Canadian Respiratory Journal

Research Article

Clinical and Functional Characteristics of Subjects with Asthma, COPD, and Asthma-COPD Overlap: A Multicentre Study in Vietnam

Table 3

Evolution of clinical and functional parameters after 6 months.


	Asthma			COPD			ACO
	Inclusion	6th month		Inclusion	6th month		Inclusion	6th month

Clinical symptoms
Cough + expectoration (%)	25.1	15.7	<0.05	90.5	54.1	<0.001	84.7	52.6	<0.001
Dyspnea crisis (%)	89.4	19.7	<0.001	25.6	10.8	<0.01	57.6	37.2	<0.05
Effort-induced dyspnea (%)	35.5	14.4	<0.01	82.4	51.3	<0.001	91.5	67.7	<0.01
Disease severity^¥
Severe asthma (%)	25.0	7.8	<0.001	—	—	—	—	—	—
Severe COPD (%)	—	—	—	24.3	11.5	<0.01	—	—	—
Severe ACO (%)	—	—	—	—	—	—	27.2	22.0	NS
PFT after BD
FEV₁	80 ± 22	89 ± 14	<0.05	64 ± 17	72 ± 18	<0.05	54 ± 14	69 ± 15	<0.01
FEV₁/FVC	72 ± 8	74 ± 6	NS	62 ± 6	63 ± 7	NS	64 ± 5	66 ± 7	NS
MEF25-50	72 ± 7	74 ± 8	NS	44 ± 12	66 ± 8	<0.01	42 ± 11	63 ± 7	<0.01
TLC	96 ± 14	104 ± 12	NS	118 ± 22	112 ± 24	NS	117 ± 16	108 ± 17	NS
RV	126 ± 19	124 ± 20	NS	158 ± 23	149 ± 23	NS	158 ± 21	155 ± 22	NS
FRC	142 ± 18	140 ± 22	NS	168 ± 21	157 ± 22	NS	167 ± 22	159 ± 24	NS
DLCO	90 ± 12	89 ± 14	NS	73 ± 11	76 ± 13	NS	68 ± 14	79 ± 13	<0.05
Exhaled NO
F_ENO	46 ± 28	18 ± 7	<0.001	15 ± 8	14 ± 7	NS	34 ± 12	15 ± 10	<0.001
C_ANO	4 ± 2	3 ± 2	NS	3 ± 2	4 ± 2	NS	6 ± 3	3 ± 2	<0.05
Exercise testing
VO₂ max	64 ± 12	72 ± 8	<0.05	52 ± 12	67 ± 10	<0.05	56 ± 14	65 ± 15	<0.05
6MWD	388 ± 126	442 ± 103	<0.05	324 ± 144	389 ± 147	<0.05	317 ± 155	332 ± 125	NS
DOD	4 ± 2	3 ± 3	NS	7 ± 3	4 ± 3	<0.05	8 ± 4	6 ± 5	NS
Sleep study
AHI > 15 (%)	35.4	25.0	<0.05	36.5	28.9 ± 6	<0.05	52.7	37.2	<0.01
AHI (times/hour)	16 ± 9	17 ± 8	NS	17 ± 8	15 ± 7	<0.05	24 ± 12	16 ± 11	<0.01
Nadir SpO₂ (%)	86 ± 9	88 ± 8	NS	85 ± 7	86 ± 8	NS	81 ± 8	87 ± 7	<0.05
Treatment option
+SABA as needed	ICS_LD + LABA	ICS_MD + LABA + LTA	—	LABA + LAMA +	ICS_LD + LABA + LAMA + others	—	ICS_LD + LABA + LAMA	ICS_MD-_HD LABA + LAMA + others^#	—

ACO: asthma-COPD overlap; LFT: lung function test; BD: bronchodilator; FEV₁: forced expiratory volume in one second; FVC: forced vital capacity; MEF: mean expiratory flow; TLC: total lung capacity; RV: residual volume; FRC: functional residual capacity; DLCO: diffusing capacity of the lungs for carbon monoxide; NO: nitric oxide; F_ENO: fractional exhaled NO; C_ANO: alveolar concentration of NO; 6MWD: 6-minute walk distance; DOD: differentiation of oxygen desaturation; AHI: apnea-hypopnea index; SABA: short-acting beta-2 agonist; LABA: long-acting beta-2 agonist; LAMA: long-acting muscarinic antagonist; ICS: inhaled corticosteroid; LD: low dose; MD: moderate dose; HD: high dose; LTA: leukotriene antagonist. ^¥Disease severity was defined by LFT and based on FEV₁ percent predicted after BD; severe asthma, COPD, and ACO were defined by FEV₁ < 60%, <50%, and <50% predicted, respectively. ^#Theophylline and acetyl cysteine. Theophylline, acetyl cysteine, and macrolide.