0155 Use of a prediction model of asthma with antiasthma drug claims for epidemiological surveillance of asthma in self-employed workers in France

Objectives To estimate prevalence and risk of current asthma among affiliates to the health insurance for self-employed workers according to economic activities. Method We defined current asthma using a prediction model developed in a study conducted in 2006 among workers aged between 18 to 65, affiliated to the Régime Social des Indépendants (RSI) in three French regions. The model used as predictors antiasthma drug claims data and the prescriber’s medical speciality. In 2013, we obtained from the RSI, economic sectors and drug claims data of all French affiliates on whom we applied our prediction model. We used logistic regression to estimate asthma risk of each economic sector versus all the others. Results The population comprised 967391 workers. In men, the asthma prevalence was 5.6%. Elevated odds-ratios were observed in the production of food products (OR=1.70 [95% CI 1.63–1.78]), recycling (OR=1.44 [95% CI 1.23–1.70]), health and social work (OR=1.34 [95% CI 1.16–1.54]) and land transport (OR=1.08 [95% CI 1.03–1.13]). In women, the asthma prevalence was 7%. High odds-ratios were observed in education (OR=1.27 [95% CI 1.08–1.50]), manufacture of medical and precision instruments (OR=1.25 [95% CI 0.99–1.58]), land transport (OR=1.11 [95% CI 0.98–1.25]) and hotel/restaurants (OR=1.10 [95% CI 1.05–1.15]). Conclusions Prevalence estimated by the model was close to that observed among self-employed workers within a national survey conducted in 2003. Elevated risks were observed in several industries known to be at risk but also in those not expected. Prediction model approach will allow asthma surveillance in workers without interview with health insurance organisation data when occupational data are available.