Electroconvulsive Therapy and the Longitudinal Modulation of Sleep Architecture

Area of Science:

• Neuroscience
• Sleep Medicine
• Psychiatry

Background:

• Sleep disturbances, particularly reduced slow-wave activity (SWA) during non-rapid eye movement (NREM) sleep, are linked to major depressive disorder.
• The precise mechanisms connecting sleep and mood regulation in depression require further elucidation.

Purpose of the Study:

• To investigate sleep architecture changes in patients with depression undergoing electroconvulsive therapy (ECT).
• To explore the relationship between electroencephalographic (EEG) slow-wave activity (SWA) and depressive symptom improvement following ECT.

Main Methods:

• Sleep EEG data were collected using wireless Dreem devices throughout the ECT course.
• Sleep stages (REM, NREM stages N1-N3) were manually scored, and SWA was quantified.
• Depression severity was assessed using the Quick Inventory of Depressive Symptomatology-Self Report (QIDS).

Main Results:

• N3 sleep percentage increased in responders, and SWA increased across all participants during ECT.
• SWA showed a significant negative correlation with QIDS scores, indicating reduced depression severity with increased SWA.
• Mediation analysis confirmed that SWA changes mediated the antidepressant effects of ECT in responders.

Conclusions:

• ECT enhances N3 sleep and SWA in patients who respond to treatment.
• Increased SWA is a significant mediator of depressive symptom improvement following ECT.
• SWA serves as a potential biomarker for antidepressant response and a target for adjunctive sleep-based therapies.