Medication and suicide risk in schizophrenia: a nested case-control study

Schizophr Res. 2013 Nov;150(2-3):416-20. doi: 10.1016/j.schres.2013.09.001. Epub 2013 Oct 2.

Abstract

Introduction: Patients with schizophrenia are at increased risk of suicide, but data from controlled studies of pharmacotherapy in relation to suicide risk is limited.

Aim: To explore suicide risk in schizophrenia in relation to medication with antipsychotics, antidepressants, and lithium.

Methods: Of all patients with a first clinical discharge diagnosis of schizophrenia or schizoaffective disorder in Stockholm County between 1984 and 2000 (n=4000), patients who died by suicide within five years from diagnosis were defined as cases (n=84; 54% male). Individually matched controls were identified from the same population. Information on prescribed medication was retrieved from psychiatric records in a blinded way. Adjusted odds ratios [OR] of the association between medication and suicide were calculated by conditional logistic regression.

Results: Lower suicide risk was found in patients who had been prescribed a second generation antipsychotic (clozapine, olanzapine, risperidone, or ziprasidone; 12 cases and 20 controls): OR 0.29 (95% confidence interval [CI], 0.09-0.97). When the 6 cases and 8 controls who had been prescribed clozapine were excluded, the OR was 0.23 (95% CI 0.06-0.89). No significant association was observed between suicide and prescription of any antipsychotic, depot injection antipsychotics, antidepressants, SSRI, or lithium.

Conclusions: Lower suicide risk for patients who had been prescribed second generation antipsychotics may be related to a pharmacological effect of these drugs, to differences in adherence, or to differences in other patient characteristics associated with lower suicide risk.

Keywords: Antidepressant drugs; Antipsychotic drugs; Case–control study; Lithium; Schizophrenia; Suicide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Antidepressive Agents / adverse effects
  • Antipsychotic Agents / adverse effects*
  • Case-Control Studies
  • Female
  • Humans
  • Lithium Chloride / adverse effects
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Odds Ratio
  • Risk
  • Schizophrenia / drug therapy*
  • Schizophrenic Psychology*
  • Self-Injurious Behavior / chemically induced*
  • Sex Factors
  • Suicide / psychology*
  • Young Adult

Substances

  • Antidepressive Agents
  • Antipsychotic Agents
  • Lithium Chloride