Mechanisms underlying the effect of adiposity on risk of post-menopausal oestrogen receptor-positive breast cancer: an interventional mediation analysis

Abstract

BACKGROUND: Adiposity increases the risk of post-menopausal oestrogen receptor (ER)-positive breast cancer. Inflammation, insulin, and insulin-like growth factors and sex-steroid hormones may explain this effect. We performed interventional mediation analysis to estimate the effects of hypothetical interventions targeting these pathways in females with obesity on reducing their excess risk of post-menopausal ER-positive breast cancer relative to females with normal weight. METHODS: The mediation analysis included 1260 post-menopausal females (352 with ER-positive breast cancer) from a case-cohort within the Melbourne Collaborative Cohort Study. A Monte Carlo g-computation approach with non-p..