Analysis of pathogenic factors of retinopathy of prematurity in Heilongjiang Province
Authors: Xiao Zheng , Gao Ya , Zhang Di , Fu Yue , Zhang Shuihua , Li Yuanyuan 
Published: December 2023

Abstract
Background and purpose
Retinopathy of prematurity is a vascular development disorder in immature retinas of premature infants, which is the leading cause of blindness in children worldwide. Because the screening delay may lead to the occurrence of blindness in children, it is particularly important to conduct timely screening for children with high risk factors. Currently, the pathogenesis of ROP may be related to multiple factors such as gestational age and birth weight of premature infants. In this study, the prevalence and risk factors of ROP in Heilongjiang Province were determined through screening for premature infants in the region, aiming to proceed early prevention of the disease.
Methods
Retrospectively analyzed 714 premature infants admitted to the Ophthalmology Clinic of the Second Affiliated Hospital of Harbin Medical University from January 2016 to February 2022. 12 related factors was recorded including patients’ gender, gestational age, birth weight, oxygen duration, blood transfusions, anemia, neonatal infections, respiratory distress syndrome, maternal feeding way, childbirth way, pregnancy age and parity. The prevalence of ROP and the differences in related factors between ROP patientsand non-ROP patients were found.
Results
Among 714 premature infants, 188 had ROP of which the incidence is 26.3%，and 61 patients received treatment. There were statistically significance(P<0.05) in gestational age, birth weight, oxygen duration, blood transfusion, anemia, neonatal infection, respiratory distress syndrome and childbirth way between the 188 ROP patients and non-ROP patients in univariate regression analysis. Variables with statistical significance for single factor were selected and conducted by multivariate regression analysis, which showed that gestational age, birth weight, and oxygen duration had remarkable statistical significance(P<0.05) with the occurrence of ROP. Gestational age and birth weight were the protective factors of disease (OR=0.43 and OR=0.8), while oxygen duration was the risk factor of disease (OR=1.02), and the diagnostic value of the model was high (AUC=0.776). five of the 61 patients who received treatment for ROP accepted two treatments, with gestational age < 32 weeks, birth weight < 1500g, and oxygen inhalation time > 20 days. The Kendall grade relative analysis of 188 patients with ROP showed that disease severity was significantly correlated with gestational age, birth weight, oxygen duration, anemia, blood transfusion and respiratory distress syndrome(P<0.05), in which the gestational age, birth weight, anemia, blood transfusion and respiratory distress syndrome were negatively correlated with the severity of the disease, while oxygen duration was positively correlated with severity of the disease. 507 children were screened from 2016 to December 31th in 2019, 138 of which were ROP patients, 36 children were treated (7.1%). Due to the spread of the COVID-19, 207 children were screened after January 1th in 2020, 50 children were ROP patients, and 25 of whom got treatment (12%), 21were treated after 8 weeks of birth or more than 37 weeks of corrected gestational age. Four out of five children who received the second treatment happened after the epidemic, and three of them missed treatment due to the epidemic.
Conclusions
The gestational age, birth weight and oxygen duration are significantly correlated with the incidence and severity of the disease in premature infants screening of Heilongjiang Province. Premature infants screening and subsequent visit were affected due to the spread of the COVID-19 in the past two years, the proportion of children needed to be cured augmented apparently, therefore, it matters a lot for premature infants to be screened standardly and timely.