title: Differences between prepubertal- versus adolescent- onset bipolar disorder in a Spanish clinical sample.
abstract: OBJECTIVE
  To examine patients attended and diagnosed with bipolar disorder (BD) at a child and adolescent psychiatry service; to record age of diagnosis and age of onset, and to study clinical differences between prepubertal and adolescent onset groups.
  
  
  METHODS
  All patients currently attended for BD type I, type II or non specified BD were reviewed and divided into two age groups: prepubertal onset (beginning before age 13) and adolescent onset (beginning at or above age 13).
  
  
  RESULTS
  The sample were 43 patients with BD. Fourteen (32.6%) with prepubertal onset and 29 (67.4%) with adolescent onset. Time between onset of symptoms and diagnosis was longer in the prepubertal onset group (1.2 years versus 0.8 years respectively, P = .05). Patients with prepubertal onset BD more frequently presented previous symptoms such as irritability and conduct problems and had a higher rate of comorbidity (more frequently attention-deficit/hyperactivity disorder-ADHD). The adolescent onset group more often presented psychotic symptoms.
  
  
  CONCLUSIONS
  The clinical characteristics of patients with bipolar disorder differ according to whether onset is prepubertal or adolescent.
authors.affiliation: Child and Adolescent Psychiatry and Psychology Department, Clinical Institute of Neurosciences, Hospital Clínic Universitari of Barcelona, C/Villarroel, 170, Barcelona, 08036, Spain. llazaro@clinic.ub.es
authors.forename: Luisa
authors.initials: L
authors.lastname: Lázaro
authors.forename: Josefina
authors.initials: J
authors.lastname: Castro-Fornieles
authors.forename: José Eugenio
authors.initials: JE
authors.lastname: de la Fuente
authors.forename: Immaculada
authors.initials: I
authors.lastname: Baeza
authors.forename: Astrid
authors.initials: A
authors.lastname: Morer
authors.forename: Montserrat
authors.initials: M
authors.lastname: Pàmias
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D001714:Bipolar Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology* / Q000628:therapy; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D017678:Sex Distribution; D013030:Spain / Q000453:epidemiology