Inhaler steroids could reduce the risk of lung cancer by around 30 per cent among chronic obstructive pulmonary disease (COPD) patients, according to a new UBC analysis.
The researchers evaluated 10 years' worth of medical and pharmacy data for 39,676 adults in British Columbia who were diagnosed with COPD, including 994 people who were later diagnosed with lung cancer. They compared outcomes for people who took inhaled steroids versus those who used beta agonists, another class of drugs used to treat COPD.
Beta agonists, which work by relaxing muscles in the lungs to widen the airways, are the first choice of treatment for COPD. But doctors will often prescribe steroids, which reduce the number of inflammatory cells called eosinophils in the lungs, for more severe cases.
COPD is a group of diseases, including emphysema and chronic bronchitis, that hamper airflow to the lungs and cause serious long-term disability and early death. Although there is no cure, treatments can help manage the disease.
"In Canada alone, more than 700,000 people have been *diagnosed* with COPD," said study co-author Don Sin, a professor of medicine at UBC and the Canada Research Chair in COPD. "These results highlight the importance of identifying which of those patients may be at the highest risk for lung cancer and may benefit from therapy with inhaled steroids."
The study, recently published in European Respiratory Journal, is limited by its reliance on administrative data, which limits the scope of data available for analysis, and the fact that COPD diagnosis was based solely on prescription records. For the next stage in this research, the researchers plan to do studies to understand how steroids reduce lung cancer risk in COPD patients.
"More work is clearly needed to understand the exact nature of the relationship between lung cancer risks and steroid use," said Lynd. "Over the next few months, we will find out which COPD patients would benefit the most from inhaled steroids."