title: Retrospective study of continuation electroconvulsive therapy in 50 patients.
abstract: OBJECTIVE
  To examine patient and treatment characteristics in continuation electroconvulsive therapy (c-ECT), defined as prolonged treatment with ECT with a maximum frequency of once a week to prevent relapse.
  
  
  METHODS
  Medical charts of 50 patients (mean age, 59 years; 74% were female) undergoing c-ECT were examined retrospectively for patient and treatment characteristics. Electrical stimulus dosage, seizure duration, and postictal suppression indices between the first and the last 4 ECT sessions were compared, and their associations with the time interval between c-ECT sessions were analyzed.
  
  
  RESULTS
  Almost all the patients (n=46; 92%) experienced recurrent medication-resistant mood disorders. During a median c-ECT period of 393 days (interquartile rate, 211-677 days), the frequency of c-ECT ranged from once a week (n=15; 30%) to once every 4 to 6 weeks (n=17; 34%), and ECT was administered almost exclusively bifrontotemporally (n=46, 92%). The mean (SD) time interval between consecutive c-ECT sessions was 19 (11) days. The number of days between c-ECT sessions correlated positively with median seizure duration (motor activity: r=0.390, P=0.005; electroencephalographic activity: r=0.351, P=0.013).
  
  
  CONCLUSIONS
  In 50 patients with long-standing, recurrent, medication-resistant mood disorders who were treated with c-ECT, increased time interval between consecutive c-ECT sessions was correlated with increased seizure duration. Whether bifrontotemporal c-ECT requires a lower frequency to sustain remission compared with unilateral c-ECT needs further investigation.
authors.affiliation: Department of Psychiatry, Rijnstate Hospital, Alysis Zorggroep, Arnhem, the Netherlands. jvanwaarde@alysis.nl
authors.forename: Jeroen A
authors.initials: JA
authors.lastname: van Waarde
authors.forename: Dianne
authors.initials: D
authors.lastname: Wielaard
authors.forename: Jaap
authors.initials: J
authors.lastname: Wijkstra
authors.forename: Bastiaan
authors.initials: B
authors.lastname: Verwey
authors.forename: Rose C
authors.initials: RC
authors.lastname: van der Mast
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003866:Depressive Disorder / Q000523:psychology / Q000628:therapy*; D004565:Electroconvulsive Therapy; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000150:complications / Q000628:therapy; D012189:Retrospective Studies; D012640:Seizures / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult