title: Catechol-O-methyltransferase (COMT) gene polymorphisms are associated with baseline disability but not long-term treatment outcome in patients with chronic low back pain.
abstract: OBJECTIVE
  To examine the association between COMT and OPRM1 gene polymorphisms and pain and disability at baseline and long-term follow-up in patients treated for chronic low back pain (LBP).
  
  
  METHODS
  371 of 767 unrelated European patients recruited from four randomised trials underwent genetic analyses at mean 11.4 years follow-up. 274 patients had fusion and 97 had non-operative treatment. Association analyses included disability, pain, five single nucleotide polymorphisms (SNPs) in the COMT gene, and one SNP in the OPRM1 gene. Analyses were adjusted for age, gender, smoking, analgesics and treatment.
  
  
  RESULTS
  Disability at baseline was significantly associated with COMT SNPs rs4818 (p = 0.02), rs6269 (p = 0.007), rs4633 (p = 0.04) rs2075507 (p = 0.009), two haplotypes (p < 0.002), age, gender and smoking (p ≤ 0.002). No significant associations with clinical variables were observed for OPRM1, or for COMT at long-term follow-up.
  
  
  CONCLUSIONS
  Results suggest that genetic factors are partly responsible for the variation in disability levels in patients presenting with chronic LBP being considered for surgery; in contrast, genetics has no influence on the long-term outcome of treatment.
authors.affiliation: Department of Orthopaedics, Oslo University Hospital-Rikshospitalet, Oslo, Norway. dr.ahmad.omair@gmail.com.|Department of Pathology, Shifa College of Medicine, H-8/4, Islamabad, Pakistan. dr.ahmad.omair@gmail.com.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Omair
authors.affiliation: Department of Research and Development, Spine Center Division, Schulthess Klinik, Zurich, Switzerland.
authors.forename: Anne F
authors.initials: AF
authors.lastname: Mannion
authors.affiliation: Norwegian Computing Centre, Blindern, Oslo, Norway.
authors.forename: Marit
authors.initials: M
authors.lastname: Holden
authors.affiliation: Nuffield Orthopaedic Centre, University of Oxford, Oxford, UK.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Fairbank
authors.affiliation: Department of Medical Genetics, University of Oslo and Oslo University Hospital-Ullevål, Oslo, Norway.
authors.forename: Benedicte A
authors.initials: BA
authors.lastname: Lie
authors.affiliation: Spine Center Göteborg, Gothenburg, Sweden.
authors.forename: Olle
authors.initials: O
authors.lastname: Hägg
authors.affiliation: Neuro-ortopedic Center, Länssjukhuset Ryhov, Jönköping, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Fritzell
authors.affiliation: Department of Physical Medicine and Rehabilitation, Oslo University Hospital, University of Oslo, Oslo, Norway.
authors.forename: Jens I
authors.initials: JI
authors.lastname: Brox
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D002908:Chronic Disease; D015331:Cohort Studies; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics; D006801:Humans; D017116:Low Back Pain / Q000453:epidemiology / Q000235:genetics / Q000628:therapy; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D017450:Receptors, Opioid, mu / Q000235:genetics; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: C485764:OPRM1 protein, human; D017450:Receptors, Opioid, mu; D002394:Catechol O-Methyltransferase
keywords: Catechol-O-methyltransferase; Chronic low back pain; Lumbar fusion; Modulation; Pain perception; Single nucleotide polymorphism