TABLE 3

Muscle function and composition

	Controls (n=15)	ILD (n=36)	p-value	ILD subgroups
	Controls (n=15)	ILD (n=36)	p-value	Robust (n=8)	Pre-frail (n=19)	Frail (n=9)
Hand grip (kg)	37±12	34±8	0.37	38±7^a	34±9^a	31±8^a
Quadriceps
Peak torque (Nm)	107±26	95±27	0.10	111±26^a	100±22^a	70±24^b
MVC (Nm)	148±45	141±38	0.57	170±37^a	144±32^a	106±21^b
Endurance (J)	2424±743	2212±620	0.27	2631±603^a	2290±502^a	1620±469^b
CT scan
Mid-thigh muscle CSA (cm²)	245±42	231±50	0.33	271±43^a	232±46^a,b	194±35^b
Skeletal muscle index (cm²·m⁻²)	85±12	79±23	0.37	96±15^a	77±26^a,b	70±15^b
Attenuation (mean HU)	44±4	41±5	0.01	42±5^a	42±5^a	39±5^a

Data are presented as mean±sd, unless otherwise stated. ILD: interstitial lung disease; MVC: maximal voluntary contraction; CT: computed tomography; CSA: cross-sectional area. Different superscript letters indicate a statistically significant difference (p<0.05) between subgroups of patients with ILD such that groups with the same superscript letter are statistically similar but different from groups with a different superscript letter.