MONDAY, July 13, 2020 (HealthDay News) -- Treatment with the immunosuppressant methotrexate does not raise the risk of lung disease among rheumatoid arthritis patients, two new studies claim.
At least 5% to 10% of rheumatoid arthritis (RA) patients develop interstitial lung disease, which leads to inflammatory changes in lungs that are accompanied by a dry cough and breathing difficulties.
Severe disease may cause scarring of lung tissue (fibrosis), which may lead to a lifelong dependency on oxygen or even a lung transplant. Lung disease is the cause of premature death in 10% to 20% of RA patients, according to researchers.
The RA treatment methotrexate has been suspected of increasing the risk of interstitial lung disease (ILD) in RA patients.
But these two studies concluded that methotrexate does not appear to be an additional risk factor for the lung disease in RA patients.
In the first study, researchers analyzed data from more than 30,000 RA patients in Denmark for the lung disease and breathing conditions.
"RA patients have a higher risk of suffering from interstitial lung disease than the general population. However, based on our large dataset, there is no evidential correlation to the treatment with methotrexate," said study author Lene Dreyer, from Aalborg University in Denmark.
The second study was conducted in France.
"In a total of 1,223 RA patients, we were not only able to show that MTX [methotrexate] has no impact on the development of interstitial lung diseases but, in fact, may contribute to delaying this development," said study author Pierre-Antoine Juge, from the Bichat-Claude Bernard Hospital in Paris.
"The number of RA patients affected by ILD therapy was reduced by more than half in comparison with RA patients not receiving any MTX treatment," Juge said in a European League Against Rheumatism (EULAR) news release.
"Of course, further examinations are required to support the results and assure patients and physicians that treatment with MTX does not have any negative impact on the pulmonary health of patients suffering from rheumatoid arthritis," EULAR scientific chair John Isaacs said in the release. He is from the University of Newcastle in England.
The American Lung Association has more on interstitial lung disease.
SOURCE: European League Against Rheumatism, news release, July 7, 2020