Paper: Geographic variation of pneumoconioses in British Columbia

Author(s) and Affiliation(s):
Chris McLeod, Centre for Health Services and Policy Research, UBC
Dawn Mooney, Centre for Health Services and Policy Research, UBC
Fan Xu, Centre for Health Services and Policy Research, UBC
Cheryl Peters, School of Environmental Health, UBC
Mieke Koehoorn, School of Population and Public Health, UBC
Paul Demers, School of Environmental Health, UBC
Day/Time: Friday at 13:30
Room: St. Patrick Room, 3rd Floor
Objectives:

To map by census division (CD) and health-service delivery area (HSDA) the cumulative incidence of asbestosis, silicosis, and coal workers’ pneumoconiosis in British Columbia (BC) for the period of 1995 to 2006 and to compare the variation in cumulative incidence with historic patterns of respirable dust exposure.

Methods:

Data on all outpatient and hospital visits between 1995 and 2006 for asbestosis, silicosis, and coal workers’ pneumoconiosis (CWP) were obtained from the BC Ministry of Health. Data on accepted claims was obtained from WorkSafeBC. Data sets were linked by Population Data BC and a case was defined as a person with an accepted compensation claim, any diagnosis in hospital discharge records, or at least two visits in the outpatient records. Individuals with any recorded diagnosis prior to 1995 were excluded. Cases were linked to 32 CDs and 16 HSDAs by postal code in the year an individual met the case definition for the 12 years between 1995 and 2006. Cumulative incidence was calculated using the BC population aged 15 or older in 2006 for men and women. Known historic and current sources of high asbestos, coal and silica exposure were also mapped.

Results:

Cumulative incidence rates varied geographically by twenty-fold for all pneumoconioses. For men, the highest cumulative incidence rate was found for asbestosis in the Kootenay Boundary CD (202/100,000), a region that includes a large aluminum smelter, and the Powell River CD (192/100,000), a region with pulp and paper manufacturing. The highest rates for CWP (34/100,000) and silicosis (61/100,000) were in the East Kootenay CD, a region associated with mining. The lowest rates were generally in coastal regions that did not have a history of industrial exposure. Similar trends were observed among women although they tended to have lower rates.

Conclusions:

The association of geographic variation in the cumulative incidence of pneumoconioses with historic sources of respirable dust exposure provides face validity to the use of administrative medical databases for occupational health disease surveillance. These finding also highlight regions where there should be a focus on case ascertainment, workers' compensation, exposure monitoring related to these diseases.