Metformin: Potential Savior from Heart Failure in Anthracycline-treated Diabetes Patients

In an innovative revelation, metformin, a commonly prescribed medication for diabetes mellitus (DM), has emerged as a potential safeguard against heart failure (HF) in patients undergoing anthracycline-based cancer therapies. The study uncovered the connection between metformin advantage in symptomatic HF patients with DM receiving anthracycline treatments. 

The study results were published in the Journal of the American College of Cardiology: Cardio-oncology. 

Heart failure (HF) prevention is critical in anthracycline-treated patients. Metformin, a commonly used diabetic treatment, protects against anthracycline-induced cardiotoxicity in vitro and in animal models. Hence researchers from Pennsylvania, U.S.A. conducted a study to test the association of metformin with the occurrence of symptomatic HF in patients with DM receiving anthracyclines. 

A comprehensive cohort of 561 DM patients embarking on new anthracycline regimens at a tertiary care center formed the basis of this study between 2008 and 2021. To ensure the robustness of the findings, propensity score matching was employed to equitably compare patients taking metformin with those not on this medication. The primary endpoint centered on the development of new symptomatic HF within the first year of anthracycline treatment initiation. 

Results: 

• Among the 315 individuals included in the study (average age of 65 ± 11 years, with 33.7% being male), meticulous matching ensured that patients in the metformin group were highly comparable to those in the non-metformin group in terms of age, gender, cancer type, concomitant medications, and cardiovascular risk factors.
• Strikingly, a mere six patients in the metformin group and 17 of their matched counterparts in the non-metformin group experienced HF within the first year of commencing anthracycline therapy.
• The incidence of HF was significantly lower among those receiving metformin during the initial year of anthracycline treatment.
• Furthermore, the use of metformin was associated with a noteworthy reduction in overall mortality. 

This groundbreaking investigation has unveiled a potential shield against HF and an enhancement in overall survival in DM patients subjected to anthracycline-based chemotherapy - and that shield goes by the name of metformin. Nonetheless, the path forward entails rigorous validation through randomized controlled trials to definitively establish metformin's role as a guardian of cardiac health in this specific therapeutic context. 

Further reading: The Association of Metformin With Heart Failure in Patients With Diabetes Mellitus Receiving Anthracycline Chemotherapy. DOI: 10.1016/j.jaccao.2023.05.013