Electroconvulsive therapy (ECT) is a safe and effective procedure in unipolar depression in older adults; however, less is known about clinical features and trajectories among patients who do not respond. In this retrospective, naturalistic study, we examine characteristics associated with ECT response among older adults with unipolar depression who received ECT over an 8-year period and describe long-term outcomes for nonresponders.
We retrospectively identified patients 65 years or older with major depressive disorder who were treated with ECT during an 8-year period. We reviewed demographic and clinical factors among patients who responded to ECT and those who did not. Clinic notes were reviewed for ECT nonresponders to determine Clinical Global Impressions scores in the 24 months after ECT treatment.
We identified 140 patients meeting the inclusion criteria. Most patients (65%) responded to ECT. Fewer previous antidepressant trials, lower baseline Montreal Cognitive Assessment scores, and lower baseline Montgomery-Asberg Depression Rating Scale scores were associated with an increased likelihood of ECT response. Among the 49 (35%) nonresponders, another 12 (24.5%) responded to a variety of treatments within 2 years after ECT. There were no serious adverse effects of treatment.
Most patients responded to ECT, many of whom had severe illness that had been refractory to numerous medication trials. Among nonresponders, a subset improved over time through a variety of treatments. However, most patients who did not respond to ECT had persistent depression after 2 years.