title: Asthma caused by occupational exposures is common - a systematic analysis of estimates of the population-attributable fraction.
abstract: BACKGROUND
  The aim of this paper is to highlight emerging data on occupational attributable risk in asthma. Despite well documented outbreaks of disease and the recognition of numerous specific causal agents, occupational exposures previously had been relegated a fairly minor role relative to other causes of adult onset asthma. In recent years there has been a growing recognition of the potential importance of asthma induced by work-related exposures
  
  
  METHODS
  We searched Pub Med from June 1999 through December 2007. We identified six longitudinal general population-based studies; three case-control studies and eight cross-sectional analyses from seven general population-based samples. For an integrated analysis we added ten estimates prior to 1999 included in a previous review.
  
  
  RESULTS
  The longitudinal studies indicate that 16.3% of all adult-onset asthma is caused by occupational exposures. In an overall synthesis of all included studies the overall median PAR value was 17.6%.
  
  
  CONCLUSIONS
  Clinicians should consider the occupational history when evaluating patients in working age who have asthma. At a societal level, these findings underscore the need for further preventive action to reduce the occupational exposures to asthma-causing agents.
authors.affiliation: Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital, Göteborg, Sweden. kjell.toren@amm.gu.se
authors.forename: Kjell
authors.initials: K
authors.lastname: Torén
authors.forename: Paul D
authors.initials: PD
authors.lastname: Blanc
mesh_terms: D001249:Asthma / Q000453:epidemiology* / Q000209:etiology*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D014943:Global Health; D006279:Health Maintenance Organizations / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D016273:Occupational Exposure / Q000009:adverse effects*; D012307:Risk Factors