Adherence and persistence to long-acting injectable dopamine receptor blocking agent therapy in the United States: A systematic review and meta-analysis of cohort studies

Time-to-therapy discontinuation in patients newly diagnosed with schizophrenia initiated on long-acting injectable versus oral dopamine receptor blocking agents

AIM

The purpose of this project is to assess the time-to-therapy discontinuation and hospital readmission rate among patients newly diagnosed with schizophrenia who are prescribed long-acting injectable versus oral dopamine receptor blocking agents.

METHODS

A retrospective review of medical records was performed for adult patients admitted to an 80-bed inpatient behavioural health facility with a new diagnosis of schizophrenia. The primary outcome studied was time to therapy discontinuation within 1 year of discharge, while secondary outcomes assessed were time-to-therapy discontinuation within 90 days and readmission rate at 30-days, 6 months, and 1 year. Multivariate Cox proportional hazard and linear regression modelling were used for statistical analysis.

RESULTS

A total of 425 patients were included in the analysis, with 66.4% (n = 282) discharged on oral and 33.6% (n = 143) on long-acting injectable dopamine receptor blocking agents. At 1 year post-discharge, the rates of discontinuation were 49.7% for those prescribed long-acting injectable and 55.7% for those prescribed oral formulations (adjusted hazard ratio = 0.54, p = .012). There was no statistically significant difference in readmission rate between the patients prescribed long-acting injectable and oral dopamine receptor blocking agents at any timepoint tested.

CONCLUSIONS

The use of long-acting injectable dopamine receptor blocking agents was associated with longer time-to-discontinuation compared to oral agents when prescribed to patients newly diagnosed with schizophrenia in the inpatient setting. However, this was not associated with significant reductions in rehospitalization, calling into question the clinical impact. Future studies will seek to confirm these findings using a prospective study design.

A 10-year mirror-image study of effectiveness and cost of long-acting paliperidone palmitate injectable in patients with schizophrenia or schizoaffective disorder

Acute episodes of Schizophrenia and Schizoaffective Disorder often require hospitalizations and/or psychiatry emergency room (PER) visits, with significant economic burden. Long-acting injectables (LAI), such as the once-monthly Palmitate Paliperidone LAI (1MPP) are effective in suppressing symptoms and raise treatment adherence. This study is the first aimed at evaluating long-term efficacy of initiation of 1MPP. This was a mirror-image study with a total 10 year observational length. Sample was divided into five different groups according to time span of observation: 2,4,6,8, and 10 years. Number of participants per group was 162, 129, 95, 77 and 35, respectively. Main outcomes were number and length of hospitalizations and number of PER visit. Significant reductions in these outcomes after initiation of 1MPP were found in all groups. Subgroups consisting only of patients with full adherence were evaluated, and these had better outcomes. A cost evaluation was also performed, which demonstrated decreases every year, for all main outcomes. Sensitivity analysis in the 2-year group showed results in this time-frame are independent of gender, diagnosis, previous LAI or 1MPP initiation setting. Initiation of 1MPP reduces number and length of hospitalizations up to 5 years, decreasing associated costs. This study increases evidence supporting use of 1MPP in patients with Schizophrenia or Schizoaffective disorder.