Association of Maternal Age to Development and Progression of Retinopathy of Prematurity in Infants of Gestational Age under 33 Weeks

Table 3

Univariate analyses of risk factors for the laser treatment in gestational age <33 weeks infants.

Variable	Untreated infants (𝑛=137)	Treated infants (𝑛=45)	P value	Odds ratio	95% CI
Gestational age (weeks)^†	30.0 (28.3–31.8)	26.0 (24.2–27.5)	<𝟎.𝟎𝟎𝟏^∗	0.507	0.411–0.625
Birth weight (g)^†	1217 (901–1524)	754 (595–894)	<𝟎.𝟎𝟎𝟏^∗	0.996	0.995–0.998
Maternal age (years)^†	33 (30–37)	30 (28–34)	𝟎.𝟎𝟏𝟐^∗	0.917	0.852–0.986
SGA (𝑛, %)	49 (36)	13 (29)	0.398	0.730	0.350–1.519
Apgar score; 1 min^†	6 (3–8)	3 (2–5)	<𝟎.𝟎𝟎𝟏^∗	0.783	0.680–0.901
Apgar score; 5 min^†	8 (6–9)	6 (4–7)	<𝟎.𝟎𝟎𝟏^∗	0.700	0.588–0.833
Multiple birth (𝑛, %)	42 (31)	6 (13)	𝟎.𝟎𝟐𝟐^∗	0.348	0.137–0.885
Gender; Male (𝑛, %)	72 (53)	23 (51)	0.866	0.944	0.481–1.852
Pulmonary surfactant (𝑛, %)	57 (42)	29 (64)	𝟎.𝟎𝟎𝟖^∗	2.544	1.265–5.115

CI: confidence interval; ROP: retinopathy of prematurity; SGA: small for gestational age.
^∗𝑃<0.05.
†Median (interquartile range).