The French E3N Prospective Cohort Study

The French E3N cohort was initiated in 1990 to investigate the risk factors associated with cancer and other major non-communicable diseases in women.
The participants were insured through a national health system that primarily covered teachers, and were enrolled from 1990 after returning baseline self-administered questionnaires and providing informed consent. The cohort comprised nearly 100 000 women with baseline ages ranging from 40 to 65 years.
Follow-up questionnaires were sent approximately every 2-3 years after the baseline and addressed general and lifestyle characteristics together with medical events (cancer, cardiovascular diseases, diabetes, depression, fractures and asthma, among others). The follow-up questionnaire response rate remained stable at approximately 80%.
A biological material bank was generated and included blood samples collected from 25 000 women and saliva samples from an additional 47 000 women.
Ageing among the E3N cohort provided the opportunity to investigate factors related to agerelated diseases and conditions as well as disease survival.