title: Behavioural symptoms of attention deficit/hyperactivity disorder in preterm and term children born small and appropriate for gestational age: a longitudinal study.
abstract: BACKGROUND
  It remains unclear whether it is more detrimental to be born too early or too small in relation to symptoms of attention deficit/hyperactivity disorder (ADHD). Thus, we tested whether preterm birth and small body size at birth adjusted for gestational age are independently associated with symptoms of ADHD in children.
  
  
  METHODS
  A longitudinal regional birth cohort study comprising 1535 live-born infants between 03/15/1985 and 03/14/1986 admitted to the neonatal wards and 658 randomly recruited non-admitted infants, in Finland. The present study sample comprised 828 children followed up to 56 months. The association between birth status and parent-rated ADHD symptoms of the child was analysed with multiple linear and logistic regression analyses.
  
  
  RESULTS
  Neither prematurity (birth < 37 weeks of gestation) nor lower gestational age was associated with ADHD symptoms. However, small for gestational age (SGA < -2 standard deviations [SD] below the mean for weight at birth) status and lower birth weight SD score were significantly, and independently of gestational age, associated with higher ADHD symptoms. Those born SGA, relative to those born AGA, were also 3.60-times more likely to have ADHD symptoms scores above the clinical cut-off. The associations were not confounded by factors implicated as risks for pregnancy and/or ADHD.
  
  
  CONCLUSIONS
  Intrauterine growth restriction, reflected in SGA status and lower birth weight, rather than prematurity or lower gestational age per se, may increase risk for symptoms of ADHD in young children.
authors.affiliation: Institute of Behavioral Science, P.O. Box 9, FI-00014 University of Helsinki, Helsinki, Finland. kati.heinonen@helsinki.fi
authors.forename: Kati
authors.initials: K
authors.lastname: Heinonen
authors.forename: Katri
authors.initials: K
authors.lastname: Räikkönen
authors.forename: Anu-Katriina
authors.initials: AK
authors.lastname: Pesonen
authors.forename: Sture
authors.initials: S
authors.lastname: Andersson
authors.forename: Eero
authors.initials: E
authors.lastname: Kajantie
authors.forename: Johan G
authors.initials: JG
authors.lastname: Eriksson
authors.forename: Dieter
authors.initials: D
authors.lastname: Wolke
authors.forename: Aulikki
authors.initials: A
authors.lastname: Lano
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology / Q000523:psychology*; D002648:Child; D005260:Female; D005387:Finland / Q000453:epidemiology; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature / Q000523:psychology*; D007236:Infant, Small for Gestational Age / Q000523:psychology*; D008137:Longitudinal Studies; D008297:Male; D011247:Pregnancy; D012307:Risk Factors