Preoperative Metformin May Improve Surgical Outcomes

Researchers at the University of Pittsburgh School of Medicine (Pitt; PA, USA) and the Veterans Affairs Pittsburgh Healthcare System (PA, USA) conducted a retrospective observational study involving 5,460 patients with T2D who underwent a major surgical procedure at one of 15 community and academic hospitals between 2010 and 2016. The main outcomes and measures were all-cause postoperative mortality, hospital readmission within 90 days of discharge, and preoperative inflammation, with or without preoperative metformin.

The results revealed that preoperative metformin was associated with a 3% 90-day mortality risk in the T2D patients who received preoperative metformin, compared to 5% in those who did not; patients in both groups had the same rate of 30-day mortality (2%). In addition, the 30-day readmission rate was also lower in the preoperative metformin group (11%), than in those without (13%). Preoperative inflammation was also reduced in the metformin group, compared to those without, as measured by mean neutrophil to leukocyte ratio. The study was published on April 8, 2020, in JAMA Surgery.

“This study found an association between metformin prescriptions provided to individuals with type 2 diabetes before a major surgical procedure and reduced risk-adjusted mortality and readmission after the operation,” concluded lead author Katherine Reitz, MD, of the PITT department of surgery, and colleagues, suggesting that “adults with comorbidity have less physiological reserve and an increased rate of postoperative mortality and readmission after the stress of a major surgical intervention.”

Metformin belongs to a class of drugs called biguanides, which inhibit the production of glucose in the liver. In addition to suppressing hepatic glucose production, metformin also increases insulin sensitivity, enhances peripheral glucose uptake, decreases insulin-induced suppression of fatty acid oxidation, and decreases absorption of glucose from the gastrointestinal tract.

Related Links:
University of Pittsburgh School of Medicine
Veterans Affairs Pittsburgh Healthcare System