Table 2– Characteristics of the four clusters of the Cohort for Reality and Evolution of Adult Asthma in Korea (COREA) patients

	Cluster A	Cluster B	Cluster C	Cluster D	p-value
Subjects n	81	151	253	239
Male	97.4	41.3	47.2	25.8	<0.001
Age at onset years	46.2±12.6	38.8±15.1	21.8±9.4	47.8±9.7	<0.001
Body mass index kg·m⁻²	24.71±2.43	23.50±3.09	23.09±3.45	24.35±3.07	<0.001
Smoking pack-years	34.4±14.1	3.2±6.5	2.0±3.7	2.0±5.3	<0.001
Atopy	34.6	49.7	66.0	53.6	<0.001
History of healthcare usage	22.2	46.4	36.8	23.4	<0.001
Rhinitis	58.3	65.3	73.4	65.0	0.056
Post-BD FEV₁ % pred	82.47±16.45	56.48±13.7	88.62±11.24	97.94±11.5	<0.001
Post-BD increase in FEV₁ % pred	5.90±7.75	12.00±12.07	6.24±7.52	4.34±6.56	<0.001
Post-BD FEV₁/FVC % pred	71.44±11.76	67.84±12.40	84.76±8.69	80.25±7.40	<0.001
PC₂₀ mg·mL⁻¹	4.95±6.14	3.11±5.35	5.49±6.04	5.64±6.47	0.03
Blood eosinophils %	4.80±4.33	5.60±5.48	5.50±6.43	5.02±4.70	0.612
Blood eosinophil count cells·mm⁻³	388.4±376.6	409.6±454.2	377.9±354.3	331.0±301.1	0.247
Log blood eosinophil count	2.42±0.44	2.40±0.47	2.41±0.41	2.34±0.42	0.445
Blood neutrophil count cells·mm⁻³	4397± 1971	4672±3168	4107±1775	3631±1606	<0.001
Serum CRP mg·dL⁻¹	0.78±2.43	0.61±0.90	0.21±0.35	0.37±0.96	0.02
Serum uric acid levels mg·dL⁻¹	5.85±1.35	5.13±1.51	5.10±1.39	4.85±1.60	<0.001
Serum total IgE log IU·L⁻¹	2.41±0.62	2.26±0.59	2.35±0.60	2.14±0.61	0.008

Data are presented as % or mean±sd, unless otherwise stated. Comparison between study groups is based on one-way ANOVA for continuous variables and a Chi-squared test for proportions. BD: bronchodilator; FEV₁: forced expiratory volume in 1 s; % pred: % predicted; FVC: forced vital capacity; PC₂₀: provocative concentration causing a 20% fall in FEV₁; CRP: C-reactive protein.