Obesity and the Effects of Weight Reduction: A Spotlight on Women with Hormone Receptor-Positive Breast Cancer and Heart Disease

Obesity is a common overlapping risk factor for cancer and cardiovascular disease (CVD), and the long-term consequences of these chronic, interconnected diseases are severe. The importance of CVD in breast cancer (BC) patients and survivors has been well-established, and the potential impact of some BC treatments (such as cardiotoxic effects related to chemotherapy or targeted therapy with the use of doxorubicin or trastuzumab, and radiation therapy, especially in cases of left breast tumours) on the cardiovascular condition necessitates ongoing cardiological surveillance. In addition, the possible reduction of some underlying risk factors is critical to long-term protection of BC patients and survivors. The concept of obesity dynamically interacting with both BC and CVD is important because it is a modifiable risk factor, and the modern management of obesity deserves emphasis. In particular, for many BC patients and survivors, an effective weight reduction programme integrated with standard anticancer and cardiology therapies can improve patient outcomes. This review presents the complex relationships between overweight, obesity, CVD, and BC risk and highlights outcomes in post and premenopausal women, focussing on patients with hormone receptor-positive BC. The review provides evidence from epidemiologic, observational, and weight loss intervention trials which have examined the effects of weight reduction programmes on BC outcomes. Such studies have indicated that moderate weight loss, with regular physical exercises or stress reduction, can significantly improve BC outcomes. Future lifestyle intervention trials could support the incorporation of weight loss interventions as an integral element of comprehensive management for BC patients and survivors.