Programmed health surveillance and detection of emerging diseases in occupational health: contribution of the French national occupational disease surveillance and prevention network (RNV3P).

Objective: The French national occupational disease surveillance and prevention network (RNV3P) includes the 30 occupational disease consultation centres in university hospitals to which patients are referred for potentially work-related diseases, and an occupational health service. The aim of this work is to demonstrate the contribution of RNV3P to national health surveillance.

Methods: Data from consultations are recorded in standardised occupational health reports and coded using international or national classifications. Programmed health surveillance is carried out through annual follow-up of annual referrals to experts for pre-selected disease-exposure associations, as well as incidence estimations for the well characterised working population followed by the occupational health service. Hypotheses on new emerging diseases are generated using statistical methods employed in pharmacosurveillance and by modelling as an exposome to analyse multiple exposures.

Results: 58,777 occupational health reports were collected and analysed from 2001 to 2007. Referrals to the 30 university hospital centres increased significantly for asbestos-related diseases, mood disorders and adjustment disorders related to psychological and organisational demands, and for elbow and shoulder disorders related to manual handling. Referrals significantly decreased for asthma and for rhinitis related to exposure to organic dusts (vegetable or animal) or chemicals, except for cosmetics and cleaning products. Estimation of incidences by the occupational health services showed different patterns in different sectors of activity. The methods for detecting emerging diseases are presented and illustrated using the example of systemic sclerosis, identifying new exposures and new sectors of activity to be investigated.

Conclusion: The RNV3P collects data from two complementary samples: 30 university hospital centres (workers or former workers) and an occupational health service (current workers). This dual approach is useful for surveillance and for hypothesis generation on new emerging disease-exposure associations.