Disease phenotype associations in patients with SSc with or without synovitis.
| Patient Characteristic | Whole SSc Population, n = 7286 | Patients with Diffuse Cutaneous Subtype, n = 2393 | Patients with Limited Cutaneous Subtype, n = 4210 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| With Synovitis, n = 1191 | Without Synovitis, n = 6095 | p | Stepwise Regression, OR (95% CI) | With Synovitis, n = 484 | Without Synovitis, n = 1909 | p | Stepwise Regression, OR (95% CI) | With Synovitis, n = 570 | Without Synovitis, n = 3640 | p | Stepwise Regression OR (95%CI) | |
| Age, mean ± SD, yrs | 58 ± 16 | 58 ± 15 | 0.8 | NS | 54.7 ± 14 | 55.5 ± 15 | 0.3 | NS | 60.4 ± 16 | 60.0 ± 17 | 0.6 | NS |
| Females (%) | 1029 (86) | 5237 (86) | 0.88 | NS | 389 (80) | 1504 (79) | 0.5 | NS | 516 (91) | 3275 (90) | 0.9 | NS |
| Disease duration, mean ± SD, yrs | 10 ± 8 | 9 ± 8 | 0.61 | NS | 7.8 ± 9 | 8 ± 10 | 0.6 | NS | 9.4 + 9 | 13.3 ± 11 | 0.004* | 0.78 (0.57–0.90) |
| Friction rub, n (%) | 291 (24) | 511 (8) | < 0.0001* | 2.21 (1.82–2.67) | 173 (36) | 313 (16) | < 0.0001* | 2.07 (1.62–2.65) | 93 (16) | 167 (5) | < 0.0001* | 2.67 (1.96–3.63) |
| Joint contracture, n (%) | 587 (49) | 1677 (27) | < 0.0001* | 1.81 (1.55–2.11) | 302 (62) | 865 (45) | < 0.0001* | 1.38 (1.09–1.74) | 240 (42) | 735 (20) | < 0.0001* | 2.12 (1.72–2.62) |
| Raynaud phenomenon, n (%) | 1144 (96) | 5802 (95) | 0.36 | NS | 466 (96) | 1822 (95) | 0.7 | NS | 551 (97) | 3488 (96) | 0.5 | NS |
| Digital ulceration, n (%) | 468 (39) | 1823 (30) | < 0.0001* | NS | 241 (50) | 741 (39) | < 0.0001* | NS | 202 (35) | 993 (27) | 0.0001* | NS |
| Muscle weakness, n (%) | 488 (41) | 1462 (24) | < 0.0001* | 1.47 (1.26–1.72) | 264 (55) | 606 (32) | < 0.0001* | 1.95 (1.56–2.44) | 189 (33) | 715 (20) | < 0.0001* | 1.53 (1.23–1.91) |
| Pulmonary fibrosis, n (%) | 505 (42) | 2102 (34) | < 0.0001* | NS | 266 (55) | 951 (50) | 0.09* | NS | 193 (34) | 1023 (28) | < 0.0001* | NS |
| Elevated systolic pulmonary artery pressure, n (%) | 408 (34) | 1348 (22) | < 0.0001* | 1.49 (1.28–1.73) | 185 (38) | 453 (24) | < 0.0001* | 1.51 (1.20–1.91) | 182 (32) | 770 (21) | < 0.0001* | 1.52 (1.22–1.89) |
| Renal crisis, n (%) | 41 (3.5) | 119 (2) | 0.002* | NS | 29 (6) | 72 (4) | 0.04* | NS | 8 (1) | 41 (1) | 0.6 | NS |
| Positive antinuclear antibodies, n (%) | 1094 (92) | 5523 (91) | 0.97 | NS | 437 (90) | 1734 (91) | 0.9 | NS | 516 (91) | 3347 (92) | 0.3 | NS |
| Positive antitopoisomerase-1 antibodies, n (%) | 497 (42) | 1796 (29) | < 0.0001* | 1.29 (1.08–1.53) | 319 (66) | 998 (52) | < 0.0001* | NS | 144 (25) | 714 (20) | 0.002* | NS |
| Positive anticentromere antibodies, n (%) | 286 (24) | 2110 (35) | < 0.0001* | NS | 29 (6) | 111 (6) | 0.9 | NS | 230 (40) | 1821 (50) | < 0.0001* | NS |
| Elevated CPK, n (%) | 120 (10) | 461 (8) | 0.005* | NS | 73 (15) | 221 (12) | 0.05* | NS | 30 (5) | 174 (5) | 0.7 | NS |
| Elevation of acute-phase reactants, n (%) | 541 (45) | 1612 (26) | < 0.0001* | 1.49 (1.28–1.74) | 271 (56) | 690 (36) | < 0.0001* | 1.67 (1.34–2.07) | 218 (38) | 802 (22) | < 0.0001* | 1.77 (1.43–2.17) |
| Proteinuria, n (%) | 107 (9) | 328 (5) | < 0.0001* | NS | 61 (13) | 152 (8) | 0.02* | NS | 31 (5) | 141 (4) | 0.08 | NS |
NS: not significant; CPK: creatine phosphokinase; SSc: systemic sclerosis.
↵* Variables included for the multivariate stepwise logistic regression analysis.