title: Antipsychotics-induced tardive syndrome: a retrospective epidemiological study.
abstract: OBJECTIVE
  Only little information of the epidemiology of tardive syndrome in patients using antipsychotics is available. Herein, we aimed to investigate the prevalence and risk factors of antipsychotics-induced tardive syndrome.
  
  
  METHODS
  This study was conducted by means of a retrospective survey. Subjects receiving antipsychotics for more than 6 months, but no other agents that may cause involuntary movements, were consecutively recruited. Tardive syndrome was evaluated in every included subject. Possible confounding medical conditions were carefully ruled out.
  
  
  RESULTS
  Of the 123 included subjects, 35 (28.5%) were found to have at least 1 episode of tardive syndrome. The prevalence of subtypes of tardive syndrome were as follows: tardive dyskinesia, 21.1%; tardive dystonia, 12.5%; tardive tremor, 2.4%; and tardive akathisia, 2.4%. Concurrent physical illness and a history of extrapyramidal symptoms were significant risk factors for tardive syndrome.
  
  
  CONCLUSIONS
  This study showed that antipsychotics may induce various types of tardive syndrome, of which tardive dyskinesia is the most predominant one. Physicians should be aware of this common and distressing adverse effect when using antipsychotics.
authors.affiliation: Departments of *Psychiatry and Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine; †Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan; and ‡Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine.
authors.forename: Min-Jing
authors.initials: MJ
authors.lastname: Lee
authors.forename: Pao-Yen
authors.initials: PY
authors.lastname: Lin
authors.forename: Yung-Yee
authors.initials: YY
authors.lastname: Chang
authors.forename: Mian-Yoon
authors.initials: MY
authors.lastname: Chong
authors.forename: Yu
authors.initials: Y
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000188:drug therapy; D008875:Middle Aged; D009069:Movement Disorders / Q000453:epidemiology* / Q000209:etiology*; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D014150:Antipsychotic Agents