Despite improved survival of extremely premature infants in recent decades, neonatal intensive care unit (NICU) graduates are diagnosed with asthma, sleep disordered breathing (SDB) in childhood, and neurodevelopmental impairments (NDI) at significant rates, disproportionate to their term peers. Early detection and intervention are critical to mitigate the impact of these impairments. Mechanisms leading from premature birth to these undesirable outcomes remain unclear, and accurate prognostic measures are lacking.

This study wants to learn if these problems are related to certain patterns of breathing that babies had while they were in the NICU.

Asthma, SDB, and NDI are common consequences of preterm birth with significant impact on child and family quality of life and public health. To date, the mechanisms leading to these outcomes remain unclear, and improvements in neonatal care have not improved these outcomes. While early detection and intervention can reduce the burden of these outcomes, methods for early identification of infants destined for these morbidities is currently lacking. Utilizing the Pre-Vent cohort to investigate potential underlying causes and identify predictors for these conditions as we propose here is essential to inform future prevention and intervention strategies that promote optimal health and development.

Recent compelling data indicate that early postnatal intermittent hypoxemia (IH) events may play a role in undesirable outcomes. Early postnatal IH events in extremely preterm infants are associated with bronchopulmonary dysplasia (BPD), asthma medication at 2 years, and NDI at 18 months. The ability of IH to perturb maturation of long-term respiratory control has been demonstrated in neonatal rodents consistent with preterm infants being at heightened risk for childhood SDB. Although evidence is emerging that IH events are linked to poor outcomes in premature infants, the specific relationship between distinct IH patterns (e.g. duration, timing, frequency, and nadir) and longer-term respiratory and neurologic function remains to be elucidated.

Inclusion Criteria:

• Enrolled in any Institutional Review Board (IRB) protocol of the Pre-Vent Study that had signed consent, or in any IRB protocol of the Pre-Vent Study that authorized re-contact for future research
• Born <29 weeks gestational age
• Age at enrollment less than 7 years old

Exclusion Criteria:

• Subject was withdrawn from the Pre-Vent study after signing Pre-Vent consent form, for any reason
• Subject had no physiological data recorded as part of Pre-Vent
• Lack of regulatory approval from local IRB or Department of Children and Family Services (DCFS) to recontact subjects
• Adopted by non-consenting family
• Parent refused further contact, prior to approach for Post-Vent
• Infant enrolled in Pre-Vent at Washington University St Louis, which is not a Post-Vent participating site.

The study population will be drawn from surviving, previously consented children in the existing Pre-Vent study cohort or in any IRB protocol of the Pre-Vent study that authorized re-contact for future research, which was drawn from Neonatal Intensive Care Unit Populations in Chicago, IL; Cleveland, OH; Birmingham, AB; or Miami, FL, USA.

Up to 500 children will be enrolled after parent/guardian provides informed consent.

Parents, guardians or primary caretakers will act as proxies for providing information about the children.