The study, titled “Inhaled corticosteroids and the risk of lung cancer in chronic obstructive pulmonary disease (COPD): a population-based cohort study,” was published in the European Respiratory Journal.
Inhaled steroids can be prescribed to treat COPD, particularly in more severe cases in which first-line treatments like beta agonists aren’t enough. Beta agonists work by relaxing muscles in the lungs to widen the airways. Meanwhile, steroids work by decreasing the number of a type of inflammatory cell, called eosinophil, in the lungs.
The relationship between the use of steroids and the risk of lung cancer development — a major cause of death among people with COPD — has not, until now, been assessed.
To learn more, a team led by researchers at the University of British Columbia, in Canada, analyzed data from 1997 through 2007 for 39,676 people in British Columbia with COPD. All patients were over 50 years old (mean age of 70.7 years), and all had received at least three COPD-related prescriptions.
Of the 39,676 COPD patients analyzed, 994 (2.5%) developed lung cancer.
Using this information, along with the prescription data, researchers determined that patients who used inhaled steroids to manage their COPD were much less likely to develop lung cancer — an association that remained constant even when different statistical methods were used.
“Results showed that if you had COPD and consistently used a steroid inhaler, your chances of getting lung cancer were between 25 percent and 30 percent lower, compared to people who took other treatments,” Larry Lynd, PhD, a professor at the University of British Columbia and co-author of the study, said in a press release.
The study, however, has some limitations, the researchers pointed out.
For one thing, it is only showing an association, and not a direct cause-and-effect relationship in which the use of steroids would “prevent” the development of cancer. Additionally, the analysis relied on administrative data and prescription records. While allowing for a larger sample size, this type of data is, predictably, imperfect.
“More work is clearly needed to understand the exact nature of the relationship between lung cancer risks and steroid use,” Lynd said, adding that the team plans to further study the interplay between steroids and lung cancer, as well as to determine which patients might particularly benefit from such treatment.
“Over the next few months, we will find out which COPD patients would benefit the most from inhaled steroids,” Lynd concluded.