Prior studies report conflicting results about the association between lithium use and all-cause mortality. In addition, data are scarce on this association among older adults with psychiatric disorders. In this report, we sought to examine the associations of lithium use with all-cause mortality and specific causes of death (i.e., due to cardiovascular disorder, non-cardiovascular disease, accident, or suicide) among older adults with psychiatric disorders during a 5-year follow-up period.
In this observational epidemiological study, we used data from 561 patients belonging to a Cohort of individuals with Schizophrenia or Affective disorders aged 55-years or more (CSA). Patients taking lithium at baseline were first compared to patients not taking lithium, and then to patients taking (i) antiepileptics and (ii) atypical antipsychotics in sensitivity analyses. Analyses were adjusted for socio-demographic (e.g., age, gender), clinical characteristics (e.g., psychiatric diagnosis, cognitive functioning), and other psychotropic medications (e.g. benzodiazepines).
There was no significant association between lithium use and all-cause mortality [AOR=1.12; 95%CI=0.45-2.79; p=0.810] or disease-related mortality [AOR=1.37; 95%CI=0.51-3.65; p=0.530]. None of the 44 patients taking lithium died from suicide, whereas 4.0% (N=16) of patients not receiving lithium did.
These findings suggest that lithium may not be associated with all-cause or disease-related mortality and might be associated with reduced risk of suicide in this population. They argue against the underuse of lithium as compared with antiepileptics and atypical antipsychotics among older adults with mood disorders.