Prescribing pattern of antipsychotic drugs during the years 1996-2010: a population-based database study in Europe with a focus on torsadogenic drugs

Guideline adherence for cardiometabolic monitoring of patients prescribed antipsychotic medications in primary care: a retrospective observational study

BACKGROUND

Despite their known effectiveness, antipsychotics possess significant cardiometabolic adverse event profiles. Guidelines emphasise routine monitoring, however, practices are known to be suboptimal.

AIM

To investigate the level of cardiometabolic monitoring among people prescribed antipsychotic therapy in primary care, and patient-related factors that may influence monitoring patterns.

METHOD

Data were collected for patients with mental disorders and prescribed antipsychotics at two general practices in England (February 2016-February 2021). The main outcome measures were the proportion of patients with evidence of monitoring for cardiometabolic parameters (body composition, anthropometrics, lipids, glucose outcomes). Regression analysis was used to explore factors predicting monitoring practices.

RESULTS

Data from 497 patients were included. The proportion of patients receiving cardiometabolic monitoring at least once yearly varied across different parameters. Patients were mostly monitored for BP (92.0%), body weight (BMI > 85.0%) and HDL (72.0%), but to a lesser extent for other lipid parameters (non-HDL < 2.0%) and blood glucose (< 2.0%). Ageing (OR:2.0-7.0, p < 0.001) and chronic conditions (e.g., CVD and Type 2 DM, p < 0.05) were associated with frequent cardiometabolic monitoring. Conversely, antipsychotics with high metabolic risks (olanzapine), patients prescribed antipsychotic polypharmacy (≥ 2 antipsychotics) and cardiometabolic dysregulations (e.g., dyslipidaemias) did not improve monitoring frequencies.

CONCLUSION

Cardiometabolic health monitoring was generally infrequent, irregular, and did not change in response to abnormal test results or antipsychotic treatment with high cardiometabolic risks, suggesting more efforts need to be made to ensure the guidelines for cardiometabolic monitoring are followed. Future studies should investigate practices by using a large UK primary care database.

[Antipsychotic prescription prevalence and metabolic monitoring of patients under chronic treatment]

Introduction

Antipsychotics agents increase morbidity and mortality due to their metabolic impact. Information on its prescription and follow-up is scarce. The objective of this study was to estimate the chronic antipsychotic prescription prevalence and to evaluate the metabolic monitoring of patients treated with these medications.

Methods

We examined a retrospective cohort of patients older than 18 years treated in the outpatient setting of a hospital in Argentina. The crude and adjusted prevalence of chronic antipsychotic prescription was estimated by indirect standardization of the World Health Organization population, with its confidence interval (95%). It was evaluated whether the patients had biochemical determinations, systolic blood pressure (SBP), and body mass index (BMI) at the beginning and at 12 months of their treatment.

Results

The crude antipsychotic prescription prevalence was 23.8 ‰ (95% CI 23.0 - 24.6) and the adjusted prevalence was 10.1 ‰ (95% CI 9.5-10.7). 3702 patients were evaluated. The male:female ratio was 0.6. Median age 77.5 years (IQR 25-75: 59.5-86.1). Quetiapine was the most frequently prescribed. Initial determinations: Lipid profile 1804 (48.7%), blood glucose 2034 (54.9%), SBP 2546 (68.8%) and BMI 1584 (42.8%). At 12 months: Lipid profile 680 (18.4%), blood glucose 898 (24.3%), SAT 1609 (43.5%), and BMI 1584 (21.7%).

Conclusions

We observed a higher prevalence of atypical antipsychotic prescription in the elderly and female population and scarce registry of biochemical determinations for adverse effects follow-up.

[Antipsychotic prescription prevalence and metabolic monitoring of patients under chronic treatment]

INTRODUCTION

Antipsychotics agents increase morbidity and mortality due to their metabolic impact. Information on its prescription and follow-up is scarce. The objective of this study was to estimate the chronic antipsychotic prescription prevalence and to evaluate the metabolic monitoring of patients treated with these medications.

METHODS

We examined a retrospective cohort of patients older than 18 years treated in the outpatient setting of a hospital in Argentina. The crude and adjusted prevalence of chronic antipsychotic prescription was estimated by indirect standardization of the World Health Organization population, with its confidence interval (95%). It was evaluated whether the patients had biochemical determinations, systolic blood pressure (SBP), and body mass index (BMI) at the beginning and at 12 months of their treatment.

RESULTS

The crude antipsychotic prescription prevalence was 23.8 ‰ (95% CI 23.0 - 24.6) and the adjusted prevalence was 10.1 ‰ (95% CI 9.5-10.7). 3702 patients were evaluated. The male:female ratio was 0.6. Median age 77.5 years (IQR 25-75: 59.5-86.1). Quetiapine was the most frequently prescribed. Initial determinations: Lipid profile 1804 (48.7%), blood glucose 2034 (54.9%), SBP 2546 (68.8%) and BMI 1584 (42.8%). At 12 months: Lipid profile 680 (18.4%), blood glucose 898 (24.3%), SAT 1609 (43.5%), and BMI 1584 (21.7%).

CONCLUSIONS

We observed a higher prevalence of atypical antipsychotic prescription in the elderly and female population and scarce registry of biochemical determinations for adverse effects follow-up.

Multi-analyte LC-MS/MS quantification of 38 antipsychotics and metabolites in plasma: Method validation & application to routine analyses

The past decades have seen a rise in the prescription of antipsychotic drugs in the European population, despite the risk of extra-pyramidal, metabolic and cardiac side effects. A multi-analyte liquid chromatography - triple quadrupole mass spectrometry method was developed for the quantification of 38 antipsychotic drugs in plasma. Samples were extracted by a straightforward liquid-liquid extraction with methyl-tertiary-butyl-ether and the compounds of interest were chromatographically separated within 6 min. Calibration curves covered the recommended therapeutic range for all compounds, in addition to sub- and supratherapeutic concentrations for most. The method was successfully validated according to the European Medicines Agency guidelines on bioanalytical method validation. Analysis of medico-legal samples confirmed the relatively common use of the second generation antipsychotics quetiapine and olanzapine, as well as the continued presence of the first generation antipsychotic haloperidol.

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.

Haloperidol Interactions with the dop-3 Receptor in Caenorhabditis elegans

Haloperidol is a typical antipsychotic drug commonly used to treat a broad range of psychiatric disorders related to dysregulations in the neurotransmitter dopamine (DA). DA modulates important physiologic functions and perturbations in Caenorhabditis elegans (C. elegans) and, its signaling have been associated with alterations in behavioral, molecular, and morphologic properties in C. elegans. Here, we evaluated the possible involvement of dopaminergic receptors in the onset of these alterations followed by haloperidol exposure. Haloperidol increased lifespan and decreased locomotor behavior (basal slowing response, BSR, and locomotion speed via forward speed) of the worms. Moreover, locomotion speed recovered to basal conditions upon haloperidol withdrawal. Haloperidol also decreased DA levels, but it did not alter neither dop-1, dop-2, and dop-3 gene expression, nor CEP dopaminergic neurons' morphology. These effects are likely due to haloperidol's antagonism of the D2-type DA receptor, dop-3. Furthermore, this antagonism appears to affect mechanistic pathways involved in the modulation and signaling of neurotransmitters such as octopamine, acetylcholine, and GABA, which may underlie at least in part haloperidol's effects. These pathways are conserved in vertebrates and have been implicated in a range of disorders. Our novel findings demonstrate that the dop-3 receptor plays an important role in the effects of haloperidol.

'Use of antipsychotics in children and adolescents: a picture from the ARITMO population-based European cohort study'

AIMS

Prevalence of the use of antipsychotics (APs) in the paediatric population is globally increasing. The aim of this study was to describe multinational trends and patterns in AP use in children and adolescents in Europe.

METHODS

This was a dynamic retrospective cohort study comprising all children and adolescents (⩽18 years of age). Data were extracted from five population-based electronic healthcare databases in Europe (Denmark, Germany, Italy, the Netherlands and United Kingdom) from 2000 to 2010. Yearly prevalence and incidence of AP use was expressed per 1000 person-years (PYs).

RESULTS

Prevalence increased from 1.44 to 3.41/1000 PYs (2008) in Denmark and from 2.07 to 4.35/1000 PYs in the NL (2009), moderately increased from 2.8 to 3.24/1000 in UK (2009) and from 1.53 to 1.74/1000 PYs in Germany (2008) and remained low from 0.61 to 0.34/1000 PYs in Italy (2010). Similarly, incidence rates increased from 0.69 to 1.52/1000 PYs in Denmark and from 0.86 to 1.49/1000 PYs in the NL, stabilised from 2.29 to 2.37/1000 PYs in the UK and from 0.79 to 0.80/1000 PYs in Germany and remained low from 0.32 to 0.2/1000 PYs in Italy. AP use was highest in 15-18 year olds and in boys compared to girls. Yet, the use observed in the 5-9 year olds was found to be comparatively high in the NL. Prescriptions of second generation APs, especially risperidone, were privileged but the first generation APs were still prescribed in the youngest.

CONCLUSIONS

A steady increase in AP use in children and adolescents was observed essentially in the NL and Denmark. The use in Germany and Italy was lowest among countries. The use of APs under 9 years of age underlines their off-label use and should be carefully monitored as the risk/benefit ratio of these medications remains unclear in young children. AP use was altogether lower in Europe as compared to that reported in North America.

Prolonged use of antipsychotic medications in long-term aged care in Australia: a snapshot from the HALT project

OBJECTIVES

Use of antipsychotic drugs in long-term aged care (LTC) is prevalent and commonly exceeds the recommended duration, but contributors to this problem are not well understood. The objective of this study is to provide a snapshot of the features of and contributors to prolonged use of antipsychotic medications (>12 weeks) among a sample of LTC residents.

DESIGN

We present retrospective and baseline data collected for the Australian Halting Antipsychotic Use in Long-Term Care (HALT) single-arm longitudinal deprescribing trial.

SETTING

Twenty-four long-term care facilities in Sydney, Australia.

PARTICIPANTS

The HALT study included 146 older people living in 24 Sydney LTC homes who had been prescribed a regular antipsychotic medication for at least 3 months at baseline.

MEASUREMENTS

Detailed file audit was conducted to identify the date and indication recorded at initial prescription, consenting practices, longitudinal course of prescribing, and recommendations for review of antipsychotic medication. Behavioural and psychological symptoms of dementia (BPSD) and functional dependence at baseline were assessed via LTC staff interview. Cognition at baseline was assessed in a participant interview (where possible).

RESULTS

Antipsychotics were prescribed for 2.2 years on average despite recommendations by a doctor or pharmacist for review in 62% of cases. Consent for antipsychotic prescription was accessible for only one case and contraindications for use were common. Longer use of antipsychotics was independently associated with higher dose of the antipsychotic drug and greater apathy, but not with other BPSD.

CONCLUSION

Antipsychotic medications appeared to be prescribed in this sample as a maintenance treatment in the absence of active indicated symptoms and without informed consent. Standard interventions, including recommendations for review, had been insufficient to ensure evidence-based prescribing.

Mortality Risk Associated with Haloperidol Use Compared with Other Antipsychotics: An 11-Year Population-Based Propensity-Score-Matched Cohort Study

BACKGROUND

Haloperidol remains a frequently prescribed first-generation antipsychotic. However, haloperidol-associated mortality risk by all causes, cardiovascular disease (CVD), and pneumonia compared with other antipsychotics is unknown.

OBJECTIVE

This study investigated the mortality risk associated with long-term haloperidol treatment versus that with other antipsychotics.

METHODS

We identified incident antipsychotic users from 2004 to 2014 in the Clinical Data Analysis and Reporting System (CDARS), a population-based clinical database managed by the Hong Kong Hospital Authority. We included patients who were aged ≥ 18 and received antipsychotics for any indication apart from terminal illnesses or management of acute behavioural disturbance. Patients on haloperidol and other antipsychotic agents (risperidone, quetiapine, olanzapine, chlorpromazine, aripiprazole, sulpiride, amisulpride, or trifluoperazine) were matched by propensity score. Hazard ratios (HRs) for all-cause mortality and death due to CVD and pneumonia were estimated with 95% confidence intervals (CIs) using a Cox proportional hazards model.

RESULTS

In total, 136,593 users of antipsychotics were included. During a mean follow-up of 3.2 years, the incidence of all-cause mortality ranged from 186.8/1000 person-years for haloperidol to 10.4/1000 person-years for trifluoperazine. The risk of all-cause mortality was lower with non-haloperidol antipsychotics than with haloperidol, with HRs ranging from 0.68 (95% CI 0.64-0.72 [chlorpromazine]) to 0.43 (95% CI 0.36-0.53 [trifluoperazine]). Risperidone, quetiapine, sulpiride, chlorpromazine, aripiprazole, and trifluoperazine were associated with a significantly lower risk of pneumonia-related mortality. A significantly lower risk of CVD mortality was observed for risperidone, sulpiride, chlorpromazine, and quetiapine.

CONCLUSION

Haloperidol was associated with increased overall mortality when compared with other antipsychotics in long-term follow-up. Treatment with haloperidol should be carefully considered, especially in older patients and patients at risk of CVD or pneumonia, since the risk of death appears to be lower with non-haloperidol agents.

Coprescription of QT interval-prolonging antipsychotics with potentially interacting medications in Thailand

Background

The US FDA has designated pimozide, thioridazine, and ziprasidone as contraindicated for patients at risk of QT interval prolongation, and assigned haloperidol, olanzapine, paliperidone, quetiapine, and risperidone as associated with a significant risk of QT prolongation. This study aimed to examine trends and hospital variations in concomitant prescribing among these eight selected antipsychotics, and coprescription with interacting drugs known to increase QT prolongation risk.

Methods

Data on outpatient antipsychotic prescriptions during 2012-2015 were obtained from 16 general hospitals and 10 university hospitals nationwide. A time-series analysis was used for estimating trends in coprescription that led to drug interactions.

Results

Coprescribing among the eight antipsychotics ranged from 7.5% for quetiapine to 33.1% for thioridazine. The rate of coprescription with contraindicated interacting drugs was 9.7% for thioridazine and 21.9% for pimozide, and increased by 1.1 and 1.4 percentage points (% pt.) yearly for thioridazine in general and university hospitals, respectively. Coprescribing with interacting drugs with precautions was 2.8% for quetiapine, 7.4% for ziprasidone, and 27.9% for risperidone; these percentages increased yearly by 1.7% pt. for ziprasidone and 2.6% pt. for risperidone in general hospitals, as well as by 1.0% pt. for risperidone in university hospitals. The median proportion of patients exposed to a QT-prolonging interaction was 12.3% across hospitals (interquartile range, 9.9-19.5%). Wide interhospital variation was found in percentages of drug interactions among patients receiving thioridazine, ziprasidone, paliperidone, or olanzapine in general hospitals, and among patients receiving paliperidone or pimozide in university hospitals.

Conclusions

Coprescription of antipsychotics with interacting drugs that could increase the risk of QT prolongation was common in Thailand, and thioridazine, ziprasidone, and risperidone showed increasing trends. We urge the incorporation of a unified list of QT-prolonging antipsychotics and interacting drugs into a computerized drug interaction warning system, and existing national rational drug use campaigns should cover this important issue.

Trends in utilization and dosing of antipsychotic drugs in Scandinavia: Comparison of 2006 and 2016

AIMS

The aim of this study was to investigate time trends in dosing and prevalence of antipsychotic prescriptions in Scandinavia.

METHODS

We retrieved data on antipsychotic use between 2006 and 2016 from Danish, Norwegian and Swedish national prescription registers. For each antipsychotic, we calculated prevalence of use and mean doses, overall and for specific age groups (young, adults and elderly).

RESULTS

Antipsychotic use in Scandinavia increased from 16.5 to 17.2 users/1000 inhabitants between 2006 and 2016 (+2.4%, annual change: 0.07 users/1000 inhabitants/year, 95% CI: 0.02-0.20, P = 0.02). In 2006, chlorprothixene and levomepromazine were the most commonly used antipsychotics. By 2016, quetiapine was the most used antipsychotic in all three countries and across all age groups, with an overall 1-year prevalence of 4.05-9.97 users/1000 inhabitants (annual change: 0.57 users/1000 inhabitants/year, 95% CI: 0.54-0.60, P < 0.001). Quetiapine showed a marked decrease in mean doses during the 11-year study period (0.46-0.28 defined daily doses (DDD)/user/day: 39.1%, -0.02 DDD/user/day/year, 95% CI: -0.020 to -0.015, P < 0.001). In 2016, the highest mean doses were seen for clozapine (0.90-1.07 DDD/user/day) and olanzapine (0.66-0.88 DDD/user/day).

CONCLUSIONS

There is an increased prevalence of antipsychotic prescriptions that coincides with low and/or decreasing mean doses of the majority of commonly used antipsychotics in Scandinavia. Of all antipsychotics, this development was most pronounced for quetiapine. Reasons for and consequences of increased antipsychotic use that lasts shorter periods of time requires further study.

Use of psychoactive drugs predicts functional disability among older adults

OBJECTIVE

Investigate whether the use of psychoactive drugs would be a predictor of incidence of functional disability among seniors living in community.

METHODS

It is a population-based longitudinal study, developed between January 1, 1997 and December 31, 2011, with older adults living in community. The association between the use of psychoactive drugs and the development of functional disability for instrumental (IADLs) and basic (BADLs) activities of daily living was tested using the extended Cox proportional hazards model, which considers the measure of exposure of interest throughout the follow-up period. The analyses were stratified by sex and adjusted by sociodemographic characteristics, health behavior and health conditions.

RESULTS

After multivariate adjustment, the use of two or more psychoactive drugs in the female stratum was associated with disability for both IADLs (HR = 1.58; 95%CI 1.17-2.13) and BADLs (HR = 1.43; 95%CI 1.05-1.94), the use of benzodiazepines was associated with disability for IADLs (HR = 1.32; 95%CI 1.07-1.62), and the use of antidepressants was associated with disability for both IADLs (HR = 1.51; 95%CI 1.16-1.98) and BADLs (HR = 1.44; 95%CI 1.10-1.90). In the male stratum, the use of antipsychotics was associated with disability for IADLs (HR = 3.14; 95%CI 1.49-6.59).

CONCLUSIONS

The study showed a prospective association between the use of psychoactive drugs and functional disability. These results indicate the need to carefully assess the prescription of psychoactive drugs for older adults and monitor their usage in order to detect damages to the health of users.

All-cause mortality and antipsychotic use among elderly persons with high baseline cardiovascular and cerebrovascular risk: a multi-center retrospective cohort study in Italy

BACKGROUND

Little is known about the comparative risk of death with atypical or conventional antipsychotics (APs) among persons with cardiovascular or cerebrovascular disease (CCD).

RESEARCH DESIGN AND METHODS

A cohort study was conducted using five Italian claims databases. New atypical AP users with CCD aged ≥65 (reference) were matched to new conventional AP users. Mortality per 100 person-years (PYs) and hazard ratios (HR), estimated using Cox models, were reported. Incidence and risk of death were estimated for persons having drug-drug interactions. Outcome occurrence was evaluated 180 days after AP initiation.

RESULTS

Overall 24,711 and 27,051 elderly new conventional and atypical AP users were identified. The mortality rate was 51.3 and 38.5 deaths per 100 PYs for conventional and atypical AP users. Mortality risk was 1.33 (95%CI: 1.27-1.39) for conventional APs. There was no increased mortality risk with single drug-drug interactions (DDIs) vs. no DDI. AP users with ≥1 DDI had a 29% higher mortality risk compared to no DDI in the first 90 days of treatment (HR: 1.29 (95% CI: 1.00-1.67)).

CONCLUSIONS

Conventional APs had a higher risk of death than atypical APs among elderly persons with CCD. Having ≥1 DDI was associated with an increased risk of death.

Drug-induced life-threatening arrhythmias and sudden cardiac death: A clinical perspective of long QT, short QT and Brugada syndromes

Sudden cardiac death is a major public health challenge, which can be caused by genetic or acquired structural or electrophysiological abnormalities. These abnormalities include hereditary channelopathies: long QT, short QT and Brugada syndromes. These syndromes are a notable concern, particularly in young people, due to their high propensity for severe ventricular arrhythmias and sudden cardiac death. Current evidence suggests the involvement of an increasing number of drugs in acquired forms of long QT and Brugada syndromes. However, drug-induced short QT syndrome is still a rarely reported condition. Therefore, there has been speculation on its clinical significance, since few fatal arrhythmias and sudden cardiac death cases have been described so far. Drug-induced proarrhythmia is a growing challenge for physicians, regulatory agencies and the pharmaceutical industry. Physicians should weigh the risks of potentially fatal outcomes against the therapeutic benefits, when making decisions about drug prescriptions. Growing concerns about its safety and the need for more accurate predictive models for drug-induced fatal outcomes justify further research in these fields. The aim of this article is to comprehensively and critically review the recently published evidence with regard to drug-induced life-threatening arrhythmias and sudden cardiac death. This article will take into account the provision of data to physicians that are useful in the identification of the culprit drugs, and thus, contribute to the prompt recognition and management of these serious clinical conditions.

Effects of atypical antipsychotic drugs on QT interval in patients with mental disorders

Background

Drug-induced QT prolongation is associated with higher risk of cardiac arrhythmias and cardiovascular mortality. We investigated the effects of atypical antipsychotic drugs on QT interval in children and adults with mental disorders.

Methods

We conducted random-effects direct frequentist meta-analyses of aggregate data from randomized controlled trials (RCT) and appraised the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Our search in PubMed, EMBASE, the Cochrane Library, clinicaltrials.gov, and PharmaPendium up to October 2017 identified studies that examined aripiprazole, quetiapine, risperidone, olanzapine, ziprasidone and brexpiprazole.

Results

Low quality evidence suggests that aripiprazole (four meta-analyses and twelve RCTs), brexpiprazole (one systematic review and four RCTs) or olanzapine (five meta-analyses and twenty RCTs) do not increase QT interval. Low quality evidence suggests that ziprasidone (five meta-analyses and 11 RCTs) increases QT interval and the rates of QT prolongation while risperidone (four meta-analyses, 70 RCTs) and quetiapine (two meta-analyses and seven RCTs) are associated with QT prolongation and greater odds of torsades de pointes ventricular tachycardia especially in cases of drug overdose.

Conclusions

The main conclusion of our study is that in people with mental disorders and under treatment with atypical antipsychotic drugs, in order to avoid QT prolongation and reduce the risk of ventricular tachycardia clinicians may recommend aripiprazole, brexpiprazole or olanzapine in licensed doses. Long-term comparative safety needs to be established.

Outcome reporting bias in randomized-controlled trials investigating antipsychotic drugs

Recent literature hints that outcomes of clinical trials in medicine are selectively reported. If applicable to psychotic disorders, such bias would jeopardize the reliability of randomized clinical trials (RCTs) investigating antipsychotics and thus their extrapolation to clinical practice. We therefore comprehensively examined outcome reporting bias in RCTs of antipsychotic drugs by a systematic review of prespecified outcomes on ClinicalTrials.gov records of RCTs investigating antipsychotic drugs in schizophrenia and schizoaffective disorder between 1 January 2006 and 31 December 2013. These outcomes were compared with outcomes published in scientific journals. Our primary outcome measure was concordance between prespecified and published outcomes; secondary outcome measures included outcome modifications on ClinicalTrials.gov after trial inception and the effects of funding source and directionality of results on record adherence. Of the 48 RCTs, 85% did not fully adhere to the prespecified outcomes. Discrepancies between prespecified and published outcomes were found in 23% of RCTs for primary outcomes, whereas 81% of RCTs had at least one secondary outcome non-reported, newly introduced, or changed to a primary outcome in the respective publication. In total, 14% of primary and 44% of secondary prespecified outcomes were modified after trial initiation. Neither funding source (P=0.60) nor directionality of the RCT results (P=0.10) impacted ClinicalTrials.gov record adherence. Finally, the number of published safety endpoints (N=335) exceeded the number of prespecified safety outcomes by 5.5 fold. We conclude that RCTs investigating antipsychotic drugs suffer from substantial outcome reporting bias and offer suggestions to both monitor and limit such bias in the future.

Combining evidence from multiple electronic health care databases: performances of one-stage and two-stage meta-analysis in matched case-control studies

PURPOSE

Clustering of patients in databases is usually ignored in one-stage meta-analysis of multi-database studies using matched case-control data. The aim of this study was to compare bias and efficiency of such a one-stage meta-analysis with a two-stage meta-analysis.

METHODS

First, we compared the approaches by generating matched case-control data under 5 simulated scenarios, built by varying: (1) the exposure-outcome association; (2) its variability among databases; (3) the confounding strength of one covariate on this association; (4) its variability; and (5) the (heterogeneous) confounding strength of two covariates. Second, we made the same comparison using empirical data from the ARITMO project, a multiple database study investigating the risk of ventricular arrhythmia following the use of medications with arrhythmogenic potential. In our study, we specifically investigated the effect of current use of promethazine.

RESULTS

Bias increased for one-stage meta-analysis with increasing (1) between-database variance of exposure effect and (2) heterogeneous confounding generated by two covariates. The efficiency of one-stage meta-analysis was slightly lower than that of two-stage meta-analysis for the majority of investigated scenarios. Based on ARITMO data, there were no evident differences between one-stage (OR = 1.50, CI = [1.08; 2.08]) and two-stage (OR = 1.55, CI = [1.12; 2.16]) approaches.

CONCLUSIONS

When the effect of interest is heterogeneous, a one-stage meta-analysis ignoring clustering gives biased estimates. Two-stage meta-analysis generates estimates at least as accurate and precise as one-stage meta-analysis. However, in a study using small databases and rare exposures and/or outcomes, a correct one-stage meta-analysis becomes essential.

Prescribing pattern of antipsychotic drugs during the years 1996-2010: a population-based database study in Europe with a focus on torsadogenic drugs

INTRODUCTION

Antipsychotic drugs (APDs) are used to treat several mental illnesses. Some APDs have long been known to be associated with QT prolongation, potentially leading to torsades de pointes (TdP) and sudden cardiac death (SCD). In 2005, thioridazine was withdrawn because of the risk of SCD, bringing further attention to the arrhythmogenic potential of APDs.

AIM

The aim of the current study was to evaluate the use of APDs in five European countries during the years 1996-2010.

METHODS

A cohort study was conducted using prescription/dispensing data from seven healthcare databases [the AARHUS University Hospital Database (Denmark), the German Pharmacoepidemiological Research Database (GePaRD) (Germany), Health Search Database/Thales (HSD) and Emilia Romagna Regional Database (ERD) (Italy), PHARMO Database Network and Integrated Primary Care Information (IPCI) (the Netherlands) and The Health Improvement Network (THIN) (the UK), covering a population of 27 million individuals. The annual prescription rate of APDs was measured overall and for individual medications. APDs were classified as torsadogenic according to the Arizona-CERT list. All analyses were stratified by age, gender and calendar year.

RESULTS

A total of 559 276 person-years (PYs) of exposure to APDs was captured. The crude annual prescription rate of APD use ranged from 3.0/1000 PYs in ERD to 7.7/1000 PYs in AARHUS. Among APDs with established torsadogenic potential, thioridazine was the most frequently used medication in the UK. Haloperidol was commonly prescribed in Italy and the Netherlands. The use of APDs with torsadogenic potential was much higher in elderly patients.

CONCLUSIONS

Substantial use of APDs with torsadogenic potential has been reported in Europe in recent years, in spite of increasing concerns about their arrhythmogenic potential. This use was even greater in elderly patients, who are at higher risk of SCD.