Objective: To assess the associations between neonatal hyperglycaemia and insulin treatment, versus long-term neurodevelopmental outcomes in children born extremely preterm.
Design and setting: Observational national cohort study (Extremely Preterm Infants in Sweden Study) using prospectively and retrospectively collected data. Neurodevelopmental assessment was performed at 6.5 years of age.
Patients: 533 infants born <27 gestational weeks during 2004-2007; 436 survivors were assessed at 6.5 years.
Outcome measures: Neurodevelopmental disability (NDD), survival without moderate to severe NDD, Wechsler Intelligence Scale for Children IV Full scale intelligence quotient (WISC-IV FSIQ) and Movement Assessment Battery for Children 2 (MABC-2) total score.
Results: Duration of neonatal hyperglycaemia >8 mmol/L was associated with WISC-IV scores-for each day with hyperglycaemia there was a decrease of 0.33 points (95% CI 0.03 to 0.62) in FSIQ. Neonatal hyperglycaemia >8 mmol/L occurring on 3 consecutive days was associated with lower MABC-2 scores (adjusted mean difference: -4.90; 95% CI -8.90 to -0.89). For each day with hyperglycaemia >8 mmol/L, there was a decrease of 0.55 points (95% CI 0.17 to 0.93) in MABC-2 total score. Insulin treatment was not associated with any of the outcome measures.
Conclusion: Neonatal hyperglycaemia >8 mmol/L was associated with lower intelligence scores and worse motor outcomes at 6.5 years of age. Insulin treatment was not associated with either worsened or improved neurodevelopmental outcomes. Randomised controlled trials are needed to clarify the role of insulin in treating hyperglycaemia in extremely preterm infants.