title: Psychopathology in a Swedish population of school children with tic disorders.
abstract: OBJECTIVE
  To examine patterns of psychiatric comorbid disorders and associated problems in a school population of children with tic disorders.
  
  
  METHODS
  From a total population of 4,479 children, 25 with Tourette's disorder (TD), 34 with chronic motor tics (CMT), 24 with chronic vocal tics (CVT), and 214 with transient tics (TT) during the past year were found. A three-stage procedure was used: tic screening, telephone interview, and clinical assessment. The TD group was compared with 25 children with TT and 25 controls without tics.
  
  
  RESULTS
  Psychiatric comorbid disorders were found in 92% of the children with TD. Attention-deficit/hyperactivity disorder was most common, and patterns of psychiatric comorbidity were similar in children with TD and CVT, but not with CMT and TT. Aggressive behavior was more common in children with TD than other tic disorders.
  
  
  CONCLUSIONS
  Psychiatric comorbid disorders are common even in community-based samples of children with TD and CVT. TD and CVT seem to be part of the same disease entity, with TD being a more severe form. Chronic tics may be a marker for behavioral and learning difficulties in children, and awareness of these associations is critical to the care and treatment of children with tics.
authors.affiliation: Drs. Khalifa and Von Knorring are with the Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Najah
authors.initials: N
authors.lastname: Khalifa
authors.affiliation: Drs. Khalifa and Von Knorring are with the Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Anne-Liis
authors.initials: AL
authors.lastname: VON Knorring
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology*; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology*; D011599:Psychopathology; D013334:Students; D013548:Sweden; D013981:Tic Disorders / Q000453:epidemiology* / Q000523:psychology*