title: Association between baseline IL-6 and 1-year recovery in lumbar radicular pain.
abstract: BACKGROUND
  In the present study, the influence of cytokines on 1-year recovery in lumbar radicular pain was examined.
  
  
  METHODS
  In total, 110 patients with symptomatic lumbar disc herniation were followed for 1 year. Uni- and multivariate linear regression was used to assess the influence of interleukin (IL)-6, IL-8, disc degeneration and endplate changes (Modic changes) on the changes in the Oswestry Disability Index (ODI change; primary outcome) and visual analogue scale (VAS) for low back pain (LBP) and leg pain (secondary outcomes).
  
  
  RESULTS
  Less favourable ODI outcome correlated with higher serum IL-6 levels (B = -3.41, 95% CI -5.52 to -1.30, p = 0.002), non-surgical treatment (B = -7.03, 95% CI 1.21 to 12.84, p = 0.018), higher baseline back pain intensity (B = -2.28, 95% CI -3.21 to -1.35, p < 0.001) and low educational level (B = -5.57, 95% CI 0.66 to 10.47, p = 0.027). High VAS for LBP and leg pain at 1 year was associated with high levels of serum IL-6, higher back pain intensity and longer duration of lumbar radicular pain at baseline.
  
  
  CONCLUSIONS
  High serum IL-6 levels, but not disc degeneration or Modic changes, were associated with less favourable recovery in patients with lumbar radicular pain. Intense initial back pain, non-surgical treatment, lower educational level and longer duration of radicular pain before treatment also correlated with a slower recovery the first year after disc herniation.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Oslo University Hospital, Ulleval, Norway; Faculty of Medicine, University of Oslo, Norway.
authors.forename: E I
authors.initials: EI
authors.lastname: Schistad
authors.forename: A
authors.initials: A
authors.lastname: Espeland
authors.forename: L M
authors.initials: LM
authors.lastname: Pedersen
authors.forename: L
authors.initials: L
authors.lastname: Sandvik
authors.forename: J
authors.initials: J
authors.lastname: Gjerstad
authors.forename: C
authors.initials: C
authors.lastname: Røe
mesh_terms: D000328:Adult; D015331:Cohort Studies; D004522:Educational Status; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000276:immunology*; D016209:Interleukin-8 / Q000276:immunology*; D055959:Intervertebral Disc Degeneration / Q000473:pathology; D007405:Intervertebral Disc Displacement / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D016014:Linear Models; D017116:Low Back Pain / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures; D026741:Physical Therapy Modalities; D011379:Prognosis; D011446:Prospective Studies; D011843:Radiculopathy / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D061665:Time-to-Treatment; D016896:Treatment Outcome
chemical_list: C508606:CXCL8 protein, human; C508600:IL6 protein, human; D015850:Interleukin-6; D016209:Interleukin-8