# Five-Year Survival Analysis and Causes of Late Deaths of Infants Admitted to the Tertiary Newborn Intensive Care in Latvia

## TL;DR

This study examines the five-year survival rates and causes of late deaths in infants admitted to a tertiary NICU in Latvia, finding higher mortality in both premature and term infants.

## Contribution

The study provides novel insights into long-term outcomes and late mortality causes in NICU infants in Latvia.

## Key findings

- 143 (7.1%) of NICU infants died before 5 years of age.
- Premature infants had lower five-year mortality (0.9%) compared to term infants (3.2%).
- Common causes of late deaths included congenital heart disease and chromosomal abnormalities.

## Abstract

Background and Objectives: Studies on long-term survival following admission to neonatal intensive care units (NICUs) are scarce. The aim of this study was to analyse the epidemiology, five-year survival, and causes of late death of infants admitted to the only tertiary NICU in Latvia. Materials and Methods: The study population included all newborns admitted to the Children’s Clinical University Hospital (CCUH) NICU from 1 January 2013 to 31 December 2017. The unique national identity numbers from the infants or their mothers were used to link the CCUH electronic medical records to the Medical Birth Register and the Database of Causes of Death of Inhabitants of Latvia maintained by The Centre for Disease Prevention and Control of Latvia. Results: During the study period, a total of 2022 patients were treated in the tertiary NICU. The average admission rate was 18.9 per 1000 live births per year. One hundred and four patients (5.1%) died in the tertiary NICU before hospital discharge. A total of 131 (6.5%) patients from the study cohort died before 12 months of age and 143 (7.1%) before 5 years of age. Patients with any degree of prematurity had a lower five-year mortality (0.9%, 9 out of 994 discharged alive) than term infants (3.2%, 30 out of 924 discharged alive; p < 0.001). Of the 39 patients who died after discharge from the NICU, the most common causes of death were congenital heart disease 35.9% (n = 14), multiple congenital malformations and chromosomal abnormalities 17.9% (n = 7), cerebral palsy 10.3% (n = 4), and viral infections 7.7% (n = 3). Conclusions: We observed increased mortality up to five years following NICU admission in both premature and term infants. These findings will help to guide the NICU follow-up programme.