Table 1.
Demographic and clinical data of the included patients with early RA stratified for development of PF
| Characteristics | Early RA with PF (n = 60) | Early RA without PF (n = 1058) |
|---|---|---|
| Age at RA diagnosis, mean (s.d.), years | 64.8 (10.3)*** | 57.4 (14.1) |
| Age at ILD diagnosis, mean (s.d.), years | 73.9 (9.6) | – |
| Females, n (%) | 37 (61.7) | 720 (70.7) |
| Ever-smoker, n (%) | 43/59 (72.9) | 623/1009 (61.7) |
| Current smoker, n (%) | 11/58 (19.0) | 203/1043 (19.5) |
| ACPA positive, n (%) | 43 (80.0) | 705 (69.2) |
| ACPA, median (IQR) | 203.0 (547.4) | 98.2 (415.0) |
| RF positive, n (%) | 53 (88.3)** | 739 (72.5) |
| HLA-shared epitope positive, n (%) | 23 (63.9) | 371 (58.7) |
| Follow-up time from RA diagnosis until 31 December 2016 or death, mean (s.d.), years | 8.7 (4.8) | 9.5 (5.0) |
| BMI, mean (s.d.), kg2/cm | 27.0 (3.7)a | 26.4 (4.5)a |
| DAS28 on index date, mean (s.d.) | 4.8 (1.4) | 4.8 (1.4) |
| DAS28-AUC24, mean (s.d.) | 90.0 (18.8)* | 82.7 (21.5) |
| Death during study period, n (%) | 27 (45.0)*** | 130 (12.3) |
| Treatment at index date, n/N (%) | ||
| Glucocorticoids | 25/45 (55.6) | 454/775 (58.6) |
| MTX | 38/57 (66.7) | 735/859 (85.6)*** |
| csDMARDs ever during follow-up, n/N (%) | 57/58 (98.3) | 1004/1024 (98.0) |
| MTX ever during follow-up, n/N (%) | 39/59 (66.1) | 860/960 (89.6)*** |
| bDMARDs within 24 months, n/N (%) | 12/60 (20.0)* | 113/1050 (10.8) |
| bDMARDs during follow-up, n/N (%) | 23/37 (38.3) | 295/1050 (28.1) |
| Duration of RA at time of PF diagnosis, mean (minimum–maximum), years | 5.4 (−0.58–15.6) | – |
| HRCT, n (%) | 55/60 (91.7) | – |
| VC, mean (95% CI), %b | 88.2 (79.9, 96.5) | – |
| TLC, mean (95% CI), %b | 81.3 (74.5, 88.2) | |
| DLCO, mean (95% CI), %b | 61.1 (52.6, 69.7) | – |
a
Data available in 50 patient with PF and 849 patients without PF.
b
Performed in 25 cases synchronous to radiology.
VC: vital capacity; TLC: total lung capacity; DLCO: diffusion capacity of the lungs for carbon monoxide. *P<0.05, **P<0.01, ***P<0.001.