Long-Acting Typical and Atypical Antipsychotics in Treatment of Schizophrenia: A Retrospective Comparison

Objective: Long-acting antipsychotics were introduced to improve therapeutic outcomes in patients with schizophrenia experiencing sub-optimal improvement due to lack of or partial adherence to long-term treatment. Approximately 15% of schizophrenia patients in maintenance antipsychotic treatment receive depot preparations. Many studies investigated characteristics of long-acting typical and atypical antipsychotics. However, so far there has been a dearth of prospective and retrospective comparison studies of typical and atypical depots. Therefore we retrospectively compared typical and atypical long-acting injectable antipsychotics regarding socio-demographic, clinical, and treatment characteristics of patients with schizophrenia in the present study. Method: This study was conducted at the Psychotic Disorders Unit of Gaziantep University, School of Medicine, Department of Psychiatry. We reviewed the charts of all 220 outpatients diagnosed with schizophrenia (n=207) or schizoaffective disorder (n=13) according to DSM-IV. Sixty-eight patients from this population, had used or were still using long-acting antipsychotics. Forty-six of 68 patients had used or were using typical depots (TD) (flupenthixol decanoate; 28, zuclopenthixol decanoate; 15, fluphenazine decanoate; 3) and 22 of them had used or were still using long-acting risperidone (LAR). The medical charts for these two groups were reviewed and the findings were compared. Results: The reason for initiating long acting antipsychotics was non-adherence to oral antipsychotics in almost all patients. The average duration of staying on treatment was 20.43 +/- 29.85 and 15.19 +/- 8.12 months for To and LAR groups, respectively (t=2.25, df=66, p=0.02). 58.7% of TD and 90.9% of LAR patients were still using these drugs (chi 2=5.206, df=1, P=0.02). Concomitant use of other psychotropic drugs was very common. The most co-prescribed drugs were oral antipsychotics especially atypicals in both groups. Significant decreases were found in both TD and LAR groups with respect to PANNS and CGI-symptom severity scores, except in PANNS negative subscale score in TD group, in which decrease wasn't statistically significant. Nevertheless no statistically significant difference was detected when CGI-S and PANNS scores including PANNS negative subscale scores of TD and LAR groups were compared. The LAR patients had fewer adverse effects than TD patients as a group. Discussion: Poor therapeutic outcome because of non-adherence to oral antipsychotics could be improved with use of long-acting antipsychotics; in schizophrenia. In our study there was no significant difference between TD and LAR treatments in symptom improvement based on PANNS and CGI. TDs were superior to LAR regarding duration of treatment, but LAR was superior in terms of duration of staying in the same treatment and causing fewer adverse effects.