Table 2

Demographics, body composition, physical function, and muscle-specific force data of sarcopenic patients with RA (n = 14; 11 women) compared to sex matched healthy controls.

CharacteristicsRA PatientsHealthy Controlsp% Difference: Patients to Controls
Age, yrs61.6 ± 3.3, range 22–7262.2 ± 3.5, range 22–760.311.0
Physical activity (2–8)4.71 ± 0.194.64 ± 0.340.86–1.5
BMI, kg/m225.8 ± 0.827.2 ± 1.50.455.2
Appendicular muscle mass, kg14.1 ± 0.816.2 ± 0.70.00312.7
Total body fat, %42.238.80.30–8.8
Sit-to-stand, n12.6 ± 1.014.4 ± 0.70.1512.4
8-foot up and go, s6.4 ± 0.45.5 ± 0.20.03–17.3
50-foot walk, s9.6 ± 0.77.6 ± 0.40.01–25.7
Single leg balance, s42.4 + 5.558.6 ± 6.30.0727.4
mHAQ (0–3)0.63 ± 0.080.18 ± 0.040.001–253
SF-36 physical component summary score (22–59)39.3 ± 2.150.7 ± 1.2< 0.00122.4
SF-36 mental component summary score (11–62)40.2 ± 1.5444.6 ± 0.90.109.8
VL force, N691.6 ± 58.4785.5 ± 44.50.1012.0
VL volume, cm3391.2 ± 21.4445.0 ± 13.30.0112.1
VL PCSA, cm231.3 ± 2.337.5 ± 2.00.0716.6
VL pennation angle (°)8.5 ± 0.49.7 ± 0.40.0712.0
Voluntary activation capacity, %80.2 ± 3.682.1 ± 3.80.812.4
Muscle-specific force, N/cm223.0 ± 2.121.9 ± 1.90.70–5.0
  • Results presented as mean ± standard error. BMI: body mass index; mHAQ: modified Health Assessment Questionnaire; VL: vastus lateralis; PCSA: physiological cross-sectional area.