GLP-1s May Reduce Asthma Attack Frequency, Study Suggests

GLP-1 medications are increasingly used to treat a range of conditions outside of obesity and type 2 diabetes, including heart disease and sleep apnea. But new research suggests these drugs may also benefit lung health.

In a new study, adults with asthma who started taking a GLP-1 experienced nearly 40 percent fewer asthma attacks than their peers on other medications.

The investigators also noted that adults with COPD (chronic obstructive pulmonary disease) experienced 20 percent fewer flare-ups on a GLP-1 than non-users. COPD is an umbrella term for disorders that block airflow and make breathing difficult.

Older GLP-1 medications resulted in more modest reductions in breathing attacks of any kind: The now-discontinued GLP-1 exenatide (Byetta) reduced attacks and flares by 23 percent, while dulaglutide (Trulicity) reduced them by 12 percent.

The results were presented at the European Respiratory Society’s annual meeting, but have not yet been peer-reviewed or published in a journal.

People Who Took a GLP-1 Had Fewer Asthma Attacks

For the study, researchers analyzed electronic medical records from four studies, each including about 20,000 people who started taking either a GLP-1 or a sulfonylurea, an older class of diabetes drugs.

The researchers discovered that people with asthma who took GLP-1 medications experienced fewer asthma attacks than those who took other diabetes medications. This effect was strongest among people taking semaglutide (Ozempic, Wegovy).

“Obesity is strongly associated with asthma. People with asthma who also have obesity and/or type 2 diabetes tend to have more symptoms and a higher risk of asthma attacks,” explains the study coauthor Chloe Bloom, PhD, a clinical associate professor at Imperial College London.

The findings suggest GLP-1s may help bridge the gap, enabling people with asthma to receive more effective treatment in the future.

How Obesity Affects Asthma

“Obesity and diabetes may contribute to airway inflammation, which in turn can cause worse asthma symptoms,” says Jimmy Johannes, MD, a pulmonologist and a critical care medicine specialist at MemorialCare Long Beach Medical Center in California, who wasn't involved in the new research.

Excess fat tissue in the abdomen contains a “significant amount” of inflammatory cells that can produce chemicals called cytokines that may spark inflammation throughout the body, explains Richard Siegel, MD, the codirector of the diabetes and lipid center at Tufts Medical Center and an endocrinologist at Tufts Medicine, both in Boston. Dr. Siegel was not involved in the new study.

“As asthma is also a disease associated with inflammation, the increase in cytokines related to obesity may contribute to asthma in people who may be genetically susceptible,” he says.

GLP-1 Medications May Improve Asthma Symptoms in Several Ways

GLP-1 drugs can reduce weight and improve blood sugar control, both of which could improve asthma, Bloom says. The weight loss linked with GLP-1 medications may help to reduce bodily inflammation, including in the airways, Johannes says.

“Furthermore, there are GLP-1 receptors in the lungs, so there is a question whether GLP-1 medications can have a direct effect on the lungs independent of weight loss,” Johannes says.

But doctors emphasize that these are only theories at this point.

The Study Has Strengths and Limitations

The study has not yet been peer-reviewed or published, which is the gold standard in research. It’s also an observational study, making it difficult to prove cause and effect. Instead, the results only demonstrate a link between the medications and fewer breathing episodes.

“We still need mechanistic studies and clinical trials to understand exactly how [GLP-1s] work and how much of the benefit is due to weight loss versus other effects,” Bloom says.

GLP-1s Won’t Erase the Need for an Asthma Inhaler

Steroid inhalers remain the first-line treatment for asthma. But other treatments can influence symptoms.

“Asthma is influenced by both genetic and environmental factors,” Siegel says. He notes that avoiding allergens and environmental triggers, along with optimal nutrition and exercise, may help with symptoms of the condition. Inhalers and oral and injectable medications typically help with inflammation as well, Siegel says. GLP-1 medications may play a role, too, but more research is needed.

“People with asthma should not start GLP-1 receptor agonists specifically for their lung condition outside current prescribing guidance,” Bloom says.