Age and antisuicidal effect of lithium
Leo Sher, M.D.
Our research work, “Antisuicidal effect of lithium in bipolar patients: Is there an age-specific effect?” has been published in the Journal of Affective Disorders online ahead of print (1).
The age-related antisuicidal effect of lithium and valproate was compared in ninety-four (n = 94) high-risk bipolar suicide attempters. Individuals with bipolar disorder and at least one past suicide attempt who were in a depressed or mixed state were recruited into a 2.5-year randomized, double-blind trial.
We found that age significantly moderated the effect of lithium vs. valproate on the risk of suicide event during the study. We observed that those who were 42 years or older (above the 75th percentile), and on lithium had significantly lower risk of suicidal behavior than older patients on valproate (>42 years) or younger (<42 years) patients on either medication. This difference in risk differences was not explained away by age-related differences in the proportion of participants with bipolar II disorder or higher lethality of past suicide attempts in younger participants; neither was there any correlation with age in the longitudinally measured blood lithium levels or valproate levels.
In summary, bipolar patients randomized to lithium and older than 42 years had less suicidal behavior compared to same aged patients on valproate or younger patients (< 42 years) on either medication. This effect was independent of clinical and sociodemographic characteristics.
Reference
- Dervic K*, Sher L*, Galfalvy HC, Grunebaum M, Burke AK, Sullivan G, Sublette ME, Mann JJ, Oquendo MA. Antisuicidal effect of lithum in bipolar patients: Is there an age-specific effect? J Affect Disord. 2023 Aug 22;341:8-11. doi: 10.1016/j.jad.2023.08.107. Epub ahead of print.
*These two authors contributed equally.