L’observatoire national des asthmes professionnels

Abstract

L'Observatoire National des Asthmes Professionnels (ONAP) was created in 1996 by two French professionals societies to estimate the incidence of occupational asthma. Occupational and chest physicians were asked to report newly diagnosed cases of work-related asthma and reactive airway dysfunction syndrome (RADS). The information collected included age, sex, occupation, suspected causal agents and diagnostic methods. In 1997, 82.3% of 559 cases reported (64.2% men, mean age 36 years ± 13) involved occupational asthma, 4.7% involved RADS, and 12.7% atypical asthma syndromes. Incidence rates showed a regional variation that ranged from 4 to 73 cases per million workers, with a national mean of 25.7. The most frequently suspected agents were flour (23.3%), followed by isocyanates (16.6%), latex (7.5%), aldehydes (5.5%), and persulfates (4.1%). Occupations at risk were bakers (23.9%), healthcare workers (12%), painters (9.1%), hairdressers (5.2%), wood industry workers (4.8%) and cleaners (3.5%). From 1996 to 1999, 2178 cases were reported to ONAP. The mean annual rate was 24 cases/million of workers (27 cases/million for men, and 19 cases/million for women). Over those 4 years, the rate of occurrence of the most frequently suspected agents remained constant: flour (20.3%), isocyanate (14.1%), latex (7.2%), aldehydes (5.9%) and persulfates (5.8%). We discuss these results and compare them to those reported by similar registries set up elsewhere. Because of the considerable bias inherent in a surveillance system based on voluntary reporting, the reported incidence of occupational asthma is probably lower than the true incidence. However, the number of cases of occupational asthma reported to ONAP was approximately twice the number of cases who were compensated during the same period. The year-to-year reproducibility of these results confirms the relevance of the ONAP program and provides an estimate of the incidence and aetiology of occupational asthma in France.