Clinical pharmacology: drugs as a benefit and/or risk in sudden unexpected death in epilepsy?

Cost-Effectiveness of Zonisamide Versus Levetiracetam in Newly Diagnosed Focal Onset Epilepsy in Serbia

OBJECTIVES

When choosing initial therapy for epilepsy, the decision should be supported by studies that include both treatment outcome and costs. This is especially important for developing countries with restricted budgets because such circumstances are also characterized by higher epilepsy prevalence rates. The aim of this study was to compare cost-utility of zonisamide (ZNS) and levetiracetam (LEV) in patients with newly diagnosed focal-onset epilepsy in the Republic of Serbia.

METHODS

A 5-state, 3-month-cycle Markov model was created to compare ZNS and LEV. The model assumed that patients whose seizures were not controlled by treatment with either ZNS or LEV would be continued on carbamazepine in controlled-release form in the second cycle and would then be treated with a pregabalin add-on if still not adequately controlled. The perspective of the Serbian Republic Health Insurance Fund was chosen, and the time horizon was 15 years. Model results were obtained after Monte Carlo microsimulation of a sample with 1000 virtual patients. Both multiple one-way and probabilistic sensitivity analyses were performed.

RESULTS

After base-case analysis, LEV was dominated by ZNS because the net monetary benefit was positive (16 940.78 ± 22 572.26 Serbian dinars; €144.09 ± €191.99) and the incremental cost-effectiveness ratio was below the willingness-to-pay threshold of 3 Serbian gross domestic products per capita per quality-adjusted life-year gained. Multiple one-way and probabilistic sensitivity analyses confirmed the results of the base-case simulation.

CONCLUSIONS

ZNS has a more beneficial cost-effectiveness ratio than LEV for the treatment of newly diagnosed focal epilepsy in Serbian milieu.

Quantification and Evaluations of Catechin Hydrate Polymeric Nanoparticles Used in Brain Targeting for the Treatment of Epilepsy

To formulate novel chitosan (CS)-coated-PLGA-nanoparticles (NPs) using a central composite design approach and use them in order to improve brain bioavailability for catechin hydrate (CH) through direct nose-to-central nervous system (CNS) delivery for the evaluation of a comparative biodistribution study of CH by the newly developed ultra high performance liquid chromatography mass spectroscopy and mass spectroscopy (UHPLC-MS/MS) method in the treatment of epilepsy. For PLGA-NPs' preparation, a double emulsion-solvent evaporation method was used, where a four-factor, three-level central composite design was used to obtain the best nanoformulation. For the optimization, four independent variables were chosen, that is, PLGA, polyvinyl alcohol (PVA), sonication time, and temperature. The optimized PLGA-NPs were further coated with chitosan and assessed for drug release, nasal permeation study, as well as a comparative pharmacokinetic and pharmacodynamic study. Independent and dependent variables helped to optimize the best nanoformulation based on the composition of PLGA (50.0 mg), PVA (1.10%), sonication time (90.0 s), and temperature (25.0 °C). The values of dependent variables were observed, such as polydispersity index (PDI), particle size, and zeta potential (ZP)-that is, 0.106 ± 0.01, 93.46 ± 3.94 nm, and -12.63 ± 0.08 mV, respectively. The ZPs of CS-coated PLGA-NPs were changed from negative to positive value with some alteration in the distribution of particle size. Excellent mucoadhesive-nature of CS-CH-PLGA-NPs as compared with CH-S and CH-PLGA-NPs was seen, with a retention time of 0.856 min and m/z of 289.23/245.20 for CH, together with a retention time of 1.04 min and m/z of 301.21/151.21 for Quercetin as an internal standard (IS). For a linear range (1-1000 ng mL^-1), % accuracy (93.07-99.41%) and inter- and intraday % precision (0.39-4.90%) were determined. The improved C_max with area under curve (AUC)_0-24 was found to be highly significant (p < 0.001) in Wistar rats' brain as compared with the i.n. and i.v. treated group based on the pharmacokinetics (PK) results. Furthermore, CS-CH-PLGA-NPs were found to be more significant (p < 0.001) for the treatment of seizure threshold rodent models, that is, increasing current electroshock and pentylenetetrazole-induced seizures. A significant role of CS-CH-PLGA-NPs was observed, that is, p < 0.001, for the enhancement of brain bioavailability and the treatment of epilepsy.

A bioanalytical UHPLC based method used for the quantification of Thymoquinone-loaded-PLGA-nanoparticles in the treatment of epilepsy

To formulate a nanoformulation (PLGA-NPs) and to improve brain bioavailability for thymoquinone (THQ) through intranasal (i.n.) drug delivery, using a newly UHPLC-PDA developed the method and validated. Five different THQ-PLGA-NPs (THQ-N1 to THQ-N5) were prepared by emulsion solvent evaporation method. A new UHPLC method developed and validated for biodistribution studies in the rat’s brain, lungs and plasma. Optimized-THQ-N1-NPs showed a particle size of 97.36 ± 2.01 nm with a low PDI value of 0.263 ± 0.004, ZP of − 17.98 ± 1.09, EE of 82.49 ± 2.38% and DL of 5.09 ± 0.13%. THQ-N1-NPs showed sustained release pattern via in vitro release profile. A bioanalytical method was developed by UHPLC-PDA and validated for the evaluation of pharmacokinetics parameters, biodistribution studies, brain drug-targeting potential (89.89 ± 9.38%), and brain-targeting efficiency (8075.00 ± 113.05%) studies through intranasal administration which showed an improved THQ-brain- bioavailability, compared to i.v. Moreover, THQ-PLGA-NPs improved the seizure threshold treatment i.e. epilepsy increasing current electroshock (ICES) rodent models induced seizures in rats. A significant role of THQ-PLGA-NPs with high brain targeting efficiency of the nanoformulations was established. The reported data supports the treatment of epilepsy.

Cardiovascular effects of phentermine and topiramate: a new drug combination for the treatment of obesity

Weight loss can reduce the increased cardiovascular risk associated with obesity. Pharmacotherapy is a recognized weight loss treatment option; however, cardiovascular safety issues with some previous weight loss drugs raise concerns for newly approved pharmacotherapies. Phentermine is approved for short-term obesity treatment in conjunction with lifestyle modifications, but is commonly used chronically. Topiramate, approved for treating epilepsy and preventing migraines, also induces weight loss. A single-dose combination of low-dose phentermine and topiramate extended-release was recently approved by the United States Food and Drug Administration as an adjunct to lifestyle intervention for the chronic treatment of overweight/obese adults. This review summarizes and evaluates the cardiovascular risk/benefit profile associated with phentermine and topiramate, individually and in combination. Cardiovascular data associated with long-term use of phentermine and topiramate extended-release indicate that this combination may be a safe and effective option for reducing weight in overweight/obese patients at low-to-intermediate cardiovascular risk.

Retigabine as adjunctive therapy in adults with partial-onset seizures: integrated analysis of three pivotal controlled trials

We assessed the efficacy and tolerability of retigabine (RTG; international non-proprietary name)/ezogabine (EZG; US adopted name) as adjunctive therapy in adults with partial-onset seizures in an integrated analysis of three trials. Studies 205, 301 (NCT00232596), and 302 (NCT00235755) were randomized, double-blind, placebo-controlled studies in adults having ≥4 partial-onset seizures per 28 days and receiving 1-3 antiepileptic drugs with/without vagus nerve stimulator. Patients underwent titration to RTG/EZG 600, 900, or 1200 mg/day or to placebo followed by 8 or 12 weeks maintenance. For efficacy analyses, placebo was compared with RTG/EZG 600 and 900 mg/day in Studies 205 and 302, and RTG/EZG 1200 mg/day in Studies 205 and 301. Responder rates (≥50% reduction in baseline seizure frequency) were 35% and 45% for RTG/EZG 600 and 900 mg/day, respectively (placebo=21%; p<0.001), and 50% for RTG/EZG 1200 mg/day (placebo=24%, p<0.001). Reductions in 28-day total partial-seizure frequency (medians: placebo=14%; 600 mg/day=26%, p=0.003; 900 mg/day=37%, p<0.001; placebo=15%; 1200 mg/day=39%, p<0.001) were significantly greater with all RTG/EZG doses vs. placebo from baseline to the double-blind phase, and similarly during the maintenance phase. The most commonly reported (>10%) treatment-emergent adverse events were dizziness, somnolence, headache, and fatigue. RTG/EZG demonstrated efficacy and was generally tolerated as adjunctive therapy in adults with partial-onset seizures in this integrated analysis.

Forensic antiepileptic drug levels in autopsy cases of epilepsy

A 1-year retrospective coroner-based forensic examination of causes of death among persons with a history of epilepsy was conducted at the Allegheny County Coroner's Office to evaluate the phenomenon of sudden unexplained/unexpected death in epilepsy (SUDEP), a diagnosis of exclusion. All cases at the Coroner's Office from January 1, 2001 through December 31, 2001, were examined. Review of a total of 1200 autopsied deaths revealed 12 cases with a past medical history of seizure disorder on the death certificate, which listed seizure disorder as the immediate cause of death or contributory cause of the death. Of the 7 men with seizure disorders, 5 were categorized as definite SUDEP and 2 as possible SUDEP. Of the 5 women with seizure disorders, 2 were listed as definite SUDEP, 2 as possible, and 1 as non-SUDEP because the convulsive seizures developed from a grade II glial tumor. Postmortem findings were evaluated for 11 cases; 1 body was decomposed. Toxicological screens were carried out on blood, bile, urine, and eye fluid for all 12. Antiepileptic drug (AED) levels detected in postmortem toxicological analysis were examined. AED levels were determined in 7 cases. Four of 7 had subtherapeutic AED levels, 2 had therapeutic levels, and only 1 victim of SUDEP had levels above the therapeutic range. Five cases had no detectable AED levels. AED levels at autopsy were either absent or subtherapeutic in 9 of 10 SUDEP cases, findings consistent with the likelihood of poor AED compliance. Subtherapeutic levels of AEDs may be a risk factor for SUDEP that could contribute to increased interictal and/or ictal epileptiform activity with associated autonomic dysfunction leading to disturbance of heart rate, heart rhythm, and/or blood pressure.

Dysembryoplastic neuroepithelial tumor and probable sudden unexplained death in epilepsy: a case report

INTRODUCTION

This is the first report of the case of a patient with a natural history of dysembryoplastic neuroepithelial tumor associated with probable sudden unexplained death in epilepsy. These tumors are benign, arising within the supratentorial cortex. Over 100 cases have been reported in the literature since the first description by Daumas-Duport in 1988.

CASE PRESENTATION

A 24- year-old Caucasian woman had a long period of intractable complex partial seizures, sometimes with tonic-clonic generalization and neuropsychological abnormalities. Magnetic resonance imaging showed a cortico-subcortical parietal tumor with all the characteristics of these types of tumors. After 14 years of evolution, our patient died suddenly during sleep.

CONCLUSION

To the best of our knowledge, this is the first case of probable sudden unexplained death in symptomatic epilepsy due to dysembryoplastic neuroepithelial tumor with natural history. Early and complete excision, with functional studies before and during the surgery, leads to better control of seizures, avoiding neuropsychological changes and the risk of death. Patients with refractory epilepsy should be evaluated for any sleep disorders and should have complete cardiology assessments including electrocardiographic evaluation of cardiac rhythm disturbances.

Methods for ECG evaluation of indicators of cardiac risk, and susceptibility to aconitine-induced arrhythmias in rats following status epilepticus

Lethal cardiac arrhythmias contribute to mortality in a number of pathological conditions. Several parameters obtained from a non-invasive, easily obtained electrocardiogram (ECG) are established, well-validated prognostic indicators of cardiac risk in patients suffering from a number of cardiomyopathies. Increased heart rate, decreased heart rate variability (HRV), and increased duration and variability of cardiac ventricular electrical activity (QT interval) are all indicative of enhanced cardiac risk. In animal models, it is valuable to compare these ECG-derived variables and susceptibility to experimentally induced arrhythmias. Intravenous infusion of the arrhythmogenic agent aconitine has been widely used to evaluate susceptibility to arrhythmias in a range of experimental conditions, including animal models of depression and hypertension, following exercise and exposure to air pollutants, as well as determination of the antiarrhythmic efficacy of pharmacological agents. It should be noted that QT dispersion in humans is a measure of QT interval variation across the full set of leads from a standard 12-lead ECG. Consequently, the measure of QT dispersion from the 2-lead ECG in the rat described in this protocol is different than that calculated from human ECG records. This represents a limitation in the translation of the data obtained from rodents to human clinical medicine. Status epilepticus (SE) is a single seizure or series of continuously recurring seizures lasting more than 30 min, and results in mortality in 20% of cases. Many individuals survive the SE, but die within 30 days. The mechanism(s) of this delayed mortality is not fully understood. It has been suggested that lethal ventricular arrhythmias contribute to many of these deaths. In addition to SE, patients experiencing spontaneously recurring seizures, i.e. epilepsy, are at risk of premature sudden and unexpected death associated with epilepsy (SUDEP). As with SE, the precise mechanisms mediating SUDEP are not known. It has been proposed that ventricular abnormalities and resulting arrhythmias make a significant contribution. To investigate the mechanisms of seizure-related cardiac death, and the efficacy of cardioprotective therapies, it is necessary to obtain both ECG-derived indicators of risk and evaluate susceptibility to cardiac arrhythmias in animal models of seizure disorders. Here we describe methods for implanting ECG electrodes in the Sprague-Dawley laboratory rat (Rattus norvegicus), following SE, collection and analysis of ECG recordings, and induction of arrhythmias during iv infusion of aconitine. These procedures can be used to directly determine the relationships between ECG-derived measures of cardiac electrical activity and susceptibility to ventricular arrhythmias in rat models of seizure disorders, or any pathology associated with increased risk of sudden cardiac death.

Predicting drug-induced slowing of conduction and pro-arrhythmia: identifying the 'bad' sodium current blockers

BACKGROUND AND PURPOSE

The regulatory guidelines (ICHS7B) for the identification of only drug-induced long QT and pro-arrhythmias have certain limitations.

EXPERIMENTAL APPROACH

Conduction time (CT) was measured in isolated Purkinje fibres, left ventricular perfused wedges and perfused hearts from rabbits, and sodium current was measured in Chinese hamster ovary cells, transfected with Na(v)1.5 channels.

KEY RESULTS

A total of 355 compounds were screened for their effects on CT: 32% of these compounds slowed conduction, 65% had no effect and 3% accelerated conduction. Lidocaine and flecainide, which slow conduction, were tested in more detail as reference compounds. In isolated Purkinje fibres, flecainide largely slowed conduction and markedly increased triangulation, while lidocaine slightly slowed conduction and did not produce significant triangulation. Also in isolated left ventricular wedge preparations, flecainide largely slowed conduction in a rate-dependent manner, and elicited ventricular tachycardia (VT). Lidocaine slightly slowed conduction, reduced Tp-Te and did not induce VT. Similarly in isolated hearts, flecainide markedly slowed conduction, increased Tp-Te and elicited VT or ventricular fibrillation (VF). The slowing of conduction and induction of VT/VF with flecainide was much more evident in a condition of ischaemia/reperfusion. Lidocaine abolished ischaemia/reperfusion-induced VT/VF. Flecainide blocked sodium current (I(Na)) preferentially in the activated state (i.e. open channel) with slow binding and dissociation rates in a use-dependent manner, and lidocaine weakly blocked I(Na).

CONCLUSION AND IMPLICATIONS

Slowing conduction by blocking I(Na) could be potentially pro-arrhythmic. It is possible to differentiate between compounds with 'good' (lidocaine-like) and 'bad' (flecainide-like) I(Na) blocking activities in these models.

Epilepsy and sudden death: personal reflections and call for global action

To solve the mystery of sudden unexpected death in persons with epilepsy (SUDEP), a global focus is needed to identify persons at risk, develop treatment regimens, and prevent its occurrence. A world wide network of professionals must focus on basic scientific research programs and clinical and epidemiology studies. Team work among different multidisciplinary professionals in clinical settings and within and among laboratories should address the global issues of SUDEP. If the correct term 'SUDEP' is used on autopsy reports and if verbal autopsies postmortem are conducted when needed, the true incidence of SUDEP may be found to be much higher than previously thought and the market for new antiepileptics and other drugs to prevent SUDEP will be larger. Symposia should discuss new data and lessons learned from the last 20 to 30 years to be applied by scientists and clinicians worldwide to gain a better understanding of SUDEP. 'Think out of the box' when evaluating an established animal model with potential for modification(s) to study mechanism(s) of SUDEP. Multiple relevant animal models are needed to understand the pathophysiology of SUDEP, hypothesize about effective treatments, develop small pilot studies in persons with epilepsy, and conduct confirmatory large-scale clinical trials. The fields of pharmacology, clinical pharmacology, and cardiology have much to offer as we work to improve compliance, develop new antiepileptic drugs, and apply different categories of drugs to resolve the mystery of SUDEP. Ambulatory simultaneous EKG and EEG telemetry monitoring of patients at risk for sudden death will help identify cardiac vs. brain epileptogenic triggers for treatment to decrease risk of SUDEP. Respiratory function monitoring is also needed. Academic fellowships and competitions for medical students, postdoctoral fellows, residents and faculty will attract medical and graduate trainees to work on SUDEP. Grant funding is essential to move the SUDEP knowledge base forward. Leaders must solve the global mystery of SUDEP using a leadership philosophy foundation that provides innovative vision and approaches for SUDEP research and teaching programs. The interaction of teaching and research is essential: while a student is learning how to conduct research he must simultaneously learn to become a teacher. Medical and graduate leaders must provide vision and a fertile environment to teach students of today to become the self learners and leaders of tomorrow to find solutions for SUDEP.

Status epilepticus produces chronic alterations in cardiac sympathovagal balance

PURPOSE

Status epilepticus (SE) activates the autonomic nervous system, increasing sympathetic nervous system control of cardiac function during seizure activity. However, lasting effects of SE on autonomic regulation of the heart, which may contribute to mortality following seizure activity, are unknown. Therefore, autonomic control of cardiac function was assessed following SE.

METHODS

Using Sprague-Dawley rats after 1-2 weeks of recovery from lithium-pilocarpine-induced SE or control procedures, we tested overall sympathovagal control of the heart, the individual contributions of the sympathetic and parasympathetic components of the autonomic nervous system, and baroreflex sensitivity.

RESULTS

SE induced a chronic shift in sympathovagal balance toward sympathetic dominance resulting from decreased parasympathetic activity. Baroreflex sensitivity to increased blood pressure was also decreased, likely resulting from diminished vagal activation.

DISCUSSION

Chronic alterations in autonomic regulation of cardiac function, characterized by increased sympathetic dominance, occur following SE and likely contribute to subsequent increased cardiac risk and mortality.

Topiramate in patients with epilepsy and intellectual disability

This noninterventional single-arm study explored effectiveness and behavioral outcomes in intellectually disabled patients treated with topiramate for epilepsy. Data from 21 patients diagnosed with cerebral palsy were available for evaluation. Behavioral changes were assessed using the validated Aberrant Behavior Checklist and Matson Evaluation of Social Skills for Individuals with Severe Retardation (MESSIER) scales. Some improvement in nearly all behavioral aspects was observed under concomitant topiramate therapy; for example, the Aberrant Behavior Checklist total score changed from 33.7+/-25.8 to 25.3+/-19.1 (P=0.047). In addition, seizure frequency decreased from 16.1+/-22.2/4 weeks to 12.2+/-17.0/4 weeks (N=21, P=0.164). Fifty-two percent of the patients experienced at least 50% seizure reduction during the 24-week treatment period. The safety profile is in accordance with the current Summary of Product Characteristics of Topiramate. Two unexpected deaths were attributed to sudden unexpected death in epilepsy.

A review of sudden unexpected death in epilepsy: prediction of patients at risk

This review attempts to provide up-to-date quantitative data from published reports on sudden unexpected death in epilepsy (SUDEP) appearing on Medline and, especially, to provide a means to predict the probability of SUDEP in a given patient. The mean incidence of SUDEP was 1.8/1000, similar to the median of 1.5. The mean standardized mortality ratio was 6.8, and the mean percentage of SUDEP cases among deaths from epilepsy was 16.6. Seventeen risk factors were identified, each given a value according to the number of studies in the literature that specified that condition as a significant risk. The addition of these 17 values then indicated the risk for a given patient. The author calculated these for a group of 91 patients who died of SUDEP and also for 91 live patients. Many of their values for the different risks were significantly different. The sensitivity of these SUDEP values was 71.3%, the specificity 81.8%, and the positive predictive value 84.6%. A discussion includes the question of whether the death in SUDEP is primarily cardiac or pulmonary and the suggestion that it may be either or both in a given patient. The most important risk factor in this study was noncompliance with antiepileptic medication, and the main message of this study to caregivers is that therapeutic drug levels are crucial to avoid SUDEP.

Quantification of respiratory parameters in patients with temporal lobe epilepsy

Dysfunction affecting cardiac or pulmonary systems has been postulated as a major factor in sudden death in epilepsy (SUDEP). Whilst the majority of studies of cardiorespiratory function have focused on changes during seizures, here we investigate whether epilepsy influences basal respiratory parameters in patients with temporal lobe epilepsy (TLE) during the interictal period. Spirometry was performed in 10 females and 10 males. Measurements of Vital Capacity (VC), Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1) and ratios of FEV1 to FVC (FEV1/FVC) were obtained, and these values were analyzed as percentages of predicted values. None of the patients had chronic obstructive pulmonary disease and no significant alterations in respiratory function tests were found among these patients. No association between seizure frequency, antiepileptic drugs and SUDEP could be found in this study. Although the study did not identify any specific respiratory abnormality in TLE patients during the interictal period, re-evaluation of clinical data on pulmonary disorders in people with epilepsy should be better investigated.

The mystery of sudden death: mechanisms for risks

This review addresses the possible overlapping mechanisms that may apply to the risk of sudden unexpected death occurring in epilepsy and in cardiac disease. It explores the interaction between the central and peripheral autonomic nervous systems and the cardiopulmonary systems. Included is a discussion of the potential interactive role of genetically determined subtle cardiac risk factors for arrhythmias with a predisposition for seizure-related cardiac arrhythmias. We address the possible mechanisms that are operant in producing both epileptogenic and cardiogenic arrhythmias. Finally, we speculate about potential preventive measures to minimize the risk of both sudden unexpected death in epilepsy and sudden cardiac death.

Mortality in epilepsy

All studies report an increased mortality risk for people with epilepsy compared with the general population. Population-based studies have demonstrated that the increased mortality is often related to the cause of the epilepsy. Common etiologies include neoplasia, cerebrovascular disease, and pneumonia. Deaths in selected cohorts, such as sudden unexpected death in epilepsy (SUDEP), status epilepticus (SE), suicides, and accidents are more frequently epilepsy-related. SUDEP is a particular cause for concern in younger people, and whether and when SUDEP should be discussed with patients with epilepsy remain problematic issues. Risk factors for SUDEP include generalized tonic-clonic seizures, increased seizure frequency, concomitant learning disability, and antiepileptic drug polypharmacy. The overall incidence of SE may be increasing, although case fatality rates remain constant. Mortality is frequently secondary to acute symptomatic disorders. Poor compliance with treatment in patients with epilepsy accounts for a small proportion of deaths from SE. The incidence of suicide is increased, particularly for individuals with epilepsy and comorbid psychiatric conditions. Late mortality figures in patients undergoing epilepsy surgery vary and are likely to reflect differences in case selection. Future studies of mortality should be prospective and follow agreed guidelines to better quantify risk and causation in individual populations.

SUDEP in the Netherlands: A retrospective study in a tertiary referral center

OBJECTIVE

To evaluate risk factors for sudden and unexpected death in epilepsy (SUDEP) in a high-risk population, i.e. patients treated in a Dutch tertiary referral center for epilepsy.

METHODS

All patients who died between January 1999 and April 2004 while under treatment of the epilepsy center were identified. Based on clinical data, deaths were classified as definite, probable, possible or non-SUDEP. Potential risk factors were compared in SUDEP cases and non-SUDEP cases.

RESULTS

SUDEP incidence was 1.24 per 1000 patient years. SUDEP patients died at a younger age than patients from the control group of non-SUDEP deaths with epilepsy and had an earlier onset of epilepsy. However, the frequently mentioned factors in previous studies, i.e. male sex, generalized tonic-clonic seizures, high seizure frequency, specific AEDs, polytherapy with several AEDs, mental retardation, psychiatric illness and psychotropic comedication, were not found to be correlated with SUDEP.

CONCLUSIONS

Even in this high-risk population of patients with refractory epilepsy, treated in a tertiary referral center, SUDEP is not a frequently occurring phenomenon. Specific risk factors could not be identified within an already high-risk population.

Pediatric experience with sudden unexplained death in epilepsy at a tertiary epilepsy center

Sudden unexplained death in epilepsy is rare in children, and few studies report risk factors. We reviewed our experience with 17 cases of sudden unexplained death in epilepsy to determine risk factors in children. The charts of all patients with onset of epilepsy at less than age 18 years who suffered sudden unexplained death in epilepsy between August 1992 and April 2004 at our epilepsy center were retrospectively reviewed. Deaths were classified as possible, probable, or definite sudden unexplained death in epilepsy. There were seven cases of definite, nine cases of probable, and one case of possible sudden unexplained death in epilepsy. Generalized tonic-clonic seizures and prone position during sleep were found to be major risk factors. Sudden unexplained death in epilepsy in children and adolescents is associated with convulsive seizures, and aggressive treatment of nocturnal generalized tonic-clonic seizures might help lower the occurrence.

Stress and sudden death

Cardiac patients, psychiatric patients, and certain ethnic groups experiencing acute stressful circumstances are at risk for unexpected sudden death. Although stress is associated with changes in autonomic neural function, its role as a potential risk factor for sudden unexpected death in epilepsy (SUDEP) is not known. The association of epilepsy with cardiac abnormalities, such as neurogenic arrhythmias and microscopic perivascular and interstitial fibrosis, and with depression and anxiety indicates that emotional stress should be evaluated as a potential risk factor for SUDEP. The impact of adverse emotional states on the autonomic control of cardiac rhythm is a known important factor leading to cardiac dysrhythmias in humans and other species. The interaction between emotional factors and the arrythmogenic potential of epileptiform discharges and the possibility of benefit from stress management intervention need to be investigated.

Trends in suicide by drowning in the elderly in England and Wales 1979-2001

BACKGROUND

Suicide by drowning increases with age but its rates vary between countries and among communities. Drowning suicide rates in some of the available studies may have been over reported or under reported because of misclassification.

OBJECTIVE

This study presents data on the time trends, age/sex mortality rates from death by drowning in the elderly in England and Wales between 1979 and 2001. All coroners' verdicts in death by drowning; suicide, deaths undetermined whether accidentally or purposely inflicted were examined.

METHODS

Counts of suicide due to drowning and submersion [ICD 9 codes; E954] and undetermined injury deaths [E984] (WHO, 1977), reported in England and Wales between 1979 and 2001 were obtained from National Statistics (ONS).

RESULTS

There has been a gradual reduction in suicide by drowning in men and women by more than a third the observed count in 1979 (p < 0.01). However, this decline was less evident in the elderly particularly those over the age of 75. Elderly drownings appear to attract more verdicts of suicide compared to younger age groups (Odds Ratio 4.3 95% CI 2.3-8.3). Women, particularly elderly, are more likely to have a suicide verdict returned in drowning compared to men (Odds Ratio 1.5 95% CI 1.1-1.6).

CONCLUSIONS

The high rate of open verdicts in elderly drowning over the study period and compared to any other method of fatal self harm in England and Wales confirms the difficulties in reaching a firm conclusion in drowning death. Therefore combining suicide and all undetermined deaths in drowning as a matter of course, in nationally collected statistics, may result in grossly exaggerated rates and misleading trends in suicidal drowning. Suicide by drowning is probably not amenable to prevention and although the elderly are often thought to benefit more from suicide prevention than younger adults, the study findings seem to suggest that this is not likely to be the case in drowning.

Suicide and undetermined death by drowning

Background Incidence of drowning varies among countries and even communities within the same country. The manner of death may remain undetermined even when the diagnosis of drowning is confirmed or excluded. It is expected that drowning suicide rates in some of the available studies may have been over- or under-reported because of misclassification. Objectives This study presents data on the time trends, age/sex mortality rates from death by drowning in England and Wales between 1979 and 2001. All coroners' verdicts in death by drowning; suicide, deaths undetermined whether accidentally or purposely inflicted were examined. Methods Counts of suicide due to drowning and submersion (ICD 9 codes; E954) and undetermined injury deaths (E984) 1 , reported in England and Wales between 1979 and 2001 were obtained from National Statistics (ONS). National population estimates were used to calculate age-specific rates and age-standardised rates of death by drowning. Results Over the last 23 years, there has been a gradual and significant reduction in drowning deaths. The decline in drowning suicide was less evident in the elderly, particularly those over the age of 75. During the study period, 62 and 38% of all death by drowning attracted an open verdict and suicide, respectively. Elderly drowning appear to attract more verdicts of suicide compared to younger age groups (odds ratio 4.3, 95% CI 2.3-8.3). Women, particularly elderly, are more likely to have a suicide verdict returned in drowning compared to men (odds ratio 1.5, 95% CI 1.1-1.6). Conclusion The high rate of open verdicts in death by drowning over the study period and compared to any other method of fatal self harm in England and Wales confirms the difficulties in reaching a firm conclusion in drowning death. Combining suicide and all undetermined deaths in drowning in nationally collected statistics may result in grossly exaggerated rates and misleading trends in suicidal drowning.

Cardiorespiratory findings in sudden unexplained/unexpected death in epilepsy (SUDEP)

Sudden unexplained/unexpected death in epilepsy (SUDEP), with an incidence of 0.35-9.3/1000 patient-years depending on the severity of epilepsy, remains a diagnostic and therapeutic challenge. Potential pathomechanisms comprise cardiac arrhythmia, due to myocardial ischemia, electrolyte disturbances, arrhythmogenic drugs, or transmission of the epileptic activity via the autonomic nervous system to the heart, and central or obstructive apnea. In most studies on SUDEP, data are lacking about the family and patient's own clinical history, cardiovascular symptoms, concomitant diseases and prior findings. Whether arterial hypertension, diabetes, hypercholesterolemia, other neurologic disorders, lung diseases, smoking or electrolyte disturbances are risk factors for SUDEP is unknown. Whereas cardiac dysfunction during seizures has been documented by electrocardiography, and cardiac abnormalities are found in up to 33% of SUDEP cases autoptically, investigations between seizures found only little cardiac abnormalities. More knowledge about the cardiovascular and pulmonary status of epileptic patients during, immediately after and between seizures is needed, which may contribute to better understand and possibly prevent SUDEP by measures like "cardioprotective" drugs, respiratory therapy or implantation of a cardioverter/defibrillator.