20,000 Volunteers for Medical Research

GAZEL was set up in 1989 among workers of Électricité de France-Gaz de France (EDF-GDF). It was designed as an “open epidemiologic laboratory” characterized by a broad coverage of health problems and determinants and accessible to the community of researchers. At study inception in 1989, the GAZEL Cohort Study included 20,625 volunteers (15,011 men and 5,614 women) then aged from 35 to 50 years. The data routinely collected cover diverse dimensions and come from different sources: annual self-administered questionnaire (morbidity, lifestyles, life events, etc.); personnel department of EDF-GDF for social, demographic, and occupational characteristics; EDF-GDF special social insurance fund (for sickness absences and cancer and ischemic heart disease registries), occupational medicine (occupational exposure and working conditions), Social Action Fund (healthcare utilization), Health Screening Centres for standardized health examination and the National Death Register (causes of death); a biobank including more than 8,000 blood samples was also set up. Today, more than 40 ancillary projects on diversified themes have been set up in the GAZEL Cohort Study by some 30 French and foreign teams from Denmark, Germany, Belgium, Canada, Great Britain, Sweden, Finland, and USA. Health problems as diverse as migraine, postmenopausal osteoporosis, ischemic heart disease, depression, musculoskeletal diseases, or traffic accidents have been the object of research projects in this cohort. They take into account risk factors that are behavioural, social, psychological, occupational, and medical. A substantial proportion of the research work has focused on the problem of social inequalities in health and their occupational, personal, and social determinants using a life course perspective.