title: Prevalence of claims-based recurrent low back pain in a Canadian population: a secondary analysis of an administrative database.
abstract: BACKGROUND
  There is a vast literature reporting that the point prevalence of low back pain (LBP) is high and increasing. It is also known that a large proportion of acute LBP episodes are recurrent within 12 months. However, few studies report the annual trends in the prevalence of recurrent LBP or describe these trends according to age and sex categories.
  
  
  METHODS
  We conducted a retrospective cohort study involving 401 264 adults selected from the administrative database of physician claims for the province of Quebec, Canada. These adults, aged 18 years and over, met the criteria of having consulted a physician three times within a 365-day period between 2000 and 2007 for a LBP condition corresponding to ICD-9 codes 721, 722, 724 or 739. All data were analyzed by sex and clustered according to specific age categories.
  
  
  RESULTS
  We observed a decrease from 1.64% to 1.33% in the annual prevalence between 2000 and 2007 for men. This decrease in prevalence was mostly observed between 35 and 59 years of age. Older (≥ 65 years) women were 1.35 times more at risk to consult a physician for LBP in a recurrent manner than older men. The most frequently reported diagnosis was non-specific LBP between 2000 to 2007. During the same period, sequelae of previous back surgery and spinal stenosis were the categories with the largest increases.
  
  
  CONCLUSIONS
  The annual prevalence of claims-based recurrent LBP progressively decreased between 2000 and 2007 for younger adults (<65 years) while older adults (≥ 65 years) showed an increase. Given the aging Canadian population, recurrent low back pain could have an increasing impact on the quality of life of the elderly as well as on the healthcare system.
authors.affiliation: The PRIMUS Group, Clinical Research Centre Etienne-Lebel, CHUS, Sherbrooke, Quebec, Canada.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Beaudet
authors.forename: Josiane
authors.initials: J
authors.lastname: Courteau
authors.forename: Philippe
authors.initials: P
authors.lastname: Sarret
authors.forename: Alain
authors.initials: A
authors.lastname: Vanasse
mesh_terms: D000328:Adult; D002170:Canada / Q000453:epidemiology; D015331:Cohort Studies; D016208:Databases, Factual / Q000639:trends*; D005260:Female; D006801:Humans; D007345:Insurance Claim Review / Q000639:trends*; D038801:International Classification of Diseases / Q000639:trends*; D017116:Low Back Pain / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011792:Quebec / Q000453:epidemiology; D012189:Retrospective Studies