Does leflunomide treatment increase the risk of lung disease in rheumatoid arthritis?

The aim of this study was to examine the link between leflunomide (Arava) treatment and lung disease in patients with rheumatoid arthritis. The authors concluded that leflunomide was not associated with increased likelihood of lung disease.

Patients with rheumatoid arthritis (RA) often experience inflammation of the joints, bone damage and reduced physical function. RA patients can also experience complications with their lungs such as lung disease. Lung disease may be transmitted (infectious) or develop on its own (non-infectious).

There are a number of treatments available for RA. However, some treatments will not be effective for everyone and some may cause unwanted side-effects. It is possible that disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate (Rheumatrex) can lead to lung disease. Leflunomide is another type of DMARD that has been used as a treatment for RA for some time, but is also thought to be linked to lung disease. This has not yet conclusively been proven and further investigation is required.

Data from 4579 RA patients across 8 different studies was combined to examine the link between leflunomide and negative effects concerning the lungs. In each study, one group received treatment with leflunomide and was compared to patients receiving either another form of treatment or a placebo (drug-free treatment).

Overall, leflunomide was not associated with any increase in the rate of lung infections. A 36% decrease in the rate of non-infectious events was seen in patients receiving leflunomide.

In the studies where methotrexate was used to compare effects, there was an increase in lungs events associated with methotrexate. 4 deaths due to lung disease were noted, all in patients treated with methotrexate.

The authors concluded that leflunomide treatments for RA had no effect on infectious events in the lungs and decreased the risk of non-infectious events in the lungs.

Treatment times and dosages varied across the 8 included studies, which may affect the outcome.

Consult with your physician if you have concerns regarding side-effects associated with treatments for rheumatoid arthritis.