Extent of attaining and maintaining symptom remission by antipsychotic medication in the treatment of chronic schizophrenia: evidence from the CATIE study.

BACKGROUND

Data on attaining and maintaining symptom remission associated with specific antipsychotic medications are rare and variant.

AIMS

To examine remission rates and their variation by antipsychotic medication in chronic schizophrenia in the National Institute of Mental Health Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) given it has an 18-month duration and representative antipsychotic medications.

METHODS

Symptom remission was examined using the Remission in Schizophrenia Working Group remission criteria of attaining and maintaining for 6 months with mild ratings on 8 specific Positive and Negative Syndrome Scale (PANSS) items. Remission rates were assessed (a) up to 18 months across CATIE's switching phases (n = 1332); and (b) in phase 1 (that involved double-blind randomization to one of five antipsychotic medications) to compare antipsychotic medication differences in attaining and maintaining remission among patients not in remission at baseline (n = 941).

RESULTS

At baseline 16.2% of patients were in symptomatic remission. Across the medication phases of CATIE only 11.7% attained and then maintained at least 6 months of symptomatic remission, and 55.5% (n = 623) experienced no symptom remission at any visit. During the first medication randomization phase, attaining and maintaining remission for 6 months was highest for the olanzapine (12.4%) medication group followed by the quetiapine (8.2%), perphenazine (6.8%), ziprasidone (6.5%), and risperidone (6.3%) groups.

CONCLUSIONS

As currently defined, remission appears to be a very difficult therapeutic target to attain and maintain in chronic schizophrenia and may differ by antipsychotic medication. Pragmatically, remission gradients may be effectively studied by applying modified duration and symptom criteria.