Correlation Between Cognitive Function and Relapse of Schizophrenia Regarding Dose Reduction

Correlation Between Cognitive Function and Relapse of Schizophrenia Regarding Dose Reduction in Patients Undergoing High-dose Antipsychotic Therapy

To reduce antipsychotics to under 1000mg in patients with schizophrenia taking more than 1000mg/day and to evaluate relationship between relapse and cognitive function.

We attempted to reduce the dose of antipsychotics to ≤1000-mg chlorpromazine eq./day. The dose was gradually reduced at a rate of ≤50-mg chlorpromazine eq./week, and the reduction was discontinued if the subjects relapsed. The differences in baseline cognitive function were analyzed between the patients with no relapse and relapse groups.

Inclusion Criteria:

• inpatients with a diagnosis of schizophrenia, and
• those in the chronic phase receiving mean daily antipsychotic doses exceeding 1000-mg chlorpromazine eq./day.

Exclusion Criteria:

• mental retardation,
• substance abuse or dependence,
• a history of major head trauma,
• serious medical or neurological disorders, or
• depot antipsychotic injections within the previous 3 months and electroconvulsive therapy within the previous 6 months