Objective

Extremely low birth weight children are at high risk for cognitive impairment.

Study design

Cognitive outcome of extremely low birth weight children participating in a Neonatal Research Network, randomized trial was evaluated at 18 and 30 months corrected age using the Bayley Scales of Infant Development, 2nd ed. Family resources and social support were assessed using a Family Resource Scale parent questionnaire. Regression analysis was used to determine independent demographic, medical, and family resource factors influencing longitudinal cognitive outcome.

Result

Higher Family Resource Scale scores at 18 months were associated with greater improvement in cognitive scores between 18 and 30 months. Cognitive outcome was most adversely affected in children whose families had the least resources and social support. The adverse effect of poor social support was independent of family income.

Conclusion

Poor interpersonal social support has an independent, adverse impact on cognitive outcomes of extremely low birth weight infants.

Background

Extremely preterm (EPT) birth has been related to dysregulation of stress responses and behavioral/learning problems at school age. Early adverse experiences can blunt HPA axis reactivity. We hypothesized that an attenuated cortisol awakening response would be associated with developmental and behavioral problems at school age in EPT children.

Methods

This secondary analysis of a sub-cohort of the SUPPORT study included children born between 24 and 27 weeks, evaluated at 6-7 years with a neurodevelopmental battery and cortisol measures. Differences were tested between EPT and a term-born group. Relationships of cortisol awakening response to test scores were analyzed.

Results

Cortisol was measured in 110 EPT and 29 term-born 6-7 year olds. Unadjusted WISC-IV and NEPSY-II scores were significantly worse among EPT children only. Conners Parent Rating Scale behavior scores were significantly worse among EPT children. After adjusting for covariates, blunted cortisol awakening responses were found to be associated with poorer scores on memory tests and greater problems with inattention for the EPT group (p < 0.05) only.

Conclusions

Among children born EPT, we identified an association of blunted cortisol awakening response with memory and inattention problems. This may have implications related to stress reactivity and its relationship to learning problems in children born EPT.

Clinicaltrials

Gov id

Extended Follow-up at School Age for the SUPPORT Neuroimaging and Neurodevelopmental Outcomes (NEURO) Cohort: NCT00233324.

Impact

In children born EPT, stress reactivity may have a relationship to learning problems. Cortisol awakening response should be a component for follow-up in EPT born children. Components of executive function, such as memory and attention, are related to stress reactivity.

Objective

To estimate risk of necrotizing enterocolitis (NEC) for extremely low birth weight (ELBW) infants as a function of preterm formula (PF) and maternal milk intake and calculate the impact of suboptimal feeding on the incidence and costs of NEC.

Study design

We used aORs derived from the Glutamine Trial to perform Monte Carlo simulation of a cohort of ELBW infants under current suboptimal feeding practices, compared with a theoretical cohort in which 90% of infants received at least 98% human milk.

Results

NEC incidence among infants receiving ≥98% human milk was 1.3%; 11.1% among infants fed only PF; and 8.2% among infants fed a mixed diet (P = .002). In adjusted models, compared with infants fed predominantly human milk, we found an increased risk of NEC associated with exclusive PF (aOR = 12.1, 95% CI 1.5, 94.2), or a mixed diet (aOR 8.7, 95% CI 1.2-65.2). In Monte Carlo simulation, current feeding of ELBW infants was associated with 928 excess NEC cases and 121 excess deaths annually, compared with a model in which 90% of infants received ≥98% human milk. These models estimated an annual cost of suboptimal feeding of ELBW infants of $27.1 million (CI $24 million, $30.4 million) in direct medical costs, $563 655 (CI $476 191, $599 069) in indirect nonmedical costs, and $1.5 billion (CI $1.3 billion, $1.6 billion) in cost attributable to premature death.

Conclusions

Among ELBW infants, not being fed predominantly human milk is associated with an increased risk of NEC. Efforts to support milk production by mothers of ELBW infants may prevent infant deaths and reduce costs.