Eating Disorders and Breast Cancer
Menée aux Etats-Unis à partir de données portant sur 47 813 participantes âgées de 35 à 74 ans, cette étude de cohorte prospective évalue l'association entre des troubles du comportement alimentaire et le risque de cancer du sein (durée médiane de suivi : 5,4 ans)
Background: Eating disorders such as anorexia nervosa and bulimia nervosa affect overall and reproductive health and may also affect breast cancer risk. We studied the association between self-reported eating disorders and breast cancer risk in a prospective cohort study. Methods: In 2003–2009, the Sister Study enrolled women ages 35–74 years who had a sister with breast cancer but had never had it themselves. Using data from 47,813 women, we estimated adjusted HRs and 95% confidence intervals (CI) for the association between eating disorders and invasive breast cancer over a median of 5.4 years of follow-up. Results: Three percent (n = 1,569) of participants reported a history of an eating disorder. Compared with women who never had an eating disorder, women who reported eating disorders in the past had reduced breast cancer risk (HR = 0.62; 95% CI, 0.42–0.92). Conclusions: In this large prospective, observational cohort study, we observed an inverse association between having a history of an eating disorder and invasive breast cancer. Impact: Historical eating disorders may be associated with a long-term reduction in breast cancer risk.