Retinopathy of prematurity progression and its related factors: A cohort study in preterm infant in northern Iran

Retinopathy of Prematurity (ROP) is a vasoproliferative retinal disease in premature infants, causing lifetime visual impairment and blindness at an early age. The aim of this study was to investigate the impact of oxygen profile in the progression of ROP.

This prospective cohort study (from 2010 to 2020) was applied in the Ophthalmology center of Ayatollah Rouhani Hospital in Babol (Babol University of Medical Sciences, Babol, Iran) included 828 infants (<37 weeks of gestation with a birth weight <2500 g). Moreover, the oxygen profile of infants (with/without ROP) was collected from their history profile in terms of arterial blood gas.

The duration of oxygen therapy was significantly higher in ROP patients (9.19±14.33 days), compared to control (3.16±4.35 days), (P=0.002). The minimum level of PO2 was significantly lower in ROP infants (51.71±44.81 mmHg) compared to controls (92.75±65.45 mmHg, P<0.001). Furthermore, patient with zone 1 involvement had higher PO2 level than the patient with zone 2 involvement (P=0.029). The ventilation requirement was more frequent in ROP patients (39.27%) compared to controls (19.24%, P<0.001). Also, the CPAP requirement was more frequent in ROP patients (48.51%) compared to controls (32.95%, P<0.001).

Our results have indicated that the duration of oxygen therapy and the minimum and maximum level of PO2 are indicators of ROP occurrence.