RA-ILD (n=39) | RA-noILD (n=36) | P value | |
Demographics | |||
Female (%) | 28 (71.8) | 33 (91.7) | 0.027 |
Age (mean, SD) | 65±9 | 57±12 | 0.002 |
Ever smoked (%) | 27 (69.2) | 16 (44.4) | 0.030 |
Race, white (%) | 28 (73.7) | 32 (88.9) | 0.095 |
BMI (mean, SD) | 28.4±5.7 | 28.6±7.2 | 0.663 |
Pulmonary function testing* | |||
FVC% (mean, SD) | 76±22 | 94±16 | 0.006 |
TLC% (mean, SD) | 75±22 | 90±22 | 0.081 |
DLCO% (mean, SD) | 48±19 | 67±14 | 0.024 |
RA characteristics | |||
RA disease duration (mean, SD) | 14.8±9.8 | 15.3±10.3 | 0.838 |
DAS 28 | 4.16±1.11 | 4.02±1.61 | 0.962 |
Prednisone use (%)* | 15 (48.4) | 6 (27.3) | 0.054 |
Methotrexate use (%)* | 5 (16.1) | 7 (31.8) | 0.561 |
TNFi use (%)* | 6 (19.4) | 7 (31.8) | 0.684 |
Radiological phenotype | |||
Fibrotic RA-ILD (%) | 20 (51) | ||
Non-fibrotic RA-ILD (%) | 19 (49) |
Time between clinical data and biological sampling is available in the online supplemental results.
*Missing data: pulmonary function: RA-ILD, n=4; RA-noILD, n=24; prednisone, methotrexate and TNFi use: RA-ILD, n=8; RA-noILD, n=14.
BMI, body mass index; DAS 28, Disease Activity Score for 28 joints examined; DLCO%, per cent predicted carbon monoxide diffusing capacity; FVC%, per cent predicted forced vital capacity; RA-ILD, rheumatoid arthritis with interstitial lung disease; RA-noILD, rheumatoid arthritis with no interstitial lung disease; SD, standard deviation; TLC%, per cent predicted total lung capacity; TNFi, tumour necrosis factor inhibitor.