title: Comorbid social withdrawal (hikikomori) in outpatients with social anxiety disorder: clinical characteristics and treatment response in a case series.
abstract: BACKGROUND
  Severe social withdrawal (called hikikomori, and defined as isolation lasting more than six months and not due to an apparent mental disorder) has drawn increasing public attention in Japan. It is unclear whether hikikomori is merely a symptom or syndrome of social withdrawal.
  
  
  OBJECTIVE
  To evaluate this phenomenon in relationship to social anxiety disorder (SAD), as few previous studies have.
  
  
  METHODS
  One hundred and forty-one consecutive patients with SAD diagnosed according to DSM-IV criteria by a semi-structured interview were treated with a combination of psychotherapy, pharmacotherapy and group activity.
  
  
  RESULTS
  Twenty-seven (19%) SAD patients fulfilled the criteria for hikikomori, and these patients had earlier onset, more symptoms and less education than non-hikikomori SAD patients. Only 33% of hikikomori SAD patients spontaneously complained of SAD symptoms at first visit. There were no diagnostic differences between hikikomori and non-hikikomori SAD patients, except that comorbid obsessive-compulsive disorder was more frequent in hikikomori SAD patients. Functional impairment in 10 (37%) hikikomori SAD patients improved after several years of combination therapy.
  
  
  CONCLUSIONS
  Hikikomori may serve as a proxy for a severe form of SAD. Patients with comorbid SAD and hikikomori have lower treatment response rates than those with SAD alone.
authors: Department of Neuropsychiatry, Osaka City University Graduate School of Medicine, Abunoku, Osaka, Japan. toshi@med.osaka-cu.ac.jp
authors: Toshihiko
authors: T
authors: Nagata
authors: Hisashi
authors: H
authors: Yamada
authors: Alan R
authors: AR
authors: Teo
authors: Chiho
authors: C
authors: Yoshimura
authors: Takenori
authors: T
authors: Nakajima
authors: Irene
authors: I
authors: van Vliet
mesh_terms: D000293:Adolescent; D000328:Adult; D014151:Anti-Anxiety Agents / Q000627:therapeutic use; D015928:Cognitive Behavioral Therapy; D003131:Combined Modality Therapy; D015897:Comorbidity; D003521:Cyclopropanes / Q000627:therapeutic use; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D016666:Fluvoxamine / Q000627:therapeutic use; D006801:Humans; D007406:Interview, Psychological; D007564:Japan; D008297:Male; D000078764:Milnacipran; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology / Q000628:therapy; D017374:Paroxetine / Q000627:therapeutic use; D010698:Phobic Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology / Q000628:therapy*; D011615:Psychotherapy, Group; D019962:Reactive Attachment Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology / Q000628:therapy*; D012189:Retrospective Studies; D012934:Social Isolation / Q000523:psychology*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014151:Anti-Anxiety Agents; D003521:Cyclopropanes; D017374:Paroxetine; D000078764:Milnacipran; D016666:Fluvoxamine