4CPS-138 An observational retrospective study on treatment adherence of long acting injectable antipsychotics

Background and importanceTreatment with long acting injectable (LAI) antipsychotics has been shown to improve treatment adherence compared with oral antipsychotics, but it is still controversial if adherence is modified with the use of polytherapy with oral and LAI antipsychotics.Aim and objectivesTo evaluate treatment adherence (monotherapy with LAI antipsychotics versus polytherapy with LAI and oral antipsychotics) in patients with different psychiatric disorders.Material and methodsAn observational retrospective study was developed, and two cohorts of patients were defined regarding their antipsychotic therapy: (1) monotherapy with LAI antipsychotics and (2) polytherapy with oral and LAI antipsychotics. Patients who began treatment with LAI antipsychotics before 2016 were included in this study. Adherence to treatment was examined during the year 2018, based on the electronic registration of LAI antipsychotic administrations and oral antipsychotic withdrawals at the pharmacy offices. Optimal adherence was defined as 100% of prescriptions withdrawals or 100% of the doses of LAI antipsychotics administered.ResultsA total of 73 patients were included (39 with monotherapy, 34 with polytherapy), with a mean age of 57.1 years. The most prevalent diagnosis was schizophrenia (49.3%), followed by delusional disorder (17.8%) and personality disorder (11.0%). No significant differences were found for sociodemographic data between the groups. Adherence to LAI antipsychotics was 97.3% in the monotherapy group and 87.1% in the polytherapy group, with no significant difference between the two groups (p=0.187). Adherence to oral antipsychotics was 63.7%.Conclusion and relevanceAdherence to treatment was suboptimal in both groups, but lower in patients receiving polytherapy with oral and LAI antipsychotics. Treatment adherence decreased as treatment complexity increased, as seen in previous literature.References and/or acknowledgementsNo conflict of interest.