Effectiveness and safety of olanzapine in the treatment of schizophrenia among Asian patients switching from conventional antipsychotics

Does Switching Antipsychotics Ameliorate Weight Gain in Patients With Severe Mental Illness? A Systematic Review and Meta-analysis

OBJECTIVE

Obesity and adverse metabolic outcomes in patients with severe mental illness are clinically significant but potentially preventable. Importantly, the evidence for switching to antipsychotics to reduce cardiometabolic burden is unclear.

METHOD

PubMED, Embase, PsycINFO, and Cochrane were searched from inception to March 8, 2020. Articles reporting weight and metabolic changes after antipsychotic switching vs staying on the previous antipsychotic were meta-analyzed both across and within group.

RESULTS

Of 61 identified studies, 59 were meta-analyzed (40% rated high quality). In the switch-vs-stay pairwise meta-analyses, only aripiprazole significantly reduced weight (-5.52 kg, 95% CI -10.63, -0.42, P = .03), while olanzapine significantly increased weight (2.46 kg, 95% CI 0.34, 4.57, P = .02). Switching to aripiprazole also significantly improved fasting glucose (-3.99 mg/dl, 95% CI -7.34, -0.64, P = .02) and triglycerides (-31.03 mg/dl, 95% CI -48.73, -13.34, P = .0001). Dropout and psychosis ratings did not differ between switch and stay groups for aripiprazole and olanzapine. In before-to-after switch meta-analyses, aripiprazole (-1.96 kg, 95% CI -3.07, -0.85, P < .001) and ziprasidone (-2.22 kg, 95% CI -3.84, -0.60, P = .007) were associated with weight loss, whereas olanzapine (2.71 kg, 95% CI 1.87, 3.55, P < .001), and clozapine (2.80 kg, 95% CI 0.26, 5.34, P = .03) were associated with weight gain. No significant weight or other cardiometabolic changes were observed when switching to amisulpride, paliperidone/risperidone, quetiapine, or lurasidone.

CONCLUSIONS

Switching antipsychotics to agents with lower weight gain potential, notably to aripiprazole and ziprasidone, can improve weight profile and other cardiometabolic outcomes. When choosing switch agents, both the weight gain potential of the pre- and post-switch antipsychotic must be considered. Antipsychotic switching in psychiatrically stable patients must be weighed against the risk of psychiatric worsening.

Switching to paliperidone extended release in patients with schizophrenia dissatisfied with previous olanzapine treatment: Post hoc analysis of an open-label, prospective study

OBJECTIVE

This post hoc analysis of an open-label, single-arm, multicenter study was designed to assess the efficacy, safety, and tolerability of paliperidone extended release (ER) in Chinese patients with non-acute schizophrenia, after switching from olanzapine.

METHODS

Patients with schizophrenia who were dissatisfied with prior olanzapine treatment switched to flexible paliperidone ER (3-12 mg/day) based on clinical judgment. Change from baseline to week 12 in Positive and Negative Syndrome Scale (PANSS) total scores (primary endpoint), PANSS subscale scores, response rate, Clinical Global Impression-Severity (CGI-S) score, personal and social performance (PSP) scores, patient satisfaction with treatment score, change in sleep quality, level of daytime sleepiness and safety were evaluated.

RESULTS

Out of 118 enrolled patients, 95 (81%) completed the study. Mean duration of study was 76.9 (23.85) days. The primary endpoint, mean (SD) PANSS total score changed significantly from baseline to endpoint (-19.6 [18.71], P <.0001). Secondary endpoints including PANSS subscale score, PSP, patient satisfaction and daytime drowsiness also significantly improved (P <.001). Most commonly reported (≥1%) treatment-emergent adverse events were akathisia (n = 14 [12%]) and insomnia (n = 9 [8%]).

CONCLUSIONS

Switching to flexible-dosed paliperidone ER in patients dissatisfied with prior olanzapine treatment achieved good efficacy and tolerability consistently over 12 weeks.

Correlation between changes in quality of life and symptomatic improvement in Chinese patients switched from typical antipsychotics to olanzapine

PURPOSE

The aim of this study was to investigate the correlation between changes in symptoms and changes in self-reported quality of life among Chinese patients with schizophrenia who were switched from a typical antipsychotic to olanzapine during usual outpatient care.

PATIENTS AND METHODS

This post hoc analysis was conducted using data from the Chinese subgroup (n=475) of a multicountry, 12-month, prospective, noninterventional, observational study. The primary publication previously reported the efficacy, safety, and quality of life among patients who switched from a typical antipsychotic to olanzapine. Patients with schizophrenia were included if their symptoms were inadequately controlled with a typical antipsychotic and they were switched to olanzapine. Symptom severity was measured using the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impressions-Severity scale (CGI-S). Health-Related Quality of Life (HRQOL) was assessed using the World Health Organization Quality of Life-Abbreviated (WHOQOL-BREF). Paired t-tests were performed to assess changes from baseline to endpoint. Pearson's correlation coefficients (r) were used to assess the correlations between change in symptoms (BPRS and CGI-S scores) and change in HRQOL (WHOQOL-BREF scores).

RESULTS

Symptoms and HRQOL both improved significantly over the 12 months of treatment (P<0.001). Significant correlations were observed between changes from baseline to end of study on the BPRS and the CGI-S and each of the WHOQOL-BREF four domain scores and two overall quality-of-life questions. The correlation coefficients ranged from r=-0.45 to r=-0.53 for the BPRS and WHOQOL-BREF. The correlation coefficients were slightly smaller between the CGI-S and WHOQOL-BREF, ranging from r=-0.33 to r=-0.40.

CONCLUSION

For patients with schizophrenia, assessing quality of life has the potential to add valuable information to the clinical assessment that takes into account the patient's own perspective of well-being.

Olanzapine in Chinese patients with schizophrenia or bipolar disorder: a systematic literature review

BACKGROUND

Despite the burden of schizophrenia and bipolar disorder in the Chinese population, country-specific data to guide practitioners regarding antipsychotic therapy are lacking. The primary aim of this systematic review was to examine evidence of the efficacy, effectiveness, and safety of olanzapine in Chinese populations.

METHODS

A systematic literature search was conducted using databases covering international and Chinese core journals using search terms related to schizophrenia and bipolar disorder, specified countries (People's Republic of China, Hong Kong, Taiwan), and olanzapine treatment. Following initial screening, inclusion and exclusion criteria were applied to the search results to identify relevant studies from which data were extracted.

RESULTS

A total of 489 publications were retrieved and 61 studies were identified for inclusion. Most studies were related to schizophrenia (n=54), with six studies related to bipolar disorder and one study related to both conditions. The quality of study methods and reporting in international journals was noticeably better than in Chinese language journals. Most studies included relatively small patient populations and were of short duration. The efficacy of olanzapine in Chinese populations was confirmed by multiple comparative and noncomparative studies that found statistically significant reductions in symptom measures in studies conducted for ≥6 weeks (schizophrenia) or ≥3 weeks (bipolar disorder). Findings related to effectiveness (treatment discontinuation, quality of life, and neurocognitive improvements) were generally consistent with those observed in non-Chinese populations. No new safety signals specific for Chinese populations were raised for olanzapine.

CONCLUSION

Chinese and non-Chinese populations with schizophrenia or bipolar disorder treated with olanzapine display broadly similar responses. Differences between these populations, especially in relation to the relative efficacy of olanzapine versus other antipsychotics, may warrant further investigation via studies incorporating both populations. Use of local data to provide evidence for practice guidelines should be encouraged, and may promote ongoing improvements in the quality of research and study reporting.

Withdrawal symptoms and rebound syndromes associated with switching and discontinuing atypical antipsychotics: theoretical background and practical recommendations

With the widespread use of atypical or second-generation antipsychotics, switching treatment has become current practice and more complicated, as the pharmacological profiles of these agents differ substantially despite their similarity in being 'atypical'. All share the ability to block dopamine D₂ receptors, and most of them also block serotonin 5-HT2A receptors. Apart from these common features, some atypical antipsychotics are also able to block or stimulate other dopamine or serotonin receptors, as well as histaminergic, muscarinergic or adrenergic receptors. As a result of the varying receptor affinities, in switching or discontinuing compounds several possible pitfalls have to be considered, including the occurrence of withdrawal and rebound syndromes. This article reviews the pharmacological background of functional blockade or stimulation of receptors of interest in regard to atypical antipsychotics and the implicated potential withdrawal and rebound phenomena. A MEDLINE search was carried out to identify information on withdrawal or rebound syndromes occurring after discontinuation of atypical antipsychotics. Using the resulting literature, we first discuss the theoretical background to the functional consequences of atypical antipsychotic-induced blockade or stimulation of neurotransmitter receptors and, secondly, we highlight the clinical consequences of this. We then review the available clinical literature on switching between atypical antipsychotics, with respect to the occurrence of withdrawal or rebound symptoms. Finally, we offer practical recommendations based on the reviewed findings. The systematic evaluation of withdrawal or rebound phenomena using randomized controlled trials is still understudied. Knowledge of pharmacological receptor-binding profiles may help clinicians in choosing adequate switching or discontinuation strategies for each agent. Results from large switching trials indicate that switching atypical antipsychotics can be performed in a safe manner. Treatment-emergent adverse events during or after switching are not always considered to be, at least in part, associated with the pre-switch antipsychotic. Further studies are needed to substantiate the evidence gained so far on different switching strategies. The use of concomitant medication, e.g., benzodiazepines or anticholinergic drugs, may help to minimize symptoms arising from the discontinuation or switching of antipsychotic treatment.

One-year outcomes in schizophrenia after switching from typical antipsychotics to olanzapine in Japan: an observational study

Background

The purpose of this study was to assess the 1-year clinical, functional, and safety-related outcomes following a switch to olanzapine of at least one typical antipsychotic drug in the previous regimen in the treatment of patients of schizophrenia in Japan.

Methods

Using data from a large 1-year prospective, multicenter, naturalistic study of olanzapine for the treatment of schizophrenia in Japan, patients who were switched from any oral typical antipsychotic to olanzapine were identified. Mixed models for repeated measures, controlling for baseline demographics, were utilized to assess outcomes for clinical and functional measures.

Results

Of the 262 patients who switched from typical antipsychotics to olanzapine, 41% were outpatients and 59% were inpatients. Most of these patients were switched due to poor medication efficacy (71.0%) or medication intolerability (25.6%). Most patients (71.4%) completed the 1-year study. Clinically and statistically significant (P < 0.01) improvements were observed in patient illness severity and health-related quality of life, including improvements in global symptom severity and in positive, negative, depressive, and cognitive symptoms. Over half of the patients (58.3%) demonstrated a treatment response to olanzapine and 47.4% achieved symptom remission. Mean weight gain from baseline to endpoint was 2.31 ± 4.72 kg, with 30.4% of patients experiencing clinically significant weight gain (at least 7% of baseline weight).

Conclusion

During this 1-year naturalistic treatment of schizophrenia patients in Japan, switching from typical antipsychotics to olanzapine resulted in significant improvements in patients’ clinical and functional outcomes. Approximately one-third of patients had clinically significant weight gain. These findings highlight the favorable benefit to risk profile of switching to olanzapine following failure on typical antipsychotics.

Psychotropic prescription practices in east Asia: looking back and peering ahead

PURPOSE OF REVIEW

The present review focuses on the pharmacoepidemiological issues of psychotropic drug use in countries within east Asia, with special emphasis on antipsychotic, antidepressant and benzodiazepine prescriptions. Pharmacogenetic studies in different ethnic groups are also reviewed.

RECENT FINDINGS

Recent studies have revealed the prevalence of antipsychotic polytherapy (defined as the use of more than one antipsychotic; up to 45.7%), less conservative antipsychotic use (defined as the use of more than 1000 mg/day chlorpromazine equivalents; up to 17.9%) and depot antipsychotic use (up to 15.3%) in different populations in east Asia. Clozapine is commonly prescribed (up to 60%) in China. There is a trend of increasing second-generation antipsychotic use in east Asian countries. Up to 67.5% of patients received newer antidepressants such as selective serotonin reuptake inhibitors. Benzodiazepine medications are used in up to 29.9% of study populations. Socioeconomic factors appear to be one of the major common factors that affect the prescription of antipsychotics and newer antidepressants. Pharmacogenetic factors associated with antipsychotic response, weight gain and extrapyramidal side effects have been examined. Treatment adherence and pharmacoeconomic factors are relatively understudied.

SUMMARY

Future studies on prescribing trends of antipsychotics and antidepressants need to focus on children, adolescent and elderly patient populations, the impact of changing prescription trends and the long-term effects on patients and their caregivers, as well as pharmacogenetic factors, which can potentially pave the way for better and more individualized prescription of psychotropic drugs in east Asia.

Recent progress in the research field of neuropharmacology in China

In recent years, Chinese neuropharmacologists have done a lot of basic and practical work in neuropharmacology, especially in the fields of pain, drug dependence, depression, Alzheimer's disease, schizophrenia, having obtained some exciting results that are of great significance for the development of neuropharmacology. Here I would like to review recent progress in the research fields of neuropharmacology in China.