Schizophrenia is a chronic, severe, and disabling mental disorder. An evaluation of clinical predictors to clozapine was described.

Identify clinical predicting factors to clozapine.

This is a cross-sectional study including patients diagnosed with schizophrenia or schizoaffective disorder according to the DSM 5 criteria and treated with clozapine.

Of the 33 patients, 78.8% were males and 69.7% of them were single. The mean age was 36 years old. The mean age at the onset of the disorder was 24 years old. The mean number of hospitalizations was 6. The beginning of the mental disorder was acute in 21.2% of the cases. The mean duration of the disease course before starting clozapine treatment was 11 years. The mean duration of treatment was 19 months. The diagnosis according to DSM 5 criteria was schizophrenia in 87.9 and schizoaffective disorder in 12.1% of cases. The outcome was assessed by PANSS and BPRS scales with a symptomatic remission in 63.63% of cases. The analytical study revealed a significant correlation between favorable evolution and the latest onset of the disorder (P = 0.04), the number of previous hospitalizations (P = 0.009), disorder's duration (P = 0.032), male sex (P = 0.0004) and secondary resistance (P < 10−3).

The evaluation of clinical factors is important in our practice in order to improve the response to clozapine. Otherwise, adherence to treatment and quality of insight are determining factors of the treatment response.

The authors have not supplied their declaration of competing interest.