To investigate the prevalence, characteristics, and prognosis of depressive patients who show early complete remission after right unilateral (ultra)brief pulse electroconvulsive therapy (ECT).
Early complete remitters (ECRs) were those patients who were rated 1 on the Clinical Global Impression Scale (maximum score, 7) within 4 ECT sessions and achieved remission (Montgomery Åsberg Depression Rating Scale score, <10). The ECRs were compared with late complete remitters (LCRs), which fulfilled the same criteria after 9 to 12 ECT sessions and with the nonremitters/nonresponders (NRs).
Of the 87 patients who completed the index treatment phase, 50 (57.5%) achieved remission. Of these remitters, 12 (14%) were ECRs and 9 (10%) were LCRs. The ECRs were characterized by a higher mean age (71.0 vs 53.9 years; P = 0.008), a shorter current depressive episode (mean, 5.8 vs 15.4 months; P = 0.042), and more psychotic features (75% vs 22%; P = 0.030) and were treated more often with brief pulse ECT (P = 0.030) compared with the LCRs. Although not significant, cognitive performances of ECRs were lower than that of LCRs at baseline with a large effect size: Autobiographical Memory Interview (P = 0.099; d = 0.83), Amsterdam Media Questionnaire (P = 0.114; d = 0.84), and Letter fluency (P = 0.071; d = 0.95). The ECR group had a lower relapse rate during 6 months’ follow-up: 10% (1 of 10) versus 62.5% (5 of 8) (P = 0.043). No significant differences in demographic and clinical characteristics were found between LCRs (n = 9) and NRs (n = 27).
Older patients with a psychotic depression and a profile of cognitive slowing have a high chance of achieving complete remission within 4 ECT sessions, with a favorable 6-month prognosis.