GLP-1 obesity drugs linked to fewer asthma attacks and reduced inhaler use

Danish register study presented at the European Congress on Obesity has associated glucagon-like peptide-1 receptor agonist treatment with a 26 per cent reduction in asthma exacerbations and lower use of reliever medication among adults with asthma and overweight, obesity or type 2 diabetes

Novel research has linked the use of glucagon-like peptide-1 (GLP-1) receptor agonist drugs in people with asthma to a reduction in asthma exacerbations and a fall in the use of reliever inhalers.

The findings, presented at this year’s European Congress on Obesity in Istanbul, Turkey, which took place in May 2026, showed that treatment with GLP-1 receptor agonists was associated with a 26 per cent reduction in the rate of asthma exacerbations and a 14 per cent reduction in the use of inhaled short-acting β2-agonist reliever medication, such as salbutamol.

The study team was led by Dr. Simon Høj and Dr. Kjell Erik Julius Håkansson of Copenhagen University Hospital, Denmark. It has added to evidence that this class of drug, already widely used to treat obesity and type 2 diabetes (T2DM), may have effects beyond weight reduction and control of blood glucose.

GLP-1 receptor agonists mimic the action of a hormone involved in appetite regulation, insulin secretion and glucose metabolism. Drugs in this class include liraglutide and semaglutide. Their rapid expansion in clinical use has prompted interest in whether they may influence conditions associated with obesity, systemic inflammation and metabolic dysfunction.

Asthma can be harder to control in people who also live with overweight, obesity or T2DM. Excess adipose tissue has been linked with a pro-inflammatory state, altered lung mechanics and reduced response to some standard asthma treatments. These factors can increase symptom burden and raise the risk of acute exacerbations which may require oral or intravenous corticosteroids.

The authors suggested that GLP-1 receptor agonists may improve asthma outcomes through several possible mechanisms, including weight loss, modulation of airway inflammation and improved metabolic function. They also noted that any reduction in asthma exacerbations could reduce exposure to systemic corticosteroids. This may be clinically important because repeated corticosteroid use can increase the risk of adverse effects, including osteoporosis and T2DM.

The researchers conducted a nationwide self-controlled cohort study by use of linked Danish health register databases. Adults were eligible for inclusion if they had a previous asthma diagnosis or had been prescribed and used at least two asthma inhaler prescriptions within 12 months. Participants entered the study on the date of their first GLP-1 receptor agonist dispensing, which served as the index date. Eligible individuals were required to have continuous registration data for at least 12 months before and after that date.

Patients with chronic obstructive pulmonary disease were excluded, as were people with severe asthma who had received relatively expensive biologic therapies within 12 months before or after the index date. The researchers defined overweight or obesity by use of International Classification of Diseases codes, 10th revision. Individuals without recorded evidence of T2DM, including those without a diagnosis or evidence of first-line diabetes medication, were placed in the overweight or obesity group. Those with a T2DM diagnosis or prescriptions for first-line diabetes drugs – such as metformin – were placed in the T2DM group.

The primary outcome was asthma exacerbation, defined as an inpatient hospital contact for asthma and/or a course of systemic oral or intravenous corticosteroids. Secondary outcomes included the use of rescue medication, exposure to inhaled corticosteroids and chest infection events, defined by prescription redemption for antibiotics commonly used to treat lower airway infections.

The study cohort included 27,523 people with asthma. The mean age was 54 years and 66 per cent were female. Overall, 49 per cent had comorbid overweight or obesity, 61 per cent had T2DM and 26 per cent had both conditions. About half of the GLP-1 receptor agonist prescriptions were for liraglutide, 48 per cent were for semaglutide and two per cent were for other drugs in the class, including exenatide, dulaglutide and lixisenatide.

Compared with the year before treatment began, GLP-1 receptor agonist use was associated with a 26 per cent lower asthma exacerbation rate overall. The reduction was 28 per cent among men and 23 per cent among women. When the researchers stratified the analysis according to treatment indication, the effect estimates were similar for people with asthma and overweight or obesity and for those with asthma and T2DM. Exacerbations fell by 22 per cent in the overweight or obesity group and by 26 per cent in the T2DM group.

Reliever medication use fell by 14 per cent overall which suggested a reduction in asthma symptoms. This occurred despite a 23 per cent fall in daily inhaled corticosteroid exposure. Inhaled corticosteroids are commonly used in asthma to reduce airway inflammation, prevent exacerbations and control symptoms.

Pneumonia events were also reduced by 10 per cent. The researchers reported similar decreases in exacerbations among people with allergic rhinitis and those without the condition, at 23 per cent and 28 per cent respectively.

The authors said that updated analyses were under way to examine sex-specific differences in these outcomes.

“In this nationwide cohort of more than 27,000 individuals with asthma and also overweight, obesity or T2DM, use of GLP-1 drugs was associated with significant reductions in exacerbation burden as well as reliever use, exposure to inhaled corticosteroids and pneumonia events, irrespective of whether the drugs were being used to treat obesity or T2DM,” the authors concluded.

The researchers cautioned that the study did not have access to clinical records. As a result, information on body mass index and weight loss among participants was not available. This limits the ability to determine whether the observed improvements were driven primarily by weight reduction, by metabolic effects or by direct anti-inflammatory mechanisms.

“There’s a high chance that the weight loss is a major contributor to these results. A common symptom in both asthma and obesity is shortness of breath, and the presence of excess fatty tissue creates a pro-inflammatory state in the body in general. There’s also evidence from other studies suggesting that the inflammation caused by excess adipose tissue is distinct from the ‘classic’ asthma inflammation which often is driven by allergies or cells called eosinophils,” said Håkansson.

“As the use of GLP-1 therapies increase, researchers are finding an increasing number of effects outside of weight loss,” he added.

https://www.eurekalert.org/news-releases/1128307