A Multi-Center Study of the Prevalence and Characteristics of Eosinophilic Phenotype and High IgE Levels Among Chinese Patients with Severe Asthma

Figures & data

Table 1 Demographic Characteristics of the Subjects from Hong Kong Participating in the PREPARE Study

Characteristic	N=232
Age, years, mean±SD	53.9±12.9
Sex, male, n (%)	86 (37.1)
Height, cm, mean±SD	161.3±8.7
Weight, kg, mean±SD	66.5±14.9
Body mass index, kg/m^2, mean±SD	25.5±5.3
Smoking history, n (%)
Active smoker	19 (8.2)
Former smoker	48 (20.7)
Never smoker	165 (71.1)
Duration of diagnosed asthma, years, mean±SD	26.2±15.7
Asthma diagnosed at <12 years of age, n (%)^a	71 (30.7)
Skin prick test, positive, n (%)^b	34 (73.9)
Comorbidities, n (%)
Rhinitis	156 (93.4)
Nasal polyps	17 (10.2)
Sinusitis	2 (1.2)
Atopic dermatitis	30 (18.0)
Asthma associated with NSAIDs	0 (0)
Aspergillosis	0 (0)
Eczema	13 (7.8)
Treatment, n (%)
ICS/LABA	232 (100)
LAMA	75 (39)
LTRA	154 (81)
Chronic OCS	8 (3.4)
Level of asthma symptom control, n (%)
Well-controlled	67 (29)
Partly controlled	92 (40)
Uncontrolled	73 (31)
Number of severe exacerbations in the last year, n (%)
0	175 (75)
1	28 (12)
2	10 (4)
3	9 (4)
>3	10 (4)
Lung function test^c
Pre-bronchodilator FEV1, L	2.0±0.8
Post-bronchodilator FEV1, L	2.0±0.6
Pre-bronchodilator % of the predicted FEV1 value, %	79.7±22.8
Post-bronchodilator % of the predicted FEV1 value, %	83.8±18.4
Pre-bronchodilator FEV1 / FVC, %	68.2±15.0
Post-bronchodilator FEV1 / FVC, %	71.0±13.2
Eosinophil count, cells/mm^3
Mean±SD	312.7±281.6
Median (IQR)	3.2 (1.7, 6.0)
% Eosinophil count, cells/mm^3
Mean±SD	4.3±3.7
Median (IQR)	3.2 (1.7, 6.0)
Total serum IgE, IU/mL
Mean±SD	390.5±912.2
Median (IQR)	123.0 (40.8, 371.5)

Note: ^an=231; ^bn=46; ^cn=57.

Abbreviations: ICS, inhaled corticosteroid; IQR, interquartile range; LABA, long-acting β2 agonists; LAMA, long-acting muscarinic antagonists; LTRA, leukotriene receptor antagonists; OCS, oral corticosteroid; SD, standard deviation.

Table 2 Association of Asthma Control and Asthma Phenotypes

Subjects, n (%)	Overall (N = 232)	Well-Controlled (N = 67)	Partly Controlled (N = 92)	Uncontrolled (N = 73)	p value^a
Eosinophilic phenotype (Blood eosinophils ≥300 cells/mm^3)					0.257
Yes^a	100	28 (28)	35 (35)	37 (37)
No	132	39 (30)	57 (43)	36 (27)
Total serum IgE >100 IU/mL					0.416
Yes	138	44 (32)	54 (39)	40 (29)
No	94	23 (24)	38 (40)	33 (35)
Total serum IgE >150 IU/mL					0.967
Yes	102	29 (28)	40 (39)	33 (32)
No	130	38 (29)	52 (40)	40 (31)
Overlapping eosinophilic phenotype (Blood eosinophils ≥300 cells/mm^3) and total serum IgE >100 IU/mL					0.126
Yes	69	19 (28)	22 (32)	28 (41)
No	163	48 (29)	70 (43)	45 (28)
Overlapping eosinophilic phenotype (Blood eosinophils ≥300 cells/mm^3) and total serum IgE >150 IU/mL					0.016
Yes	50	10 (20)	16 (32)	24 (48)
No	182	57 (31)	76 (42)	49 (27)

Notes: ^ap value from chi-square analysis of ordinal composite variables between each group (Yes/No). p value <0.05 is highlighted in bold.

Figure 1 Association between asthma control levels and asthma phenotype *P ≤ 0.05.

Table 3 Lung Function Parameters According to Asthma Phenotype Characteristics n=57

Subjects, n (%)		Eosinophilic Phenotype (Blood Eosinophils ≥300 Cells/mm^3)			Serum Total IgE >150 IU/mL			Overlapping Blood Eosinophils ≥300 Cells/mm^3 and Serum Total IgE >150 IU/mL
		Yes	No	p value	Yes	No	p value	Yes	No	p value
Total number of patients in the study		100	132		102	130		50	182
Lung function test with results n (%)		30 (30.0)	27 (20.5)	0.129	21 (20.6)	36 (27.7)	0.274	14 (28.0)	43 (23.6)	0.652
Pre-bronchodilator	FEV1, L	1.84 (0.74)	2.06 (0.77)	0.307	1.78 (0.65)	2.05 (0.79)	0.370	1.66 (0.71)	2.04 (0.75)	0.151
	Predicted FEV1%	72.71 (21.40)	86.06 (22.55)	0.006	72.14 (19.85)	83.69 (23.53)	0.068	67.04 (17.33)	83.18 (23.06)	0.015
	FVC, L	2.88 (1.07)	2.89 (0.94)	0.901	2.71 (0.83)	2.97 (1.07)	0.570	2.56 (0.95)	2.97 (1.00)	0.335
	Predicted FVC%	91.10 (22.27)	96.36 (17.82)	0.367	88.81 (13.68)	96.53 (22.44)	0.226	85.68 (16.64)	96.11 (20.48)	0.170
	FEV1/FVC ratio, %	64.80 (14.25)	71.40 (15.27)	0.085	66.35 (17.44)	69.18 (13.84)	0.607	64.71 (15.12)	69.17 (15.04)	0.381
Post-bronchodilator	FEV1, L	1.94 (0.64)	1.97 (0.48)	0.638	1.82 (0.45)	2.01 (0.60)	0.425	1.70 (0.45)	2.02 (0.57)	0.162
	Predicted FEV1%	78.80 (14.97)	88.41 (20.22)	0.043	75.26 (15.23)	87.26 (18.59)	0.032	73.76 (13.88)	86.20 (18.63)	0.032
	FVC, L	2.87 (0.95)	2.74 (0.67)	0.879	2.77 (0.73)	2.83 (0.87)	0.949	2.53 (0.69)	2.88 (0.85)	0.282
	Predicted FVC%	90.76 (16.89)	94.70 (16.53)	0.348	88.12 (10.47)	94.71 (18.39)	0.099	85.00 (11.68)	94.67 (17.21)	0.065
	FEV1/FVC ratio, %	68.47 (12.05)	73.58 (14.05)	0.177	66.57 (12.85)	72.75 (13.07)	0.184	67.52 (11.50)	71.83 (13.56)	0.349

Notes: p value from one-way analysis of variance, those with p values <0.05 are highlighted in bold. Data are presented in mean (standard deviation).

Abbreviation: IgE, immunoglobulin E.