Understanding the course of attention deficit hyperactivity disorder in children born after a threatened preterm labor: a 6-year cohort study

Abstract

[EN] BACKGROUND: Recent research suggests that children born after suspected preterm labor may observe a potential cluster with different attention deficit hyperactivity disorder features, depending on the time of birth. However, the evolution of symptoms and their predictors remain unknown in this population. OBJECTIVE: This study aimed to examine the trajectories of attention deficit hyperactivity disorder symptoms of children born after suspected preterm labor, between ages 2 and 6 years, considering prematurity condition and comparing with controls. In addition, this study aimed to find potential modifiable predictors of evolution to enhance prognosis. STUDY DESIGN: In this prospective cohort study, 119 mother-child pairs who experienced suspected preterm labor and 60 controls were included. Patients were divided according to prematurity condition in full term (n=27), late preterm (n=55), and very preterm (n=37). Attention deficit hyperactivity disorder symptoms were assessed at ages 2 and 6 years. The association between potential modifying factors (group, time of assessment, sex, birthweight percentile, maternal history of trauma, maternal anxiety at diagnosis, and maternal anxiety during the children's assessments) and disorder trajectories was assessed by adjusting the Bayesian mixed linear models. All analyses were performed in R (version 4.3.0; R Foundation for Statistical Computing, Vienna, Austria). RESULTS: An interaction emerged between time and group, with late-preterm neonates born after suspected preterm labor being the only group to improve from ages 2 to 6 years (-2.26 points in Conners scale per percentile decrease and 0.98 probability of effect). Another interaction between time and maternal anxiety at postnatal time assessments intensified over time (0.07 and 0.84). Predictors of symptom severity included lower weight percentile at birth (-0.2 and 0.96), male sex (-2.99 and <0.99), higher maternal anxiety at diagnosis (+0.08 and 0.99), and maternal history of trauma (+0.23 and 0.98). CONCLUSION: Unlike very-preterm and full-term children, those born late preterm showed an improvement over time, probably because late-preterm children do not carry the sequelae derived from severe prematurity but benefit from close monitoring. As maternal psychopathology emerged as a determinant modifier of course and severity, it is crucial to develop targeted psychological interventions for pregnant individuals and reevaluate monitoring programs for their offspring, regardless of prematurity.