Data linkage to estimate the extent and distribution of occupational disease: new onset adult asthma in Alberta, Canada

Am J Ind Med. 2009 Nov;52(11):831-40. doi: 10.1002/ajim.20753.


Background: Although occupational asthma is a well recognized and preventable disease, the numbers of cases presenting for compensation may be far lower than the true incidence.

Methods: Workers' Compensation Board (WCB) claims for any reason 1995-2004 were linked to physician billing data. New onset adult asthma (NOAA) was defined as a billing for asthma (ICD-9 code of 493) in the 12 months prior to a WCB claim without asthma in the previous 3 years. Incidence was calculated by occupation, industry and, in a case-referent analysis, exposures estimated from an asthma specific job exposure matrix.

Results: There were 782,908 WCB eligible claims, with an incidence rate for NOAA of 1.6%: 23 occupations and 21 industries had a significantly increased risk. Isocyanates (OR 1.54: 95% CI 1.01-2.36) and exposure to mixed agricultural allergens (OR = 1.59: 95% CI 1.17-2.18) were related to NOAA overall, as were exposures to cleaning chemicals in men (OR = 1.91:95% CI 1.34-2.73). Estimates of the number of cases of occupational asthma suggested a range of 4% to about half for the proportion compensated.

Conclusions: Data linkage of administrative records can demonstrate under-reporting of occupational asthma and indicate areas for prevention.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age of Onset
  • Alberta / epidemiology
  • Asthma / epidemiology*
  • Asthma / prevention & control
  • Case-Control Studies
  • Data Collection
  • Female
  • Humans
  • Incidence
  • Male
  • Occupational Diseases / epidemiology*
  • Occupational Diseases / prevention & control
  • Workers' Compensation / statistics & numerical data*