Patients Taking Inhaled Steroids May Be at Greater Risk for NTM

The prevalence of nontuberculous mycobacterial (NTM) pulmonary disease has been increasing, and a recent study found that patients who use inhaled steroids to control their asthma or other breathing problems may be at a greater risk for developing NTM lung infections.

In the study, researchers analyzed medical records of 549 patients who were diagnosed with NTM lung infections in Northern California between 2000 and 2010. The use of inhaled corticosteroids (ICS) was quantified, along with the use of other airways disease medications, and healthcare utilization within 6 months of NTM pulmonary infection identification.

The analysis revealed that the odds of developing NTM pulmonary infection were 2.7 times greater in those patients who had filled 3 or more prescriptions for an ICS. Furthermore, the longer a person was on an inhaled steroid and the higher the dose, the more likely the patient was to develop an NTM lung infection.

"The increasing prevalence of NTMs is disconcerting because some of the most common types of NTM are harder to treat than multidrug-resistant [tuberculosis]," Stephen J. Ruoss, MD, senior study author and a pulmonologist and intensivist at Stanford University Medical Center in California, said in a statement. "The rapidly growing number of NTM infections has occurred during a time when inhaled steroid use has increased, and we wanted to see if there was a potential connection."

The authors described how the prevalence of inhaled steroid use has increased over time. In the 1980s inhaled steroids were originally used to treat asthma, however, now are often used to treat chronic obstructive pulmonary disease (COPD) and bronchiectasis. Additionally, while NTM infection was reported to be as many as 1.8 cases per 100,000 in the early 1980s, most recent studies have shown the prevalence in some regions may be more than 40 cases per 100,000 persons, according to the authors.

"Inhaled steroids are standard therapy for those with asthma because the benefits have proven in studies and clinical practice to outweigh the risks," Ruoss said. "But as physicians, we should be careful using this class of drugs broadly in patients with COPD."

The authors suggested that physicians must objectively assess whether their patients with COPD or other conditions are benefitting from the use of inhaled steroids. If so, they recommend working to prescribe the lowest effective dose and to continue to monitor for routine mycobacteria infections.

Reference

Liu VX, Winthrop KL, Lu Y, Sharifi H, Nasiri HU, Ruoss SJ. Association between inhaled corticosteroid use and pulmonary nontuberculous mycobacterial infection. [published online September 14, 2018]. Ann Am Thorac Soc. doi: 10.1513/AnnalsATS/201804-245OC.