RA Lung Disease Subtypes Have Distinct Risk Factor Profiles

TOPLINE:

Older age, male sex, and seropositivity are linked to a higher risk for rheumatoid arthritis– interstitial lung disease (RA-ILD) with a usual interstitial pneumonia (UIP) pattern, while only seropositivity is associated with RA-ILD with a nonspecific interstitial pneumonia pattern (NSIP).

METHODOLOGY:

• Researchers conducted a case-control study using data from two cohorts in the Mass General Brigham Healthcare system to examine the risk factors associated with different subtypes of RA-ILD.
• They identified 208 patients with RA-ILD (mean age at RA diagnosis, 50.7 years; 67.3% women) and 547 control participants with RA but no ILD (mean age at RA diagnosis, 49.1 years; 78.1% women), who had high-resolution computed tomography (HRCT) imaging data available.
• RA-ILD subtypes such as RA-UIP, RA-NSIP, organizing pneumonia, and others were determined with HRCT scans.
• The associations between demographics, lifestyle, and serologic factors and RA-ILD subtypes were evaluated using multivariable logistic regression analysis.

TAKEAWAY:

• The RA-UIP subtype, the one with worst prognosis, was associated with older age during the time of RA diagnosis (odds ratio [OR], 1.03 per year; 95% CI, 1.01-1.05), male sex (OR, 2.15; 95% CI, 1.33-3.48), and seropositivity (OR, 2.08; 95% CI, 1.24-3.48).
• On the other hand, the RA-NSIP subtype was significantly associated only with seropositivity (OR, 3.21; 95% CI, 1.36-7.56).
• Nonfibrotic ILDs were significantly associated with positive smoking status (OR, 2.81; 95% CI, 1.52-5.21) and seropositivity (OR, 2.09; 95% CI, 1.19-3.67).
• The combination of male sex, seropositivity, and positive smoking status was associated with a nearly sevenfold increased risk for RA-UIP (OR, 6.89; 95% CI, 2.41-19.69), compared with having no RA-ILD risk factors.

IN PRACTICE:

“These findings suggest that RA-ILD subtypes may have distinct risk factor profiles and emphasize the importance of further efforts to understand RA-ILD disease heterogeneity to inform screening and prognostication strategies,” the authors wrote.

SOURCE:

The study was led by Gregory C. McDermott, MD, MPH, Brigham and Women’s Hospital, Boston, and was published online on September 11, 2024, in Arthritis Care & Research.

LIMITATIONS:

This study relied on HRCT imaging, which may have introduced selection bias within the control groups. RA disease activity measures were not available for the Mass General Brigham Biobank RA cohort, which limited the analysis of the influence of disease activity on the risk for RA-ILD. Both cohorts predominantly involved White patients, which may have limited the generalizability of the findings to more diverse populations.

DISCLOSURES:

Some authors were supported by the Rheumatology Research Foundation Scientist Development Award, a VERITY Pilot & Feasibility Award, the Société Française de Rhumatologie, the National Institute of Arthritis and Musculoskeletal and Skin Diseases, and other sources. The authors declared receiving grant support, consulting fees, and honoraria from various organizations and pharmaceutical companies.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.