Switching treatment-resistant patients with schizophrenia or schizoaffective disorder to olanzapine: a one-year open-label study with five-year follow-up.
OBJECTIVE
To determine whether patients with treatment-resistant schizophrenia or schizoaffective disorder would respond when switched to olanzapine and whether they could maintain their response on this atypical antipsychotic.


METHODS
In this single-center, observational, 1-year open-label study, a cohort of patients was switched to olanzapine due to failure on previous treatment. The patients were followed up (retrospectively) for an additional 5 years. Patients had schizophrenia or schizoaffective disorder and all but one were treatment-resistant. The starting dose was 10 mg/day, with dosage adjustments based on physician judgment.


METHODS
The CGI-S and CGI-I scales were the primary outcome measures. During the observation period, positive and negative symptoms, hospital readmission rates and duration of hospitalization were measured, and treatment-emergent adverse events recorded.


RESULTS
Mean age of patients (n = 25) was 39.7 years; 19 were male, and all were Caucasian. The mean number of antipsychotics used prior to olanzapine was 4.6 with risperidone (76%) being the most common. The mean duration of olanzapine therapy was 8.6 months. The average number of hospital admissions per patient dropped from 1.32 during the year prior to olanzapine therapy to 0.39 after starting olanzapine. Total number of hospital days was 1042 the year before and 258 the year after olanzapine treatment. The mean CGI-S score improved from markedly ill at baseline to borderline/mildly ill at study end. The mean CGI-I score was rated much improved at study end. Few adverse events occurred during the study. Twelve patients remained on olanzapine monotherapy after 5 years of treatment (mean duration of 62 months).


CONCLUSIONS
Olanzapine may be a treatment option for patients who fail to respond to treatment with other antipsychotics. Importantly, this is one of the first reports showing that patients with schizophrenia can be maintained on atypical antipsychotic monotherapy for at least 5 years.
Karagianis
James L
JL
Memorial University of Newfoundland, St. John's, Newfoundland, Canada. jamiek@roadrunner.nf.net
LeDrew
Kellie K
KK
Walker
Daniel J
DJ
D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001569:Benzodiazepines; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D008297:Male; D000077152:Olanzapine; D010890:Pirenzepine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D011618:Psychotic Disorders / Q000188:drug therapy*; D012559:Schizophrenia / Q000188:drug therapy*; D012720:Severity of Illness Index; D016896:Treatment Outcome
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D010890:Pirenzepine; D000077152:Olanzapine