Behavioral Patterns in Adolescents Born at 23 to 25 Weeks of Gestation.

Background: This study examined mental health outcomes in extremely preterm children (EPT) born at 23 to 25 weeks of gestation between 1992 and 1998 at 2 Swedish tertiary care centers that offered regional and active perinatal care to all live-born EPT infants.

Methods: We assessed 132 (98%) of the 134 EPT survivors at 10 to 15 years of age alongside term-born controls. Behavioral and emotional problems were evaluated by using Achenbach's Child Behavior Checklist and Teacher Report Form and Conners' Parent and Teacher scales for attention-deficit/hyperactivity disorder.

Results: Parents and teachers reported significantly more problems with internalizing behaviors as well as attention, social, and thought problems in EPT children than in controls, even when those with major neurodevelopmental disabilities (NDDs) were excluded. Multivariate analysis of covariance of the behavioral problems reported by parents and teachers revealed no interactions, but significant main effects emerged for group status (EPT versus control) and sex, with all effect sizes being medium to large and accounting for 8% to 14% of the variance. Compared with the controls, EPT children without NDDs had significantly increased rates of ≥90th percentile for total Conners' attention-deficit/hyperactivity disorder problem scores (parents: 40% vs 15%, odds ratio: 3.7, < .001) (teachers: 24% vs 9%, odds ratio: 3.3, = .005). The corresponding rates were higher in the total population.

Conclusions: EPT children with or without NDDs had behavioral problems characterized by a higher risk for anxiety and attention, social, and thought problems. These findings further strengthen the proposition that a preterm behavioral phenotype is recognizable in adolescents born EPT.