A One-Year Health Economics Study Before and After Switching from Oral Antipsychotics to Once-Monthly Paliperidone Palmitate in Patients with Schizophrenia, A Retrospective, Prospective, Mirror-Image Study

Background: Schizophrenia is ranked among the top 25 leading causes of disability worldwide in 2013 which resulting in social and economic burden. By observing patients with schizophrenia one year before and after switching from oral antipsychotics (OAPs) to once-monthly paliperidone palmitate (PP1M), we can better understand the change of total costs in schizophrenic patients, including direct costs and indirect costs, after switching treatment patterns. Methods: A total of 100 schizophrenic (ICD-10) outpatient and inpatient patients from Shandong Mental Health Center were collected from December 2016 to June 2019. Treatment modalities, health care resource utilization and costs were compared before and after switching directly from oral antipsychotics to PP1M.Results: Of the 82 patients included in the main analyses, hospitalization costs decreased was partly offset by the increase of medical costs, which causing direct costs slightly increased (t=-1.81, P＞0.05). The reduction of productivity costs (t=2.06, P＜0.05) and caregiver care costs (t=1.99, P≤0.05) was seen at post-PP1M switch, therefore the indirect costs also obviously reduced (t=2.31, P＜0.05). Total costs slightly increased (t=-0.05, P＞0.05）compared to pre-PP1M period. For patients with ≥ 1 all-cause inpatient stay in the baseline period (n=32), compared with pre-PP1M, a fewer number of inpatient stays (t=1.73, P＜0.05) and hospitalizations (t=2.56, P≤0.01) were observed and a significant reduction in direct costs (t=2.20, P＜0.01) was observed post-transition to PP1M. Conclusions: Switching to PP1M from OAPs can improve adherence to therapy and not increase the costs of health care in the clinical. Patients with ≥1 recent all-cause inpatient stay had a significant reduction in direct costs after switching from oral antipsychotics to PP1M, suggesting that patients with ≥1 all-cause inpatient stay may benefit after switching to PP1M. Indirect costs decrease from OAPs to PP1M, suggesting that reduce the burden of the family labor after switch to PP1M.