Abstract
Background: Among the most intense adversity experiences for infants is premature birth. Early birth marks the beginning of a life course that broadly affects families, healthcare, education, social systems, and the survivors themselves. For many, the transition to adulthood is challenging and often hampered by cognitive, physical and mental health, and motor and independence difficulties.
Objectives: The aim of this study was to share a comprehensive protocol of a 10th follow-up study of premature infants in their 30s. The protocol accounts for stress during the neonatal period, the cumulative context (risk and protection) of development, biological and epigenetic mechanisms, and individual resilience.
Methods: The prospective, five-group longitudinal design includes 215 term-born and preterm-born individuals with various neonatal morbidities at ages 30-35 years. Adult outcomes include health, adaptive, executive function, work, and social competence. Novel measures are four system indicators of allostatic load (AL) and epigenetics. Contextual measures include socioeconomic risk and individual resilience. All measures were selected based on coherence with constructs of the scientific aims, strong psychometrics, continuity for repeated measures, and minimal subject burden. Objective assessments include body composition imaging, exercise testing, blood and saliva collection, and actigraphy. The two-phase protocol takes approximately 8 hours.
Discussion: After an 11-month COVID-19 pause, participant response has been strong. As of May 2022, 75 participants have completed the full protocol, and 99 have consented to participate. When socioeconomic risk is controlled, we hypothesize that life course trajectories in physical and psychological health, adaptive function, and executive function will differ between term and preterm neonatal morbidity groups. AL will vary across groups and contribute to outcomes. We expect proximal protection and resilience to mediate the cumulative medical and socioeconomic risk and AL. Epigenome-wide DNA methylation, with estimates of age acceleration, will be examined across groups and explored in longitudinal associations with medical risk, socioeconomic status, and protection. To our knowledge, this is the only U.S. study of premature infants aged 30-35 years. With millions of preterm-born individuals reaching adulthood, the protocol incorporates molecular and genetic biomarkers in a life course developmental examination to inform the timing and content of interventions.