Are Inhaled Steroids the Best Treatment for Mild Asthma?
A new study sheds some doubt on the question of whether inhaled steroids are the best treatment approach for those who have mild, persistent asthma.1
Mild asthma is different
First, let's talk about a significant way that the mild forms of asthma differ from the more severe forms, which are harder to control. Certain white blood cells in the lung are part of the body's immune system and are called eosinophils. These eosinophils are biomarkers of inflammation in the lung.1
Past studies have shown that many people with mild persistent asthma had very low levels of these inflammatory cells. In contrast, people with severe asthma tend to have very high levels of these same cells. Studies have also shown that people with low eosinophils do not respond as well to steroid treatment.
But information on eosinophils in people with mild asthma has been somewhat lacking. Measuring levels of these biomarkers is complex and generally used only in cases of severe asthma.
Although considered the "gold standard" of asthma treatment, inhaled steroids are expensive and can also sometimes have unwanted side effects. So, researchers decided to take a closer look at people with mild asthma. Their goal was to see if there might be other treatment methods that would work just as well in controlling symptoms.1
Details of the study
The study was funded by the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health (NIH). It was published recently in the New England Journal of Medicine (NEJM). In addition, it was presented at the international conference of the American Thoracic Society in May of this year.
Here are a few facts about the study:1
- Included 295 people over the age of 12 with mild persistent asthma
- Group was divided into two groups, either high eosinophils or low eosinophils
- Participants were assigned in random sequence to each of three treatment groups for 12-week periods: inhaled steroids; long-acting muscarinic antagonists (LAMA), a nonsteroidal treatment for uncontrolled asthma; or placebo
- By the end of the study, each participant had rotated through all 3 different treatment methods
Past studies suggested that about half of people with mild, persistent asthma have low eosinophil levels. But, in this study, 73% of the participants had low levels. This was much higher than expected.
Those who were "eos-low" did not respond any better to inhaled steroids than to placebo. However, the small number who were "eos-high" did respond much more positively to inhaled steroids.
62% of the "eos-low" group responded better to the LAMA treatment than they did to placebo. Although this was a relatively low number, it still suggests that LAMA medicines may be a better choice for mild asthmatics than inhaled steroids.
During the course of the study, there were no significant differences in asthma attacks or treatment failures between any of the groups.
The study authors and other reviewers emphasize that this study was too small a sample size to spur widespread changes in treatment for those with mild, persistent asthma. Although the results are intriguing, there is not enough evidence yet to stop prescribing steroids as the standard. However, the study does add to the overall body of evidence in that direction.
In addition, experts say that these results do indicate a need for larger, more definitive studies in this direction. But for now, people with asthma should continue to follow their doctor’s current treatment plan. It could be that we mild asthmatics will see changes in the future, though. I know I'd love to give up my expensive inhaled steroid!
What are your thoughts? Please share in the comments below!
Do you get muscle cramps caused by your asthma medicine?