Abstract
Background: Researchers commonly use job-exposure matrices (JEMs) and self-reports to characterize occupational exposures in epidemiologic studies of respiratory diseases. JEMs provide more objective assessments than self-reports, but the latter are easy to collect and have performed well in some studies. We investigated whether one of these exposure estimates had a stronger association with severe exacerbation of asthma in a study of adults with asthma.
Methods: We used data from a telephone survey of 557 working adults with asthma in the eastern United States. Severe exacerbation was defined as having had at least 2 events with unplanned care or hospitalization for asthma in the 12 months before interview, and occupational exposure was determined for the same time period using both a recently-developed asthma-specific JEM and self-reports of being exposed to dust, smoke, gas, or chemical fumes at work. We used regression to model severe exacerbation and examine exposure-exacerbation relationships while controlling for potential confounders.
Results: Occupational exposure was assessed as present for 254 using the JEM and 334 by self-reports, and the two groups overlapped by 175. Twenty-seven percent (n=150) fulfilled the criteria for severe exacerbation. The contrast in frequency of severe exacerbation for exposed versus unexposed was greater with the JEM (31% vs 23%, p=0.05) than self-reports (28% vs 25%, p=0.57), and this difference persisted after controlling for sex and education.
Conclusion: Occupational exposures assessed using a JEM had a stronger association with severe exacerbation of asthma than self-reported exposures.
- © 2014 ERS