Utilization of antiepileptic drugs in Israel

Prescribed antiseizure medication doses and their relation to defined daily doses for achieving seizure freedom in newly diagnosed patients with epilepsy

OBJECTIVES

To investigate the antiseizure medication (ASM) doses required to achieve seizure freedom and their correlation with the World Health Organization's defined daily doses (DDDs) in patients aged 16 years or older with newly diagnosed epilepsy.

METHODS

The study included 459 patients with a validated diagnosis of new-onset epilepsy. Patient records were retrospectively analyzed to determine the ASM doses in patients with or without seizure freedom during follow-up. The DDD of the relevant ASM was then retrieved.

RESULTS

The seizure-freedom rate with first and subsequent ASMs was 88% (404/459 patients) during the follow-up. The mean prescribed doses (PDDs) and PDD/DDD ratio of the most commonly used ASMs, ie, oxcarbazepine (OXC), carbamazepine (CBZ), and valproic acid (VPA), differed significantly between seizure-free and non-seizure-free status (992 mg and 0.99 vs 1132 mg and 1.13; 547 mg and 0.55 vs 659 mg and 0.66; and 953 mg and 0.64 vs 1260 mg and 0.84, respectively). The effect of the OXC dose as the first failed ASM on the possibility of achieving seizure freedom was significant (Fisher's exact test, p = 0.002). Thirty-four of 43 patients (79%) in which an OXC dose of ≤900 mg failed became seizure-free, as compared with 24 of 54 patients (44%) with a failed OXC dose >900 mg.

SIGNIFICANCE

The present study provides new insights into the doses of the commonly used ASMs such as OXC, CBZ, and VPA that can lead to seizure freedom as monotherapy or as combination therapy. The higher PDD/DDD ratio of OXC (0.99) than that of CBZ or VPA renders a generalized PDD/DDD comparison highly problematic.

A review of antiepileptic drugs: Part 1 occurrence, fate in aquatic environments and removal during different treatment technologies

Antiepileptic drugs (AEDs) are the main treatment for people with epilepsy. However, in recent years, more and more people are using them for other indications such as: migraine, chronic neuropathic pain, and mood disorders. Consequently, the prescriptions and consumption of these drugs are increasing worldwide. In WWTPs, AEDs can resist degradation processes, such as photodegradation, chemical degradation and/or biodegradation. Until now, only constructed wetlands and photocatalysis have shown good removal rates of AEDs from wastewater. However, their effectiveness depends on the specific conditions used during the treatment. Since the consumption of AEDs has increased in the last decade and their degradation in WWTPs is poor, these drugs have been largely introduced into the environment through the discharge of municipal and/or hospital effluents. Once in the environment, AEDs are distributed in the water phase, as suspended particles or in the sediments, suggesting that these drugs have a high potential for groundwater contamination. In this first part of the AEDs review is designed to fill out the current knowledge gap about the occurrence, fate and removal of these drugs in the aquatic environment. This is a review that emphasizes the characteristics of AEDs as emerging contaminants.

Involuntary human exposure to carbamazepine: A cross-sectional study of correlates across the lifespan and dietary spectrum

Treated wastewater (TWW) is increasingly used for agricultural irrigation, especially in arid and semi-arid regions. Carbamazepine is among the most frequently detected pharmaceuticals in TWW. Moreover, its uptake and accumulation have been demonstrated in crops irrigated with TWW. A previous controlled trial found that urine concentrations of carbamazepine were higher in healthy volunteers consuming TWW-irrigated produce as compared to freshwater-irrigated produce. The aim of the current study was to assess whether carbamazepine is quantifiable in urine of Israelis consuming their usual diets and whether concentrations vary according to age, personal characteristics and diet. In this cross-sectional study, we recruited 245 volunteers, including a reference group of omnivorous healthy adults aged 18-66; pregnant women; children aged 3-6 years; adults aged >75 years; and vegetarians/vegans. Participants provided spot urine samples and reported 24-hour and "usual" dietary consumption. Urinary carbamazepine levels were compared according to group, personal characteristics, health behaviors, and reported diet. Carbamazepine was detectable (≥1.66 ng/L) in urine of 84%, 76%, 75.5%, 66%, and 19.6% of the reference group, vegetarians, older adults, pregnant women, and children, respectively. Quantifiable concentrations (≥5.0 ng/L) of carbamazepine were found in 58%, 46%, 36.7%, 14%, and 0% of these groups, respectively (p = 0.001 for comparison of proportions across groups). In adults, higher carbamazepine concentrations were significantly associated (p < 0.05) with self-defined vegetarianism, usual consumption of dairy products and at least five vegetables/day, and no meat or fish consumption in the past 24-hours. This study demonstrates that people living in a water-scarce region with widespread TWW irrigation, are unknowingly exposed to carbamazepine. Individuals adhering to recommended guidelines for daily fresh produce consumption may be at higher risk of exposure to TWW-derived contaminants of emerging concern.

Transformation of lamotrigine by white-rot fungus Pleurotus ostreatus

One of the most persistent pharmaceutical compounds commonly found in treated wastewater is lamotrigine (LTG). It has also been detected in soils and crops irrigated with treated wastewater. Here we focused on the ability of the white-rot edible mushroom Pleurotus ostreatus to remove and transform LTG in liquid cultures. At concentrations of environmental relevance (1 and 10 μg L^-1) LTG was almost completely removed from the culture medium within 20 days. To elucidate the mechanism of LTG removal and transformation, we applied a physiological-based approach using inhibitors and a competing agent. These experiments were conducted at a higher concentration for metabolites detection. Based on identification of sulfur-containing metabolites and LTG N2-oxide and the effect of specific inhibitors, cytochrome P450 oxidation is suggested as one of the reaction mechanisms leading to LTG transformation. The variety and number of transformation products (i.e., conjugates) found in the current study were larger than reported in mammals. Moreover, known conjugates with glucuronide, glutathione, or cysteine/glycine, were not found in our system. Since the majority of the identified transformation products were conjugates of LTG, this study highlights the persistence of LTG as an organic pollutant in ecosystems exposed to wastewater.

Treatment with antiepileptic drugs in patients with stroke. A change in clinical practice may be required

BACKGROUND

Stroke prevention is an important socio-economic aim. Epilepsy and antiepileptic drugs (AEDs), roughly divided into enzyme-inducers and non-enzyme-inducers, have been associated with increased risk of stroke.

METHODS

A retrospective review of patients admitted with a diagnosis of anytime stroke and taking at least one AED was performed. A subgroup of subjects admitted for acute strokes was separately studied. Potential interactions between AEDs and other consumed medications were identified using MicroMedex and Lexi-Interact.

RESULTS

The study included 827 patients, 59% of them using 5-10 medications. Two thirds of the patients received at least one enzyme-inducer AED, with phenytoin being the most commonly used AED (38% of the patients). Among the subgroup of 82 patients admitted for stroke, 61% were prescribed AEDs after the stroke. More patients had large vessel and embolic strokes among these than among the patients that had strokes while on AEDs. Statins, antiplatelet drugs, antidiabetics and calcium channel blockers (CCBs) were the most frequently used non-AED drugs, by 56, 55, 30 and 28%, respectively. The most common combinations between AEDs and non-AED medications bearing risk for potential major interactions were those of AEDs with statins, warfarin, calcium channel blockers and anti-depressants.

CONCLUSIONS

A change in the AEDs prescription practice in stroke patients should be implemented, to avoid interactions with major groups of other medications prescribed to these patients.

Pharmacokinetics in Plants: Carbamazepine and Its Interactions with Lamotrigine

Carbamazepine and lamotrigine prescribed antiepileptic drugs are highly persistent in the environment and were detected in crops irrigated with reclaimed wastewater. This study reports pharmacokinetics of the two drugs and their metabolites in cucumber plants under hydroponic culture, testing their uptake, translocation, and transformation over 96 h in single and bisolute systems at varying pH. Ruling out root adsorption and transformations in the nutrient solution, we demonstrate that carbamazepine root uptake is largely affected by the concentration gradient across the membrane. Unlike carbamazepine, lamotrigine is adsorbed to the root and undergoes ion trapping in root cells thus its translocation to the shoots is limited. On the basis of that, carbamazepine uptake was not affected by the presence of lamotrigine, while lamotrigine uptake was enhanced in the presence of carbamazepine. Transformation of carbamazepine in the roots was slightly reduced in the presence of lamotrigine. Carbamazepine metabolism was far more pronounced in the shoots than in the roots, indicating that most of the metabolism occurs in the leaves, probably due to higher concentration and longer residence time. This study indicates that the uptake of small nonionic pharmaceuticals is passive and governed by diffusion across the root membrane.

Trends in utilization of benzodiazepine and Z-drugs in Israel

BACKGROUND

Studies on benzodiazepine (BZDs) as well as Zopiclone and Zolpidem (Z-drugs) utilization are important for estimating the prevalence of medical conditions, providing the basis for pharmacovigilance, and identifying temporal trends of consumption. Such studies that involve the Israeli population have not been conducted yet.

PURPOSE

Identify trends over time in utilization of BZDs and Z-drugs in a nationwide population in Israel.

METHODS

Data on BZD and Z-drugs utilization (for all indications) for the period 2005 to 2013 were obtained from pharmaceutical companies that distribute BZDs in Israel. Prevalence of BZD utilization was reported as defined daily doses (DDD)/1000 inhabitants/day.

RESULTS

The utilization of BZDs and Z-drugs aimed to treat sleeping disorders increased over the period of the study from 10.22 to 22.49 DDD/1000 inhabitants/day. The greatest increases in utilization of drugs established in Israel were observed for brotizolam (83%), zopiclone (59%), and zolpidem (94%). Decreases in use were recorded for lorazepam (14%), diazepam (16%), and oxazepam (27%). Use of hypnotic BZDs appeared to be relatively high, compared with the use of non-BZD hypnotics ("Z-drugs") such as zolpidem or zopiclone. Nationwide stressful conditions did not appear to be reflected in the annual BZD sales.

CONCLUSIONS

Conventional BZDs and Z-drugs remained the treatment of choice for sleeping disorders in Israel during the study period. These results are, in certain cases, in contrast to current practice recommendations and guidelines and point at a need in better dissemination of these guidelines among prescribers in Israel.

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.