Suicidal risk in bipolar I disorder patients and adherence to long-term lithium treatment

Objectives:  Among the well-established treatments for bipolar disorder (BPD), lithium continues to offer an unusually broad spectrum of benefits that may include reduction of suicidal risk.
Methods:  We examined the association of suicidal acts with adherence to long-term lithium maintenance treatment and other potential risk factors in 72 BP I patients followed prospectively for up to 10 years at a Mood Disorders Research Center in Spain.
Results:  The observed rates of suicide were 0.143, and of attempts, 2.01%/year, with a 5.2-fold (95% CI: 1.5–18.6) greater risk among patients consistently rated poorly versus highly adherent to lithium prophylaxis (11.4/2.2 acts/100 person-years). Treatment non-adherence was associated with substance abuse, being unmarried, being male, and having more hypomanic–manic illness and hospitalizations. Suicidal risk was higher with prior attempts, more depression and hospitalization, familial mood disorders, and being single and younger, as well as treatment non-adherence, but with neither sex nor substance abuse. In multivariate analysis, suicidal risk was associated with previous suicidality > poor treatment adherence > more depressive episodes > younger age.
Conclusions:  The findings support growing evidence of lower risk of suicidal acts during closely monitored and highly adherent, long-term treatment with lithium and indicate that treatment adherence is a potentially modifiable factor contributing to antisuicidal benefits.