Delayed onset and prolonged interictal delirium following electroconvulsive therapy

Area of Science:

• Geriatric Psychiatry
• Neuroscience
• Clinical Psychology

Background:

• Electroconvulsive therapy (ECT) is a well-established, safe, and effective treatment for severe depression, particularly in older adults.
• Cognitive side effects like transient confusion and memory impairment are known but generally reversible.
• Interictal delirium, occurring between ECT sessions, is an uncommon adverse event, especially in patients without predisposing risk factors.

Observation:

• A case study involving a male patient diagnosed with depression, who had no known risk factors for delirium.
• The patient developed interictal delirium approximately two days following his sixth electroconvulsive therapy session.
• The delirium presented as a significant cognitive disturbance occurring outside the immediate post-treatment period.

Findings:

• The patient's interictal delirium, despite the absence of typical risk factors, emerged after multiple ECT sessions.
• The delirium symptoms were successfully managed with appropriate medical intervention.
• Full recovery from the interictal delirium was observed within one week of treatment initiation.

Implications:

• This case highlights that interictal delirium, though rare, can occur in electroconvulsive therapy patients even without identifiable risk factors.
• It underscores the importance of vigilant monitoring for cognitive side effects beyond the immediate post-ECT period.
• Early recognition and treatment of interictal delirium are crucial for patient recovery and management in geriatric depression treatment.