The impact of COVID-19 public health measures on the utilization of antipsychotics in schizophrenia in Manitoba - A population-based study

Purpose: During the COVID-19 pandemic, public health measures were implemented, yet it is unknown whether these measures affected medication access in those with schizophrenia (SCZ). This study aimed to assess whether the antipsychotic utilization in SCZ changed during the pandemic. Methods: We used dispensed prescription drug data from the Canadian province of Manitoba in individuals with SCZ using linked administrative data from the Manitoba Population Research Data Repository. The quarterly incident and prevalent dispensation of antipsychotics at two periods were compared with the expected trend (April 1, 2015 to April 1, 2020 and 2021) using linear autoregression. We stratified the primary results by age and sex and examined multiple subgroups. Results: There were 9045 individuals with SCZ in the first fiscal quarter of 2020. The prevalent use of the most common antipsychotics were: olanzapine (206.7/1000), risperidone (190.8/1000), quetiapine (174.4/1000), and clozapine (100.9/1000). The overall prevalent use of antipsychotics remained stable during the pandemic compared with the expected trend. A significant decrease in the incident use in April-June 2020 (estimate:-1.3, 95%CI:-2.2,-0.3) was noted compared with the expected. A significantly higher incidence of atypical antipsychotics (estimate: 1.4, 95%CI: 0.2,2.5) and risperidone separately (estimate: 1.8, 95%CI: 0.2,3.3) was noted in 2021 compared with expected. Conclusion: This study found a decline in the receipt of antipsychotics for people with SCZ during the initial implementation of COVID-19 public health measures, particularly on the overall incidence. Future work on investigating the impact of these trends on SCZ outcomes is needed to inform future pandemic-related policies.