A study that included more than 400,ooo people with COPD or asthma found that older people who use steroid inhalers for their condition are more likely to suffer lung infections caused by nontuberculous mycobacteria.

The study was published in the European Respiratory Journal.

“These infections are not particularly common but they are chronic and difficult to treat, and are associated with an increased risk of death,” lead researcher Dr. Sarah Brode said in prepared remarks. “Treatment typically requires at least three antibiotics given for longer than a year and this can still fail to tackle the infection.”

From the 417,494 people enrolled in the study, researchers said that 2,966 of them were also diagnosed with nontuberculous mycobacteria infections. The scientists then compared this data with whether the patient used a steroid inhaler, what type of steroid they used and how often they used it.

The team concluded that people using steroid inhalers were twice as likely to be diagnosed with an infection from nontuberculous mycobacteria. The steroid fluticasone was particularly risky, the researchers reported, and the longer patients had been taking the steroid, the greater their risk of developing a hard-to-treat infection.

“Steroid inhalers are critical treatments for managing asthma symptoms for most patients. Although they have also been shown to benefit patients with COPD, they are less important in the management of this condition, and they may only provide more benefit than harm in a sub-set of COPD patients,” Brode said. “There is an ongoing debate on which patients with COPD should be treated with inhaled steroids.

“This research suggests that patients should discuss whether they need to use steroid inhalers with their clinicians, and whether the benefits outweigh the potential harms. If they do need to use them, they should be on the lowest effective dose.

“Clinicians should carefully consider the potential benefits and harms of steroid inhalers in patients with asthma or COPD, especially those who have already had an infection of this type in the past.”

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