3 - Avoidable neonatal deaths of moderate and late preterm infants without congenital anomalies in a middle-income country: a population-based study

Poster Number: 3
Publication Number: 3.337

Maria Fernanda B. Almeida, Universidade Federal de Sao Paulo, Sao Paulo, Sao Paulo, Brazil; Adriana Sanudo, Federal University of São Paulo, São Paulo, Sao Paulo, Brazil; Kelsy C. Areco, Federal University of São Paulo, São Paulo, Sao Paulo, Brazil; MILTON H. MIYOSHI, unifesp, São Paulo, Sao Paulo, Brazil; Daniela T. Costa-Nobre, Universidade Federal de São Paulo - UNIFESP, São Paulo, Sao Paulo, Brazil; Mandira D. Kawakami, Federal University of Sao Paulo, Sao Paulo, Sao Paulo, Brazil; Rita Balda, Universidade Federal de Sao Paulo, São Pailo, Sao Paulo, Brazil; Ana Silvia Marinonio, Universidade Federal de São Paulo, São Paulo, Sao Paulo, Brazil; Tulio Konstantyner, Universidade Federal de São Paulo, São Paulo, Sao Paulo, Brazil; Paulo Bandiera-Paiva, Universidade Federal de São Paulo, São Paulo, Sao Paulo, Brazil; Rosa V. Freitas, Fundação Seade, São Paulo, Brasil, Sao Paulo, Brazil; Lilian C. Morais, Fundação Seade, São Paulo, Sao Paulo, Brazil; Monica La Porte Teixeira, Fundação Seade, São Paulo, Sao Paulo, Brazil; Bernadette C. Waldvogel, UFMG, São Paulo, Sao Paulo, Brazil; Carlos Roberto Kiffer, UNIFESP EPM, São Paulo, Sao Paulo, Brazil; Ruth Guinsburg, Universidade Federal de São Paulo, São Paulo, Sao Paulo, Brazil

Background: Often overlooked because of their size when compared to very preterm infants, moderate and late preterm newborns are vulnerable because of physiological and structural immaturity. In Brazil, they comprise around 85% of babies born less than 37 weeks of gestation. There is limited data on the mortality of these infants in middle-income countries.

Objective: To analyze, in preterm infant with 32-36 weeks gestation, the temporal trend of neonatal mortality during a 12-year period and the main characteristics associated with these deaths, in São Paulo State, Brazil.

Design/Methods: Population based study of live births and deaths from 0-27 days in 2004-2015 of livebirths s with 32-36 weeks gestation without congenital anomalies. The database was built by deterministic linkage of the Death and Birth Certificates. More than 99% of São Paulo State births occur in hospitals. Prais-Winsten model was applied to analyze the annual trend of the neonatal mortality rate. Maternal and neonatal characteristics associated to neonatal death was evaluated by multivariate Poisson regression with robust variance. Main causes of death were classified according to ICD-10 codes in any line of the death certificate as infection, respiratory distress, perinatal asphyxia or other. Time to death according to these causes was analyzed by Kaplan-Meier.

Results: Among 7,317,611 live births in the study period, 546,606 infants with 32-36 weeks gestation without congenital anomalies were included and 5,782 died from 0-27 days. Mortality rate decreased from 16.4 in 2004 to 7.6 per 1000 live births in 2015 (Figure 1). Prais-Winsten model showed annual decrease of 7.47% (95%CI: 6.35 to 8.58%) in the neonatal mortality rate. Multivariate analysis of factors associated with neonatal death is shown in Figure 2. During the study period, infection, respiratory problems and asphyxia were responsible, respectively for 44%, 27% and 14% of the 5,782 deaths. Median time to death was 168h when the main cause was infection, 53h for respiratory causes and 24h for asphyxia (Figure 3).Conclusion(s): Although the neonatal mortality rate of infants 32-36 weeks gestation without congenital anomalies decreased significantly over the study period, the rate is still very high. Causes of death are largely avoidable. Social disadvantage, quality of prenatal and delivery care and neonatal practices are associated with these avoidable deaths in the state with the best economic indicators in Brazil.

FAPESP Grant: # 2017/03748-7; Agreement Fundação SEADE and EPM-Unifesp: #23089.004297/2008-11 e #23089.000057/2014-95
Figure 1: Neonatal mortality rate according to year of birth of preterm infants with 32-36 weeks gestation without congenital anomalies. São Paulo State, Brazil, 2004-2015.
Figure 2: Variables associated with neonatal death according to Poisson multivariate regression and adjusted by year and marital status. São Paulo State, Brazil, 2004-2015.