Table 1.
Patient characteristics according to the presence of any pulmonary function abnormalities
| Characteristic | No PFT abnormalities (n = 114) | PFT abnormalities (n = 45) | P value |
|---|---|---|---|
| Age (years) | 61 ± 7.7 | 63 ± 9.9 | 0.14 |
| Male gender | 41 (36) | 21 (47) | 0.21 |
| Caucasian | 99 (87) | 37 (82) | 0.46 |
| Body mass index (kg/m2) | 29 ± 5.0 | 28 ± 5.5 | 0.12 |
| Ever smoker | 63 (55) | 29 (64) | 0.29 |
| Current smoker | 9 (7.9) | 10 (22) | 0.012 |
| Reported lung disease | 13 (11) | 17 (38) | < 0.001 |
| Emphysema | 2 (1.8) | 8 (18) | < 0.001 |
| Asthma | 12 (11) | 8 (18) | 0.22 |
| Rheumatoid lung disease | 0 (0) | 2 (4.7) | 0.07 |
| CAC > 100 | 34 (30) | 19 (42) | 0.14 |
| RA characteristics | |||
| RA duration (years) | 9.9 (5.6 to 18) | 11 (7.1 to 23) | 0.16 |
| RF seropositive | 64 (56) | 35 (78) | 0.011 |
| Anti-CCP seropositive | 67 (59) | 37 (84) | 0.003 |
| DAS28 (units) | 3.1 (2.4 to 3.7) | 3.1 (2.4 to 4.2) | 0.74 |
| HAQ (units) | 0.75 (0.13 to 1.5) | 0.88 (0.13 to 1.5) | 0.48 |
| Modified Sharp Score (units) | 41 (12 to 99) | 56 (25 to 140) | 0.098 |
| Current prednisone | 35 (31) | 23 (51) | 0.018 |
| Current nonbiologic DMARDs | 99 (88) | 38 (84) | 0.60 |
| Current biologic DMARDs | 55 (49) | 20 (44) | 0.63 |
| Reported pulmonary symptoms | |||
| Any reported symptoms | 41 (36) | 26 (58) | 0.012 |
| Any cough | 19 (17) | 16 (36) | 0.010 |
| Any phlegm | 22 (19) | 16 (36) | 0.030 |
| Any wheezing | 17 (15) | 18 (42) | 0.001 |
| Any breathlessness | 18 (16) | 15 (33) | 0.014 |
Data expressed as mean ± standard deviation, n (%) or median (interquartile range). CAC, coronary artery calcium; CCP, cyclic citrullinated peptide; DAS28, RA Disease Activity Score in 28 joints; DMARDs, disease-modifying antirheumatic drugs; PFT, pulmonary function test; RA, rheumatoid arthritis; RF, rheumatoid factor.