Effect of long-acting aripiprazole monohydrate on inpatient encounters: A retrospective mirror image study

INTRODUCTION: Antipsychotics improve symptoms associated with schizophrenia and bipolar disorder. To improve medication adherence and decrease the need for hospitalization, many antipsychotics have been developed into long-acting injectable (LAI) formulations. Though mirror-image studies have demonstrated significantly decreased hospitalization rates with LAI use, there is limited data when suboptimal use parameters are present. METHODS: A retrospective chart review was conducted on patients who were administered aripiprazole monohydrate long-acting injectable (AM-LAI) in an adult mental health unit. Demographics and AM-LAI use parameters were analyzed descriptively. Endpoints compared the days between encounters pre and post AM-LAI administration and number of inpatient encounters between the 180 days pre and post AM-LAI administration. Effects of AM-LAI on inpatient encounters were analyzed using a Wilcoxon signed rank test with an alpha set to <0.05 for significance. RESULTS: Fifty-eight patients met inclusion criteria. Mean (± SD) age was 39.4 (11.4) years with 55.2% of the sample male. Most patients were diagnosed with schizophrenia or unspecified psychotic disorder and admitted involuntarily. The mean number of days from last admission to the date of initial AM-LAI administration was 109.3 (75.2), compared with 131.3 (69.8) days to next encounter (P = .044) post AM-LAI. Total inpatient encounters were also reduced (P = .004), although no differences in encounters for psychiatric reasons were detected. DISCUSSION: Use of AM-LAI was associated with a prolonged time to next inpatient encounter and reduced total inpatient encounters, however its use failed to demonstrate reductions in psychiatric encounters.