Lithium treatment may prevent suicide-related events in patients with bipolar disorder
The use of lithium treatment appears to be effective in patients with bipolar disorder with suspected suicidal intentions, according to a recent study. However, risk for suicide is only one of the many considerations when providing clinical care.
Researchers utilized within-individual designs in a register-based longitudinal cohort to examine the associations of lithium and valproate, the most common alternative to lithium, with the risk of suicide-related events and potential differences between the two drugs. They followed 51,535 individuals with bipolar disorder from 2005 to 2013 through linkage of several Swedish national registers.
Hazard ratios (HRs) of suicide-related events during treated vs untreated periods were estimated using stratified Cox regression. The population attributable fractions were also estimated to evaluate the public health impact for patients with bipolar disorder.
A total of 10,648 suicide-related events occurred during follow-up. Lithium treatment significantly reduced the incidence rate by 14 percent (HR, 0.86; 95 percent CI, 0.78 to 0.95), but valproate treatment did not (HR, 1.02; 0.89 to 1.15).
There was a statistically significant difference in HRs of suicide-related events between lithium and valproate. Based on estimates of the population attributable fraction, administering lithium during the entire follow-up could have prevented 12 percent (4 to 20 percent) of suicide-related events.
“Conclusions regarding lithium’s antisuicidal effect for bipolar disorder have been limited due to nonrepresentative subjects and potential confounding factors, including varying severity of illness,” according to researchers. “Findings regarding the effect of valproate … are inconsistent for suicidal behaviour.”