Understanding recurrent wheezing: A parent’s guide

Table 1 Baseline characteristics and investigations at enrollment, n (%)

Characteristics	Recurrent wheezing (n = 33)	Non-recurrent wheezing (n = 96)	P value
Male	13 (39.39)	46 (47.92)	0.425
Age (months)	27.68 ± 14.95	30.61 ± 14.52	0.330
Age category (months)
> 36-60	10 (30.30)	26 (27.08)	0.477
> 24-36	13 (39.39)	30 (31.25)
> 12-24	8 (24.24)	24 (25.00)
≤ 12	2 (6.06)	16 (16.67)
Preterm birth	2 (7.69)	8 (9.20)	0.585
Low birth weight	2 (7.69)	9 (10.47)	0.425
Cesarean birth	15 (60.00)	50 (60.98)	0.555
Allergic rhinitis	7 (21.21)	4 (4.17)	0.006
Atopic dermatitis	4 (12.12)	12 (12.50)	0.612
History of food/drug allergy	2 (6.06)	3 (3.12)	0.602
Urban residency	23 (69.70)	73 (76.04)	0.493
Underlying disease	14 (42.42)	23 (23.96)	0.048
Hematologic disease	4 (12.12)	4 (4.17)	0.202
Maternal smoking during pregnancy	2 (9.09)	11 (11.58)	0.542
Secondhand smoke	52 (22.73)	23 (4.21)	0.560
Parental asthma	4 (16.00)	0 (0.00)	0.002
Daycare attendance	17 (70.83)	53 (55.79)	0.247
Hct	33 ± 35.55	96 ± 36.43	0.129
WBC	14420.30 ± 5268.52	11057.81 ± 4466.33	< 0.001
Neutrophil (%)	50.37 ± 20.89	50.37 ± 18.86	0.112
ANC	8965.52 ± 5118.23	5843.84 ± 3702.22
Lymphocyte (%)	32.72 ± 18.43	39.76 ± 18.42	0.061
ALC	4240.18	4535.91	0.660
Eosinophil (%)	2.20 ± 1.83	1.03 ± 1.34	< 0.001
AEC	322.85 ± 318.11	113.80 ± 151.50	< 0.001
Eosinophilia (AEC > 500)	9 (27.27)	3 (3.12)	< 0.001
Platelet count	361393.90 ± 106626.40	339863.20 ± 99551.72	0.295
Anemia	7 (21.21)	14 (14.58)	0.416
Pet ownership			0.250
None	17 (80.95)	83 (89.25)
Dog	1 (4.76)	6 (6.45)
Cat	3 (14.29)	3 (3.23)
Both dog and cat	0 (0.00)	1 (1.08)
Post-RSV infection	12 (38.71)	58 (65.91)	0.011
Influenza A	0 (0.00)	2 (2.33)	0.539
Post-LRTI	21 (63.64)	20 (20.83)	< 0.001
Post-URTI	19 (57.58)	47 (48.96)	0.425

Hct: Hematocrit; WBC: White blood cell count; ANC: Absolute neutrophil count; ALC: Absolute lymphocyte count; AEC: Absolute eosinophil count; LRTI: Lower respiratory tract infection; URTI: Upper respiratory tract infection.

Table 2 Univariable logistic regression analysis of risk factors for recurrent wheezing

Risk factors	OR	95%CI	P value
Male	1.42	0.63-3.17	0.398
Age (months)
> 36-60	Reference	Reference
> 24-36	1.23	0.43-2.99	0.811
> 12-24	0.87	0.29-2.56	0.796
≤ 12	0.33	0.06-1.78	0.179
Preterm birth	1.22	0.24-6.11	0.813
Low birth weight	1.40	0.28-6.94	0.678
Cesarean birth	0.96	0.38-2.40	0.930
Allergic rhinitis	6.19	1.68-22.80	0.006
Atopic dermatitis	0.97	0.29-3.23	0.955
History of food/drug allergy	2.00	0.32-12.52	0.459
Urban residency	1.38	0.57-3.32	0.472
Underlying disease	2.34	1.02-5.39	0.046
Hematologic disease	3.17	0.75-13.48	0.118
Maternal smoking during pregnancy	0.76	0.16-3.72	0.739
Secondhand smoke	0.92	0.31-2.77	0.883
Daycare attendance	1.92	0.73-5.07	0.185
Anemia	1.58	0.58-4.32	0.376
Eosinophilia (AEC > 500 cells/μL)	1.00	1.00-1.01	< 0.001
Pet	1.57	0.77-3.20	0.217
Post-RSV infection	0.33	0.14-0.76	0.010
Post-LRTI	6.65	2.80-15.77	< 0.001
Post-URTI	1.41	0.64-3.14	0.394

AEC: Absolute eosinophil count; RSV: Respiratory syncytial virus; LRTI: Lower respiratory tract infection; URTI: Upper respiratory tract infection.

Table 3 Multivariable logistic regression analysis of potential risk factors for recurrent wheezing

Potential risk factors	Adjust odds ratio	95%CI	P value
Male	1.13	0.80-1.60	0.482
Age (months)
> 36-60	Reference	Reference
> 24-36	1.12	0.71-1.75	0.625
> 12-24	2.38	1.50-3.78	< 0.001
≤ 12	NA	NA	NA
Preterm birth	1.66	1.07-2.58	0.024
Allergic rhinitis	1.50	1.04-2.17	0.031
Atopic dermatitis	0.51	0.26-0.98	0.044
Urban residency	1.68	1.19-2.38	0.003
Hematologic disease	2.43	0.78-7.57	0.126
Maternal smoking during pregnancy	1.60	0.71-3.60	0.254
Secondhand smoke	0.50	0.26-0.98	0.045
Daycare attendance	1.19	0.85-1.66	0.315
Eosinophilia (AEC > 500 cells/μL)	3.29	1.57-6.91	0.002
Pet	1.04	0.57-1.89	0.907
Post-RSV infection	1.22	0.83-1.81	0.312
Post-LRTI	1.82	1.20-2.76	0.005
Post-URTI	0.81	0.57-1.14	0.232

AEC: Absolute eosinophil count; RSV: Respiratory syncytial virus; LRTI: Lower respiratory tract infection; URTI: Upper respiratory tract infection; NA: Not available.