Ketamine for treatment resistant depression in individuals with eating disorders: a comparison study

Abstract

Individuals with eating disorders (EDs) have an increased risk of treatment resistant depression (TRD) and treatment resistant bipolar disorder (TRBD) and a higher rate of suicidal ideation and death by suicide than individuals without EDs. Individuals with EDs are less responsive to conventional treatments for mood disorders than individuals without EDs. Ketamine has evidence for treatment of TRD and TRBD and for the treatment of acute suicidality. Ketamine has also been shown to be safe in individuals with EDs who are malnourished. This study is among the first to examine the efficacy of ketamine in TRD and TRBD in patients with co-occurring EDs at higher levels of care. Participants were 85 adults admitted to an ED treatment facility who received subanesthetic intranasal generic ketamine compared to a sample of 85 adults matched for age, sex, gender, race, diagnosis, and level of care at admission admitted to the same facilities who did not receive ketamine. Participants completed the Eating Disorder Examination Questionnaire (EDE-Q), Patient Health Questionnaire-9 (PHQ-9), suicidal ideation (PHQ-9 Item 9) and Generalized Anxiety Disorder-7 (GAD-7) at admission and discharge. Patients receiving ketamine and matched controls were not significantly different on age, sex, gender, race, diagnosis, or level of care at admission. There were no significant differences between groups on admission for all EDE-Q subscales, PHQ-9, suicidal ideation, or GAD. All patients, irrespective of use of ketamine, improved significantly from admission to discharge on all outcomes. There were no significant differences between groups for change in all EDE-Q subscales, change in PHQ-9, change in suicidal ideation, or change in GAD-7. Patients receiving ketamine had significantly longer lengths of stay than controls (b = 0.39, p = .01). The lack of significant differences was maintained irrespective of predicting raw change, controlling for admission scores, or additionally controlling for length of stay. In a population of individuals seeking higher level of care for an ED and controls matched for age, gender, sex, diagnosis, level of care, and race, treatment with ketamine was associated with significant reductions in depression and ED severity, but not more so than individuals not treated with ketamine. Findings from the study suggest that ketamine may be a viable treatment option for individuals with EDs, however, further research is needed to determine ketamine’s efficacy in treating EDs with comorbid depression. Individuals with eating disorders have an increased risk of having treatment resistant depressive symptoms. Many people who have eating disorders (ED) and depression do not respond to conventional medications and psychotherapy for their depressive symptoms. Ketamine, at lower than anesthetic doses, is a unique antidepressant medication that works rapidly to relieve symptoms of depression and suicidality. It has not been studied how ketamine would impact depressive symptoms for people who have EDs and treatment resistant depression. In this study, it was shown that individuals who are in a higher level of care treatment for an ED and treated with ketamine and a control group not treated with ketamine both showed improvements in their symptoms of depression and suicidal ideation to a similar degree. In addition, both groups showed improvements in their ED symptom scores. This is important information for individuals with EDs and the providers who treat them who are considering subanesthetic ketamine as an option for treating ED symptoms and with comorbid treatment resistant depression or treatment resistant bipolar depression.