Real-world effectiveness of repeated ketamine infusions for treatment resistant depression during the COVID-19 pandemic.

• 107 adults with treatment-resistant depression (TRD) received intravenous (IV) ketamine during the COVID-19 pandemic. • Compared to 160 adults who were treated in a time-matched period from 2019 to 2020, improvements in depressive symptoms, suicidality, anxiety, and functioning did not significantly differ. • Treatment response did not appear to be associated with the COVID-19 pandemic, despite possible increased loneliness and social isolation. Herein we evaluate the impact of COVID-19 restrictions on antidepressant effectiveness of intravenous (IV) ketamine in adults with treatment-resistant depression (TRD). We conducted a case series analysis of adults with TRD (n = 267) who received four ketamine infusions at an outpatient clinic in Ontario, Canada, during COVID-19 restrictions (from March 2020 - February 2021; n = 107), compared to patients who received treatment in the previous year (March 2019 - February 2020; n = 160). Both groups experienced significant and comparable improvements in depressive symptoms, suicidal ideation, and anxiety with repeated ketamine infusions. Effectiveness of IV ketamine was not attenuated during the COVID-19 period. [ABSTRACT FROM AUTHOR]