Perinatal Anemia is Associated with Neonatal and Neurodevelopmental Outcomes in Infants with Moderate to Severe Perinatal Asphyxia.

BACKGROUND

Perinatal anemia may cause perinatal asphyxia. Its pathophysiology and neurodevelopmental effects are theoretically different from other causes of perinatal asphyxia.

OBJECTIVE

The study aimed to determine whether perinatal anemia results in different short-term and long-term outcomes than other causes of perinatal asphyxia treated with therapeutic hypothermia.

METHODS

We retrospectively included infants with moderate to severe hypoxic-ischemic encephalopathy, born between May 2009 and October 2015. During follow-up, we assessed cognitive and motor development at 2-3 years of age, using the Bayley Scales of Infant and Toddler Development, third edition (BSID-III). Neurodevelopmental outcome (NDO) was classified as abnormal in case of cerebral palsy with Gross Motor Function Classification System ≥III and/or a BSID-III composite score < 85. Outcomes of infants with perinatal anemia (initial hemoglobin < 7 mmol/L) were compared to infants born with perinatal asphyxia due to other causes.

RESULTS

In total, 111 infants were included of whom 30 infants (27%) died during the neonatal period. Infants with anemia (n = 23) had a higher mortality risk, OR 3.33, 95% CI 1.27-8.72, p = 0.01. None of the surviving infants with anemia (n = 12) had an abnormal NDO, in contrast to 26/69 (38%) with neurodevelopmental impairments, particularly motor problems, in the non-anemic group, p < 0.01.

CONCLUSIONS

Perinatal anemia causing moderate to severe perinatal asphyxia is associated with a higher risk for neonatal mortality. All survivors with perinatal anemia, however, showed a normal NDO in contrast to children who were born asphyxiated due to other causes. The underlying pathophysiological mechanism for the favorable NDO in the perinatal anemia group needs further elucidation.