Association of breastfeeding with tidal breathing analysis in infants with bronchiolitis

Table 1 Characteristics of the study population

Characteristics
n	56
Age (mo)	7.4 ± 2.8
Male sex, n (%)	35 (62.5)
Body weight, kg	7.3 ± 1.6
Body length, cm	65 ± 8.1
Weight-for-length z-score	-0.2 ± 2.0
Gestational age, wk	37.9 ± 1.5 (range 35-41)
Prematurity (< 37 wk)	12 (21.4)
Breastfeeding
No	7 (12.5)
< 2 mo	16 (28.6)
2-6 mo	12 (21.4)
> 6 mo	21 (37.5)
Smoking exposure
In pregnancy	5 (8.9)
After birth	7 (12.5)
In pregnancy and/or after birth	7 (12.5)
Family history of asthma/atopy	9 (16.1)

Values are mean ± SD or number of cases (%).

Table 2 Baseline tidal breathing flow-volume values according to breastfeeding duration

	BF < 2 mo (n = 23)	BF ≥ 2 mo (n = 33)	P value
Tidal volume, mL/kg	8.6 ± 1.8	8.3 ± 2.1	0.580
Respiratory rate, bpm	46.8 ± 20	44.7 ± 18.4	0.687
Expiratory time, s	0.57 ± 0.21	0.55 ± 0.22	0.735
tPEF/tE, %	35.4 ± 15.5	41.3 ± 13.7	0.139

Values are mean ± SD. BF: Breastfeeding; TBFV: Tidal breathing flow-volume; tPEF/tE: Time to peak expiratory flow to total expiratory time.

Table 3 Factors affecting the % time to peak expiratory flow to total expiratory time change after bronchodilation

	Regression coefficient β	P value
Breastfeeding duration	-0.335	0.010
Cigarette smoke exposure	0.353	0.007
Male sex	0.005	0.974
Prematurity	0.031	0.833
Family History of asthma/atopy	0.121	0.379

Multivariable linear regression analysis; the effects of the independent variables were adjusted for each other. tPEF/tE: Time to peak expiratory flow to total expiratory time.