Comparative risks of all-cause mortality for Veterans with schizophrenia with ongoing receipt of clozapine and other antipsychotic medications.

To guide care for patients with schizophrenia, the Veterans Health Administration (VHA) evaluated the associations between current or recent use of clozapine and all-cause mortality and explored associations for other antipsychotic medications. Using a case-control design, patients with schizophrenia who died in fiscal years 2014-2018 were matched on age, sex, race, and VHA facility to up to 10 controls who were alive on the case's date of death (index date). Medication coverage during the 91 days before the index date was classified as none, partial (1-44 days), and consistent (45-91 days). Medication coverage patterns during the index period were compared to coverage patterns during the period of 92-182 days prior to index date with each medication coverage classified as no change, no coverage, increased, or decreased. Conditional logistic regression analyses controlling for patient characteristics identified no associations of consistent or increasing clozapine coverage with mortality; partial and decreasing coverage were associated with greater mortality and these effects did not differ from those of other the medications considered. Exploratory analyses considering non-clozapine antipsychotic agents suggest that consistent coverage by olanzapine may be associated with increased mortality, that mortality associated with olanzapine may be greater than aripiprazole, and that this effect can be attributed primarily to patients with diabetes. Further study of this topic is needed.