Association between previously studied risk factors and incident RA-ILD. These data came from the 84 BRASS RA-ILD cases and 233 RA non-ILD controls.
| OR Conditioned on Matching Factorsa (95% CI) | Multivariableb OR (95% CI) | |
|---|---|---|
| White, non-Hispanic | 0.61 (0.24–1.54) | 0.57 (0.20–1.60) |
| Joint erosions | 0.79 (0.45–1.40) | 0.74 (0.41–1.34) |
| Rheumatoid nodules | 2.02 (1.15–3.55) | 1.66 (0.89–3.07) |
| C-reactive protein, mg/L | ||
| Normal (< 3) | (ref) | (ref) |
| Low-positive (3 to < 10) | 1.86 (1.04–3.34) | 1.67 (0.87–3.20) |
| High-positive (≥ 10) | 2.79 (1.36–5.69) | 2.61 (1.21–5.64) |
| P for trend | 0.008 | 0.021 |
| DAS28-CRP | ||
| Remission (< 2.6) | (ref) | (ref) |
| Low (2.6 to < 3.2) | 0.46 (0.15–1.37) | 0.47 (0.15–1.45) |
| Moderate (3.2 to < 5.1) | 2.28 (1.21–4.30) | 2.13 (1.09–4.19) |
| High (≥ 5.1) | 4.16 (1.65–10.5) | 4.28 (1.50–12.2) |
| P for trend | < 0.001 | 0.002 |
| MDHAQ score | ||
| 0 to < 0.2 | (ref) | (ref) |
| 0.2 < 1.0 | 1.16 (0.58–2.34) | 1.07 (0.50–2.30) |
| ≥ 1.0 | 3.11 (1.48–6.54) | 3.10 (1.32–7.26) |
| P for trend | < 0.001 | 0.004 |
| bDMARD use | ||
| Never | (ref) | (ref) |
| Past | 1.71 (0.82–3.55) | 1.47 (0.67–3.24) |
| Current | 0.69 (0.38–1.26) | 0.52 (0.27–1.02) |
| Methotrexate use | ||
| Never | (ref) | (ref) |
| Past | 0.51 (0.24–1.06) | 0.38 (0.16–0.86) |
| Current | 0.45 (0.22–0.91) | 0.36 (0.17–0.77) |
| Prednisone use | ||
| Never | (ref) | (ref) |
| Past | 2.03 (0.74–5.59) | 1.44 (0.48–4.34) |
| Current | 3.94 (1.36–11.4) | 3.58 (1.13–11.3) |
Bold values indicate statistical significance to P < 0.05.
↵a All models were conditioned on matching factors (age, sex, RA duration, RF status, and time from study visit to index date).
↵b Also adjusting for anti-CCP, race/ ethnicity, education, BMI, and smoking pack-years. Anti-CCP: anticyclic citrullinated peptide antibody; bDMARD: biologic disease-modifying antirheumatic drug; BRASS: Brigham Rheumatoid Arthritis Sequential Study; CRP: C-reactive protein; DAS28: Disease Activity Score in 28 joints; ILD: interstitial lung disease; MDHAQ: multidimensional Health Assessment Questionnaire; RA: rheumatoid arthritis; RF: rheumatoid factor.