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EXPRESS study shows significant regional differences in 1-year outcome of extremely preterm infants in Sweden
Fredrik Serenius1, Gunnar Sjörs, Mats Blennow
1Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden; Department of Pediatrics, Institute of Clinical Sciences, Umeå University, Umeå, Sweden.
Insights
Mortality rates for extremely preterm infants varied significantly across Swedish healthcare regions. Two regions showed consistently lower mortality, especially for the most immature infants, despite similar survival rates for those born at 25 weeks.
Area of Science:
- Neonatalogy
- Public Health
- Pediatric Mortality
Background:
- Extremely preterm infants (born before 27 weeks gestation) face high mortality risks.
- Significant variations in healthcare practices and outcomes exist within national healthcare systems.
Purpose of the Study:
- To investigate regional differences in mortality up to one year of age for extremely preterm infants in Sweden.
- To identify specific gestational age subgroups and time points where mortality variations are most pronounced.
Main Methods:
- National prospective observational study of extremely preterm infants born in Sweden between 2004-2007.
- Comparison of mortality rates across seven Swedish healthcare regions.
- Calculation of crude and adjusted odds ratios with 95% confidence intervals.
Main Results:
- Regional differences in perinatal mortality were observed for infants born at 22-26 weeks gestation.
- Stillbirth, perinatal, and 365-day mortality rates varied significantly for infants born at 22-24 weeks.
- Two healthcare regions demonstrated consistently lower mortality rates for extremely preterm infants.
- No significant differences in 365-day mortality were found for infants born at 25 weeks or those alive at 12 hours.
Conclusions:
- Mortality rates for extremely preterm infants vary considerably between Swedish healthcare regions.
- The most significant regional disparities in mortality are observed in the most immature infants (22-24 weeks gestation).
- Regional variations in perinatal practices may contribute to observed differences in infant mortality.
Aim:
The aim of this study was to investigate differences in mortality up to 1 year of age in extremely preterm infants (before 27 weeks) born in seven Swedish healthcare regions.
Methods:
National prospective observational study of consecutively born, extremely preterm infants in Sweden 2004-2007. Mortality was compared between regions. Crude and adjusted odds ratios and 95% CI were calculated.
Results:
Among 844 foetuses alive at mother's admission for delivery, regional differences were identified in perinatal mortality for the total group (22-26 weeks) and in the stillbirth and perinatal and 365-day mortality rates for the subgroup born at 22-24 weeks. Among 707 infants born alive, regional differences were found both in mortality before 12 h and in the 365-day mortality rate for the subgroup (22-24 weeks) and for the total group (22-26 weeks). The mortality rates were consistently lower in two healthcare regions. There were no differences in the 365-day mortality rate for infants alive at 12 h or for infants born at 25 weeks. Neonatal morbidity rates among survivors were not higher in regions with better survival rates. Perinatal practices varied between regions.
Conclusion:
Mortality rates in extremely preterm infants varied considerably between Swedish healthcare regions in the first year after birth, particularly between the most immature infants.
