- Smooth muscle cells from obese patients contract more than smooth muscle cells in non-obese patients during an asthmatic episode.
- Low-grade inflammation is not the root cause of asthma among obese patients.
- A new treatment targeting the muscle must be considered.
Obesity may tighten the airway and trigger asthma, according to new research published in the American Journal of Physiology – Lung Cellular and Molecular Physiology.
According to the researchers, the smooth muscle cells from obese patients contract more compared to non-obese patients during an asthmatic episode.
Healthline reported that this new information could help start a new method of diagnosis and treatment for obese and asthmatic patients.
Dr. Emily Pennington, a pulmonologist at the Cleveland Clinic, thought that the study is “an early step toward understanding the molecular mechanisms that cause the differences in asthma prevalence and severity”.
This research, however, invalidated the belief that low-grade inflammation is the root cause of asthma among obese patients.
“It’s not just the inflammation, it’s the smooth muscles,” clarified Dr. Stokes Peebles, a pulmonologist and allergy specialist at Vanderbilt University Medical School.
Meanwhile, vice chancellor for Translational Medicine and Science Dr. Reynold Panettieri, who is also one of the study’s authors, explained that during optimum conditions, the smooth muscles in our airways are relaxed. We breathe in and out with little consternation. But add an irritant to the mix, such as an allergen, and the conditions in your airway will change.
“It’s the intrinsic nature in these cells. If that muscle contracts more, then there is more obstruction, tightening of the chest,” Panettieri told Healthline.
This study further explained the problem that physicians encounter with asthmatic obese patients who use traditional steroid inhalers. Allegedly, many do not find any relief, unlike non-obese patients, according to Peebles.
Sample cells, which were classified according to genders, were taken from ‘obese’ and ‘non-obese’ cadavers for the study.
Both sets of cells were subjected to histamines, a chemical that the body produces in response to allergen exposure, and carbachol, a drug that can simulate what happens when muscles contract.
Findings showed that the smooth muscle collected from the obese subjects manifested more “shortening” or contraction than the cells derived from the non-obese subjects. Also, female cells contracted more than the male cells.
This discrepancy has also reflected current asthma rated in both genders which shows that obese women have higher asthma rates compared to obese men. The Centers for Disease Control and Prevention (CDC) further revealed that women were more affected than men, roughly 15 percent versus 7 percent.
Thus, other methods should be considered since steroids may be less effective among obese patients.
Penettieri said that for this asthmatic group, there may be a need to shift for a treatment.
“Relaxing the muscle, targeting the muscle cells with long-acting dilators,” he said.
Further studies, Pennington emphasized, can help recognize the discrepancy in asthma-causing cells between obese and non-obese patients.