Comparison of risk factors between preterm and term infants hospitalized for severe respiratory syncytial virus in the Russian Federation

Figures & data

Table 1 Distribution of RSV among infants hospitalized for a lower respiratory tract infection

Patients, RSV status	All patients (n = 519)	Term patients (n = 182)	Premature patients (GA < 36 weeks, n = 15)	P value
RSV + n (%)	197 (38.0)	182 (37.1)	15 (51.7)	0.118

Abbreviations: RSV, respiratory syncytial virus; GA, gestational age.

Table 2 Patient demographics of RSV-positive and RSV-negative patients

Demographics	All patients (n = 519)	RSV-positive infants (n = 197)	RSV-negative infants (n = 322)	P value*
Age, months (mean, SD)	8.8 (6.4)	7.5 (5.9)	9.7 (6.6)	<0.001
Weight at admission (kg) (mean, SD)	8.5 (2.7)	7.9 (2.6)	8.8 (2.0)	<0.001
Gender, male (n, %)	330 (63.5)	120 (60.9)	210 (65.2)	0.323
Premature (<36 weeks) (n, %)	29 (5.6)	15 (7.6)	14 (4.4)	0.118
Congenital heart disease (n, %)	8 (1.5)	2 (1.0)	6 (1.9)	0.447
Chronic lung disease (n, %)	1 (0.2)	1 (0.5)	0 (0)	0.201

* Note: P < 0.05 RSV-positive versus RSV-negative infants.

Abbreviations: RSV, respiratory syncytial virus; SD, standard deviation.

Table 3 Distribution of risk factors for infants hospitalized for a RSV-positive lower respiratory tract by subgroup

	Term (n = 182)	Premature (n = 15)	P value
Host risk factors
Age (months) at admission (mean, SD)	7.4 (5.8)	8.0 (6.9)	0.768
GA (mean, SD)	39.4 (1.4)	32.4 (2.8)	<0.001
Weight (kg) at admission (mean, SD)	8.0 (2.5)	7.1 (2.9)	0.050
Gender (male, %)	112 (61.5)	8 (53.3)	0.531
Multiple gestation (n, %)	7 (3.9)	5 (33.3)	<0.001
Ever breast-fed (n, %)	171 (94.0)	8 (53.3)	<0.001
Medical risk factors
Congenital heart disease (n, %)	2 (1.10)	1 (0.0)	0.683
Chronic lung disease (n, %)	1 (0.55)	0 (0.00)	0.773
Neurological disease (n, %)	4 (2.2)	2 (13.3)	0.016
Family history of atopy (n, %)	35 (19.2)	3 (20.0)	0.942
Family history of wheezing/asthma (n, %)	22 (12.1)	1 (6.7)	0.530
Social risk factors
Siblings (mean, SD)	0.7 (0.8)	1.3 (0.7)	0.013
Siblings ≤ 8 years (mean, SD)	0.6 (0.7)	1.1 (0.6)	0.007
Daycare attendance (n, %)	4 (2.2)	0 (0)	0.337
Individuals in home (mean, SD)	3.3 (1.2)	3.7 (0.9)	0.215
Smokers in home (n, %)	84 (46.2)	6 (40.0)	0.646
Maternal smoking (n, %)	26 (14.4)	2 (13.3)	0.913
Mother’s age (mean years, SD)	29.0 (4.7)	32.9 (7.3)	0.050
Father’s age (mean years, SD)	32.4 (6.0)	35.1 (7.0)	0.167

Abbreviations: RSV, respiratory syncytial virus; SD, standard deviation.