title: Do early internalizing and externalizing problems predict later irritability in adolescents with attention-deficit/hyperactivity disorder?
abstract: OBJECTIVE
  Irritable mood is common in children with attention-deficit/hyperactivity disorder. Research to date has primarily comprised cross-sectional studies; thus, little is known about the antecedents of irritability. Furthermore, existing cross-sectional studies generally focus on the association between irritability and comorbidities and do not examine broader aspects of functioning. Finally, previous research has neglected to include child-report of irritability. This study aimed to address these gaps using data from a longitudinal study of children with attention-deficit/hyperactivity disorder.
  
  
  METHODS
  Children aged 5-13 years (mean = 10.2; standard deviation = 1.9) with attention-deficit/hyperactivity disorder were recruited from pediatric practices across Victoria, Australia. This study reports on those who had reached adolescence (12 years or older, mean = 13.8; standard deviation = 1.2) at the 3-year follow-up ( n = 140). Internalizing and externalizing problems were measured using the Strengths and Difficulties Questionnaire. At follow-up, parent-reported and adolescent self-reported irritability was assessed using the Affective Reactivity Index. Parent and adolescent outcomes measured at follow-up included attention-deficit/hyperactivity disorder symptom severity, sleep, behavior and parent mental health.
  
  
  RESULTS
  Children with externalizing problems at age 10 had higher parent-reported irritability (β = 0.31, 95% confidence interval = [0.17,-0.45], p = 0.001) in adolescence. Cross-sectional analyses found that irritability was associated with increased attention-deficit/hyperactivity disorder symptom severity and sleep problems; poorer emotional, behavioral and social functioning; and poorer parent mental health.
  
  
  CONCLUSIONS
  Our findings highlight the importance of assessing for and managing early conduct problems in children with attention-deficit/hyperactivity disorder, as these predict ongoing irritability which, in turn, is associated with poorer functioning across a number of domains.
authors: 1 Centre for Community Child Health, Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC, Australia.|2 Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.
authors: Melissa
authors: M
authors: Mulraney
authors: 1 Centre for Community Child Health, Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC, Australia.|2 Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.
authors: Nardia
authors: N
authors: Zendarski
authors: 1 Centre for Community Child Health, Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC, Australia.|2 Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.
authors: Fiona
authors: F
authors: Mensah
authors: 1 Centre for Community Child Health, Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC, Australia.|2 Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.
authors: Harriet
authors: H
authors: Hiscock
authors: 1 Centre for Community Child Health, Murdoch Childrens Research Institute, The Royal Children's Hospital, Parkville, VIC, Australia.|2 Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.|3 School of Psychology, Deakin University, Burwood, VIC, Australia.
authors: Emma
authors: E
authors: Sciberras
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000523:psychology*; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007508:Irritable Mood; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D010290:Parents / Q000523:psychology*; D011788:Quality of Life; D057566:Self Report; D012720:Severity of Illness Index; D012893:Sleep Wake Disorders / Q000453:epidemiology*; D014739:Victoria
keywords: Attention-deficit/hyperactivity disorder; comorbidity; functioning; irritability