Efficacy of amisulpride and olanzapine for negative symptoms and cognitive impairments: An open-label clinical study

Abstract

Background: Negative symptoms and diminished cognitive ability are also considered as core features of schizophrenia. There are many studies in which negative symptoms and cognitive impairments are individually treated with atypical antipsychotic in comparison with either a placebo or a typical antipsychotic. There is paucity of studies comparing the efficacy of olanzapine and amisulpride on improvement of negative symptoms and cognitive impairments.

Aim: To examine the effectiveness of amisulpride and olanzapine in treatment of negative symptoms and cognitive impairments in schizophrenia.

Materials and methods: Total 40 adult inpatients diagnosed as schizophrenia fulfilling inclusion/exclusion criteria were included in the study with their informed consent. These patients were recruited consecutively to one of the two drug regimen group, i.e. tab Amisulpride (100-300 mg/day) and tab Olanzapine (10-20 mg). Patients were evaluated on day 0 and day 60 with various rating scales like Scale for the Assessment of Negative Symptoms (SANS), Scale for the Assessment of Positive Symptoms (SAPS), Schizophrenia Cognition Rating Scale (SCoRS), Brief Psychiatric Rating Scale (BPRS), Calgary Depression Scale for Schizophrenia (CDSS), and three different scales to measure drug side effects.

Results: The mean SANS score in amisulpride and olanzapine group at day 0 and day 60 were 83.89 (±12.67) and 21.00 (±11.82) and 84.40 (±13.22) and 26.75 (±12.41), respectively. The mean rank of SCoRS global in amisulpride and olanzapine group at day 0 and day 60 were 4.78 (±1.13) and 2.78 (±0.63) and 4.85 (±1.18) and 3.30 (±1.12), respectively. The percentage improvement in SANS, SAPS, SCoRS interviewer, and SCoRS global in amisulpride group are 74.96%, 13.36%, 54.14%, and 42.00%, respectively. Similarly in olanzapine group percentage improvement in SANS, SAPS, SCoRS interviewer, and SCoRS global are 68.30%, 30.28%, 35.22%, and 31.95%, respectively. There is significant improvement in SANS, SCoRS, SAS, BPRS, and PANSS (Insight) in both amisulpride and olanzapine groups at the two time points. However, there is no significant difference between amisulpride and olanzapine group of patients.

Conclusion: Both amisulpride and olanzapine group patients showed significant improvement in negative and cognitive symptoms from baseline to endpoint, but there was no significant difference between amisulpride and olanzapine group of patients.

Keywords: Negative symptoms; amisulpride; cognitive impairment; olanzapine; schizophrenia.