Impact of the COVID-19 pandemic on morbidity and mortality in a Spanish cohort of very-preterm/very-low-birth weight newborns

Abstract

Introduction: During the COVID-19 pandemic, neonatal intensive care units (NICUs) modified their care practices, applying stricter hygiene protocols and limiting the presence of parents in NICUs. The impact of these measures on infant health remains unclear. The aim was the evaluation of the effect of the COVID-19 pandemic on mortality and major morbidity rates in very-preterm/very-low-birth weight infants of Spain.

Methods: Data were obtained from the Spanish Neonatal Network SEN1500. The study period ran from January 2016 to December 2022 and it was divided in three periods: pre-COVID-19, COVID-19, and post-COVID-19.

Results: This cohort study included 15,976 patients. In the post-COVID-19 versus the pre-COVID 19 and COVID-19 periods, we observed significantly lower incidence of respiratory distress syndrome (48.8 % vs. 52.6 % vs. 53 %; p = 0.005), patent ductus arteriosus (22.3 % vs. 23.8 % vs. 26.2 %; p < 0.001); and late-onset sepsis (18.7 % vs. 25.1 % vs. 20.9 %; p < 0.001). The use of antenatal steroids did not differ significantly across periods. Post-COVID-19, the incidence of early-onset sepsis (3 % vs. 4.3 %; p = 0.013) and necrotizing enterocolitis (3.9 % vs. 5.6 %; p = 0.004) was lower than pre-COVID-19. No such differences were observed between post-COVID-19 and COVID-19 periods. Over the entire study period, the overall mortality rate continued its downward trend, with no differences in the main causes of death.

Conclusions: The COVID-19 pandemic had no apparent negative effect on mortality in the Spanish cohort of preterm infants. Increased awareness of infection transmission and stricter hygiene policies may improve medical management and reduce late-onset sepsis and other morbidities that can be triggered by infectious factors in high-risk populations.

Keywords: Mortality; Necrotizing enterocolitis; Pandemic; Patent ductus arteriosus; Preterm; Sepsis.