title: The association between smoking and low back pain: a meta-analysis.
abstract: OBJECTIVE
  To assess the association between smoking and low back pain with meta-analysis.
  
  
  METHODS
  We conducted a systematic search of the MEDLINE and EMBASE databases until February 2009. Eighty-one studies were reviewed and 40 (27 cross-sectional and 13 cohort) studies were included in the meta-analyses.
  
  
  RESULTS
  In cross-sectional studies, current smoking was associated with increased prevalence of low back pain in the past month (pooled odds ratio [OR] 1.30, 95% confidence interval [CI], 1.16-1.45), low back pain in the past 12 months (OR 1.33, 95% CI, 1.26-1.41), seeking care for low back pain (OR 1.49, 95% CI, 1.38-1.60), chronic low back pain (OR 1.79, 95% CI, 1.27-2.50) and disabling low back pain (OR 2.14, 95% CI, 1.11-4.13). Former smokers had a higher prevalence of low back pain compared with never smokers, but a lower prevalence of low back pain than current smokers. In cohort studies, both former (OR 1.32, 95% CI, 0.99-1.77) and current (OR 1.31, 95% CI, 1.11-1.55) smokers had an increased incidence of low back pain compared with never smokers. The association between current smoking and the incidence of low back pain was stronger in adolescents (OR 1.82, 95% CI, 1.42-2.33) than in adults (OR 1.16, 95% CI, 1.02-1.32).
  
  
  CONCLUSIONS
  Our findings indicate that both current and former smokers have a higher prevalence and incidence of low back pain than never smokers, but the association is fairly modest. The association between current smoking and the incidence of low back pain is stronger in adolescents than in adults.
authors.affiliation: Centre of Expertise for Health and Work Ability, Finnish Institute of Occupational Health, Helsinki, Finland. rahman.shiri@ttl.fi
authors.forename: Rahman
authors.initials: R
authors.lastname: Shiri
authors.forename: Jaro
authors.initials: J
authors.lastname: Karppinen
authors.forename: Päivi
authors.initials: P
authors.lastname: Leino-Arjas
authors.forename: Svetlana
authors.initials: S
authors.lastname: Solovieva
authors.forename: Eira
authors.initials: E
authors.lastname: Viikari-Juntura
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D015331:Cohort Studies; D015897:Comorbidity; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D017116:Low Back Pain / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010147:Pain Measurement; D011379:Prognosis; D018570:Risk Assessment; D012720:Severity of Illness Index; D017678:Sex Distribution; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology*