Group 1: normal muscle strength | Group 2: reduced HGF and/or EFMS | Group 3: reduced QPT and/or HPT | Group 4: reduced muscle strength of arms and/or legs | p-value# | |
Demographics | |||||
Subjects | 79 | 24 | 37 | 45 | |
Prednisone use yes/no | 29/50 | 11/13 | 16/21 | 19/26 | 0.544 |
Prednisone dosage mg | 14.2±7.8 | 12.0±5.6 | 12.5±6.9 | 11.7±6.7 | 0.267 |
Methotrexate use yes/no | 25/54 | 7/17 | 12/25 | 14/31 | 0.951 |
Methotrexate dosage mg | 11.6±2.2 | 10.0±5.0 | 9.0±4.1 | 9.3±4.1 | 0.065 |
Lung function tests | |||||
DL,CO % pred | 79.6±17.2 | 68.8±16.6 | 66.9±15.9 | 68.7±16.3 | 0.001 |
FVC % pred | 101.5±21.6 | 89.0±17.4 | 91.7±18.8 | 92.7±18.3 | 0.023 |
FEV1 % pred | 87.4±21.7 | 78.0±23.6 | 76.2±23.6 | 78.6±23.2 | 0.037 |
Inspiratory muscle strength | |||||
PI,max % pred | 88.3±25.7 | 67.4±32.0 | 78.6±30.7 | 72.1±30.7 | 0.004 |
Exercise capacity | |||||
6MWD % pred¶ | 86.7±12.5 | 63.3±16.3 | 68.3±14.2 | 67.1±14.6 | <0.001 |
Chest radiograph stage | 2.1±1.4 | 1.9±1.7 | 2.1±1.7 | 2.0±1.7 | 0.864 |
Inflammatory markers | |||||
CRP+ | 7.2±14.1 | 8.6±12.7 | 11.1±17.4 | 11.0±17.3 | 0.193 |
sIL-2R§ | 3452±2472 | 2897±2028 | 3159±2121 | 2958±2028 | 0.281 |
Body composition | |||||
BMI kg·m−2 | 28.2±4.4 | 28.3±4.9 | 27.7±5.2 | 28.0±5.2 | 0.783 |
FFM kg | 57.1±10.3 | 54.1±10.7 | 50.5±9.8 | 52.2±10.0 | 0.016 |
FFM index kg·m−2 | 18.2±2.4 | 17.9±2.7 | 17.0±2.9 | 17.4±2.8 | 0.095 |
Fatigue | |||||
FAS score | 27.1±7.4 | 32.0±8.2 | 30.3±8.3 | 30.4±7.8 | 0.023 |
WHOQOL-BREF | |||||
Facet overall QoL | 6.2±1.4 | 5.2±1.6 | 5.2±1.8 | 5.4±1.7 | 0.004 |
Physical health domain | 13.1±2.7 | 10.7±2.4 | 11.0±2.8 | 11.0±2.7 | <0.001 |
Data are expressed as n or mean±sd, unless otherwise stated. HGF: handgrip force; EFMS: elbow flexor muscle strength; QPT: quadriceps peak torque; HPT: hamstrings peak torque; DL,CO: diffusing capacity of the lung for carbon monoxide; % pred: % predicted; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; PI,max: maximal inspiratory pressure; 6MWD: 6-min walking distance; CRP: C-reactive protein; sIL-2R: soluble interleukin-2 receptor; BMI: body mass index; FFM: fat-free mass; FAS: Fatigue Assessment Scale; WHOQOL-BREF: World Health Organization Quality of Life assessment instrument-BREF; QoL: quality of life. #: group 1 compared to group 4; ¶: % of mean results of the control group; +: normal range <10 mg·L−1; §: normal range 240–3,154 pg·mL−1.