Comparison of Drug Utilization Patterns in Observational Data: Antiepileptic Drugs in Pediatric Patients

Long-term safety and efficacy of adjunctive brivaracetam in pediatric patients with epilepsy: An open-label, follow-up trial

OBJECTIVE

This study was undertaken to evaluate the long-term safety, tolerability, and efficacy of adjunctive brivaracetam (BRV) treatment in pediatric patients with epilepsy.

METHODS

A phase 3, open-label, multicenter, long-term follow-up trial (N01266; NCT01364597) was conducted on patients (aged 1 month to <17 years at core trial entry; direct enrollers aged 4 to <17 years) treated with BRV. Outcomes included treatment-emergent adverse events (TEAEs), behavior assessments (Achenbach Child Behavior Checklist [CBCL], Behavior Rating Inventory of Executive Function [BRIEF]/BRIEF-Preschool version [BRIEF-P]), and efficacy outcomes (percent change in focal seizure frequency, 50% responder rate for all seizure types for patient subgroups <2 years and ≥2 years of age using daily record card data).

RESULTS

Of 257 patients with ≥1 dose of BRV (141 [54.9%] male; mean age = 8.0 years [SD = 4.5]), 36 patients were <2 years of age, and 72.0% of patients had a history of focal seizures. Mean BRV exposure was 3.2 patient-years. At least one TEAE occurred in 93.4% patients, and 32.3% had serious TEAEs. Seven patients died during the trial; no deaths were considered treatment-related. Patients ≥2 years of age had a median decrease in 28-day adjusted focal seizure frequency of 62.9%, and 50.9% had a ≥50% response in all seizures. Patients <2 years of age had a median decrease in 28-day adjusted focal seizure frequency of 96.9%, and 68.2% had a ≥50% response in all seizures. Kaplan-Meier estimated treatment retention was 72.7%, 64.5%, 57.8%, 53.3%, 50.1%, and 44.8% at 1, 2, 3, 4, 5, and 6 years, respectively. Mean changes (baseline to last evaluation) for all Achenbach CBCL and BRIEF-P/BRIEF subscale scores were negative, reflecting stability/slight improvement.

SIGNIFICANCE

Long-term adjunctive BRV treatment was generally well tolerated and efficacious in reducing seizure frequency, and had high retention rates, with generally stable cognitive/behavioral scores in pediatric patients with epilepsy.

Utilization of Antiseizure Medications in Women of Childbearing Age With Epilepsy and Nonepilepsy Indications: A Retrospective Cohort Study

BACKGROUND AND OBJECTIVES

Antiseizure medications (ASMs) are among the most commonly prescribed teratogenic drugs in women of childbearing age. Limited data exist on utilization patterns across different indications for therapy and for the newer-generation ASMs in this population. Thus, we assessed the pattern of ASM use in women of childbearing age with epilepsy and nonepilepsy indications (pain and psychiatric disorders).

METHODS

We conducted a retrospective analysis of deidentified administrative data submitted to the Optum Clinformatics database. Eligible participants included women aged 12-50 years who filled ASMs between year 2011 and 2017. Participants were followed from date of index prescription filled to study end or insurance disenrollment, whichever came first. For the overall cohort and potential therapy indications, we assessed the type and frequency of ASMs filled; proportion of participants on monotherapy, polytherapy, or treatment switching; and duration of continuous use. Trends were characterized using annual percent change from study start to study end.

RESULTS

Our analysis included 465,131 participants who filled 603,916 distinct ASM prescriptions. At baseline, most of the participants had chronic pain (51.0%) and psychiatric disorders (32.7%), with epilepsy the least common (0.9%). The most frequently dispensed were diazepam (24.3%), lorazepam (20.1%), gabapentin (17.4%), clonazepam (12.7%), topiramate (11.3%), and lamotrigine (4.6%). Significant linear increase in trends were observed with gabapentin (annual percent change [95% CI]: 8.4 [7.3-9.4]; p < 0.001) and levetiracetam (3.4 [0.7-6.2]; p = 0.022) and decreasing trends for diazepam (-3.5 [-2.4 to 4.5]; p < 0.001) and clonazepam (-3.4 [-2.3 to 4.5]; p = 0.001). No significant change in trend was observed with valproate (-0.4 [-2.7 to 1.9]; p = 0.651), while nonlinear changes in trends were observed with lorazepam, topiramate, lamotrigine, and pregabalin.

DISCUSSION

Decreasing trends were observed with older ASMs in the overall cohort and across the potential indications for therapy. Conversely, increasing trends were seen with the newer ASMs. Considering the risk of teratogenicity associated with the newer medications largely unknown, counseling and education in addition to a careful consideration of the benefits vs potential risks should remain pivotal when prescribing ASMs for women of childbearing age.

Analysis of the prescription pattern of psychotropics in an outpatient department of a general hospital psychiatry unit

BACKGROUND

World Health Organization has prescribed drug use indicators for evaluating rational prescribing. Very few studies have been conducted on rational prescriptions for psychotropic drugs; hence, this study was undertaken at a tertiary care center of North India.

METHODS

After obtaining approval of the Institutional Ethics Committee, all prescriptions deposited with the dispensary of the psychiatry department of the hospital between 01 October 2017 and 31 December 2017 were included in the study. The prescriptions were analyzed for drug use indicators, namely the average number of drugs per encounter, percentage of prescriptions with generic name, percentage of prescriptions from the essential drug list, percentage of prescriptions with antibiotics, and percentage of prescriptions with an injection. In addition, the prescriptions were analyzed for patterns of psychotropics prescribed.

RESULTS

A total of 3770 prescriptions were analyzed. On an average, 2.35 medicines were prescribed per prescription. Injectable comprised 2.39% of prescriptions and fixed drug combinations were 0.16% of the total. Of all prescriptions, 91.3% were by generic name, while 55.02% of prescriptions were from the essential drug list. Polypharmacy constituted 4.53% of prescriptions. Risperidone, escitalopram, sodium valproate, and clonazepam were the most commonly prescribed drugs.

CONCLUSION

While we fared well with respect to the percentage of prescriptions with injections and those with an antibiotic, we have not been able to achieve the prescribed standards in prescription with generic names, number of drugs per prescription, and prescriptions from the essential drug list. The study emphasizes that there is scope for improvement.

Safety and tolerability profile of new antiepileptic drug treatment in children with epilepsy

INTRODUCTION

Treatment of pediatric epilepsy requires a careful evaluation of the safety and tolerability profile of antiepileptic drugs (AEDs) to avoid or minimize as much as possible adverse events (AEs) on various organs, hematological parameters, and growth, pubertal, motor, cognitive and behavioral development.

AREAS COVERED

Treatment-emergent AEs (TEAEs) reported in the literature 2000-2018 regarding second- and third-generation AEDs used in the pediatric age, with exclusion of the neonatal period that exhibits specific peculiarities, have been described on the basis of their frequency, severity/tolerability, and particular association with a given AED.

EXPERT OPINION

Somnolence/sedation and behavioral changes, like irritability and nervousness, are among the most commonly observed TEAEs associated with almost all AEDs. Lamotrigine, Gabapentin, Oxcarbazepine, and Levetiracetam appear to be the best-tolerated AEDs with a ≤2% withdrawal rate, while Tiagabine and Everolimus are discontinued in up to >20% of the patients because of intolerable TEAEs. For some AEDs, literature data are scanty to draw a high-level evidence on their safety and tolerability profile. The reasons are: insufficient population size, short duration of treatments, or lack of controlled trials. A future goal is that of identifying clearer, easier, and more homogeneous methodological strategies to facilitate AED testing in pediatric populations.

Epilepsy Disorders and Treatment Modalities

Epilepsy disorders are the most common treatable neurological disorders in childhood. Diagnosis and treatment of these disorders has improved over time. Children with epilepsy/seizure disorder are more likely to have or develop mental health and developmental comorbidities such as depression, anxiety, attention deficit hyperactivity disorder, learning disabilities, and developmental delay compared to children without epilepsy/seizure disorder. If seizures can be controlled, quality of life will improve. This article will review the current medical treatment for seizures and epilepsy, including medications, vagus nerve stimulation (VNS), dietary modifications, and surgical intervention.

Oxcarbazepine oral suspension in young pediatric patients with partial seizures and/or generalized tonic-clonic seizures in routine clinical practice in China: a prospective observational study

BACKGROUND

This study aimed to assess efficacy and safety of oxcarbazepine (OXC) oral suspension in pediatric patients aged 2-5 years with partial seizures (PS) and/or generalized tonic-clonic seizures (GTCS) in real-world clinical practice in China.

METHODS

This 26-week, prospective, single-arm, multicenter, observational study recruited pediatric patients aged 2-5 years with PS or GTCS suitable for OXC oral suspension treatment based on physicians' judgments from 11 medical centers in China. Enrolled subjects started OXC oral suspension treatment as monotherapy or in combination with other antiepileptic drugs. Primary efficacy outcome was the percentage of pediatric subjects achieving ≥ 50% seizure frequency reduction at the end of the 26-week treatment. Secondary efficacy-related parameters and safety parameters such as adverse events (AEs) and serious AEs (SAEs) were also monitored during the 26-week treatment period.

RESULTS

Six hundred and six pediatric patients were enrolled and 531 (87.6%) completed the study. After 26 weeks of treatment, 93.3% subjects achieved ≥ 50% seizure frequency reduction, and 81.8% achieved 100% seizure frequency reduction compared to baseline. Among different seizure types, OXC was effective in all subjects with simple PS and in > 90% of subject with other type of seizure present in the study. AEs were observed in 49 (8.1%) subjects. Only three subjects experienced SAE. Rash (n = 18, 2.97%) was the most common AE. Only 17 subjects discontinued due to AEs.

CONCLUSION

This study, reporting the real-world data, further confirms the efficacy and good safety profile of OXC oral suspension in Chinese pediatric patients aged 2-5 years with PS and/or GTCS.

[PRRT2 mutation and infantile convulsions]

New genetic techniques have made it possible to better understand the implications of the PRRT2 gene (proline rich transmembrane protein 2) in various neurological disorders. Mutations within this gene are responsible for kinesigenic paroxysmal dyskinesias (PKD) as well as for benign familial infantile epilepsy (BFIE), a disease associating infantile convulsions and choreoathetosis (ICCA), a form of familial hemiplegic migraine (FHM type 4), paroxysmal benign torticollis of childhood, and episodic ataxia. We describe the case of an infant, carrying a mutation of the PRRT2 gene, with a classical presentation. Through her progression over time, we raise the question of systematic use of anti-epileptic drugs.

Anti-epileptic drug utilisation in paediatrics: a systematic review

OBJECTIVES

This study aims to determine global anti-epileptic drug (AED) utilisation prevalence and describe utilisation trends in different countries.

METHODS

Databases Embase (1980-May 2017), Medline (1946-May 2017) and PubMed were searched for original research on AED utilisation. All paediatric national or regional database studies and surveys were included.

RESULTS

Twenty-one studies were identified. Five were excluded from the analysis as the data were collected before 2005, leaving 16 studies. Monotherapy regimen varied between 58% and 94% in different countries. In several of the studies, sodium valproate was the most frequently prescribed AED. However, there is a trend towards increasing utilisation of new-generation AEDs, particularly levetiracetam, in some countries.

CONCLUSION

Monotherapy was used in 58%-94%of patients. There is increasing utilisation of the new-generation AEDs, in particular lamotrigine, levetiracetam and topiramate. Old-generation AEDs are still used in the majority of patients. There is a need for up-to-date studies to determine the prevalence of AEDs in children.

Antiepileptic drug discontinuation by people with epilepsy in the general population

OBJECTIVE

Rate, reasons, and predictors of antiepileptic drug (AED) discontinuation were investigated in a well-defined cohort of people with epilepsy to verify efficacy and tolerability of treatment up to 20 years from treatment initiation.

METHODS

The history of AED usage in children and adults with epilepsy registered with 123 family physicians in an area of Northern Italy between 2000 and 2008 was recorded. Cumulative probabilities of AED withdrawal for specific reasons were estimated using cumulative incidence functions. The probabilities of withdrawing for terminal remission, and of achieving sustained remission while still on treatment, were also evaluated. The roles of sex, age at diagnosis, seizure types, duration at diagnosis, and syndrome were assessed with hazard ratios and 95% confidence intervals.

RESULTS

Seven hundred thirty-one of 747 individuals were treated with one or more AEDs during the disease course. The three commonest drugs were valproate, carbamazepine, and phenobarbital. Reported reasons for AED withdrawal were, in decreasing order, terminal remission, ineffectiveness, and adverse events. The probability of withdrawing the first AED for terminal remission was 1.0% at 1 year and increased to 20.0% at 20 years. Corresponding rates were 2.9% and 12.6% for ineffectiveness and 0.5% and 3.3% for adverse events. Reasons for withdrawal varied with individuals' age, sex, disease characteristics, and drugs.

SIGNIFICANCE

The initial AED given was retained in the majority of cases. Terminal remission, lack of efficacy, and adverse effects were, in decreasing order, the commonest reasons for AED discontinuation. Withdrawal could be predicted by age at diagnosis, sex, and clinical characteristics and varies among drugs.

Properties of healthcare teaming networks as a function of network construction algorithms

Network models of healthcare systems can be used to examine how providers collaborate, communicate, refer patients to each other, and to map how patients traverse the network of providers. Most healthcare service network models have been constructed from patient claims data, using billing claims to link a patient with a specific provider in time. The data sets can be quite large (106-108 individual claims per year), making standard methods for network construction computationally challenging and thus requiring the use of alternate construction algorithms. While these alternate methods have seen increasing use in generating healthcare networks, there is little to no literature comparing the differences in the structural properties of the generated networks, which as we demonstrate, can be dramatically different. To address this issue, we compared the properties of healthcare networks constructed using different algorithms from 2013 Medicare Part B outpatient claims data. Three different algorithms were compared: binning, sliding frame, and trace-route. Unipartite networks linking either providers or healthcare organizations by shared patients were built using each method. We find that each algorithm produced networks with substantially different topological properties, as reflected by numbers of edges, network density, assortativity, clustering coefficients and other structural measures. Provider networks adhered to a power law, while organization networks were best fit by a power law with exponential cutoff. Censoring networks to exclude edges with less than 11 shared patients, a common de-identification practice for healthcare network data, markedly reduced edge numbers and network density, and greatly altered measures of vertex prominence such as the betweenness centrality. Data analysis identified patterns in the distance patients travel between network providers, and a striking set of teaming relationships between providers in the Northeast United States and Florida, likely due to seasonal residence patterns of Medicare beneficiaries. We conclude that the choice of network construction algorithm is critical for healthcare network analysis, and discuss the implications of our findings for selecting the algorithm best suited to the type of analysis to be performed.

Causal inference as an emerging statistical approach in neurology: an example for epilepsy in the elderly

The elderly population faces an increasing number of cases of chronic neurological conditions, such as epilepsy and Alzheimer's disease. Because the elderly with epilepsy are commonly excluded from randomized controlled clinical trials, there are few rigorous studies to guide clinical practice. When the elderly are eligible for trials, they either rarely participate or frequently have poor adherence to therapy, thus limiting both generalizability and validity. In contrast, large observational data sets are increasingly available, but are susceptible to bias when using common analytic approaches. Recent developments in causal inference-analytic approaches also introduce the possibility of emulating randomized controlled trials to yield valid estimates. We provide a practical example of the application of the principles of causal inference to a large observational data set of patients with epilepsy. This review also provides a framework for comparative-effectiveness research in chronic neurological conditions.

Duration of use of oral cannabis extract in a cohort of pediatric epilepsy patients

OBJECTIVE

Oral cannabis extracts (OCEs) are being used in the treatment of epilepsy with increasing rates in the United States following product legalization; however, no studies demonstrate clear efficacy. We evaluated the duration of use of OCEs as a measure of perceived benefit in a cohort of patients with pediatric epilepsy.

METHODS

Retrospective chart review was performed of children and adolescents who were given OCEs for treatment of epilepsy.

RESULTS

Of the 119 patients included in the analysis, 71% terminated use of their OCE product during the study period. The average length of use of OCE was 11.7 months (range 0.3-57 months). Perceived seizure benefit was the only factor associated with longer duration of treatment with OCE (p < 0.01). Relocation to Colorado was associated with perceived benefit of OCEs for seizures (65% vs. 38%, p = 0.01), but was not independently associated with longer OCE use. Factors associated with shorter use included adverse effects (p = 0.03) and a diagnosis of Dravet syndrome (p = 0.02). Twenty-four percent of patients were considered OCE responders, which was defined by a parent's report of a > 50% reduction in seizures while on this therapy. Adverse events (AEs) were reported in 19% of patients, with the most common side effects being somnolence and worsening of seizures.

SIGNIFICANCE

Parental report of OCE use in refractory pediatric epilepsy suggests that some families perceive benefit from this therapy; however, discontinuation of these products is common. Duration appears to be affected by logical factors, such as perceived benefit and side effect profile. Surprisingly, families of patients with Dravet syndrome terminated use of OCEs more quickly than patients with other epilepsy syndromes. Results from this study highlight the need for rigorous clinical studies to characterize the efficacy and safety of OCEs, which can inform discussions with patients and families.

Trends in Antiepileptic Drug Prescriptions for Childhood Epilepsy at a Tertiary Children's Hospital in Korea, 2001-2012

OBJECTIVES

Longitudinal prescription patterns of antiepileptic drugs (AEDs) have not been described to date in Korea. Here we aimed to describe AED prescribing trends over a 12-year period and assess age differences in AED prescribing patterns in a pediatric epilepsy population.

METHODS

We retrieved and analyzed all AED prescribing and dispensing data in 2001-2012 in patients aged 0-18 years with an established diagnosis of epilepsy at the largest tertiary children's hospital in Korea. AEDs included for analysis were classified as older (i.e., carbamazepine, ethosuximide, phenobarbital, phenytoin, and valproic acid) and newer (i.e., gabapentin, lamotrigine, levetiracetam, oxcarbazepine, pregabalin, topiramate, vigabatrin, zonisamide, lacosamide, and rufinamide) on the basis of market availability before versus after 1991.

RESULTS

A total of 5593 patients with epilepsy were prescribed an AED during the 12-year period. The proportion of newer AED prescriptions was 52.6 % in 2001 and continuously increased to 74.3 % in 2012. Oxcarbazepine was most widely used, followed by valproic acid. While carbamazepine and vigabatrin use progressively decreased over the 12-year period, those of lamotrigine and topiramate rapidly increased. Age differences in prescribing patterns were observed. Polytherapy was observed in 49.7 % of the total population, while 83.9 % of new users were prescribed monotherapy.

CONCLUSION

This study provided updated information on AED prescription trends for childhood epilepsy. We found a progressive increase in the use of newer AEDs. However, valproic acid, the only prevalent older AED, continued to be widely prescribed. A high rate of polytherapy among the prescriptions overall raises some safety concerns.