Original Article Early Emergence of Delayed Social Competence in Infants Born Late and Moderately Preterm Samantha Johnson, PhD, CPsychol, AFBPsS,* Ruth Matthews, MSc,* Elizabeth S. Draper, PhD,* David J. Field, DM,* Bradley N. Manktelow, PhD,* Neil Marlow, DM, FMedSci,† Lucy K. Smith, PhD,* Elaine M. Boyle, MD, PhD* ABSTRACT: Objective: To assess behavioral outcomes and social competence at 2 years of age in infants born late and moderately preterm (LMPT; 32–36 wk gestation). Method: One thousand one hundred and thirty LMPT infants and 1255 term-born (‡37 wk) controls were recruited at birth to a prospective geo- graphical population-based study. Parents completed the Brief Infant and Toddler Social Emotional Assessment (BITSEA) at 2 years corrected age to assess infants’ behavior problems and social competence. Cognitive development was assessed using the Parent Report of Children’s Abilities-Revised. Parent questionnaires at 2 years were completed for 638 (57%) LMPT and 765 (62%) term-born infants. Group differences in the prevalence of behavior problems and delayed social competence between LMPT infants and term-born controls were adjusted for age, sex, small-for-gestational-age, socioeconomic status and cognitive impairment. Results: Late and moderately preterm infants were at significantly increased risk of delayed social competence compared with term-born controls (26.4% vs 18.4%; adjusted-relative risk [RR] 1.28; 95% CI, 1.03–1.58), but there was no significant group difference in the prevalence of behavior problems (21.0% vs 17.6%; adjusted-RR 1.13, 0.89–1.42). Non-white ethnicity (RR 1.68, 1.26–2.24), medium (RR 1.60, 1.14–2.24) and high (RR 1.98, 1.41–2.75) socioeconomic risk and recreational drug use during pregnancy (RR 1.70, 1.03–2.82) were significant independent predictors of delayed social competence in LMPT infants. Conclusion: Birth at 32 to 36 weeks of gestation confers a specific risk for delayed social competence at 2 years of age. This may be indicative of an increased risk for psychiatric disorders later in childhood. (J Dev Behav Pediatr 36:690–699, 2015) Index terms: preterm, outcomes, behavior problems, social competence, infant. It is well documented that very preterm birth, before 32 weeks of gestation, is associated with lifelong neu- rodevelopmental sequelae. There is increasing interest in the development of psychopathology in preterm pop- ulations and growing evidence of a significant excess of behavior problems and psychiatric disorders among very preterm survivors compared with their term-born peers. The preterm behavioral phenotype is characterized by inattention, anxiety, and sociocommunicative problems, which manifest in an increased risk for attention deficit/ hyperactivity disorders, emotional disorders and autism spectrum disorders in childhood. 1 Signs of future dis- orders are evident in infancy and persist throughout childhood and adolescence. Over recent years, there has been growing interest in the outcomes of children born late (34–36 wk) and moderately (32–33 wk) preterm. Although historically considered low risk, accumulating evidence shows that infants born at these gestations are at increased risk for neurodevelopmental delay, cognitive deficits, and learn- ing difficulties compared with term-born peers. To date, the few studies of behavioral outcomes in this pop- ulation have produced conflicting results, and there is a paucity of prospective population-based studies. Whilst a number of authors have reported an increased risk of socioemotional and attention problems in school-aged children born late and/or moderately preterm, the prevalence of externalizing problems typically shows no difference from term-born controls. 2–6 However, the authors of one study have reported an increased risk of problems in all behavioral domains in preschoolers born moderately preterm, 7 whereas others have reported no significant differences from term-born controls. 8 Several From the *Department of Health Sciences, University of Leicester, Leicester, United Kingdom; †Department of Academic Neonatology, Institute for Wom- en’s Health, University College London, London, United Kingdom. Received May 2015; accepted August 2015. This article presents independent research funded by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research (PGfAR) Programme (Grant Reference Number RP-PG-0407–10029). The views expressed are those of the author(s) and not necessarily those of the National Health Service (NHS), the NIHR or the Department of Health. N. Marlow receives a proportion of funding from the Department of Health’s NIHR Biomedical Re- search Centres funding scheme at UCLH/UCL. Disclosure: The authors declare no conflict of interest. Address for reprints: Samantha Johnson, PhD, CPsychol, AFBPsS, Department of Health Sciences, University of Leicester, 22-28 Princess Rd West, Leicester, LE1 6TP, United Kingdom; e-mail: sjj19@le.ac.uk. Copyright Ó 2015 Wolters Kluwer Health, Inc. All rights reserved. 690 | www.jdbp.org Journal of Developmental & Behavioral Pediatrics Copyright © 201 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. 5