Analysis of longitudinal changes in dyspnea of patients with chronic obstructive pulmonary disease: an observational study

Table 1 Baseline data and annual changes in 137 patients with COPD

	Baseline	Annual change	P value
Age (years)	69.0 ± 0.6
Smoking (current/former)	34/103
Body mass index (kg/m²)	21.2 ± 0.3	-0.14 ± 0.04	0.0013
Resting physiological measurements
FEV₁ (l)	1.22 ± 0.04	-0.0254 ± 0.0059	<0.001
FEV₁ (%predicted)	45.9 ± 1.3	-0.9 ± 0.2	<0.001
FRC (%predicted)	110.0 ± 2.2	1.9 ± 0.4	<0.001
DL_CO (%predicted)	64.6 ± 1.8	-3.5 ± 0.4	<0.001
Peak exercise measurements
Peak V₂ (ml/min/kg)	14.8 ± 0.3	-0.5 ± 0.1	<0.001
Peak V (l/min)	40 ± 1	-2.5 ± 0.2	<0.001
Peak V (%predicted VC)	37.8 ± 0.7	-2.2 ± 0.2	<0.001
Dyspnea measurements
OCD (0-100)	60 ± 2	-0.6 ± 0.3	0.097
mMRC (0–4)	1.1 ± 0.1	0.14 ± 0.02	<0.001
CRQ dyspnea (1–7)	5.28 ± 0.09	-0.10 ± 0.02	<0.001
SGRQ activity (0–100)	43.1 ± 1.8	1.83 ± 0.39	<0.001
Borg score at the end of exercise (0–10)	6.4 ± 0.1	-0.13 ± 0.03	<0.001
Psychological status measurements
HADS anxiety (0–21)	4.7 ± 0.3	0.16 ± 0.08	0.046
HADS depression (0–21)	3.9 ± 0.3	0.17 ± 0.07	0.023

Data presented as means ± SE or number. FEV₁ forced expiratory volume in one second; FRC functional residual capacity, DL_CO diffusing capacity for carbon monoxide, $\dot{V} O_{2}$ oxygen uptake, $\dot{V} E$ minute ventilation, $VT$ tidal volume, VC vital capacity, OCD Oxygen Cost Diagram, mMRC modified Medical Research Council dyspnea scale, CRQ Chronic Respiratory Disease Questionnaire, SGRQ St. George’s Respiratory Questionnaire, HADS Hospital Anxiety and Depression Scale.

ISSN: 1465-993X