Diaphragmatic excursion is correlated with the improvement in exercise tolerance after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease

Table 1 Baseline characteristics of study participants

	All	Responders	Non-responders	p value
	n = 50	n = 30	n = 20	p value
Age, year	74.9 ± 5.7	74.6 ± 5.8	75.3 ± 5.7	0.95
Gender, male/female (%)	44/6 (88/12)	28/2 (93/7)	16/4 (81/19)	0.16
BMI, kg/m²	22.1 ± 3.6	22.0 ± 2.8	22.3 ± 4.7	0.80
GOLD (I + II/III/IV)	27/17/6	20/8/2	7/9/4	0.07
LTOT, n (%)	5 (10)	3 (10)	2 (10)	0.89
CAT	14 (10–20)	11.5 (8.8–16.8)	18.5 (12.3–20.8)	0.04
FVC %predicted	93.0 ± 20.2	97.3 ± 19.5	86.4 ± 20.0	0.06
FEV₁ %predicted	56.0 ± 21.8	63.2 ± 21.8	45.1 ± 17.1	0.003
SpO₂, %	90 ± 7	91 ± 7	90 ± 6	0.55
%LAA	17.5 ± 16.3	17.0 ± 14.6	18.2 ± 19.0	0.65
6MWD, m	378 ± 88	411 ± 83	328 ± 71	< 0.001
mBorg scale dyspnoea	5 (4–7)	4 (3–7)	6 (4–8)	0.007
mBorg scale leg fatigue	2 (1–5)	2 (0.9–4)	2.5 (1.3–5)	0.50
PI_max, cmH₂O	55.7 ± 21.9	65.7 ± 19.4	40.6 ± 16.2	< 0.001
DE_max, mm	47.9 ± 9.3	52.9 ± 7.8	40.4 ± 5.3	< 0.001
QMS, kgf/kg	0.54 ± 0.14	0.58 ± 0.13	0.48 ± 0.13	0.007

COPD chronic obstructive pulmonary disease, BMI body mass index, GOLD Global Initiative for Chronic Obstructive Lung Disease, LTOT long-term oxygen therapy, CAT COPD assessment test, FVC forced vital capacity, FEV₁ forced expiratory volume in 1 s, SpO₂ saturation of percutaneous oxygen, LAA low attenuation area, 6MWD 6-min walk distance, mBorg modified Borg, PI_max maximum inspiratory pressure, DE_max maximum diaphragmatic excursion, QMS quadriceps muscle strength. Values are presented as means ± standard deviations or median (inter-quartile)

ISSN: 1465-993X