Population based study on the outcome of small for gestational age newborns
- 1Perinatal Epidemiology Infectious Diseases Unit, Departments of Pediatrics and Obstetrics, Hannover Medical School, Hannover, Germany
- 2Department of Biometry, Epidemiology and Information Processing, WHO Centre for Research and Training in Veterinary Public Health, School of Veterinary Medicine Hannover, Hannover
- 3Neuroepidemiology Unit, Department of Neurology, Children’s Hospital and Harvard Medical School of Public Health, Boston, Massachusetts 02115, USA
- 4Centre for Quality Management in Health Care, Hannover
- 5Department of Neonatology, University of Tübingen, Tübingen, Germany
- Correspondence to:
Department of Neonatology, University Hospital Tübingen, Calwerstr 7, D-72076 Tübingen, Germany;
- Accepted 8 September 2004
Objective: To explore whether and how population based data from a regional quality control programme can be used to investigate the hypothesis that small for gestational age (SGA) very low birthweight infants (VLBW, <1500 g) are at increased risk of death, severe intraventricular haemorrhage (IVH), and periventricular leucomalacia (PVL), but at decreased risk of respiratory distress syndrome (RDS).
Methods: Analyses of population based perinatal/neonatal data (1991–96) from a quality control programme in Lower Saxony, Germany. After assessment of data validity and representativeness, exclusion criteria were defined: birth weight >90th centile, severe malformations, siblings of multiple births, and gestational age (GA) <25 or >29 weeks. Outcomes of interest were death, severe IVH, PVL, and RDS. Multivariable analyses were performed by Cox proportional hazard and logistic regression models.
Results: Within the data validation procedure, an increase in proportions of both VLBW (from 0.95% in 1991 to 1.11% in 1996; +17%) and SGA (from 22.7% to 27.4%; +21%) infants became apparent (p<0.05). The study population consisted of 1623 infants (173 SGA). Mortality was 12.1% (n = 196), with an adjusted hazard ratio for SGA infants of 2.54, 95% confidence interval (CI) 1.70 to 3.79. Both groups were at similar risk of severe IVH (adjusted odds ratio 0.93, 95% CI 0.5 to 1.65) and PVL (1.54, 95% CI 0.78 to 2.87), but SGA infants had less RDS (0.57, 95% CI 0.35 to 0.93). Male sex, multiple birth, hypothermia (<35.5°C), and sepsis were associated with IVH and RDS. Infants admitted to hospitals with <36 VLBW admissions/year had increased mortality (adjusted hazard ratio 1.56, 95% CI 1.12 to 2.18).
Conclusions: SGA VLBW infants are at increased risk of death, but not of IVH and PVL, and at decreased risk of RDS. That mortality is higher in smaller hospitals needs further investigation.
- AGA, appropriate size for gestational age
- GA, gestational age
- IVH, intraventricular haemorrhage
- LGA, large for gestational age
- NICU, neonatal intensive care unit
- PVL, periventricular leucomalacia
- RDS, respiratory distress syndrome
- SGA, small for gestational age
- VLBW, very low birthweight
- intraventricular haemorrhage
- periventricular leucomalacia
- respiratory distress syndrome
- small for gestational age
Competing interests: none declared