Retinopathy of Prematurity: Incidence and Risk Factors at Muhimbili National Hospital Dar es Salaam, Tanzania

Abstract

Background: Retinopathy of prematurity (ROP) is a vasoproliferative retinal disorder affecting premature newborns. It is one of the leading causes of preventable childhood blindness. In Tanzania, improvement in neonatal care has led to increased survival of preterm babies. However, data on the incidence and risk factors for ROP are scarce. Aim: This study was done to determine the incidence and risk factors associated with ROP among preterm babies at Muhimbili National Hospital. Methods: A prospective cohort study was conducted among 193 preterm newborns of gestational age (GA) ≤34 weeks and birth weight (Bwt) ≤2000g as well as those with unstable clinical course from June 2020 to February 2021. ROP screening entailed a dilated fundus examination using an indirect ophthalmoscope. Cumulative incidence was determined as the proportion of babies clinically diagnosed with ROP by the end of the study period. Risk factors associated with ROP were analyzed. P value of <0.05 was considered statistically significant. Results The cumulative incidence of ROP was 29% (56/193) and severe ROP incidence of 8.8% (17/193). Majority of infants with ROP had stage two 41.1% and zone two disease 73.2%.Also, 8.93% had aggressive posterior retinopathy of prematurity. Multivariate analysis revealed 6 factors as significant independent predictors of ROP occurrence, GA less than 32weeks with hazard ratio (HR) 6.8 and p value 0.000), Bwt less than 1500 (2.1, 0.021), Apgar score less than 7 (1.9, 0.029), RDS (3.3, 0.013), oxygen supplementation for more than a week (0.74, 0.034) and Intraventricular hemorrhage (9.7, 0.001). Surfactant use had a protective role with HR of 0.2 and p value of 0.027. Conclusion ROP incidence is relatively high at MNH. Screening is essential to prevent visual morbidity and blindness that may result from the disease