Olanzapine has better efficacy compared to risperidone for treatment of negative symptoms in schizophrenia

Abstract

Objective:The safety and efficacy profile of risperidone and olanzapine were compared in a double-blind trial that used doses widely accepted in clinical practice.Methods:Subjects (n = 71) who met Diagnostic and Statistical Manual of Mental Disorders-IV criteria for schizophrenia were randomly assigned to receive 2–8 mg/day of risperidone (mean modal dose = 5.5 mg/day) or 5–20 mg/day of olanzapine (mean modal dose = 14.4 mg/day) for 1 year.Results:The two study groups were similar at baseline in all aspects. Seventy-four percent of the participants completed the trial, with no between-differences in the proportion of dropouts. Olanzapine group showed significantly greater improvement in negative symptoms in assessments at 3rd, 6th, 9th, and 12th months (P = 0.05, 0.00, 0.00, and 0.00, respectively). Clinical global impression of severity (CGI-S) scores were consistently lower in the olanzapine group at 3rd, 6th, and 9th months (P = 0.01, 0.03, and 0.05, respectively) as measured by positive and negative symptom scale (PANSS). Total scores on PANSS, positive symptoms, general psychopathology, and CGI improvement showed comparable improvement at 3rd, 6th, 9th, and 12th months of follow-up (all subjects, including dropouts). Severity of extrapyramidal symptoms was low in both groups, with no between-group differences. Mean change in body weight, fasting blood sugar, and fasting cholesterol was comparable in both groups. Risperidone group had significant hyperprolactinemia after one year (P = 0.03).Conclusions:Both treatments were well-tolerated and efficacious. Greater reductions in severity of the illness and negative symptoms were seen with olanzapine consistently through 1 year. The frequency and severity of extrapyramidal symptoms were negligible and similar in the two treatment groups. Weight gain, hyperlipidemia, and hyperglycemia were comparable in both groups. Risperidone produced significant hyperprolactinemia.

The Comparison of Olanzapine and Risperidone Treatment in Male Schizophrenic Patients using Positive and Negative Syndromes Scale (PANSS)

“…This difference was because Shah et al (2011) used participants with the outpatient method, so the physical activity and the dose of drugs could not be fully controlled while the study by Conley et al (2001) used participants who were hospitalised. Nevertheless, Tran et al (1997) [ 9 ] and Kumar et al (2016) [ 10 ] who recruited participants who were hospitalised also found similar results to the results of Shah et al (2011) [ 8 ].…”

“…On the other hand, the positive scale and the total score between the two groups were found to be comparable [ 8 ]. Similarly, Shah et al (2011) and Kumar et al (2016) reported that although the improvement in the negative scale was significantly higher in the group treated with olanzapine, there were no significant differences for the positive scale and the total score of PANSS in both groups [ 9 ] [ 10 ].…”

Examining the effects of the histone methyltransferase inhibitor BIX-01294 on histone modifications and gene expression in both a clinical population and mouse models

“…Abnormalities in the cholinergic system are seen in schizophrenia, with the majority of findings indicating decrements in cholinergic neurotransmission [56,57]. The antipsychotic medications olanzapine and clozapine modulate cholinergic neurotransmission, and have both the greatest efficacy in treatment-resistant schizophrenia, and reductions in severity of negative symptoms [58]. Additionally, nicotine alters cholinergic signaling, increases global BDNF levels, and is highly used in persons with schizophrenia [59,60].…”

Olanzapine has poorer efficacy than risperidone for the treatment of the negative symptoms of schizophrenia

“…Suresh Kumar et al . [ 1 ] randomized patients with schizophrenia ( n = 71) to receive either olanzapine (mean modal dose, 14.4 mg/day) or risperidone (mean modal dose, 5.5 mg/day) for 1 year. They reported that olanzapine was associated with significantly greater improvements in negative symptom ratings at all follow-up visits, that is, at months 3, 6, 9, and 12.…”

“…In research, primary and secondary outcomes should be stated a priori, and greater emphasis should be laid on the former than on the latter. [ 2 ] There was no indication whatsoever that the authors[ 1 ] intended to study negative symptoms as their primary outcome.…”