consumption, and medication were assessed in the patient group and correlated with IL-8 levels.
  
  
  RESULTS
  Before and during the inpatient therapy, the serum level of IL-8 was significantly higher in patients with FM compared with controls (P<0.001), but did not correlated with pain intensity and medication. Already at T1 there was a significant reduction of IL-8 serum level (P=0.023) in patient group. Six months after multidisciplinary pain therapy, IL-8 serum level in FM patients was still significantly higher than controls (P=0.044) but reduced approximately to normal range and correlated significantly negatively with pain intensity (r=-0.782, P=0.001). Patients with FM had significantly less pain (P<0.001) and better back function (P<0.001) at day 2 than at day 0. In addition, in patients with FM, IL-8 serum level correlated with nicotine consumption (r=0.471, P=0.042).
  
  
  CONCLUSIONS
  Our results suggest that IL-8 level contributes in patients with FM whose pain intensity and back function can be improved under influence of multidisciplinary pain therapy without need of an anti-IL-8 therapy.
authors.affiliation: Department of Orthopedic Surgery, Ruprecht-Karls-University of Heidelberg, Heidelberg, Germany. haili.wang@ok.uni-heidelberg.de
authors.forename: Haili
authors.initials: H
authors.lastname: Wang
authors.forename: Matthias
authors.initials: M
authors.lastname: Buchner
authors.forename: Michael T
authors.initials: MT
authors.lastname: Moser
authors.forename: Volker
authors.initials: V
authors.lastname: Daniel
authors.forename: Marcus
authors.initials: M
authors.lastname: Schiltenwolf
mesh_terms: D000375:Aging / Q000502:physiology; D000428:Alcohol Drinking / Q000523:psychology; D001415:Back / Q000503:physiopathology; D015415:Biomarkers; D015992:Body Mass Index; D003131:Combined Modality Therapy; D003863:Depression / Q000523:psychology; D005260:Female; D005356:Fibromyalgia / Q000097:blood* / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D016209:Interleukin-8 / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy / Q000209:etiology; D010147:Pain Measurement; D011446:Prospective Studies; D012727:Sex Characteristics; D011795:Surveys and Questionnaires; D014029:Tobacco Use Disorder / Q000523:psychology; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D016209:Interleukin-8