UK Health Records Study Links Semaglutide to Fewer Asthma Attacks, Researchers Say Don't Get Ahead of the Data

A new study presented at the European Respiratory Society Congress in Barcelona found that people with asthma who started taking semaglutide had noticeably fewer attacks than similar patients who took a different diabetes drug. It's also not a clinical trial, and the researchers behind it are blunt about that distinction.

The work was led by Professor Chloe Bloom, a clinical associate professor in respiratory epidemiology at the National Heart and Lung Institute at Imperial College London, and presented by Dr. Bohee Lee. The team pulled UK electronic medical records and ran four parallel studies, each covering between 20,000 and 22,000 people who started either a GLP-1 receptor agonist or sulfonylureas, an older class of diabetes medication, according to Medical Xpress.

The headline number: semaglutide use was associated with a nearly 40% reduction in asthma attacks. COPD flare-ups dropped about 20% among semaglutide users. Bloom said the effect was strongest at higher doses and among patients with more severe asthma to begin with.

What the drug actually does

Semaglutide is the active ingredient in Ozempic, prescribed for type 2 diabetes, and Wegovy, prescribed for weight management. It belongs to a class of drugs called GLP-1 receptor agonists, which slow digestion and lower blood sugar. Bloom noted that prior research has suggested these drugs carry anti-inflammatory effects that could plausibly help the lungs, but asthma and COPD outcomes have never been a formal endpoint in GLP-1 drug trials. That's the gap this study tried to fill using records instead of a controlled experiment.

The caveat nobody should skip

This is an observational study of medical records, not a randomized controlled trial. That distinction matters. People who start semaglutide and stick with it are not a random sample. They may be more engaged with their own health, more likely to lose weight, more likely to see a doctor regularly. Any of that could produce a similar pattern in the data even if the drug itself weren't doing anything special to the lungs.

Bloom said as much herself: "The findings from this study are encouraging, but they should not change treatment decisions on their own. People with asthma or COPD should not start GLP-1 receptor agonists specifically for their lung condition outside current prescribing guidance. While the findings suggest that some people taking GLP-1 receptor agonists may experience fewer respiratory attacks, this needs confirmation in clinical trials."

That's an epidemiologist telling you exactly what her data can and can't prove.

What outside experts said

Dr. Alexander Mathioudakis, chairman of the European Respiratory Society's Group on Airway Pharmacology and Treatment and a senior lecturer in respiratory medicine at the University of Manchester, wasn't involved in the research but reviewed it. He called it "one of the largest real-world studies to investigate GLP-1 receptor agonists and airways disease," and said it "highlights the need to consider metabolic health as part of respiratory care." He also said it makes a case for building respiratory outcomes into future trials of metabolic drugs, which is a fair point given none currently track that.

Dr. Samantha Walker, director of research and innovation at Asthma + Lung UK, called the findings promising for patients already taking semaglutide for diabetes or obesity, according to MSNBC's coverage of her comments. She also flagged the broader funding picture for lung disease research in the UK, where respiratory conditions remain a leading cause of death but don't draw the same research dollars as other fields.

The honest read

This is a reasonable hypothesis backed by a large dataset. Nobody involved, including the lead researcher, is claiming asthma patients should be prescribed Ozempic or Wegovy off-label to control their breathing. These are already expensive drugs, with UK and US health systems and insurers already straining under GLP-1 demand tied to obesity and diabetes. Expanding prescribing on the strength of a records analysis before a randomized trial confirms the effect would be premature.

The next real test is whether anyone runs a controlled trial that puts asthma and COPD outcomes on the label as an actual endpoint, something Bloom and Mathioudakis both say hasn't happened yet in GLP-1 drug trials. Until that trial exists, this remains a promising correlation in the records, not a new use for the drug.