The authors have previously studied the short-term effect of the first acute electroconvulsive therapy (ECT) course (phase 1 study) on intractable
catatonic schizophrenia and the 1-year relapse rate after response to the acute ECT (phase 2 study) in middle-aged and elderly patients. Results indicated that, although acute ECT has an excellent short-term effect, the 1-year relapse rate after response to acute ECT is high despite the use of continuation
neuroleptics. In the present prospective study the effect was explored of continuation ECT with
neuroleptics on the prevention of relapse after response to a second acute ECT course in the relapsed participants of the phase 2 study. The present study included seven consecutive patients > 45 years of age with
catatonic schizophrenia (Diagnostic and Statistical Manual of Mental Disorders (4th edn; DSM-IV) who relapsed (despite the use of
neuroleptics) within 1 year after response to the first acute ECT course, and then responded to the second acute ECT course. The patients were given continuation ECT combined with
neuroleptics; four ECT sessions at weekly intervals, then four ECT sessions every 2 weeks, then three ECT sessions every 4 weeks. Clinical symptoms were evaluated by means of the Brief Psychiatric Rating Scale (BPRS) weekly for 48 weeks or until relapse. Relapse was defined as a BPRS score of at least 37 for 3 consecutive days. Three out of the seven patients (42.9%) had a sustained response to ECT during the 1-year follow-up period. In the seven patients the probability of relapse within 1 year under treatment with
neuroleptics alone (phase 2 study) was statistically higher than that under continuation ECT combined with
neuroleptics (present study). No statistical differences were seen between the phase 2 study and the present study in the severity of psychiatric symptoms, global social function, the number of acute ECT sessions or the dosage of
neuroleptics. No patient experienced a severe cognitive or physical adverse effect resulting from continuation ECT. Continuation ECT with
neuroleptics is an efficacious and safe treatment for maintaining a response in middle-aged and elderly patients with intractable
catatonic schizophrenia who have relapsed after a positive response to acute ECT despite the use of continuation
neuroleptics.