title: Incident users of antipsychotics: who are they and how do they fare?
abstract: OBJECTIVE
  In Denmark, as well as in many other countries, consumption of antipsychotics is on the rise, partly due to increasing off-label use. The aim of this study was to analyze and quantify the extent of off-label use and polypharmacy in incident users of antipsychotic medication, and to examine initial antipsychotic prescribing patterns and associated use of mental health care services.
  
  
  METHODS
  Population-based cohort study linking the following Danish national registers: the Central Psychiatric Research Register, the Register of Medicinal Product Statistics, and Statistics Denmark.
  
  
  RESULTS
  From 2007 to 2012, 154,351 Danish subjects initiated treatment with antipsychotics. Among these, 71,254 (46 %) subjects had a psychiatric diagnosis recorded. The most frequent diagnoses were reaction to severe stress and adjustment disorders (10,106; 14 %), depressive episode (8876; 12 %), and recurrent depressive disorder (6810; 10 %). We found high antipsychotic discontinuation rates during the first few months (45 % in 4 months) and frequent antidepressant co-prescribing from treatment onset (47 %). Significantly greater likelihood of psychiatric hospitalization was observed for antipsychotic polypharmacy (HR 1.38; 95 % CI 1.32-1.45), whereas antipsychotic discontinuation was associated with decreased hospitalization risk in most off-label conditions.
  
  
  CONCLUSIONS
  The brief duration of most antipsychotic prescriptions suggests that antipsychotics are prescribed more liberally than recommended. As a consequence of the range of adverse effects associated with antipsychotic drug use, the documented widespread off-label prescribing practices warrant careful monitoring for adverse effects and prompt discontinuation in case of an unfavorable risk-benefit ratio.
authors.affiliation: Center for Neuropsychiatric Schizophrenia Research and Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research, Mental Health Center Glostrup, Copenhagen University Hospital, Nordre Ringvej 29-67, 2600, Glostrup, Denmark. lone.baandrup@regionh.dk.
authors.forename: Lone
authors.initials: L
authors.lastname: Baandrup
authors.affiliation: Center for Health Economics Research, University of Southern Denmark, 5230, Odense, Denmark.
authors.forename: Marie
authors.initials: M
authors.lastname: Kruse
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D003718:Denmark; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000188:drug therapy*; D008605:Mental Health Services / Q000706:statistics & numerical data*; D008875:Middle Aged; D056687:Off-Label Use / Q000706:statistics & numerical data*; D019338:Polypharmacy; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012042:Registries; D018570:Risk Assessment
chemical_list: D014150:Antipsychotic Agents
keywords: Antipsychotics; Off-label; Prescribing practice; Register-based