Characteristics of Allergic, Eosinophilic, and Overlapping Asthma Phenotypes Among Pediatric Patients with Current Asthma: A Cross-Sectional Study from Saudi Arabia

Figures & data

Table 1 Characteristics of the Enrolled Patients Stratified According to the Asthma Phenotype

Variables	Total Patients (n=321)	Allergic Asthmatic n=169 (52.6%)	Eosinophilic Asthmatic n=144 (44.9%)	Overlapping Allergic and Eosinophilic Phenotype, n=97 (30.2%)
Age, median (IQR), y	8 (6–10)	8 (6–11)	(6–10)	8 (6–11)
Sex, male, n (%)	204 (63.6)	119 (70.4%)	94 (65.3%)	68 (70.1%)
Height, cm, mean (SD)	128 (15.8)	128.6 (16.0)	127.7 (16.7)	129.5 (16.9)
Weight, cm, mean (SD)	29.9 (14.4)	30.5 (15.0)	29.7 (14.7)	31.7 (15.6)
BMI, kg/m^2, mean (SD)	17.2 (4.4)	17.3 (4.6)	17.2 (4.7)	17.8 (4.9)
BMI percentile, median (IQR)	53.8 (6.3–88.2)	51.3 (5.1–90.5)	52.5 (3.9–88.8)	55.4 (5.5–91.6)
BMI- categories
Normal	159 (49.5)	75 (44.4)	64 (44.4)	40 (41.2)
Overweight/obese	85 (26.4)	51 (30.2)	40 (27.8)	33 (34.0)
Family history of asthma, n (%)	238 (74.1)	140 (82.8)	121 (84.1)	84 (86.6)
Associated atopies for at least one, n (%)	274 (85.3)	156 (92.3)	132 (91.7)	93 (95.8)
Allergic rhinitis	253 (78.8)	147 (87.0)	124 (86.1)	87 (89.7)
Eczema	153 (47.7)	95 (56.2)	83 (57.6)	64 (66.0)
Food allergies	56 (17.4)	42 (24.9)	41 (28.5)	33 (34.0)
Eosinophilic esophagitis	6 (1.9)	3 (1.8)	3 (2.1)	3 (3.1)
First wheezy episode, median (IQR), months	21 (12–36)	12 (12–36)	12 (12–36)	12 (12–36)
MD-asthma diagnosis, median (IQR), year	5 (3–7)	5 (3–7)	4.5 (4–7)	5 (3–7)
Management inhaled steroid, Active substance, n (%)
Fluticasone, n (%)	116 (36.1)	63 (37.2)	51 (35.4)	33 (34.0)
Fluticasone/salmeterol, n (%)	120 (37.4)	66 (39.1)	61 (42.4)	40 (41.2)
Budesonide/formoterol, n (%)	23 (7.2)	18 (10.7)	9 (6.3)	7 (7.2)
Montelukast, n (%)	185 (57.6)	99 (58.6)	86 (59.7)	59 (60.8)

Abbreviations: n, number, IQR, interquartile range, SD, standard deviation, BMI, body mass index, MD, medical doctor.

Figure 1 Flowchart of the study population. n = number.

Table 2 Asthma Severity Among the Enrolled Patients Stratified by Asthma Phenotypes

Variables	Total n=321	Allergic Asthma, n=169 (52.6.4%)	Eosinophilic Asthma, n=144 (44.9%)	Overlapping Allergic and Eosinophilic Phenotype, n=97 (30.2%)
Asthma severity, n (%)
Mild	114 (35.5)	44 (26.0)	38 (26.4)	20 (20.6)
Moderate	161 (50.2)	95 (56.2)	80 (55.6)	58 (59.8)
Severe	46 (14.3)	30 (17.8)	26 (18.1)	19 (19.6)
Asthma duration, years, median (IQR)	3 (1–5)	3 (1–5)	3 (1–5)	3 (0.5–5.5)
≥1 hospitalization for asthma exacerbation (ever), n (%)	124 (38.6)	81 (48.0)	71 (49.3)	52 (53.6)
Number of total hospitalization days, median (IQR)	4 (0–10)	6 (0–12)	7 (0–13)	8 (0–14)
ER visit last year, median (IQR)	2 (1–3)	2 (1–3)	2.0 (1–3)	2 (1–3)
OCS last year, median (IQR)	2 (1–2)	2 (1–3)	2 (1–3)	2 (1–3)
Any prior PICU admission, n (%)	74 (23.1)	49 (29.0)	39 (27.1)	30 (30.9)
Previous intubation (ever), n (%)	5 (1.6)	5 (3.0)	4 (2.8)	4 (4.1)
School missing last year, days, (total=1571 days) median (IQR)	5 (2–10)	5 (3–11)	3 (3–10)	5 (3–11)
Asthma control categories, n (%)
Well-controlled	144 (44.9)	71 (42.1)	60 (41.7)	38 (39.2)
Partially controlled	106 (33.0)	53 (31.4)	47 (32.6)	29 (29.9)
Uncontrolled	53 (16.5)	41 (24.3)	32 (22.2)	29 (29.9)
Lung function (spirometry assessment), median (IQR)
Reversibility	6 (2–14)	4 (1–12.8)	4 (0–8.5)	4 (0–8.5)

Abbreviations: n, number, IQR, interquartile range, ER, emergency room, OCS, oral corticosteroid, PICU, pediatric intensive care unit.

Figure 2 Boxplot showing pulmonary Lung function (spirometry assessment) results in 57 patients. The boxes represent the upper and lower quartiles. The line dividing each box is the median value.

Abbreviations: PreFEV 1, pre-bronchodilator forced expiratory volume in 1s; PreFVC, pre-bronchodilator forced vital capacity; PreFEV 1/FVC, pre-bronchodilator FEV1/FVC; postFEV 1, post-bronchodilator forced expiratory volume in 1s; postFVC, post-bronchodilator forced vital capacity; postFEV 1/FVC, post-bronchodilator FEV1/FVC.

Table 3 Factors Associated with Uncontrolled Asthma

Variables	Controlled Asthma N=268, n (%)	Uncontrolled Asthma N=53, n (%)	χ^2	P-value
Family history of BA	192 (71.6)	46 (86.8)	5.298	0.013
Any prior PICU admission ever	53 (19.8)	21 (39.6)	9.070	0.003
Any prior asthma-related hospitalization	131 (48.9)	38 (71.7)	9.241	0.002
ER visits last year	234 (87.3)	51 (96.2)	3.530	0.041
Severe asthma	33 (12.3)	13 (24.5)	5.378	0.022
Eosinophilic phenotype	112 (41.8)	32 (60.4)	4.878	0.020
Overlapping allergic and eosinophilic phenotype	69 (25.7)	28 (52.8)	15.247	<0.001
Allergic phenotype	128 (47.8)	41 (77.4)	8.256	0.003

Abbreviations: χ², Chi-square test; n, number, BA, bronchial asthma, PICU, pediatric intensive care unit, ER, emergency room.

Table 4 Logistic Regression Showing Unadjusted and Adjusted Odds Ratios for Patients with Uncontrolled Asthma

Variables	Comparison	Univariable			Multivariable
		OR	95% CI	P-value	aOR	95% CI	p-value
ER visits last year	Yes vs no	3.7	0.6–15.9	0.078	3.6	0.4–28.9	0.598
Overlapping allergic and eosinophilic phenotype	Yes vs no	3.2	1.8–5.9	<0.001	2.0	0.5–8.4	0.324
Allergic phenotype	Yes vs no	2.7	1.3–5.4	0.005	1.6	0.6–4.0	0.351
Any prior PICU admission ever	Yes vs no	2.6	1.4–4.9	0.003	1.6	0.7–3.4	0.254
Any prior asthma-related hospitalization	Yes vs no	2.6	1.4–5.0	<0.003	1.2	0.5–2.8	0.598
Severe asthma	Yes vs no	2.3	1.2–4.8	0.023	1.6	0.7–3.7	0.238
Family history of BA	Yes vs no	2.6	1.1–6.0	0.025	1.2	0.5–3.1	0.648
Eosinophilic phenotype	Yes vs no	2.0	1.1–3.6	0.029	0.8	0.2–3.7	0.688

Notes: Hosmer and Lemeshow test showed an acceptable model fit (X² = 3.097, p= 0.928). The multivariable logistic regression model included all other variables in the table.

Abbreviations: OR, odds ratio, aOR, adjusted odd ratio, CI, confidence interval, ER, emergency room, PICU, pediatric intensive care unit, BA, bronchial asthma.

Figure 3 Prevalence of asthma control according to the Global Initiative for Asthma (GINA) asthma control guideline in the enrolled patients, stratified by the asthma phenotypes (allergic, eosinophilic, and overlapping allergic and eosinophilic phenotypes). *p ≤ 0.05.