Evaluating the impact of GLP-1 receptor agonists on weight management in patients with breast cancer undergoing endocrine therapy: A comparative analysis.

Abstract

e13063 Background: Obesity has been linked to increased risk of recurrence in postmenopausal patients with history of Hormone Receptor positive + (HR) breast cancer. making weight management very important in this patient population. The use of endocrine therapy with aromatase inhibitor (AI) or selective estrogen modulators (SERM) in this population has been linked to weight gain (PMID: 37831449). This study evaluates the effectiveness of GLP-1 medications (Semaglutide, Liraglutide, Dulaglutide, Tirzepatide) in these patients, comparing weight loss outcomes to those in non-cancer populations. Methods: A retrospective analysis was conducted on breast cancer patients who were receiving endocrine therapy (AI or SERM) in combination with GLP-1 medications. The study primarily focused on evaluating mean baseline Body Mass Index (BMI), the proportion of patients with a BMI ≥30, and the mean percentage change in BMI at the 12-month mark, including 95% confidence intervals (CIs) for these changes. Results: The study found that the mean percentage changes in BMI at 12 months for the GLP-1 medications were as follows: Semaglutide resulted in a -4.34% change (95% CI [-7.66%, -1.02%]), in stark contrast to a -14% change reported in the general population (PMID: 33567185); Liraglutide showed a -3.51% change (95% CI [-8.48%, 1.45%]), compared to -8.4% (PMID: 26132939); Dulaglutide led to a -2.33% change (95% CI [-6.80%, 2.13%]), against -10.0% (PMID: 34189841); and Tirzepatide recorded a 2.31% change (CI [-11.47; 20.54]) relative to -15.0% (PMID: 35658024). These findings indicate a substantially reduced weight loss efficacy in breast cancer patients on endocrine therapy compared to the general population. Conclusions: The study concludes that breast cancer patients on endocrine therapy exhibit less significant weight loss with GLP-1 medication treatment than what has been observed in the general population. This suggests that endocrine therapy may reduce the weight-loss efficacy of GLP-1 medications in this particular patient group. Further prospective research is essential to elucidate the mechanisms behind this attenuated response and to develop effective weight management strategies tailored for breast cancer patients undergoing endocrine therapy.