Rapid effectiveness of intravenous ketamine for ultraresistant depression in a clinical setting and evidence for baseline anhedonia and bipolarity as clinical predictors of effectiveness

  • Author / Creator
    Thomas, Rejish
  • Background
    Intravenous ketamine has been established as an efficacious and safe treatment, with transient effect, for treatment-resistant depression. However, the effectiveness of intravenous ketamine in non-research settings and with ultraresistant depression patients remains understudied.
    This study aimed to measure the response and remission rates in ultraresistant depression patients in a clinical setting by means of a retrospective, open label, database study. Secondarily, the study investigated previous findings of clinical predictors of effectiveness with intravenous ketamine treatment in an ultraresistant depression population.
    Fifty patients with ultraresistant depression were treated between May 2015 and December 2016, inclusive, in two community hospitals in Edmonton using six ketamine infusions of 0.5mg/kg over forty minutes over two to three weeks. Data were collected retrospectively from inpatient and outpatient charts. Statistical analysis to investigate clinical predictors of effectiveness included logistic regression analysis using a dependent variable of a 50% reduction in rating scale score at any point during treatment.
    The average treatment resistance was severe at baseline, with a Maudsley Staging Method for treatment-resistant depression score of 12.1/15, and an average Beck Depression Inventory score of 34.2. Ninety percent of patients were resistant to electroconvulsive therapy. The response rate to intravenous ketamine was 44% and remission rate was 16%. As a single predictor, moderate or severe anhedonia at baseline predicted a 55% increased likelihood of response. As a combined predictor, moderate or severe anhedonia at baseline with a diagnosis of bipolar depression predicted a 73% increased likelihood of response.
    In a clinical setting, intravenous ketamine showed effectiveness in a complex, severely treatment-resistant, depressed population on multiple medication profiles concurrently. This study gave support to anhedonia and bipolar depression as clinical predictors of effectiveness.

  • Subjects / Keywords
  • Graduation date
    Fall 2018
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.