Lithium is associated with decrease in all-cause and suicide mortality in high-risk bipolar patients: A nationwide registry-based prospective cohort study

J Affect Disord. 2015 Sep 1:183:159-65. doi: 10.1016/j.jad.2015.04.055. Epub 2015 May 8.

Abstract

Background: Mortality rates, in particular due to suicide, are especially high in bipolar patients. This nationwide, registry-based study analyses the associations of medication use with hospitalization due to attempted suicides, deaths from suicide, and overall mortality across different psychotropic agents in bipolar patients.

Method: Altogether 826 bipolar patients hospitalized in Finland between 1996-2003 because of a suicide attempt were followed-up for a mean of 3.5 years. The relative risk of suicide attempts leading to hospitalization, completed suicide, and overall mortality during lithium vs. no-lithium, antipsychotic vs. no-antipsychotic, valproic acid vs. no-valproic acid, antidepressant vs. no-antidepressant and benzodiazepine vs. no-benzodiazepine treatment was measured.

Results: The use of valproic acid (RR=1.53, 95% CI: 1.26-1.85, p<0.001), antidepressants (RR=1.49, 95% CI: 1.23-1.8, p<0.001) and benzodiazepines (RR=1.49, 95% CI: 1.23-1.80, p<0.001) was associated with increased risk of attempted suicide. Lithium was associated with a (non-significantly) lower risk of suicide attempts, and with significantly decreased suicide mortality in univariate (RR=0.39, 95% CI: 0.17-0.93, p=0.03), Cox (HR=0.37, 95% CI: 0.16-0.88, p=0.02) and marginal structural models (HR=0.31, 95% CI: 0.12-0.79, p=0.02). Moreover, lithium was related to decreased all-cause mortality by 49% (marginal structural models).

Limitations: Only high-risk bipolar patients hospitalized after a suicide attempt were studied. Diagnosis was not based on standardized diagnostic interviews; treatment regimens were uncontrolled.

Conclusions: Maintenance therapy with lithium, but not with other medications, is linked to decreased suicide and all-cause mortality in high-risk bipolar patients. Lithium should be considered for suicide prevention in high-risk bipolar patients.

Keywords: Attempted suicide; Bipolar; Lithium; Mortality; Suicide.

MeSH terms

  • Adult
  • Aged
  • Antidepressive Agents / therapeutic use*
  • Bipolar Disorder / drug therapy*
  • Bipolar Disorder / epidemiology
  • Cohort Studies
  • Female
  • Finland / epidemiology
  • Humans
  • Lithium Compounds / therapeutic use*
  • Male
  • Middle Aged
  • Proportional Hazards Models
  • Prospective Studies
  • Psychotropic Drugs / therapeutic use
  • Registries*
  • Suicide / statistics & numerical data
  • Suicide Prevention*

Substances

  • Antidepressive Agents
  • Lithium Compounds
  • Psychotropic Drugs