Mortality, attempted suicide, re-hospitalisation and prescription refill for clozapine and other antipsychotics in Sweden-a register-based study

Pharmacoepidemiol Drug Saf. 2014 Mar;23(3):290-8. doi: 10.1002/pds.3567. Epub 2014 Jan 17.

Abstract

Purpose: The aim of this study was to analyse prescription refill, re-hospitalisation, total mortality, mortality because of suicide and attempted suicide among patients who were taking various types of antipsychotics.

Methods: A population-based cohort study analysed all patients (n=26046) in Sweden who had been treated for schizophrenia from 2006 to 2009 with regard to re-hospitalisation and prescription refill for various types of antipsychotic treatment. A case-control study nested within the cohort analysed all-cause mortality, mortality because of suicide and attempted suicide in relation to antipsychotic use. The study adjusted for history of hospitalisation for psychiatric and medical care, attempted suicide and use of antidepressants.

Results: Aripiprazole users were the only ones who showed significantly lower all-cause risks of death, but so few events occurred among users of this relatively new drug that the results should be interpreted with caution. Clozapine users showed lower odds of death by suicide (odds ratio [OR]=0.45 [95%CI 0.20-0.98]) and of attempted suicide (OR=0.44 [0.28-0.70]) than haloperidol users after adjustment for age, sex and year of discharge. Olanzapine users showed approximately the same favourable pattern. Patients who used clozapine were most likely to refill prescriptions and had lower rates of re-hospitalisation. Only one death and 23 cases of agranulocytosis were reported compared with 223 suicides and 831 suicide attempts. An etiologic fraction calculation suggests that the use of clozapine rather than traditional drugs could have prevented 95 suicide attempts during the period.

Conclusion: Clozapine and olanzapine reduce the risk of suicide, attempted suicide and re-hospitalisation.

Keywords: antipsychotics; epidemiology; mortality; pharmacoepidemiology; re-hospitalisation; suicide; suicide attempts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antipsychotic Agents / administration & dosage*
  • Case-Control Studies
  • Clozapine / administration & dosage*
  • Cohort Studies
  • Drug Prescriptions*
  • Female
  • Hospitalization* / trends
  • Humans
  • Male
  • Middle Aged
  • Mortality / trends
  • Suicide, Attempted / prevention & control*
  • Suicide, Attempted / psychology
  • Sweden / epidemiology
  • Young Adult

Substances

  • Antipsychotic Agents
  • Clozapine