Antiepileptic drug use in seven electronic health record databases in Europe: A methodologic comparison

Therapeutic drug monitoring in India: A strength, weakness, opportunity and threats analysis

Over the last three to four decades, Therapeutic Drug Monitoring (TDM) has shaped itself as therapeutic drug management, an integral component of precision medicine. The practice of TDM is not extensive in India, despite being one of the fastest-growing economies in the world. It is currently limited to a few academic medical centres and teaching hospitals. Apart from the immunosuppressive drugs, several other therapeutic areas, such as anticancer, antifungal, antibiotic and antitubercular, have demonstrated great potential to improve patient outcomes in Indian settings. Factors such as the higher prevalence of nutritional deficiencies, tropical diseases, widespread use of alternative medicines, unalike pharmacogenomics and sparse population-specific data available on therapeutic ranges of several drugs make the population of this subcontinent unique regarding the relevance of TDM. Despite the impact of TDM in clinical science and its widespread application, TDM has failed to receive the attention it deserves in India. This review intends to bring out a strength, weakness, opportunity and threats (SWOT) analysis for TDM in India so that appropriate steps for fostering the growth of TDM could be envisioned. The need of the hour is the creation of a cooperative group including all the stakeholders, such as TDM professionals, clinicians and the government and devising a National Action Plan to strengthen TDM. Nodal TDM centres should be established, and pilot programmes should be rolled out to identify the thrust areas for TDM in the country, capacity building and creating awareness to integrate TDM into mainstream clinical medicine.

Treatment-emergent adverse events and antiseizure medication actual drug load

OBJECTIVE

The correlation between treatment-emergent adverse events (TEAE) and antiseizure medication (ASM) drug load is a controversial topic. Previous studies used daily defined dosage (DDD) to measure drug load. We aim to assess if ASM adjusted to body weight and plasma levels were associated with TEAE.

METHODS

We analyzed clinical visits of a trial on therapeutic drug monitoring in outpatients with epilepsy. TEAE, treatment, and its changes, as well as ASM plasma levels, were recorded at each visit. Each medication level was stratified according to its position in relation to its proposed reference range (below, in the lower half, upper half, or above).

RESULTS

We analyzed 424 visits (151 participants). Treatment-emergent adverse events were reported in 84 (20%) visits. There was no significant difference when comparing visits with TEAE with those without TEAE in terms of ASM drug load (calculated with DDD), corrected for body weight, their changes since the last visit, as well as summed plasma levels compared to reference ranges.

SIGNIFICANCE

Actual drug load seems not to represent a major determinant of TEAE recorded during routine visits, even when accounting thoroughly for the patient's exposure to the treatment. The use of structured questionnaires and neuropsychometric tests may assess more accurately the potential consequences of drug loads.

Changes in antiepileptic drug prescriptions over a decade in childbearing women in Lombardy region, Italy

AIMS

To describe the antiepileptic drug (AED) prescription pattern in pregnant women and women of childbearing age in the 2010-2019 period in the Lombardy region, Italy.

METHODS

The Lombardy region administrative healthcare databases (2010-2019) were analysed. AEDs were classified as drugs belonging to the N03A subgroup of the Anatomical Therapeutic Chemical Classification System. Women aged 15-49 years were considered as being of childbearing age, while exposure during pregnancy was estimated taking into account the 12 months before delivery (International Classification of Diseases, Ninth Revision, Clinical Modification, ICD-9-CM codes in the diagnosis record from 650 to 659).

RESULTS

During 2019, 16 605 women of childbearing age (prevalence: 14.8‰) received at least 1 AED prescription. Pregabalin was the most widely used antiepileptic in women of childbearing age (22.3%), followed by valproic acid (20.0%). In 2010, the prevalence of valproic acid prescription to women of childbearing age was 30.2%; in 2019 this was 20.0%. In pregnant women, this prevalence was 24.9% in 2010 and 14.1% in 2019. Starting from 2017, levetiracetam and lamotrigine were the most commonly drugs prescribed to pregnant women.

CONCLUSION

Despite the decrease in valproic acid prescription over time, this drug is still among the most used AEDs, in particular in women of childbearing age. Educational interventions for healthcare professionals and women are needed in order to reduce the risk of unplanned pregnancy.

Prescription patterns and dosages of antiepileptic drugs in prevalent patients with epilepsy in Taiwan: A nationwide retrospective cross-sectional study

OBJECTIVE

To evaluate the prescription patterns and prescribed daily dose (PDD)/defined daily dose (DDD) ratios of antiepileptic drugs (AEDs) in prevalent patients with epilepsy in Taiwan.

MATERIALS AND METHODS

A nationwide retrospective cross-sectional study was conducted for prevalent patients with epilepsy in 2016 using the Taiwanese National Health Insurance Research Database. The prescription records of AEDs of all prevalent patients with epilepsy were retrieved. The mean PDDs and PDD/DDD ratios of AEDs in adult patients were obtained to evaluate dosing adequacy. A chi-square test and two-sample t test were used to analyze the differences in AED prescription patterns and dosages, respectively, among patients with different ages, sexes, comorbidities, and therapeutic approaches.

RESULTS

A total of 118,937 prevalent patients with epilepsy were enrolled. The predominant therapeutic approach was monotherapy, especially in the elder adults, accounting for 82.9% of elder adult patients with epilepsy. The proportion of AED monotherapy was higher in patients with dementia (78.9%) and stroke (80.6%). The top three antiepileptic monotherapies were valproic acid (28.7%), levetiracetam (19.1%), and phenytoin (16.9%); however, oxcarbazepine (22.8%) was substituted for carbamazepine (3.9%) as monotherapy for patients aged 0-17 years. Among adult patients with epilepsy, the PDD/DDD ratio of each AED in monotherapy was less than 1.00. The mean PDD of each AED was higher in polytherapy than in monotherapy (p < 0.01), except for lacosamide. The mean PDDs of all evaluated AEDs in monotherapy were lower in elder adult patients than in younger adult patients, most of which reached statistical significance (p < 0.001).

CONCLUSIONS

In Taiwan, valproic acid was the most prescribed AED for prevalent patients with epilepsy. The mean PDDs of most AEDs were lower than the DDDs developed by the World Health Organization.

Therapeutic drug monitoring of newer generation antiseizure medications at the point of treatment failure

PURPOSE

The benefit of therapeutic drug monitoring (TDM) of newer generation antiseizure medications (ASM) has been little studied. A recent randomized study suggested that TDM at each medical visit did not bring a significant benefit, but the study did not investigate TDM in cases of treatment failure. Accordingly, we realized a post hoc analysis of this trial.

METHODS

We analyzed 282 TDMs in 136 patients. We compared TDM performed at visits after treatment failure versus without treatment failure, reporting the proportion of drug levels out of range and the prescriber's adherence to dosage recommendations according to measured drug levels.

RESULTS

There was no statistical difference in terms of proportion of out of range plasma drug levels (47% vs 50%, p = 0.7) or adherence of prescribers to the clinical pharmacologists' dosage recommendations (21% vs 30%, p = 0.6) between visits after treatment failure and visits without treatment failure, respectively. Knowledge of prior drug levels did not modify the results.

CONCLUSION

Systematic TDM at appointments following treatment failure showed similar results to TDM at visits without treatment failure. The prescribers' adherence with dosage recommendations was low in both cases. It is not clear whether better prescriber adherence would improve patient outcome. Furthermore, the ability to detect poor patient compliance is limited in a planned outpatient appointment. The study setting does not reflect on the general usefulness of TDM.

Patterns of anticonvulsant use and adverse drug events in older adults

PURPOSE

To examine indications for, duration of use, and rate of adverse drug events (ADE) attributable to anticonvulsant initiation, as adjudicated by expert review of electronic health records (EHR) of older adults.

METHODS

We identified a cohort of community dwelling Medicare beneficiaries with linked EHR (aged 65+, continuously enrolled with a large health system/until death between 2012 and 2014, n = 20 945) and drew a stratified EHR review sample (n = 1534). An expert reviewed all records to adjudicate anticonvulsant use, years of use, indication for use, and evidence of ADEs attributable to anticonvulsant initiation. After excluding patients with insufficient EHR data (n = 37; 2%), we reconstructed the cohort using inverse probability weights to resemble the original cohort of eligible beneficiaries (n = 20 380). Among incident users of a single anticonvulsant, we estimated the rate of ADEs and described the type and severity of ADEs.

RESULTS

Overall, 12% (n = 2469) of eligible beneficiaries used at least one anticonvulsant in the 2012 to 2014 period (4% [n = 757] incident users, 8% [n = 1712] prevalent users). Incident users were most frequently prescribed gabapentin (n = 461/757, 61%), benzodiazepines (n = 122/757, 16%), and levetiracetam (n = 74/757, 10%); the most common indication was pain relief (n = 214; 28%) followed by epilepsy (n = 53; 7%). Among incident users, the overall ADE rate was 10/100 person-years (95% CI 4-20/100 person-years), of which 29% (n = 28/97) were life threatening (eg, somnolence). Most ADEs among incident monotherapy users were nervous system related (68%, n = 66/97).

CONCLUSION

Many older adult community dwelling traditional Medicare beneficiaries had clinically significant ADEs likely attributable to the initiation of anticonvulsant therapy, which was begun for a range of indications.

Base de Datos para la Investigación Farmacoepidemiológica en Atención Primaria (BIFAP): A data resource for pharmacoepidemiology in Spain

PURPOSE

Base de Datos para la Investigación Farmacoepidemiológica en Atención Primaria (BIFAP) is a population based database administered by the AEMPS (Spanish Agency for Medicines) of longitudinal electronic medical records (EMR) of patients attended in primary care. Its main purpose is to serve as source of information for independent studies on drug safety and support of medicines regulation activities. This article aim is to describe the characteristics of BIFAP, how to access the database and a summary of its potential for research.

METHODS

Health problems are registered by primary care physicians as episodes of care and include socio-demographic data, results of diagnostic procedures, lifestyle data, general data, and interventions. A proportion of data on hospitalizations and specialist care are currently available through linkage with other data sources. EMRs of the Spanish healthcare system are provided by the regional administrations. Specific data extraction and standardization processes are performed.

RESULTS

BIFAP includes data from 12 million patients starting in 2001 and updated annually. Validation of drug and diagnosis definitions has been ascertained. Participation in international collaborative projects and a number of articles in peer reviewed journals reflect its contribution to the knowledge of the risks associated with medicines and drug utilization patterns.

CONCLUSIONS

BIFAP is a useful tool for generating scientific evidence on medicines related issues, helping regulatory decision making in Europe. The main strengths of BIFAP are related to large sample size, population-based, longitudinal nature and annual update of data. BIFAP shares common challenges with similar data sources including accurate and efficient identification of health outcomes and of treatment exposure.

Antiepileptic Drug Treatment Outcomes and Seizure-Related Injuries Among Adult Patients with Epilepsy in a Tertiary Care Hospital in Ethiopia

Objective

Anti-epileptic drugs (AEDs) are the primary therapeutic modalities for epilepsy management. However, one-third of epileptic patients continue to experience seizure even with appropriate AED use. Patients with epilepsy are at increased risk for seizure-related injury and they have higher incidences of home, street and work accidents. There is a paucity of data on AED use pattern and treatment outcomes among patients with epilepsy in the tertiary hospitals of Ethiopia. Therefore, the aim of this study was to assess AED use pattern, treatment outcome, and prevalence of seizure-related injury among patients with epilepsy in Tikur Anbessa specialized Hospital (TASH), Ethiopia.

Patients and Methods

An institution-based cross-sectional study was carried out on 291 patients with epilepsy attending the neurology clinic of TASH. A semi-structured questionnaire and data abstraction format were used to collect data through patient interview and medical chart review. Binary logistic regression was utilized to identify the associated factors of treatment outcome.

Results

About 172 (59%) of the patients were taking a single AED, in which phenobarbital, 195 (67%), and phenytoin, 97 (33.3%), were the most frequently prescribed AEDs as monotherapy and combination therapy. Headache, depressed mood and epigastric pain were frequently reported as adverse drug reactions. Seizure-related injury was reported among 78 (26.8%) patients and head injury 15 (5.2%), desntal injury 15 (5.2%), soft tissue injury 14 (4.8%) and burns 10 (3.4%) were the commonest. About two-thirds (191, 65.6%) of the study participants had uncontrolled seizure. Medication adherence and multiple AEDs were significantly associated with treatment outcome.

Conclusion

All the study participants were put on old generation AEDs with phenobarbital being the most frequently used. About two-thirds of the patients had uncontrolled seizure and seizure-related injury is still a serious concern among patients with epilepsy.

Impact of pre-exposure time bias in self-controlled case series when the event conditions the exposure: Hip/femur fracture and use of benzodiazepines as a case study

BACKGROUND

In self-controlled case series (SCCS), the event should not condition the probability of subsequent exposure. If this assumption is not met, an important bias could take place. The association of hip/femur fracture (HFF) and use of benzodiazepines (BDZ) has a bidirectional causal relationship and can serve as case study to investigate the impact of this methodological issue.

OBJECTIVES

To assess the magnitude of bias introduced in a SCCS when HFF conditions the posterior exposure to BDZ and explore ways to correct it.

METHODS

Four thousand four hundred fifty cases of HFF who had at least one BZD prescription were selected from the primary care health record database BIFAP. Exposure to BZD was divided into non-use, current, recent, and past use. Conditional Poisson regression was used to estimate incidence rate ratios (IRRs) of HFF among current vs non-use/past, adjusted for age. To investigate possible event-exposure dependence, a pre-exposure time of different lengths (15, 30, and 60 days) was excluded from the reference category to evaluate the IRR.

RESULTS

IRR of HHF for current use was 0.79 (0.72-0.86); removing 30 days, IRR was 1.43 (1.31-1.57). Removing 15 days, IRR was 1.29 (1.18-1.41), and removing 60 days, IRR was 1.56 (1.42-1.72). A pre-exposure period up to 182 days was necessary to remove such effect giving an IRR of 1.64 (1.48-1.81).

CONCLUSIONS

HFF remarkably conditioned the use of BDZs resulting in seriously biased IRRs when this association was studied through a SCCS design. The use of pre-exposure periods of different lengths helped to correct this error.

Trends in antiepileptic drug treatment and effectiveness in clinical practice in England from 2003 to 2016: a retrospective cohort study using electronic medical records

OBJECTIVE

To assess the evolution of antiepileptic drug (AED) treatment patterns and seizure outcomes in England from 2003 to 2016.

DESIGN, SETTING AND PARTICIPANTS

Retrospective cohort study of electronic medical records from Clinical Practice Research Datalink and National Health Service Digital Hospital Episode Statistics databases. Patients newly diagnosed with epilepsy were identified and followed until end of data availability. Three eras were defined starting 1 April 2003 (first National Institute for Health and Care Excellence (NICE) guideline); 1 September 2007 (Standard and New Antiepileptic Drugs publication); and 1 January 2012 (second NICE guideline).

OUTCOME MEASURES

Time from diagnosis to first AED; AED sequence; time from first AED to first 1-year remission period (no new AED attempts and no seizure-related healthcare events); time from first AED to refractoriness (third AED attempt regardless of reason); Kaplan-Meier analysis of time-to-event variables.

RESULTS

4388 patients were included (mean follow-up: 6.8, 4.2 and 1.7 years by era). 84.6% of adults (≥16 years), 75.5% of children (<16) and 89.1% of elderly subgroup (65+) received treatment within 1 year; rates were generally stable over time. Treatment trends included reduced use of carbamazepine (adult first line, era 1: 34.9%; era 3: 10.7%) and phenytoin, earlier line and increased use of levetiracetam (adult first line, era 1: 2.6%; era 3: 26.2%) and lamotrigine (particularly in adults and elderly subgroup), and a larger number of different AEDs used. Valproate use shifted somewhat to later lines. Rates of 1-year remission within 2 years of starting treatment increased in adults (era 1: 71.9%; era 3: 81.4%) and elderly (era 1: 76.1%; era 3: 81.7%). Overall, 55.5% of patients relapsed after achieving 1-year remission. Refractoriness rates remained stable over time (~26% of adults within 5 years).

CONCLUSION

Treatment trends often were not aligned with era-relevant guidance. However, our results suggest a slight improvement in epilepsy treatment outcomes over the 13-year period.

Factors influencing harmonized health data collection, sharing and linkage in Denmark and Switzerland: A systematic review

Introduction

The digitalization of medicine has led to a considerable growth of heterogeneous health datasets, which could improve healthcare research if integrated into the clinical life cycle. This process requires, amongst other things, the harmonization of these datasets, which is a prerequisite to improve their quality, re-usability and interoperability. However, there is a wide range of factors that either hinder or favor the harmonized collection, sharing and linkage of health data.

Objective

This systematic review aims to identify barriers and facilitators to health data harmonization—including data sharing and linkage—by a comparative analysis of studies from Denmark and Switzerland.

Methods

Publications from PubMed, Web of Science, EMBASE and CINAHL involving cross-institutional or cross-border collection, sharing or linkage of health data from Denmark or Switzerland were searched to identify the reported barriers and facilitators to data harmonization.

Results

Of the 345 projects included, 240 were single-country and 105 were multinational studies. Regarding national projects, a Swiss study reported on average more barriers and facilitators than a Danish study. Barriers and facilitators of a technical nature were most frequently reported.

Conclusion

This systematic review gathered evidence from Denmark and Switzerland on barriers and facilitators concerning data harmonization, sharing and linkage. Barriers and facilitators were strictly interrelated with the national context where projects were carried out. Structural changes, such as legislation implemented at the national level, were mirrored in the projects. This underlines the impact of national strategies in the field of health data. Our findings also suggest that more openness and clarity in the reporting of both barriers and facilitators to data harmonization constitute a key element to promote the successful management of new projects using health data and the implementation of proper policies in this field. Our study findings are thus meaningful beyond these two countries.

Intentional Drug Overdose Involving Pregabalin and Gabapentin: Findings from the National Self-Harm Registry Ireland, 2007-2015

INTRODUCTION

Intentional drug overdose (IDO) is a significant public health problem. Concerns about the misuse of gabapentinoids, i.e. pregabalin and gabapentin, including their consumption in IDO have grown in recent years. This paper examines the trends in the prevalence of gabapentinoids taken in IDO, the profile of individuals taking them, and associated overdose characteristics.

METHODS

Presentations to emergency departments involving IDO, recorded by the National Self-Harm Registry Ireland between 1 January 2007 and 31 December 2015 were examined. Data items included patient demographics, drug names, total tablet quantity consumed and alcohol involvement.

RESULTS

Gabapentinoids were involved in 2115 (2.9%) of the 72,391 IDOs recorded. Presentations involving a gabapentinoid increased proportionally from 0.5% in 2007 to 5.5% in 2015. The majority of IDOs involving a gabapentinoid were made by females (59.9%), with over one-third (37.2%) involving alcohol. Compared with IDOs involving other drugs, presentations with a gabapentinoid were made by persons who were older (median 37 vs. 32 years) and involved a significantly greater median quantity of tablets (30 vs. 21, p ≤ 0.001), with over one-quarter (27.4%) of these involving the ingestion of 50 tablets or more. Admission to hospital was significantly more common following IDOs with a gabapentinoid compared with those without (49.4% vs. 41.4%, p ≤ 0.001).

CONCLUSIONS

This study identified the increasing use of gabapentinoids in IDO, describing the profile and overdose characteristics of presentations. It is important for clinicians to exercise vigilance while prescribing gabapentinoids, including being aware of other medications that their patients may have access to. Our findings support the need for routine monitoring for signs of misuse among those prescribed gabapentinoids.

Declining trend in valproate use in Finland among females of childbearing age in 2012-2016 - a nationwide registry-based outpatient study

BACKGROUND AND PURPOSE

Documented teratogenic effects of valproate (VPA) prompted restrictions of its use in females of childbearing age in 2014. We investigated possible annual changes in the outpatient use of VPA in Finland during 2008-2016 with a special focus on women.

METHODS

We identified all outpatients with VPA purchases between 2008 and 2016 categorizing users due to epilepsy, bipolar disorder or miscellaneous indications. Temporal trends in the annual prevalence rates of VPA use were estimated using Poisson regression analyses.

RESULTS

Between 2012 and 2016, the prevalence of VPA use among women aged 15-44 years decreased by 19%, from 50/10 000 to 40/10 000 (prevalence rate ratio, 0.81; 95% confidence intervals, 0.77-0.91; P < 0.001). The use of VPA due to epilepsy decreased significantly in females aged 15-24 and 25-34 years and that due to bipolar disorders decreased significantly in females aged 25-34 and 35-44 years. The use of VPA in the miscellaneous indication group decreased by 32% after 2014 in females aged 15-44 years and, most strikingly, by 56% among those aged 15-25 years. In women with epilepsy, the use of VPA increased among those over the age of 44 years.

CONCLUSIONS

The rates of female VPA users with childbearing potential have decreased in all three major indication groups in Finland during recent years, especially after the European Medicines Agency restrictions were published in 2014. However, it still remains open to question as to whether the practice of VPA use follows current guidelines. A special concern is the relatively high prevalence of off-label use of VPA in fertile-aged females.

Observational multicentre study into the use of antiepileptic drugs in Spanish neurology consultations

INTRODUCTION

The study aims to quantify the types of antiepileptic drugs (AED) prescribed in neurology consultations.

MATERIAL AND METHOD

This descriptive, observational study included a sample of 559 patients older than 14 years, diagnosed with epilepsy, and receiving pharmacological treatment. Data were collected at outpatient consultations by 47 Spanish neurologists in May 2016. Epilepsy was defined based on the International League Against Epilepsy classification. According to the year of marketing, AEDs were categorised as classic (before 1990) or new (after 1990). We performed a descriptive analysis of qualitative and quantitative variables.

RESULTS

Female patients accounted for 54.6% of the sample. Mean age was 42.7 years; mean age of onset was 22.4. Regarding epilepsy type, 75.7% of patients experienced partial seizures, 51.5% were symptomatic,32.4% had refractory epilepsy, 35.6% had been seizure-free for the previous year, and 59.2% had associated comorbidities.A total of 1103 AED prescriptions were made; 64.6% of prescriptions were for new AEDs; 85.4% of patients received new AEDs. Patients received a mean of 2 AEDs (range, 1-5). A total of 59.6% of patients received polytherapy.The most frequently prescribed AEDs were levetiracetam (42.6%), valproic acid (25.4%), lamotrigine (19.5%), carbamazepine (17.9%), and lacosamide (17.5%). No AED was employed exclusively as monotherapy. The most frequently prescribed AEDs for generalised and partial seizures were valproic acid (48.2%) and levetiracetam (43.2%), respectively. Valproic acid was less frequently prescribed to female patients. Patients with refractory epilepsy or with associated comorbidities were more frequently prescribed a combination of new and classic AEDs (48.7% and 45.6%, respectively) than only one type of AED.

CONCLUSIONS

The majority of patients received new AEDs. The combination of classic and new AEDs was more frequently prescribed to patients with refractory epilepsy or with associated comorbidities.

Newer Antiepileptic Drugs in Status Epilepticus: Prescription Trends and Outcomes in Comparison with Traditional Agents

INTRODUCTION

Newer antiepileptic drugs (AEDs) are increasingly prescribed; however, relatively limited data are available regarding their use in status epilepticus (SE) and the impact on outcome.

OBJECTIVES

The aim of this study was to explore the evolution in prescription patterns of newer and traditional AEDs in this clinical setting, and their association with prognosis.

METHODS

We analyzed our prospective adult SE registry over a 10-year period (2007-2016) and assessed the yearly use of newer and traditional AEDs and their association with mortality, return to baseline conditions at discharge, and SE refractoriness, defined as treatment resistance to two AEDs, including benzodiazepines.

RESULTS

In 884 SE episodes, corresponding to 719 patients, the prescription of at least one newer AED increased from 0.38 per SE episode in 2007 to 1.24 per SE episode in 2016 (mostly due to the introduction of levetiracetam and lacosamide). Traditional AEDs (excluding benzodiazepines) decreased over time from 0.74 in 2007 to 0.41 in 2016, correlating with the decreasing use of phenytoin. The prescription of newer AEDs was independently associated with a lower chance of return to baseline conditions at discharge (odds ratio [OR] 0.58, 95% confidence interval [CI] 0.40-0.84) and a higher rate of SE refractoriness (OR 19.84, 95% CI 12.76-30.84), but not with changes in mortality (OR 1.08, 95% CI 0.58-2.00).

CONCLUSION

We observed a growing trend in the prescription of newer AEDs in SE over the last decade; however, our findings might suggest an associated increased risk of SE refractoriness and new disability at hospital discharge. Pending prospective, comparative studies, this may justify some caution in the routine use of newer AEDs in SE.

Changes in prevalence of psychotropic drug use and alcohol consumption among the elderly in Germany: results of two National Health Interview and Examination Surveys 1997-99 and 2008-11

BACKGROUND

Psychotropic drug use and alcohol consumption among older adults need to be monitored over time as their use or combined use bears risks of harms. Representative data on changes in prevalence, patterns and co-relates of substance use are lacking in Germany.

METHODS

Participants were older adults (60-79 years) from two German National Health Surveys: 1997-99 (GNHIES98, N = 1,606) and 2008-11 (DEGS1, N = 2,501). Included were drugs acting on the nervous system used during the last 7 days. Alcohol consumption was measured by frequency (daily drinking) and quantity (risky drinking: ≥20/10 g/day alcohol for men/women). Changes in prevalence adjusted for potential socio-economic and health-related confounders were calculated by logistic regression models approximated by the SAS LSMEANS statement.

RESULTS

The prevalence of overall psychotropic drug use (20.5% vs. 21.4%) remained constant between the two surveys. Significant changes were observed in the use of some psychotropics (all GNHIES98 vs. DEGS1): Synthetic antidepressants (3.9% vs. 6.9%), St. John's wort (2.9% vs. 1.1%), benzodiazepines (3.7% vs. 2.5%), benzodiazepine related drugs (0.2% vs. 0.8%), narcotic analgesics (3.0% vs. 4.1%), anti-dementia drugs (2.2% vs. 4.2%) and anti-epileptics (1.0% vs. 2.3%). Significant changes were also observed in long-term use of synthetic anti-depressants (3.2% vs. 5.9%), St. John's wort (2.0% vs. 0.6%) and opioid analgesics (1.0% vs. 2.2%). Further, we found significant changes in benzodiazepines use (3.3% vs. 1.4%) among men, opioids use (2.9% vs. 7.3%) among people with a lower social status, and overall psychotropics (26.8% vs. 32.5%) as well as opioids use (4.4% vs. 8.1%) among those with a worse health status. Moderate alcohol consumption increased significantly (58.0% vs. 66.9%). Risky drinking remained unchanged (16.6% vs. 17.0%). In spite of significant increases in daily alcohol drinking (13.2% vs. 18.4%) psychotropic drug use combined with daily drinking remained unchanged (1.8% vs. 2.7%).

CONCLUSIONS

Although prevalence of overall psychotropic drug use remained stable, changes in the use of some psychotropic drug groups and alcohol consumption patterns have been observed. Further studies are required to investigate resulting health consequences and public health relevance of those outcomes.

The IMI PROTECT project: purpose, organizational structure, and procedures

The Pharmacoepidemiological Research on Outcomes of Therapeutics by a European ConsorTium (PROTECT) initiative was a collaborative European project that sought to address limitations of current methods in the field of pharmacoepidemiology and pharmacovigilance. Initiated in 2009 and ending in 2015, PROTECT was part of the Innovative Medicines Initiative, a joint undertaking by the European Union and pharmaceutical industry. Thirty-five partners including academics, regulators, small and medium enterprises, and European Federation of Pharmaceuticals Industries and Associations companies contributed to PROTECT. Two work packages within PROTECT implemented research examining the extent to which differences in the study design, methodology, and choice of data source can contribute to producing discrepant results from observational studies on drug safety. To evaluate the effect of these differences, the project applied different designs and analytic methodology for six drug-adverse event pairs across several electronic healthcare databases and registries. This papers introduces the organizational structure and procedures of PROTECT, including how drug-adverse event and data sources were selected, study design and analyses documents were developed, and results managed centrally.

Impact of varying outcomes and definitions of suicidality on the associations of antiepileptic drugs and suicidality: comparisons from UK Clinical Practice Research Datalink (CPRD) and Danish national registries (DNR)

PURPOSE

The purpose of this study is to quantify the impact of the different outcomes and definitions of suicidality on the association between antiepileptic drugs (AEDs) and suicidality.

METHODS

Retrospective cohort studies of selected AEDs (carbamazepine, gabapentin, lamotrigine, phenytoin, pregabalin, topiramate and valproate) using data from UK Clinical Practice Research Datalink (CPRD) alone and linked to UK Hospital Episode Statistics (HES) and UK Office of National Statistics (ONS), and from Danish national registries (DNR). Follow-up started at initiation of one of the study AEDs, divided into exposure periods, a maximum 90-day post-exposure period, and the reference period starting the day after the 90-day post-exposure period ended. Primary outcomes were completed suicide (SUI)/suicide attempt (SA) for CPRD and SUI/deliberate self-harm (DSH) for DNR. We applied adjusted Cox regression analyses and sensitivity analyses with varying outcome definitions.

RESULTS

We analyzed 84,524 AED users from CPRD-HES-ONS (1188 SUI/SA; 96 SUI) and 258,180 users from DNR (7561 SUI/DSH; 781 SUI). The adjusted hazard ratios (HRs) on SUI/SA ranged between 1.3 (95% confidence interval (CI): 0.84-2.00) for lamotrigine and 2.7 (1.24-5.81) for phenytoin in CPRD-HES-ONS, and between 0.9 (0.78-1.00) for valproate and 1.8 (1.10-3.07) for phenytoin on SUI/DSH in DNR. HRs for the primary outcomes varied consistently across exposure periods and data sources. HRs for SUI were in general lower, more stable and similar for periods of exposure and the 90-day post-exposure period.

CONCLUSION

Applying different outcomes and definitions of suicidality had an impact on the relative risks of suicidality associated with the investigated AEDs with results for SUI being most consistent and reliable.

Utilization of antiepileptic drugs in Israel

PURPOSE

The aim of the study was to identify trends in utilization of antiepileptic drugs (AEDs) over time in a nation-wide population in Israel.

METHODS

Data on AED utilization (for all indications) for the period 2010-2014 were obtained from pharmaceutical companies that distribute AEDs in Israel. Prevalence of AED utilization was reported as defined daily doses (DDD)/1000 inhabitants/day.

RESULTS

The utilization of most AEDs included in our analysis remained stable over the study period. The greatest increases in utilization of drugs established in Israel were observed for lamotrigine (33%), oxcarbazepine (31%), and primidone (18%). Decreases in use were recorded for carbamazepine (18%) and phenobarbital (15%). Use of older AEDs appeared to be relatively high, compared with the use of newer AEDs.

CONCLUSIONS

During the study period of 2010-2014, conventional AEDs remained a main treatment choice in Israel, in certain cases in contrast to current recommendations and guidelines, for reasons yet to be revealed in further research.

Changes in utilisation of antiepileptic drugs in epilepsy and non-epilepsy disorders-a pharmacoepidemiological study and clinical implications

PURPOSE

The purpose of this study was to investigate changes in utilisation of antiepileptic drugs (AEDs) in epilepsy and non-epilepsy disorders in Norway and furthermore to study the retention rates of the most commonly used AEDs in these indications in long-term use.

METHODS

The data consisted of all prescriptions of AEDs from Norwegian pharmacies in the Norwegian Prescription Database (NorPD) (2004-2012). Variables included anonymous data regarding age, gender, diagnosis specific reimbursement codes and utilisation of AEDs.

RESULTS

In recent years (2008-2012), the utilisation of AEDs in non-epilepsy disorders accounted for 45-53 % of the total use. In epilepsy, the most commonly used AED was lamotrigine, followed by levetiracetam, carbamazepine and valproate. Lamotrigine was also the predominant AED used in psychiatry, while pregabalin and gabapentin were mostly used in neuropathic pain. In migraine, topiramate predominated but accounted for <1 % of the total utilisation of AEDs. The majority of prescriptions were by general practitioners and only 20 % by specialists. Regardless of indication, newer AEDs had higher retention rates (34-48 %) and were used for a longer period before discontinuation.

CONCLUSIONS

The use of AEDs in non-epilepsy disorders is increasing and accounted for 53 % in 2012. Newer AEDs were predominantly used and demonstrated higher retention rates than older AEDs in all indications. This nationwide study demonstrates an increased exposure to AEDs in new patient groups, and details in prescription patterns and clinical and safety considerations should be closely monitored. This contributes to long-term post-marketing data of AED and accordingly improved pharmacovigilance.

The Risk of Specific Congenital Anomalies in Relation to Newer Antiepileptic Drugs: A Literature Review

BACKGROUND

More information is needed about possible associations between the newer anti-epileptic drugs (AEDs) in the first trimester of pregnancy and specific congenital anomalies of the fetus.

OBJECTIVES

We performed a literature review to find signals for potential associations between newer AEDs (lamotrigine, topiramate, levetiracetam, gabapentin, oxcarbazepine, eslicarbazepine, felbamate, lacosamide, pregabalin, retigabine, rufinamide, stiripentol, tiagabine, vigabatrin, and zonisamide) and specific congenital anomalies.

METHODS

We searched PubMed and EMBASE to find observational studies with pregnancies exposed to newer AEDs and detailed information on congenital anomalies. The congenital anomalies in the studies were classified according to the congenital anomaly subgroups of European Surveillance of Congenital Anomalies (EUROCAT). We compared the prevalence of specific congenital anomalies in fetuses exposed to individual AEDs in the combined studies with that of the general population in a reference database. A significantly higher prevalence based on three or more fetuses with anomalies was considered a signal.

RESULTS

Topiramate showed a higher rate of congenital anomalies than the other newer AEDs. Four signals were found. The signals for associations between topiramate and cleft lip with/without cleft palate and hypospadias were considered strong. Associations between lamotrigine and anencephaly and transposition of great vessels were found within one study and were not supported by other studies. No signals were found for the other newer AEDs, or the information was too limited to provide such a signal.

CONCLUSION

In terms of associations between monotherapy with a newer AED in the first trimester of pregnancy and a specific congenital anomaly, the signals for topiramate and cleft lip with/without cleft palate and hypospadias should be investigated further.

Electronic Health Data for Postmarket Surveillance: A Vision Not Realized

What has been learned about electronic health data as a primary data source for regulatory decisions regarding the harms of drugs? Observational studies with electronic health data for postmarket risk assessment can now be conducted in Europe and the US in patient populations numbering in the tens of millions compared with a few hundred patients in a typical clinical trial. With standard protocols, results can be obtained in a few months; however, extensive research published by scores of investigators has illuminated the many obstacles that prevent obtaining robust, reproducible results that are reliable enough to be a primary source for drug safety decisions involving the health and safety of millions of patients. The most widely used terminology for coding patient interactions with medical providers for payment has proved ill-suited to identifying the adverse effects of drugs. Directly conflicting results were reported in otherwise similar patient health databases, even using identical event definitions and research methods. Evaluation of some accepted statistical methods revealed systematic bias, while others appeared to be unreliable. When electronic health data studies detected no drug risk, there were no robust and accepted standards to judge whether the drug was unlikely to cause the adverse effect or whether the study was incapable of detecting it. Substantial investment and careful thinking is needed to improve the reliability of risk assessments based on electronic health data, and current limitations need to be fully understood.

Indications of newer and older anti-epileptic drug use: findings from a southern Italian general practice setting from 2005-2011

AIMS

The aim of the study was to analyze the prescribing pattern of both newer and older AEDs.

METHODS

A population of almost 150 000 individuals registered with 123 general practitioners was included in this study. Patients who received at least one AED prescription over 2005-2011 were identified. The 1 year prevalence and cumulative incidence of AED use, by drug class and individual drug, were calculated over the study period. Potential predictors of starting therapy with newer AEDs were also investigated.

RESULTS

The prevalence of use per 1000 inhabitants of older AEDs increased from 10.7 (95% CI10.1, 11.2) in 2005 to 13.0 (95% CI12.4, 13.6) in 2011, while the incidence remained stable. Newer AED incidence decreased from 9.4 (95% CI 8.9, 9.9) in 2005 to 7.0 (95% CI 6.6, 7.5) in 2011, with a peak of 15.5 (95% CI 14.8, 16.1) in 2006. Phenobarbital and valproic acid were the most commonly prescribed AEDs as starting therapy for epilepsy. Gabapentin and pregabalin accounted for most new pain-related prescriptions, while valproic acid and lamotrigine were increasingly used for mood disorders. Female gender (OR 1.36, 95% CI 1.20, 1.53), age ranging between 45-54 years (OR 1.39, 95% CI 1.16, 1.66) and pain as an indication (OR 16.7, 95% CI, 13.1, 21.2) were associated with newer AEDs starting therapy.

CONCLUSIONS

Older AEDs were mainly used for epileptic and mood disorders, while newer drugs were preferred for neuropathic pain. Gender, age, indication of use and year of starting therapy influenced the choice of AED type. The decrease of newer AED use during 2007 is probably related to the restricted reimbursement criteria for gabapentin and pregabalin.

Availability of antiepileptic drugs across Europe

Europe consists of 53 countries with widely different economic conditions and different political, educational, and health care systems. This study was aimed at determining the availability of antiepileptic drugs (AEDs) across Europe. An electronic questionnaire was submitted to all 43 European chapters of the International League Against Epilepsy (ILAE). Outcome measures were availability of older, newer, and newest AEDs, generic products, indications, reimbursement rules, and reasons for lack of availability of AEDs. Countries were divided according to economic status as defined by the World Bank. Thirty-four chapters (79%) provided data. There were large differences in AED availability across countries, especially between high-income countries and the other countries. The newest AEDs were not available in any of the 12 non-high-income countries. Availability was higher in countries with public reimbursement systems. Reimbursement policies ranged from full reimbursement for all AEDs to complete lack of reimbursement. Main hurdles for poor access to AEDs included lack of regulatory approval, high prices and reimbursement restrictions. The availability of AEDs differs across European countries, with many hurdles hampering access to epilepsy medicines, particularly to new medications. These findings raise major concerns on the quality of epilepsy care in many countries.

Changing incidence of hyperammonemia in Japan from 2006 to 2013: expansion of new antiepileptic drugs reduces the risk of hyperammonemia

PURPOSE

The purpose of the present study was to examine the relationship between the incidence of hyperammonemia and changes in the prescribing of concomitant antiepileptic drugs (AEDs) in patients receiving valproic acid.

METHODS

We evaluated 40,363 plasma samples from 6009 epilepsy patients obtained from 2006 to 2013. Hyperammonemia was defined as a plasma ammonia level exceeding 100 μg/dL.

RESULTS

In 2006, 32.6 % of the plasma samples were from patients with concomitant use of phenytoin but this decreased to 16.0 % in 2013. Lamotrigine and levetiracetam were approved in 2008 and 2010, respectively, and were prescribed for patients who provided 27.8 and 14.9 % of the plasma samples in 2013. The incidence rate of hyperammonemia (per 100 person years) decreased markedly from 40.8 (95 % confidence interval (CI), 37.7-43.9) in 2006 to 14.2 (95 % CI, 12.5-15.9) in 2013. In any year reviewed, concomitant use of phenytoin, phenobarbital, carbamazepine, or carbonic anhydrase inhibitors was a risk factor for hyperammonemia. Among enzyme-inducing AEDs, concomitant use of phenytoin was associated with the highest risk of hyperammonemia.

CONCLUSION

Drug interactions caused by enzyme-inducing AEDs, especially phenytoin, are closely related to the development of hyperammonemia. This study demonstrated that introduction of new AEDs changed the co-prescribing pattern in patients receiving valproic acid, resulting in a marked decrease of hyperammonemia. Although their higher cost may be problematic, new AEDs are beneficial for reducing the risk of drug interactions.