Trends in the Use of Long-Acting Injectable Antipsychotics in the Province of Manitoba, Canada

Long-Acting Injectable Second-Generation Antipsychotics vs Placebo and Their Oral Formulations in Acute Schizophrenia: A Systematic Review and Meta-Analysis of Randomized-Controlled-Trials

BACKGROUND AND HYPOTHESIS

Long-acting injectable antipsychotic drugs (LAIs) are mainly used for relapse prevention but could also be advantageous for acutely ill patients with schizophrenia.

STUDY DESIGN

We conducted a systematic review and meta-analysis of randomized-controlled-trials (RCTs) comparing the second-generation long-acting injectable antipsychotics (SGA-LAIs) olanzapine, risperidone, paliperidone, and aripiprazole with placebo or their oral counterparts in acutely ill patients with schizophrenia. We analyzed 23 efficacy and tolerability outcomes, with the primary outcome being overall symptoms of schizophrenia. The results were obtained through random effects, pairwise meta-analyses, and subgroup tests. The study quality was assessed using the Cochrane-Risk-of-Bias-Tool version-1.

STUDY RESULTS

Sixty-six studies with 16 457 participants were included in the analysis. Eleven studies compared second-generation long-acting injectable antipsychotics (SGA-LAIs) with a placebo, 54 compared second-generation oral antipsychotics (SGA-orals) with a placebo, and one compared an SGA-LAI (aripiprazole) with its oral formulation. All 4 SGA-LAIs reduced overall symptoms more than placebo, with mean standardized differences of -0.66 (95% CI: -0.90; -0.43) for olanzapine, -0.64 (-0.80; -0.48) for aripiprazole, -0.62 (-0.76; -0.48) for risperidone and -0.42 (-0.53; -0.31) for paliperidone. The side-effect profiles of the LAIs corresponded to the patterns known from the oral formulations. In subgroup tests compared to placebo, some side effects were less pronounced under LAIs than under their oral formulations.

CONCLUSIONS

SGA-LAIs effectively treat acute schizophrenia. Some side effects may be less frequent than under oral drugs, but due to the indirect nature of the comparisons, this finding must be confirmed by RCTs comparing LAIs and orals head-to-head.

10-Year Trends in Healthcare Spending among Patients with Schizophrenia in Alberta, Canada

OBJECTIVES

Schizophrenia is characterized by high levels of disability often resulting in increased healthcare utilization and spending. With expanding healthcare costs across all healthcare sectors, there is a need to understand how healthcare spending has changed over time. We conducted a population-based study using administrative health data from Alberta, Canada, to describe changes in medical complexity and direct healthcare spending among patients with schizophrenia over a 10-year period.

METHODS

A serial cross-sectional study from January 1, 2008, to December 31, 2017, was conducted to determine changes in demographic characteristics, medical complexity, and costs among all adults (18 years or older) with schizophrenia. Total healthcare spending and sector-specific costs attributable to hospitalizations, emergency department visits, practitioner billings, and prescriptions were calculated and compared over time.

RESULTS

Over the 10-year period the contact prevalence of patients with schizophrenia increased from 0.6% (n  =  16,183) to 1.0% (n  =  33,176) within the province. There was a marked change in medical complexity with the number of patients living with 3 or more comorbidities increasing from 33.0% to 47.3%. Direct annual healthcare costs increased 2-fold from 321 to 639 million CAD (493 million USD) with a 7-fold increase in medication expenditures over the 10-year time frame. As of 2017, spending on pharmaceutical treatment surpassed hospitalizations as the leading spending category in this population.

CONCLUSIONS

Healthcare spending among patients with schizophrenia continues to increase and may be partially attributable to growing rates of multimorbidity within this population. Although promising second-generation antipsychotic medications have entered the market, this has resulted in considerable changes in the distribution of healthcare spending over time. These findings will inform policy discussions around resource allocation and efforts to curb health spending while also improving care for patients with schizophrenia.

Long-Acting Injectable Antipsychotics in a Prescription Claims Data Source: A Validation Study

Background

The effectiveness of long-acting injectable antipsychotics (LAIAs) has been demonstrated in studies using prescription claims data. However, the validity of claims data for LAIAs has not been established.

Objective

We aimed to validate date dispensed, quantity dispensed and days supplied fields in prescription claims data, and to compare claims- and medical record-derived persistence estimates.

Methods

We evaluated LAIA dispensations in the Drug Programs Information Network prescription claims database from Manitoba, Canada against a random sample of medical records. Adults with one or more LAIA prescription between April 2015 and March 2016 were eligible. Results were stratified by LAIA type (first-generation LAIA, risperidone LAI or paliperidone LAI). Persistence estimates were assessed using Kaplan–Meier survival analysis and proportion of patients covered method.

Results

Claims data had high positive predictive value, ranging from 80.0% (95% CI 51.9–95.7) to 100.0% (95% CI 89.7–100.0), but low negative predictive value, ranging from 0.0% (95% CI 0.0–2.5) to 62.5% (95% CI 40.6–81.2). Quantity dispensed and days supplied exactly matched dose and dosing interval, respectively, for 99.7% and 97.1% of risperidone LAI doses, 100.0% and 76.6% of paliperidone doses, and 8.9% and 28.3% of first-generation LAIA doses. There were no significant differences in claims-derived versus medical record-derived persistence estimates.

Conclusions

Quantity dispensed and days supplied provide valid estimates of dose and dosing interval for second-generation LAIAs, but underestimated these parameters for first-generation LAIAs. However, a large proportion of medical record-confirmed doses were missing from claims data, and dose and dosing interval are underestimated in claims data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40801-022-00297-4.

Long-acting injectable antipsychotic (LAI) prescribing trends during COVID-19 restrictions in Canada: a retrospective observational study

BACKGROUND

The COVID-19 pandemic has had significant impacts on how mental health services are delivered to patients throughout Canada. The reduction of in-person healthcare services have created unique challenges for individuals with psychotic disorders that require regular clinic visits to administer and monitor long-acting injectable antipsychotic medications.

METHODS

To better understand how LAI usage was impacted, national and provincial patient-level longitudinal prescribing data from Canadian retail pharmacies were used to examine LAI prescribing practices during the pandemic. Prescribing data on new starts of medication, discontinuations of medications, switches between medications, antipsychotic name, concomitant medications, payer plan, gender and age were collected from January 2019 to December 2020 for individuals ≥18-years of age, and examined by month, as well as by distinct pandemic related epochs characterized by varying degrees of public awareness, incidence of COVID-19 infections and public health restrictions.

RESULTS

National, and provincial level data revealed that rates of LAI prescribing including new starts, discontinuations and switches between LAI products remained highly stable (i.e., no statistically significant differences) throughout the study period.

CONCLUSIONS

Equal numbers of LAI new starts and discontinuations prior to and during the pandemic suggests prescribing of LAI antipsychotics, for those already in care, continued unchanged throughout the pandemic. The observed consistency of LAI prescribing contrasts with other areas of healthcare, such as cardiovascular and diabetes care, which experienced decreases in medication prescribing during the COVID-19 pandemic.

Predictors of long-acting injectable antipsychotic prescription at discharge in patients with schizophrenia and other psychotic disorders

Long-acting injectable antipsychotics (LAIs) increase drug compliance and offer a reliable treatment option with stable pharmacokinetics. The aim of our study is to examine the rate and predictors of LAIs' prescription at discharge in inpatients with schizophrenia and other psychotic disorders. This retrospective study included 400 inpatients. Sociodemographic and clinical characteristics of the patients, the treatments applied in the past and prescribed at discharge were obtained from the hospitalization files. We compared these characteristics of those who were given LAI treatment at discharge to the patients who were given oral treatments. Thirty-nine percent of the patients were prescribed a LAI at discharge. Duration of illness was longer, and number of previous hospitalizations was higher in the LAI group. Nonadherence to the antipsychotics before the hospitalization, the previous history of LAI use, lack of insight at the admission and no previous antidepressant use were found as independent contributors to LAI prescription as the treatment of discharge in logistic regression analysis. Our study showed that LAIs are used at a high rate in our clinic; however, they are still initiated at a later stage, mostly in chronic patients with a lack of insight and compliance at admission.

Impact of age and gender on paliperidone exposure in patients after administration of long-acting injectable formulations-an observational study using blood samples from 1223 patients

PURPOSE

Paliperidone palmitate is an antipsychotic medication available as long-acting injectable (LAI) formulations. The aim of this study was to investigate the effect of age and gender on paliperidone exposure after administration of LAI formulations.

METHODS

Data on serum concentrations of paliperidone from patients using LAI during were included retrospectively from a therapeutic drug monitoring (TDM) service. Information about dose was obtained from the requisition forms. As a measure of exposure, daily dose-adjusted serum concentration (C/D ratio) was used. Based on initial analysis of C/D ratios versus age, a breaking point close to 50 years was observed, thus deciding the grouping of patients as older (≥50 years) or younger (15-49 years). Linear mixed model analyses, allowing multiple measurements per patients, were used.

RESULTS

In total, 1223 patients were included, whereof 1158 patients used paliperidone LAI in once-monthly intervals. In these patients (27.9% older), older patients had significantly higher paliperidone C/D ratio than younger patients (+20%, p<0.001). Compared to males, females had higher C/D ratio (+14%; p<0.001). Subsequently, older female users of once-monthly LAI intervals had 41% higher paliperidone C/D ratios compared to younger males (15.0 vs. 21.2 nM/mg; p<0.001). Compared to females aged 21-30 years, females with high age (≥70 years) had at least 105% higher paliperidone C/D ratio (p<0.001).

CONCLUSION

The present study shows that older age and female gender are associated with higher paliperidone exposure than younger age and males, respectively. Particularly, older female patients (>50 years) are likely exposed to high concentration and cautious dosing in this subgroup is required.

Patterns of long acting injectable antipsychotic use and associated clinical factors in schizophrenia among 15 Asian countries and region

INTRODUCTION

Patterns of clinical use of long-acting injectable (LAI) antipsychotic drugs in many countries, especially in Asia, for treatment of patients diagnosed with chronic psychotic disorders including schizophrenia are not well established.

METHODS

Within an extensive research consortium, we evaluated prescription rates for first- (FGA) and second-generation antipsychotic (SGA) LAI drugs and their clinical correlates among 3557 subjects diagnosed with schizophrenia across 15 Asian countries and region.

RESULTS

Overall, an average of 17.9% (638/3557; range: 0.0%-44.9%) of treated subjects were prescribed LAI antipsychotics. Those given LAI vs orally administered agents were significantly older, had multiple hospitalizations, received multiple antipsychotics more often, at 32.4% higher doses, were more likely to manifest disorganized behavior or aggression, had somewhat superior psychosocial functioning and less negative symptoms, but were more likely to be hospitalized, with higher BMI, and more tremor. Being prescribed an FGA vs SGA LAI agent was associated with male sex, aggression, disorganization, hospitalization, multiple antipsychotics, higher doses, with similar risks of adverse neurological or metabolic effects. Rates of use of LAI antipsychotic drugs to treat patients diagnosed with schizophrenia varied by more than 40-fold among Asian countries and given to an average of 17.9% of treated schizophrenia patients. We identified the differences in the clinical profiles and treatment characteristics of patients who were receiving FGA-LAI and SGA-LAI medications.

DISCUSSION

These findings behoove clinicians to be mindful when evaluating patients' need to be on LAI antipsychotics amidst multifaceted considerations, especially downstream adverse events such as metabolic and extrapyramidal side effects.