Association between depression subtypes and response to repeated-dose intravenous ketamine

Area of Science:

• Neuroscience
• Psychiatry
• Pharmacology

Background:

• Treatment-resistant depression (TRD) affects many patients, with limited predictors for ketamine response.
• Ketamine is an emerging treatment for TRD, but its efficacy varies significantly among individuals.

Purpose of the Study:

• To investigate the association between depression subtypes and patient response to ketamine treatment.
• To identify potential clinical predictors for antidepressant response to ketamine.

Main Methods:

• Ninety-seven participants with depression received six intravenous ketamine infusions.
• Depression, anxiety, and suicidal ideation were assessed using MADRS, HAMA, and SSI scales.
• Participants were classified into four mutually exclusive depression subtypes: melancholic, anxious, melancholic-anxious, and no subtype.

Main Results:

• Patients with melancholic or melancholic-anxious depression subtypes were less likely to respond or remit.
• These subtypes also required longer durations to achieve response or remission compared to anxious or no-subtype groups.
• Anxious and melancholic-anxious subtypes showed faster reductions in anxiety (HAMA) scores, while melancholic-anxious subtypes exhibited faster decreases in suicidal ideation (SSI) scores.

Conclusions:

• Ketamine shows promise as an antidepressant, particularly for non-melancholic or anxious depression subtypes.
• Depression subtype classification may serve as a predictor for ketamine response in treatment-resistant depression.
• Further research can refine personalized ketamine treatment strategies based on depression phenotypes.