Multinational study
Pierre-Antoine Juge, MD, a rheumatologist at Bichat-Claude Bernard Hospital, Paris, and colleagues performed a case-control study among 482 RA patients with ILD and 741 RA patients without ILD in three cohorts: a French discovery cohort, a multinational (Brazilian, Italian, Mexican, United Kingdom, and United States) replication cohort, and a combined cohort. Those with methotrexate hypersensitivity pneumonitis were excluded.
Dr. Pierre-Antoine Juge
Results showed that relative to peers without ILD, patients with ILD had a lower prevalence of ever having used methotrexate and had received a lower cumulative methotrexate dose, findings that were consistent across all three cohorts.
Methotrexate ever-use was associated with a significantly lower adjusted likelihood of ILD in the discovery cohort (odds ratio, 0.46), the replication cohort (OR, 0.38), and the combined cohort (OR, 0.41). Furthermore, ever-users were less commonly represented among patients with ILD regardless of chest high-resolution CT pattern (usual interstitial pneumonia pattern vs. not).
Finally, methotrexate use appeared to delay the adjusted time to onset of ILD by 3.5 years in the discovery cohort (P = .001), by 3.2 years in the replication cohort (P < .0001), and by 3.5 years in the combined cohort (P < .0001).
“Outside of methotrexate hypersensitivity pneumonitis, methotrexate was not a risk factor for RA-associated ILD in our study. We observed an inverse relationship that was similar whatever the high-resolution CT pattern,” Dr. Juge commented. “But this possible protective effect should be confirmed through a dedicated prospective, randomized, controlled trial.”
“Methotrexate should not be considered as a causal factor for RA-associated ILD, and its [discontinuation] should be discussed through a multidisciplinary discussion,” he recommended. In addition, “this study does not investigate the impact of methotrexate use on RA-associated ILD prognosis.”
The Danish study did not receive any specific funding, and none of its authors reported having any financial disclosures. The multinational study did not receive any specific funding. Dr. Juge disclosed that he had no relevant conflicts of interest, but many of his coauthors reported financial relationships with industry. Dr. Volkmann disclosed consulting for Boehringer Ingelheim and Forbius, and receiving grant support from Forbius and Corbus.
SOURCES: Cordtz R et al. Ann Rheum Dis. 2020;79[suppl 1]:147-8, Abstract OP0232; Juge P-A et al. Ann Rheum Dis. 2020;79[suppl 1]:25, Abstract OP0236.