Will Electroconvulsive Therapy (ECT) be effective after 16 failed attempts?

ECT Effectiveness After 16 Failed Attempts

After 16 failed ECT treatments, continuing with additional ECT sessions is unlikely to be effective and alternative treatment approaches should be considered.

Understanding Treatment Resistance and ECT Outcomes

Treatment-resistant depression (TRD) is typically defined after failure of at least two adequate trials of antidepressant medications 1. When it comes to ECT specifically, there is no clear consensus on how many failed ECT sessions constitute treatment failure, but 16 unsuccessful attempts significantly exceeds typical course lengths.

The effectiveness of ECT diminishes with increasing levels of treatment resistance. Research indicates that:

• Higher treatment resistance scores are associated with significantly smaller reductions in depression symptoms and lower chances of response 2
• Patients with lower treatment resistance undergo fewer ECT sessions (average 13 ± 6) compared to those with higher resistance (16 ± 7) 2
• In medication-resistant patients, bilateral ECT response rates drop to approximately 50% from the expected 80-90% 3

Why 16 Failed Sessions Indicates Poor Prognosis

A standard course of ECT typically consists of 6-12 treatments. When considering continuation:

• Guidelines indicate that ECT is "effective only in resolving an acute illness and will not prevent relapse" 1
• There are no established parameters for what constitutes an optimal "course" of ECT, but 16 sessions far exceeds typical recommendations 1
• The Massachusetts General Hospital Staging model (MGH-s) assigns three points for a single ECT failure, indicating the significance of even one failed course 1

Alternative Approaches to Consider

When ECT has failed after multiple attempts, consider:

1. Reassess diagnosis and comorbidities:

   • Evaluate for comorbid personality disorders or other mental conditions that may be complicating treatment 1
   • Consider substance use disorders that might interfere with treatment response 1

2. Alternative neurostimulation approaches:

   • Deep brain stimulation (DBS)
   • Vagus nerve stimulation (VNS)
   • Transcranial magnetic stimulation (TMS) 1

3. Pharmacological strategies:

   • Trial of medications with different mechanisms of action than previously tried 1
   • Consider augmentation strategies with mood stabilizers or atypical antipsychotics 1

Important Considerations and Caveats

• The evidence base for ECT efficacy has been questioned, with some researchers noting methodological flaws in placebo-controlled studies and concerns about persistent memory loss in 12-55% of patients 4
• Continuing ECT after 16 failed attempts may expose the patient to additional cognitive side effects without significant likelihood of benefit
• If ECT is continued despite previous failures, careful monitoring for adverse effects is essential, particularly for prolonged seizures and cognitive impairment 1

While maintenance ECT can be effective for patients who initially respond to treatment 5, 6, there is no evidence supporting continued ECT in patients who have not shown response after 16 sessions. The focus should shift to alternative treatment modalities to improve quality of life and reduce morbidity and mortality associated with persistent severe depression.