Antipsychotic treatment and risk of discontinuation and hospitalization in first-episode schizophrenia: a nationwide population-based study

Real-World Effectiveness, Economic, and Humanistic Outcomes of Selected Oral Antipsychotics in Patients with Schizophrenia: A Systematic Review Evaluating Global Evidence

Background

Schizophrenia is a complex, chronic mental health disorder that confers a substantial disease burden globally. Oral antipsychotic treatments (OATs) are the mainstay for treating early and advanced stages of schizophrenia. Our systematic review aimed to synthesize literature describing real-world effectiveness, economic, and humanistic outcomes of OATs (asenapine, brexpiprazole, cariprazine, iloperidone, lumateperone, lurasidone, olanzapine/samidorphan, paliperidone, and quetiapine) for successful management of the disease.

Methods

PubMed, American Psychological Association PsycINFO (EBSCOhost), and Cumulative Index of Nursing and Allied Health Literature were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting real-world effectiveness, costs, humanistic, behavioral (eg, interpersonal relations, suicide ideation), medication adherence, and product-switching outcomes for selected OATs published in English from January 2010 to March 2022 were identified and evaluated qualitatively.

Results

We included 48 studies with different designs providing extensive evidence on schizophrenia. All studies were conducted in countries outside of the United States. In most studies, antipsychotic medications were more effective than placebo, suggesting their value in the management of schizophrenia. Sixteen studies measured the economic outcomes of OATs. Eight studies assessed humanistic outcomes, while one reported behavioral outcomes in three second-generation antipsychotics. Medication adherence was described in two studies, while five studies evaluated product switching. Non-adherence was commonly reported for OATs. Medication non-adherence and treatment discontinuation were predominant factors contributing to the economic burden of schizophrenia.

Conclusion

Our research showcased a significant knowledge gap across OATs spanning the humanistic and behavioral outcomes and medication adherence and switching, suggesting a need for robust evidence generation to help clinicians and payers make informed decisions regarding treatment opportunities and cost-effective strategies for patients with schizophrenia.

Comparative effectiveness of antipsychotic monotherapy and polypharmacy in schizophrenia patients with clozapine treatment: A nationwide, health insurance data-based study

Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia (TRS). However, it remains uncertain whether antipsychotic augmentation to clozapine has the superior effectiveness over clozapine alone and the effect size of clozapine compared to other antipsychotic drugs in TRS. Therefore, we examined the comparative effectiveness of antipsychotic monotherapy and polypharmacy on the risk of psychiatric admission and treatment discontinuation in TRS. Data were collected from the Health Insurance Review Agency database between January 2010 and December 2019 in South Korea. Among prevalent patients with schizophrenia, we defined 22,327 patients with TRS as those who had been prescribed with clozapine at least once during the entire observation period. Stratified Cox proportional hazards regressions were performed using data on all antipsychotic prescriptions of patients with TRS to investigate the risk of psychiatric hospitalization and treatment discontinuation associated with antipsychotic treatment. In individual comparisons, clozapine monotherapy was the most effective for the risk of psychiatric hospitalization compared to no use (hazard ratio [HR] = 0.23, 95% confidence interval [CI] = 0.22-0.25). In group comparisons, clozapine with long-acting injectable (LAI) second-generation antipsychotics (SGA) was superior to clozapine monotherapy for the risk of psychiatric hospitalization (HR = 0.60, 95%CI = 0.41-0.88). Clozapine monotherapy was associated with the lowest risk of treatment discontinuation in the individual and group comparisons. This retrospective observational population-based study reports that clozapine with LAI SGA is more effective in lowering the risk of psychiatric hospitalization in antipsychotic group comparison with the reference of clozapine monotherapy.

Comparative Effectiveness of Antipsychotics in Preventing Readmission for First-Admission Schizophrenia Patients in National Cohorts From 2001 to 2017 in Taiwan

BACKGROUND AND HYPOTHESIS

Antipsychotics remain the main treatment for schizophrenia, but their effectiveness is challenging to compare. We aimed to assess the comparative real-world effectiveness of antipsychotics in preventing readmission among patients in Asia with early-stage schizophrenia to inform clinical decision making.

STUDY DESIGN

We did a retrospective cohort study of first-admission schizophrenia patients (ICD-9-CM: 295; ICD-10-CM: F20 and F25) from January 1, 2001, to December 31, 2017. The cohort was identified from the National Health Insurance Research Database NHIRD for Psychiatric Inpatients. The exposure was any antipsychotics prescribed post-discharge. The primary outcome was the readmission risk due to psychotic disorders, which was measured by adjusted hazard ratios (aHRs). Within-individual extended Cox models were applied for analyses, where the periods of oral risperidone use served as his or her own control.

STUDY RESULTS

We selected 75 986 patients (men, 53.4%; mean [SD] age, 37.6 [12.0] years; mean [SD] duration of follow-up, 8.9 [5.0]) who were first admitted to psychiatric wards with schizophrenia in Taiwan. Among them, 47 150 patients (62.05%) had at least one readmission within 4 years. Compared to the period under treatment with oral risperidone, that under monotherapy with long-acting injectable antipsychotics (LAIs) had the lowest risk for psychotic readmission, with a risk reduction of 15-20%. However, the prevalence of person-prescription prevalence of LAIs remained low (< 10%) during the follow-up period.

CONCLUSIONS

The use of LAIs after the first admission for schizophrenia has notable advantages in preventing readmission. Such formulations should be offered earlier in the course of illness.

Comparative effectiveness and safety of antipsychotic drugs in patients with schizophrenia initiating or reinitiating treatment: A Real-World Observational Study

OBJECTIVE

To compare the effectiveness and safety of various second-generation antipsychotics (SGAs), newer oral and long-acting injectable (LAI) SGAs, and first-generation antipsychotics (FGAs) treatments in patients with schizophrenia or schizoaffective disorder (SCZ).

METHODS

This retrospective cohort study included medical administrative information for patients with a diagnosis of SCZ living in Quebec (Canada), initiating or reinitiating at least one antipsychotic (AP) drug (with a clearance baseline period of 12 months without any APs). Effectiveness was defined by a reduced risk of hospitalization for mental disorder and discontinuation, and safety by a reduced risk of all-cause death and hospitalization for non-mental disorder, 2 years after AP initiation or reinitiation. Cox proportional hazard models were used to estimate the events associated with different antipsychotics compared with oral olanzapine.

RESULTS

The study cohort included 19,615 patients initiating or reinitiating an antipsychotic drug between January 2006 and December 2015. Results showed better effectiveness of clozapine (adjusted HR 0.36, 95% CI 0.30-0.42, p < 0.0001) and LAI SGAs (adjusted HR 0.56, 95% CI 0.51-0.61, p < 0.0001) compared with oral olanzapine when adding discontinuation to hospitalizations for mental disorder as a composite measure of effectiveness, as opposed to oral FGAs (adjusted HR 1.36, 95% CI 1.27-1.46, p < 0.0001) and LAI FGAs (adjusted HR 1.22, 95% CI 1.12-1.32, p < 0.0001). Most APs were as safe as oral olanzapine.

CONCLUSION

The effectiveness of LAI SGAs and clozapine appears to justify their use and are as safe as a recognized treatment (oral olanzapine) in Quebec (Canada).

Antipsychotic utilization trajectories three years after initiating or reinitiating treatment of schizophrenia: A state sequence analysis approach

OBJECTIVE

This study aims to describe the utilization patterns of antipsychotic (AP) medication in patients with schizophrenia (SCZ), three years after initiating or reinitiating a given AP.

METHODS

Based on medico-administrative information on patients living in Quebec (Canada), this retrospective cohort study included 6444 patients with a previous diagnosis of SCZ initiating or reinitiating AP medication between January 1, 2012, and December 31, 2014, with continuous coverage by public drug insurance. For each day of follow-up (1092 days), patient was either exposed to one of the chosen categories of APs, or to none. This patient's sequence of AP exposure overtime has been referred to as the "antipsychotic utilization trajectory". These trajectories were analyzed using a State Sequence Analysis, an innovative approach which provides useful visual information on the continuation and discontinuation patterns of use over time.

RESULTS

Clozapine and long-acting injectable second-generation APs had the best continuation and discontinuation patterns over 3 years among all other groups, including less switching of APs, while oral first-generation APs had the poorest patterns. These findings were comparable among incident and non-incident cohorts. Oral second-generation antipsychotics, excluding clozapine, had a poorer continuation and discontinuation pattern than long-acting injectable antipsychotics.

CONCLUSION

State Sequence Analysis provides a clear representation of treatment adherence in comparison with dichotomous indicators of adherence or discontinuation. Consequently, this innovative method has shed light on the impact of the AP chosen to initiate or reinitiate treatment in SCZ, which has been identified as a key factor for long-term treatment continuation and discontinuation.

Diagnostic conversion from unipolar to bipolar affective disorder-A population-based study

OBJECTIVES

It is essential to clinically distinguish bipolar affective disorder from unipolar affective disorders. However, patients previously diagnosed with unipolar affective disorder are sometimes later diagnosed with bipolar affective disorder, known as diagnostic conversion. Here we investigated diagnostic conversion using data from a nationwide population-based register.

METHODS

We obtained claims data from 2007 to 2020 in Korea's Health Insurance Review Agency database and identified a cohort of patients who were diagnosed with unipolar depression in 2009 without prior psychiatric diseases within the previous 2 years. We studied the rate of diagnostic conversion and risk factors, especially antidepressants.

RESULTS

About 6.5% of patients underwent diagnostic conversion during the observation period. Younger age at disease onset and usage of antidepressants increased the relative risk for diagnostic conversion. Patients using serotonin-norepinephrine reuptake inhibitors (SNRI) showed more than twice the risk compared to no usage of antidepressant.

LIMITATION

First, this study was based on the population-based register data. Thus, we defined the patient cohort diagnosed with unipolar depression with strict inclusion criteria. Second, the exposure time differed between different antidepressants. Third, we estimated the relative risk for diagnostic conversion compared to no use of antidepressants. Moreover, we could not rule out the potential influence of antidepressant polypharmacy.

CONCLUSION

We confirmed diagnostic conversion in some patients and identified younger age or usage of antidepressants, especially SNRI, as risk factors. Because unipolar and bipolar affective disorders show different disease courses or prognoses and have different treatment strategies, clinicians should be mindful of diagnostic conversion.

One-Year Clinical Outcomes Following Electroconvulsive Therapy for Patients with Schizophrenia: A Nationwide Health Insurance Data-Based Study

BACKGROUND

Although the use of electroconvulsive therapy (ECT) in the treatment of schizophrenia has decreased since the advent of antipsychotic drugs, ECT is still implemented in several clinical indications. However, a few population-based studies have examined its real-world effectiveness in schizophrenia.

METHODS

We used data from 2010 to 2019 from the Health Insurance Review and Assessment Service database in the Republic of Korea. We selected 380 schizophrenia patients having more than six ECT sessions and 1140 patient controls matched for age, sex, calendar year at entry, and the number of psychiatric hospitalizations before the time point of start of psychiatric hospitalization for ECT. Antipsychotic treatment discontinuation, psychiatric hospitalization, and direct medical costs were used as measures of clinical outcomes. Multiple regression analysis was used for any group-by-time interaction effect, and 1-year pre- and post-ECT periods were compared within and between the groups.

RESULTS

We found a significantly lower number of antipsychotic treatment discontinuations in the ECT group during the 1-year post-ECT period (t=2.195, p=0.028). A larger decrease was found in the number of psychiatric hospitalizations in the ECT group, with a group-by-time interaction effect (p=0.043). The direct medical costs in the 1-year pre- (t=-8.782, p<0.001) and post-ECT periods (t=-9.107, p<0.001) were higher in the ECT group than in the control group, with no significant change across both periods.

CONCLUSION

We found that the ECT group had a larger decrease in the number of psychiatric hospitalizations in the 1-year post-ECT period than the control group.