Hospitalizations, Emergency Room Visits and Adherence Among Patients With Schizophrenia Initiated on Long-Acting Injectable Versus Oral Antipsychotics: A Systematic Review and Meta-Analysis

Long-acting injectable (LAI) antipsychotics, compared with oral antipsychotics (OA), have the potential to increase medication adherence in adult patients with schizophrenia. This increased adherence is hypothesized to translate into better patient outcomes, including fewer hospitalizations and emergency room (ER) admissions. While multiple studies have compared adherence and relapse rates between patients with schizophrenia treated with LAI versus OA in the real world, there is no recent synthesis of these studies. Therefore, a systematic review of the literature was conducted. MEDLINE was searched for peer-reviewed, real-world studies (i.e., retrospective or pragmatic designs) published in English between 1/1/2010 and 2/10/2020. Comparative studies reporting hospitalizations, ER visits or adherence in adults with schizophrenia treated with LAI versus OA (or pre- versus post-LAI initiation) were retained. Random-effects meta-analyses were conducted among eligible studies. Among the publications that met the inclusion criteria, 19 provided sufficient information for inclusion in the meta-analyses. Compared with patients treated on OA, patients initiated on LAI had lower odds of hospitalization (odds ratio [OR]=0.63, 95% confidence interval [CI]=0.55;0.72, n=7 studies), fewer hospitalizations per patient per year (PPPY, weighted mean difference [WMD]=-0.32 PPPY, 95%CI=-0.43;-0.22, n=8 studies) and fewer ER visits PPPY (WMD=-0.48 PPPY, 95%CI=-0.81;-0.15, n=6 studies). Patients initiated on LAI also had higher odds of being adherent to their medication (proportion of days covered ≥80%; OR=1.57, 95%CI=1.37;1.80, n=14 studies). Taken together, these findings provide additional evidence on the potential benefit of LAI compared with OA for the treatment of schizophrenia in the real world, across multiple studies.