Background: Asthma is work related when there is an association between symptoms and work. Occupational asthma (OA) is induced by the workplace, whereas work-exacerbated asthma (WEA) is triggered by the workplace but not induced by it.
Objective: We sought to compare the clinical characteristics and the use of medical resources between subjects with work-related asthma (WRA) and asthmatic control subjects without WRA, as well as between subjects with OA and subjects with WEA.
Methods: We performed a retrospective cohort study of the charts of subjects with WRA who were investigated between 2001 and 2004 in our centers. These subjects were matched according to sex, age, and FEV(1) to subjects with non-WRA investigated during the same period. All charts were linked to the information provided by the Régie de l'assurance maladie du Québec, including outpatient clinic visits and visits to the emergency department and hospitalizations during the year before and after the initial assessment in our centers.
Results: Three hundred fifty-one subjects had WRA (WEA, 145; OA, 206), whereas 384 subjects were asthmatic control subjects without WRA. Subjects with WRA had more asthma exacerbations than subjects with non-WRA. The risk factor of experiencing a severe asthma exacerbation was no greater for OA than for WEA (odds ratio, 1.15; 95% CI, 0.75-1.75).
Conclusion: WRA is associated with a larger use of medical resources than non-WRA.
Clinical implications: Improving the diagnosis and management of WRA is crucial for limiting the use of medical resources associated with this condition.