Epidemiological surveillance of lumbar disc surgery in the general population from a French region

Introduction
Disc-related sciatica (DRS) is a significant and costly health problem in the working population.
Two studies were performed:
- a pilot study, to assess the feasibility of a surveillance system for DRS using hospital databases for lumbar disc surgery (LDS) ;
- a regional study, to establish whether there is an association between lumbar disc surgery (LDS) for DRS and occupational characteristics and, if confirmed, to evaluate the contribution of the latter to the occurrence of such disorders.

Methods
Pilot study: A total of 272 inpatients (119 men and 153 women) living in a French area discharged in 2002–2003 from a spine center of a University Hospital following LDS were compared with demographic and occupational data on the population of the same region. Regional study: A total of 3,135 inpatients (1,770 men and 1,371 women) living in the Pays de la Loire region discharged in 2007–2008 from most of spine centers of the region (93% of inpatients in the region). For both studies, medical and occupational histories were gathered using a mailed questionnaire. The age-adjusted relative risks and population attributable fraction of risk (PAF) were calculated in relation to occupations and economic sectors.

Results
Pilot study: Information on employment was available for 75 women and 71 men. The risk of LDS varied according to occupations and industries. PAFs were estimated 30% (12–48) for male blue collar workers and 22% (4–40) for female lower white collar workers. PAFs ranged between 7 and 17% in the economic sectors at higher risk.
Regional study: Data are being captured. Results will be available for the ICOH 2012 Congress.

Discussion
The pilot study showed that this surveillance system of LDS can identify occupations and industries at risk.
The regional study would provide more accurate results.