Background: Electroconvulsive therapy (ECT) remains an effective intervention for severe and treatment-resistant psychiatric disorders. While acute response to ECT is well established, clinical predictors of long-term outcomes remain insufficiently characterized. This study examines the impact of illness duration on long-term ECT effectiveness, operationalized specifically as the amount of time elapsed from treatment completion to psychiatric rehospitalization. By controlling for primary diagnosis, psychiatric comorbidities, sleep disorders, and number of ECT sessions, this study aims to clarify the role of illness chronicity in sustaining remission and reducing relapse risk, while recognizing rehospitalization as a primary indicator of long-term clinical stability. Methods: We conducted a retrospective cohort study of 249 patients treated with ECT at a tertiary psychiatric hospital. Time to first psychiatric rehospitalization following completion of ECT was used as a proxy for relapse. Illness duration was analyzed alongside primary diagnosis, psychiatric comorbidities, sleep disorders, and number of ECT sessions to assess its independent association with long-term outcomes. Results: Nearly half of patients (44.6%) demonstrated sustained clinical benefit, defined by delayed or absent rehospitalization during a three-year follow-up period. Shorter illness duration emerged as a key predictor of more durable remission. Patients with illness duration below 15 years, and particularly those with less than 5 years of illness, experienced significantly longer periods without rehospitalization compared with individuals with longer disease trajectories, despite the latter often receiving more ECT sessions. Conclusions: Shorter illness duration is associated with improved long-term outcomes following ECT, suggesting that earlier intervention may enhance treatment durability. These findings support reconsidering ECT earlier in the course of treatment-resistant psychiatric disorders. Prospective studies integrating clinical, cognitive, and biological markers are warranted to improve patient selection and develop personalized ECT strategies.
Iliuță et al. (Mon,) studied this question.