Ketamine Combined With Psychotherapy as a Treatment for Resistant Depression in a Public European Hospital

Depression affects around 280 million people worldwide, and about 30% of patients have treatment-resistant depression. Ketamine has significant scientific evidence supporting its use as an antidepressant, making it a promising approach for treatment-resistant cases. Combining ketamine with psychotherapy may enhance therapeutic response and support longer-lasting cognitive and behavioral change. This pilot proof-of-concept study aims to evaluate the effect of treatment with ketamine infusion combined with psychological intervention in a sample of nine patients with treatment-resistant depression at a general hospital within the Portuguese National Health Service.

Clinical outcomes were measured through the clinical interview and the patient health questionnaire (PHQ-9) to assess complete or partial improvement.

Following eight weeks of treatment, all showed a reduction in their PHQ-9 scores, with the median score transitioning from a baseline categorization of "severe" depression to a "moderate" level. It was found that 44.4% (4/9) of participants showed a response to treatment (≥ 50% reduction in the PHQ-9 score). Among the patients with suicidal ideation, slightly over half showed remission of these thoughts at the end of treatment. Among the participants subsequently monitored as outpatients, only 29% (2/7) experienced a deterioration in mood within three months post-treatment, requiring an adjustment of antidepressant therapy.

In our study, an improvement in depressive symptoms was observed, despite their severity, in a sample submitted to multiple previous pharmacological strategies.This retrospective study evaluated ketamine infusions combined with psychotherapy in nine patients with treatment-resistant depression at a general hospital. After eight weeks, all participants improved, with PHQ-9 scores shifting from severe to moderate. Overall, 44% responded to treatment, and among those with suicidal ideation, more than half showed remission.