Clozapine utilization at the United States Veterans Health Administration: a descriptive report of prescribing patterns and patient characteristics among Operation Enduring Freedom/Operation Iraqi Freedom Veterans

Int Clin Psychopharmacol. 2020 Nov;35(6):322-328. doi: 10.1097/YIC.0000000000000330.

Abstract

To identify the clozapine utilization rate at Veterans Health Administration, as well as patient characteristics, and correlates of use to garner a better understanding of the Veterans Health Administration-treated clozapine population. A longitudinal retrospective cohort analysis was conducted on all Operation Enduring Freedom/Operation Iraqi Freedom Veterans treated with clozapine prescriptions through Veterans Health Administration from 2006 to 2016. Descriptive and inferential analyses were conducted. The sample of 1.3 million veterans had 15 416 with schizophrenia-spectrum disorders, however; only 197 filled outpatient clozapine prescriptions through Veterans Health Administration, a clozapine utilization rate of 1.28%. Median days on clozapine were 305. Median number of antipsychotic medications was 12, with a median rank of clozapine being the eighth antipsychotic trialed. 59.90% of individuals had at least one period of maintenance clozapine treatment. The median number of psychiatric hospitalizations was four, and Clozapine rank was strongly associated with number of hospitalizations. There were no associations between acute versus maintenance clozapine use and either hospitalizations or mortality. Clozapine utilization was very low relative to recommended prescribing rates. Delayed initiation of clozapine was noted and was associated with increased number of hospitalizations. Lack of observed differences in mortality may be explained by low number of mortalities.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Afghan Campaign 2001-*
  • Antipsychotic Agents / therapeutic use
  • Clozapine / therapeutic use*
  • Drug Prescriptions / statistics & numerical data*
  • Female
  • Humans
  • Iraq War, 2003-2011*
  • Male
  • Middle Aged
  • Retrospective Studies
  • Schizophrenia / drug therapy
  • United States
  • United States Department of Veterans Affairs
  • Veterans Health / statistics & numerical data*

Substances

  • Antipsychotic Agents
  • Clozapine