title: The influence of comorbid disorders on the episodicity of bipolar disorder in youth.
abstract: OBJECTIVE
  Bipolar disorder (BP) frequently co-occurs with other psychiatric disorders. We examine whether course of anxiety disorders (ANX), attention deficit hyperactivity disorder (ADHD), disruptive behavior disorders (DBD), and substance use disorders (SUD) influence likelihood of recovery and recurrence of depression and mania in BP youth.
  
  
  METHODS
  Weekly ratings of psychiatric disorder intensity were obtained from 413 participants of the Course and Outcome of BP Youth project, followed for an average of 7.75 years. Multiple-event Cox proportional hazards regression analyses examined worsening of comorbid disorders as predictors of mood episode recovery and recurrence.
  
  
  RESULTS
  Increased severity in ANX and SUD predicted longer time to recovery and less time to next depressive episode, and less time to next manic episode. Multivariate models with ANX and SUD found that significant effects of ANX remained, but SUD only predicted longer time to depression recovery. Increased severity of ADHD and DBD predicted shorter time to recurrence for depressive and manic episodes.
  
  
  CONCLUSIONS
  There are significant time-varying relationships between the course of comorbid disorders and episodicity of depression and mania in BP youth. Worsening of comorbid conditions may present as a precursor to mood episode recurrence or warn of mood episode protraction.
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA.|Butler Hospital, Providence, RI, USA.
authors.forename: S
authors.initials: S
authors.lastname: Yen
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA.|Pacific Institute for Research and Evaluation, Pawtucket, RI, USA.
authors.forename: R
authors.initials: R
authors.lastname: Stout
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA.
authors.forename: H
authors.initials: H
authors.lastname: Hower
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Killam
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA.|Butler Hospital, Providence, RI, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Weinstock
authors.affiliation: VA Boston Healthcare System and Harvard Medical School, Cambridge, MA, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Topor
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA.|Emma Pendleton Bradley Hospital, East Providence, RI, USA.
authors.forename: D P
authors.initials: DP
authors.lastname: Dickstein
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, USA.|Emma Pendleton Bradley Hospital, East Providence, RI, USA.
authors.forename: J I
authors.initials: JI
authors.lastname: Hunt
authors.affiliation: Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: M K
authors.initials: MK
authors.lastname: Gill
authors.affiliation: Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: T R
authors.initials: TR
authors.lastname: Goldstein
authors.affiliation: Centre for Youth Bipolar Disorder, University of Toronto Medical Center, Toronto, ON, Canada.
authors.forename: B I
authors.initials: BI
authors.lastname: Goldstein
authors.affiliation: Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: N D
authors.initials: ND
authors.lastname: Ryan
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA.
authors.forename: M
authors.initials: M
authors.lastname: Strober
authors.affiliation: Department of Child and Adolescent Psychiatry, Institute of Psychiatry, King's College London, London, UK.
authors.forename: R
authors.initials: R
authors.lastname: Sala
authors.affiliation: Department of Psychiatry, Nationwide Children's Hospital and Ohio State College of Medicine, Columbus, OH, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Axelson
authors.affiliation: Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
authors.forename: B
authors.initials: B
authors.lastname: Birmaher
authors.affiliation: Butler Hospital, Providence, RI, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Keller
mesh_terms: D000293:Adolescent; D001008:Anxiety Disorders / Q000523:psychology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000523:psychology*; D019958:Attention Deficit and Disruptive Behavior Disorders / Q000523:psychology*; D001714:Bipolar Disorder / Q000523:psychology*; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D000066553:Problem Behavior; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D019966:Substance-Related Disorders / Q000523:psychology*
keywords: bipolar disorder; child and adolescent psychiatry; comorbidity