Risk for ILD Higher Among Patients With RA, PsA Initiating bDMARDs

Compared with the general population, patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) initiating treatment with biologic/targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) have a higher risk for interstitial lung disease (ILD), according to study results presented at the European Alliance of Associations for Rheumatology (EULAR) 2023 Annual Congress, held from May 31 to June 3, 2023, at Milan, Italy.

Researchers evaluated the risk for ILD in patients with RA or PsA initiating treatment with b/tsDMARDs and age- and sex-matched with those in the general population. The risk for ILD across DMARDs and role of concomitant methotrexate (MTX) were also assessed.

Data regarding b/tsDMARDs, MTX co-medication, and disease activity at treatment initiation were collected.

The incidence of ILD was defined as patients who received 1 or more ILD diagnoses.

The hazard ratios (HRs) for ILD in patients initiating treatment with b/tsDMARDs vs the general population were calculated. Researchers followed-up with patients from treatment start until the first ILD event, end of treatment, death, or after 5 years of follow-up.

For on-treatment analyses, the risk for ILD was compared between those who initiated treatment with etanercept, and those using vs not using concomitant MTX. Follow-up was defined as time to first ILD event, end of treatment plus 29 days, death, or after 5 years.

Using rheumatology registries across 4 countries in Europe, the researchers identified patients with RA or PsA initiating treatment with b/tsDMARDs.  

A total of 37,010 patients with RA, 12,341 patients with PsA, and 569,451 individuals in the general population were included in the study, with 300, 30, 400 cases of ILD, respectively, observed during follow-up.

Compared with the general population, patients with RA and PsA initiating b/tsDMARDs had more than a 10- and a 5-fold increased risk for ILD (HRs, 10.1 [95% CI, 8.6-11.9] and 5.0 [95% CI, 3.4-7.4], respectively).

With regard to on-treatment analyses, the researchers noted a total of 69,608 and 21,340 b/tsDMARD treatment courses among patients with RA and PsA, respectively; 558 and 46 ILD events, respectively, were observed during follow-up.

Patients with RA receiving treatment with rituximab vs etanercept were almost 2 times more likely than those with PsA to develop ILD (HR, 1.7; 95% CI, 1.2-2.4).

The researchers did not observe increased risk for ILD among those who used (51.3% of patients with RA and 42.2% of patients with PsA) vs did not use MTX as a co-medication.

Overall, the study authors concluded, “Among RA and PsA patients initiating b/tsDMARDs, the risk of ILD was higher than in the general population, and the risk of ILD in RA was approximately twice that of PsA patients.”

Disclosure: This research was supported by NordForsk research and FOREUM. Multiple study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.