Physician-authored summaries and commentary on the most important medical research, provided by the NEJM Group, a division of the Massachusetts Medical Society.
© Massachusetts Medical SocietyJanuary/February 2025
Metformin and GLP-1-receptor agonists seem to prevent some asthma exacerbations.
Diabetes and obesity are associated with asthma symptoms and exacerbations, and some observational studies have suggested that metformin and glucagon-like peptide-1 (GLP-1)-receptor agonists might be associated with improved asthma control. In this study, UK researchers further explored this issue.
In both a self-controlled case series and a propensity-matched cohort study (together involving 12,000 patients with asthma and type 2 diabetes or pre-diabetes), metformin use was associated with fewer asthma exacerbations (by 24% and 30%, respectively). Adding GLP-1 agonists was associated with an additional 40% reduction in exacerbations. Other diabetes medications showed no effect. These differences were independent of metabolic phenotype (body mass index and glycosylated haemoglobin level) and asthma phenotype (eosinophil count and asthma severity).
Comment: The mechanism of improved asthma control with metformin and GLP-1 agonists is unclear. They might act directly on the lungs, or their effect might be related to weight loss or less hyperglycaemic inflammation (although these factors were controlled for in this study). Because GLP-1 agonists’ effect was independent of eosinophilia (the main marker for type 2 inflammation), they might become an attractive option for patients without type 2 inflammation who are obese. It is too early to manage asthma with these agents in patients without other approved indications based on these retrospective cohort studies, but randomised trials are under way. An excellent accompanying editorial provides further insights.
David J. Amrol, MD, Associate Professor of Clinical Internal Medicine, Director of the Division of Allergy and Immunology, University of South Carolina School of Medicine, Columbia, USA.
Lee B, et al. Antidiabetic medication and asthma attacks. JAMA Intern Med 2024 Nov 18; e-pub (https://doi.org/10.1001/jamainternmed.2024.5982).
Cahill KN, Foer D. Borrowing from the type 2 diabetes armamentarium for asthma. JAMA Intern Med 2024 Nov 18; e-pub (https://doi.org/10.1001/jama internmed. 2024.5983).
This summary is taken from the following Journal Watch titles: General Medicine, Ambulatory Medicine, Hospital Medicine.