Cohort study of the association of genetic predisposition to excess body weight with survival in women diagnosed with breast cancer

Excess body weight, which is associated with poor survival after breast cancer (BC) diagnosis, is a heritable trait. The association of genetic predisposition to excess body weight and risk of mortality among BC survivors is not clear. A cohort study using data from the Cancer Prevention Study-II Nutrition Cohort investigated this association. In this study of 4177 postmenopausal-BC survivors with genetic data, those with a polygenic score for body mass index (BMI-PGS) in the top tertile had a 15% higher mortality risk compared with those in the bottom tertile of the score. A greater number of hours of walking per week was needed to mitigate the inherited susceptibility. The authors conclude that these results suggest that genetic predisposition to excess body weight is associated with increased risk of mortality among BC survivors, and personalized lifestyle recommendation that incorporate genetic predisposition should be considered.