Could glucagon-like peptide-1 receptor agonists (GLP-1 RAs) nix the inflammation that drives asthma? Maybe, according to a large national study in Denmark.
In the observational study of 27,523 people with a mean age of 54 years, scientists investigated whether GLP-1 RAs could benefit people with chronic and recurring asthma.
While it’s easy to assume that weight loss – which, along with blood sugar regulation, is why many people take these drugs – can help open airways restricted by fatty tissue, the scientists believe that GLP-1s may play a role in regulating airway inflammation.
The study cohort homed in on people from Danish health registers who had been diagnosed with asthma requiring reasonably consistent (more than two prescriptions a year) reliever-inhaler use, and who were also clinically overweight or obese, or had type 2 diabetes, or both.
These individuals had ongoing health data collected from when they began taking a type of GLP-1 medication (fairly evenly split between liraglutide and semaglutide, with 2% prescribed a lesser-known drug such as exenatide, dulaglutide, or lixisenatide.
“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 type 2 diabetes,” the researchers explained in their presentation.
Because GLP-1 RAs are still new in medical-science terms, the class of drugs continues to be developed and intensely studied.
Earlier papers have found links between GLP-1 use and cardiovascular health improvements, as well as talk of the medication's potential in protecting cognitive function and relieving arthritis – all conditions that benefit from weight loss. But that's not necessarily the whole story.
The researchers behind this latest study suggest that ramping up metabolic function has a knock-on effect for chronic inflammatory conditions such as adult asthma.
The data showed that a year after beginning their GLP-1 journey, participants had markedly improved asthma symptoms and less reliance on inhaled corticosteroids (preventive medicines) or acute-event treatment. Overall, the cohort had 26% fewer “exacerbations,” with men showing a 28% improvement, compared with a 23% improvement for women.
The sex distinction is also interesting, as we’re learning more about how our biology differs and, as such, presents more complexity in conditions such as dementia. There's a growing body of evidence uncovering the different immune systems of men and women, which could change how we treat chronic disease.
We also touched on this in the context of the mouth's microbiome and the immune system’s response to dental disease – but nonetheless it's still emerging science.
What we do know, however, is that GLP-1s impact more than just weight loss. In this research, the scientists found that people who were not overweight or obese but had type 2 diabetes showed more improvement in their asthma – 26% compared with 22%.
Overall, spending up to a year on GLP-1s coincided with a reduced reliance on both acute-asthma reliever drugs (down 14%) and corticosteroid use (down 23%). As an asthmatic, I know that when I don’t “feel” it, I’ll drop the daily use of my inhaler – not recommended, of course, but that's when it's under control and not impacting quality of daily life.
Interestingly, individuals in the study who also suffered from allergic rhinitis had 23% fewer flare-ups, and there was a 10% drop in pneumonia episodes compared with pre-GLP-1 medication.
Scientists Simon Høj and Dr Kjell Erik Julius Håkansson, from Copenhagen University Hospital, presented their findings at the recent European Congress on Obesity in Istanbul, Turkey.
The full findings are yet to be published.
It’s also worth noting that the research is preliminary and observational, based only on medical data on GLP-1 use and hospital admissions.
“There's a high chance that the weight loss is a major contributor to these results," warns Håkansson. "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.
“As the use of GLP-1 therapies increases, researchers are finding an increasing number of effects outside of weight loss," he adds.
The challenge will be trying to identify just how much weight loss is playing a role in modulating inflammatory responses, or if there are other GLP-1 mechanisms at play.
Source: European Association for the Study of Obesity via EurekAlert!
Fact-checked by Mike McRae.
