Risk factors that affect the degree of bronchopulmonary dysplasia in very preterm infants: a 5-year retrospective study

Table 1 Demographic features of preterm infants with different levels of BPD

Variables	Mild BPD (n = 39)	Moderate BPD (n = 185)	Severe BPD (n = 26)	χ²/H/F	P
Male (n, %)	23 (58.9)	98 (52.9)	16 (61.5)	1.000	0.606^#
GA [weeks, M(P25,P75)]^a	30.1 (29.7,31.0)	30.0 (28.8,30.8)	29.9 (28.4,31.0)	2.291^c	0.318
SGA (n, %)	1 (2.6)	15 (8.1)	5 (19.2)	5.218	0.022*
Birth weight (g, mean ± S)^b	1471.5 ± 213.5	1308.7 ± 246.3	1158.8 ± 265.5	13.431^d	< 0.001
Asphyxia (n, %)	13 (33.3)	87 (47.0)	19 (73.0)	9.973	0.007^#
Placental abruption (n, %)	0 (0)	4 (2.1)	0 (0)	0.043	0.837*
PROM (n, %)	17 (43.5)	82 (44.3)	13 (50)	0.324	0.850^#
Amniotic fluid contamination (n, %)	0 (0)	1 (0.5)	1 (3.8)	2.378	0.123*
Maternal Age ≥ 35 years (n, %)	9 (23.0)	45 (24.3)	10 (38.4)	2.547	0.280^#
HDCP (n, %)	6 (15.3)	40 (21.6)	7 (26.9)	0.011	0.918*
GDM (n, %)	9 (23.0)	50 (27.0)	5 (19.2)	0.882	0.643^#
Hyperthyroidism (n, %)	0 (0)	4 (2.1)	0 (0)	0.043	0.837*
Hypothyroidism (n, %)	2 (5.1)	12 (6.4)	5 (19.2)	4.356	0.113*
Anemia (n, %)	3 (7.6)	6 (3.2)	1 (3.8)	1.396	0.498*
Antenatal fever (n, %)	1 (2.5)	6 (3.2)	0 (0)	0.230	0.631*
Use of glucocorticoids (n, %)	3 (7.6)	11 (5.9)	2 (7.6)	0.236	0.889*

GA Gestational age, GDM Gestational diabetes mellitus, HDCP Hypertensive disorder complicating pregnancy, PROM Premature rupture of membranes, SGA Small for gestational age
*Fisher’s exact probability method
^#Pearson’s chi-square value
^aKruskal-Wallis test
^bOne-way ANOVA, the rest using chi-square test
^cH value
^dF value, the rest are χ² values

ISSN: 1471-2431