Metformin Mitigates Adverse Effects of Diabetes on Patients With COPD

Diabetes represents a common comorbidity among patients with chronic obstructive pulmonary disease (COPD) and is associated with an increased risk of death, according to new study findings, which also found that treatment with metformin can mitigate this risk.

While it is known that metformin provides significant benefit to patients with diabetes, there has been speculation that the medication can also benefit patients with both COPD and diabetes because it also possesses pleiotropic anti-inflammatory and antioxidant actions.

The study follows clinical observations indicating that metformin is associated with increased inspiratory muscle strength and improvements in dyspnea, health status, and lung function in these patients.

Between March 2008 and December 2014, researchers identified 4231 patients with COPD from the National Taiwan University Hospital, of whom 556 (13%) also had diabetes. These patients were more likely to have hypertension, cerebrovascular disease, heart failure, coronary artery disease, malignancy, and chronic kidney disease.

Diabetes has been shown to have adverse effects on lung anatomy and physiology, inflammatory responses, and antimicrobial defenses in patients with COPD, and after adjusting for comorbidities, as well as other factors, the researchers found that patients with both COPD and diabetes had 1.62 times higher risk of 2-year mortality than patients with just COPD.

A total of 282 patients received metformin during the study period while the rest received other diabetes medications during the 2-year follow-up period. Patient survival was significantly better among patients taking metformin, who were 54% less likely to die.

When the researchers compared patients with diabetes taking metformin against patients without diabetes, they observed that mortality was not significantly different between the 2 groups. According to the researchers, this finding suggests that metformin use may even reverse the negative impact of diabetes on patients with COPD.

“In short, our data suggest that metformin, if not contraindicated, may be the drug of choice for the treatment of [diabetes] in the presence of COPD,” wrote the researchers, who noted that the potential biological explanations for these beneficial effects are not clearly understood but may involve pleiotropic features.

Reference

Ho T, Huang C, Tsai Y, Lien A, Lai F, Yu C. Metformin use mitigates the adverse prognostic effect of diabetes mellitus in chronic obstructive pulmonary disease [published online April 5, 2019]. Respir Res. doi: 10.1186/s12931-019-1035-9.