A study has found that high-dose use of inhaled corticosteroids may increase the risk of developing idiopathic pulmonary fibrosis (IPF).

Soon Chun Hyang University Hospital in Seoul announced on Monday that a research team led by Professor Yoon Hee-young of the Department of Allergy and Respiratory Diseases has released a study analyzing data from the National Health Insurance Service National Sample Cohort (NHIS-NSC).

The research team analyzed 57,456 patients diagnosed with chronic obstructive pulmonary disease (COPD) or asthma between 2002 and 2019, of whom 9,492 (16.5 percent) used inhaled corticosteroids. The team classified the patients into high-, medium-, and low-dose groups based on usage and compared the incidence rates of idiopathic pulmonary fibrosis.

The results showed that the use of inhaled corticosteroids in general was not significantly associated with the risk of IPF. However, the risk jumped by 3.99 times in patients who used high-dose (≥1,000 µg/day) inhaled corticosteroids.

Notably, the association between high-dose inhaled corticosteroids and IPF was more pronounced in patients with concomitant chronic airway disease. A trend toward a lower risk of IPF was observed in younger patients compared to older patients.

“Although a trend was observed that the higher the dose of inhaled steroids, the slightly higher the risk of idiopathic pulmonary fibrosis, this is merely an ‘association’ confirmed in an observational study and cannot be conclusively determined as a causal relationship,” Professor Yoon said. “It is advisable to maintain necessary treatment for patients with asthma or COPD, avoid unnecessary long-term use of high doses, and regularly monitor the dosage.”

The study, titled “Association between inhaled corticosteroids and incidence of idiopathic pulmonary fibrosis: nationwide population-based study,” was published in May in the British Medical Association's academic journal, BMJ Open Respiratory Research.