Table 1. Comparison of demographic data, body composition, lung function, peripheral muscle performance, and functional capacity of healthy volunteers and SSc patients.
| Control group (n=20) | SSc group (n=20) | p-value | |
|---|---|---|---|
| Demographic data | |||
| Age (years) | 46 (33.5–51.0) | 53 (35.3–62.8) | 0.39 |
| Sex (female) | 19 (95%) | 19 (95%) | 1.00 |
| Height (cm) | 160.1±5.87 | 157.5±6.55 | 0.21 |
| Body composition | |||
| Weight (kg) | 65.2±7.76 | 61.1±9.23 | 0.23 |
| Body mass index (kg/m2) | 25.2 (23.3–29.8) | 23.3 (19.3–27.7) | 0.14 |
| FFM (kg) | 40.3 (24.6–46.8) | 36.3 (29.7–40.7) | 0.81 |
| Fat percentage (%) | 34.8 (27.8–39.3) | 32.6 (21.5–37.8) | 0.29 |
| Lung function | |||
| FVC (% predicted) | 101.5 (90.8–106.8) | 73.5 (58.8–103.8) | 0.011 |
| DLco (% predicted) | 102 (94.5–106.5) | 66.5 (47.5–87.8) | 0.0001 |
| MIP (% predicted) | 95 (83.5–107.5) | 53 (44.3–65.8) | 0.0001 |
| MEP (% predicted) | 79 (72.8–87.5) | 38 (30.3–52.5) | 0.0001 |
| Peripheral muscle performance | |||
| RMS slope | 0.32 (0.12–0.66) | 0.64 (0.18–1.21) | 0.15 |
| MDF slope | -0.07 (-0.19–-0.01) | -0.17 (-0.41–-0.09) | 0.034 |
| Quadriceps strength (kg) | 36 (32–41.4) | 23.1 (18.1–31.2) | 0.0001 |
| 6MWD (% predicted) | 109.5 (96.3–137.9) | 83.5 (73.2–99) | 0.0001 |
Values are medians (interquartile range) or number (%). FFM = fat-free mass; FVC = forced vital capacity; DLco = diffusing capacity for carbon monoxide; MIP = maximal inspiratory pressure; MEP = maximal expiratory pressure; RMS = angle of the linear regression line obtained with the values of root mean square electromyography signal over time during fatigability test of vastus medialis muscle; MDF = angle of the linear regression line obtained with the values of median frequency electromyography signal over time during the fatigability test of vastus medialis muscle; 6MWD = 6-minute walk distance.