The ketogenic diet for intractable epilepsy in adults: preliminary results

A Modified Atkins Diet Is Effective for the Treatment of Intractable Pediatric Epilepsy

PURPOSE

The Atkins diet may induce ketosis as does the ketogenic diet, without restrictions on calories, fluids, protein, or need for an inpatient fast and admission. Our objective was to evaluate the efficacy and tolerability of a modified Atkins diet for intractable childhood epilepsy.

METHODS

Twenty children were treated prospectively in a hospital-based ambulatory clinic from September 2003 to May 2005. Children aged 3-18 years, with at least three seizures per week, who had been treated with at least two anticonvulsants, were enrolled and received the diet over a 6-month period. Carbohydrates were initially limited to 10 g/day, and fats were encouraged. Parents measured urinary ketones semiweekly and recorded seizures daily. All children received vitamin and calcium supplementation.

RESULTS

In all children, at least moderate urinary ketosis developed within 4 days (mean, 1.9). Sixteen (80%) completed the 6-month study; 14 chose to remain on the diet afterward. At 6 months, 13 (65%) had >50% improvement, and seven (35%) had >90% improvement (four were seizure free). Mean seizure frequency after 6 months was 40 per week (p = 0.005). Over a 6-month period, mean serum blood urea nitrogen increased from 12 to 17 mg/dl (p = 0.01); creatinine was unchanged. Cholesterol increased from 192 to 221 mg/dl, (p = 0.06). Weight did not change significantly (34.0-33.7 kg); only six children lost weight. A stable body mass index over time correlated with >90% improvement (p = 0.004).

CONCLUSIONS

A modified Atkins diet is an effective and well-tolerated therapy for intractable pediatric epilepsy.

Ketogenic diet decreases circulating concentrations of neuroactive steroids of female rats

Ketogenic diet (KD) is used to manage intractable epilepsy; however, the mechanisms underlying its therapeutic effects are not known. Steroid hormones, such as progesterone and testosterone, are derived from cholesterol, and are readily 5alpha-reduced to dihydroprogesterone and dihydrotestosterone, which are subsequently converted to 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP) and 3alpha-androstanediol, neuroactive steroids that can influence seizures. The present study examined the effects of the KD on circulating concentrations of these neuroactive steroids, and their precursors, in intact female rats. Thirty-six, 22-day-old female Sprague-Dawley rats (weaned at 21 days) were fasted for 8 hours prior to placement on one of three dietary regimens for 6 weeks: ad libitum chow, calorie-restricted chow, or KD. After 6 weeks of the diet, when six rats in each dietary condition were in diestrus and six were in behavioral estrus, all rats were administered pentylenetetrazole (PTZ, 70 mg/kg, i.p.). The latency and incidence of seizures were recorded by an observer who was uninformed of the estrous cycle and dietary treatment conditions of the rats. Immediately after each test, trunk blood was obtained for later measurement of pregnane (progesterone, dihydroprogesterone, 3alpha,5alpha-THP) and androstane (testosterone, dihydrotestosterone, 3alpha-androstanediol) neuroactive steroid concentrations in plasma by radioimmunoassay. KD tended to lengthen the latency to, and significantly reduced the number of, PTZ-induced barrel roll seizures. KD also significantly reduced plasma levels of the pregnane (dihydroprogesterone, 3alpha,5alpha-THP) and androstane (dihydrotestosterone, 3alpha-androstanediol) 5alpha-reduced metabolites. These data suggest that levels of pregnane and androstane neuroactive steroids, or their precursors, may underlie some of the antiseizure effects of KD.

Ketogenic Diet in Patients with Dravet Syndrome

PURPOSE

The ketogenic diet (KD) has been used as a therapeutic alternative to antiepileptic drugs (AEDs) for refractory epilepsy. Severe myoclonic epilepsy in infants or Dravet syndrome (DS) is one of the most malignant epileptic syndromes. In this retrospective study, we evaluated the efficacy and tolerability of the KD in patients with diagnostic criteria of DS.

METHODS

Between March 1, 1990, and August 31, 2004, 52 patients who met diagnostic criteria for DS were enrolled in a study at our department. Twenty of them were placed on the KD with the Hopkins protocol and followed up for a minimum of 1 year.

RESULTS

Three of the 20 original children stayed on the diet for 12 months, four children for 2 years, four children for 3 years, and two children for 4 years. One year after initiating the diet, 13 (65%) of the initial patients remained on the diet. Two (15%) patients were seizure free, eight (61.7%) children had a 75-99% decrease in seizures, and the remaining three (23%) children had a 50-74% decrease in seizures. Thus 1 year after starting the diet, 10 (77%) children had achieved a >75% decrease in their seizures. Four patients have been off the diet for >2 years; one of them is seizure free, two have sporadic seizures, and one, who abandoned the diet after 2 years of adhering to it, relapsed. No differences in seizure control when compared with age, sex, or seizure type were found.

CONCLUSIONS

Considering the severity and intractability of seizures in patients with DS, the fact that 10 of the 13 children who remained on the diet had a significant reduction in number of seizures shows that the KD is at present an interesting therapeutic alternative. Even in patients in whom seizure reduction was not dramatic, quality of life improved, and in all of them, the number of AEDs was reduced to one or two. We consider that children with DS should be offered the KD immediately after three adequate trials of AEDs have failed.

A comparison of the ability of a 4:1 ketogenic diet and a 6.3:1 ketogenic diet to elevate seizure thresholds in adult and young rats

PURPOSE

The pentylenetetrazol (PTZ) infusion test was used to compare seizure thresholds in adult and young rats fed either a 4:1 ketogenic diet (KD) or a 6.3:1 KD. We hypothesized that both KDs would significantly elevate seizure thresholds and that the 4:1 KD would serve as a better model of the KD used clinically.

METHODS

Ninety adult rats and 75 young rats were placed on one of five experimental diets: (a) a 4:1 KD, (b) a control diet balanced to the 4:1 KD, (c) a 6.3:1 KD, (d) a standard control diet, or (e) an ad libitum standard control diet. All subjects were seizure tested by using the PTZ infusion test. Blood glucose and beta-hydroxybutyrate (beta-OHB) levels were measured.

RESULTS

Neither KD elevated absolute "latencies to seizure" in young or adult rats. Similarly, neither KD elevated "threshold doses" in adult rats. In young rats, the 6.3:1 KD, but not the 4:1 KD, significantly elevated threshold doses. The 6.3:1 KD group showed poorer weight gain than the 4:1 KD group when compared with respective controls. The most dramatic discrepancies were seen in young rats.

CONCLUSIONS

"Threshold doses" and "latency to seizure" data provided conflicting measures of seizure threshold. This was likely due to the inflation of threshold doses calculated by using the much smaller body weights found in the 6.3:1 KD group. Ultimately, the PTZ infusion test in rats may not be a good preparation to model the anticonvulsant effects of the KD seen clinically, especially when dietary treatments lead to significantly mismatched body weights between the groups.

The ketogenic diet

BACKGROUND

The ketogenic diet is a low-carbohydrate, adequate-protein, and high-fat diet with a long history of use for the treatment of intractable seizures in children. This dietary therapy has been enjoying increasing popularity in recent years, despite the availability of increasing numbers of new antiepileptic drugs and surgical treatments.

REVIEW SUMMARY

The authors review the history of the ketogenic diet, the traditional protocol in initiating it, possible mechanisms of its action, evidence for efficacy, and side effects. In addition, they highlight some of the areas of active research in this field as well as future directions and unanswered questions.

CONCLUSION

The ketogenic diet is an efficacious and relatively safe treatment of intractable seizures. Despite its long history, however, much remains unknown about the diet, including its mechanisms of action, the optimal protocol, and the full range of its applicability. Investigations of the diet are providing new insight into the mechanisms behind seizures and epilepsy itself, as well as possible new therapies.

Nonpharmacological treatment options for epilepsy

Approximately one third of children with epilepsy have persistent seizures despite trials of multiple antiepileptic medications. For some of these patients, epilepsy surgery may provide freedom from seizures. However, in many cases, epilepsy surgery is not a viable treatment option. Nonpharmacological approaches are a useful adjunct to help manage seizures in these children. This review examines the role of vagus nerve stimulation, the ketogenic diet, and various forms of EEG biofeedback therapy in children with intractable epilepsy. Although the mechanism of action is not known precisely for any of these adjunctive therapies, they add an important and evolving dimension to the management of difficult to control epilepsy in children. In addition, pyridoxine-dependent seizures are discussed as an example of an etiology of refractory seizures that responds well to replacement therapy.

Effect of the ketogenic diet on the activity level of Wistar rats

Children, adolescents, and adults with epilepsy often also show symptoms associated with attention-deficit/hyperactivity disorder (ADHD). The ketogenic diet, which is administered to children with epilepsy refractory to drug therapy, seems to improve behavior in individuals with symptoms of ADHD. The basis for this improvement is unknown, although it seems to be unrelated to seizure control. The present research was designed to investigate the effect of two ketogenic diets on the behavior of normal adult male rats. Two experiments were conducted. In experiment 1, 36 subjects were placed on one of three diets: a control diet, a 6.3:1 ketogenic diet, and a 4:1 ketogenic diet. In experiment 2, 20 subjects were placed either on a control diet or on a 4:1 ketogenic diet. The activity level of each subject was measured using an open field test. Time spent immobile, grooming, and in exploratory behavior was measured for 600 s. Subjects were tested once before initiation of the diets and once while on the diets. No significant group differences were found in activity level before initiation of the diets. After initiation of the diets, subjects in both ketogenic groups showed a significantly lower activity level than the rats on the control diet. The ketogenic diet decreases activity level in an animal model. This behavioral change may relate to the improved behavior seen when children with symptoms of ADHD are placed on the diet.

Dietary approaches to epilepsy treatment: old and new options on the menu

Dietary therapies represent a potentially valuable adjunct to other epilepsy treatments, such as anticonvulsant medications, epilepsy surgery, and vagus nerve stimulation. Although the ketogenic diet (high fat, adequate protein, low carbohydrate) is the most well-established dietary therapy for epilepsy, other possible approaches include the Atkins diet (high fat, high protein, low carbohydrate), a diet enriched in polyunsaturated fatty acids, or overall restriction of calorie intake. This review discusses the current clinical status of each of these dietary approaches and suggests possible mechanisms by which they might suppress neuronal hyperexcitability and seizures.

Familiarity with, knowledge of, and attitudes toward epilepsy in residents of Seoul, South Korea

BACKGROUND AND PURPOSE

The aim of this study was to investigate the perceptions of epilepsy in Seoul, South Korea, a country where social stigma toward epilepsy is still pronounced.

METHODS

We randomly selected 1000 persons living in Seoul and performed telephone interviews regarding public awareness, knowledge, and attitudes toward epilepsy.

RESULTS

Among 1000 respondents, the 92% who had read or heard about epilepsy became the subjects of the study. Word of mouth was most often referenced as a source of knowledge (78%). Forty-seven percentage believed that epilepsy is inheritable, whereas 5% thought that epilepsy is a mental illness. Marriage of their children to an epileptic person, childbearing by women with epilepsy, and employing a person with epilepsy were opposed by more than 50% of respondents. The reasons for the negative attitudes were that epilepsy was hereditary and untreatable (P < 0.05, respectively).

CONCLUSIONS

Our study revealed that there still remains negative attitudes regarding the marriage, childbearing, and employment of persons with epilepsy, which may stem from misconceptions about the cause and treatability of epilepsy, possibly due in part to the influence of herbal medicine, and South Korea's ethnic homogeneity. Public health education either through media or school health education is urgently needed to improve knowledge about, and attitudes toward epilepsy.

Non-invasive detection of ketosis and its application in refractory epilepsy

Ketosis is believed to be necessary to the anticonvulsant mechanism of the ketogenic diet; however, the relationship between ketosis and seizure control has not been established. The various analytical methods for the assessment of ketosis are reviewed, and their application in the area of epilepsy and the ketogenic diet is evaluated. The clinical challenges inherent in interpreting measures of ketosis are discussed, as are suggestions for future studies.

Assessing the efficacy of antiepileptic treatments: the ketogenic diet

PURPOSE

To evaluate the evidence for determining if the ketogenic diet is an effective treatment for epilepsy.

METHODS

A literature review of published data over the past 80 years concerning the ketogenic diet was performed, focusing on efficacy, tolerability, age of patient population, as well as study design.

RESULTS

There have been several studies involving prospective and retrospective studies showing the ketogenic diet to be a very efficacious treatment in epilepsy, particularly epilepsy in childhood. However, no Class 1 studies have been published concerning the efficacy of the ketogenic diet.

CONCLUSIONS

The ketogenic diet appears to be a very effective treatment for epilepsy, particularly in childhood. It would be beneficial to have Class 1 studies available to help better define the role of the diet both in children and adults.

Perspectives on the metabolic management of epilepsy through dietary reduction of glucose and elevation of ketone bodies

Brain cells are metabolically flexible because they can derive energy from both glucose and ketone bodies (acetoacetate and beta-hydroxybutyrate). Metabolic control theory applies principles of bioenergetics and genome flexibility to the management of complex phenotypic traits. Epilepsy is a complex brain disorder involving excessive, synchronous, abnormal electrical firing patterns of neurons. We propose that many epilepsies with varied etiologies may ultimately involve disruptions of brain energy homeostasis and are potentially manageable through principles of metabolic control theory. This control involves moderate shifts in the availability of brain energy metabolites (glucose and ketone bodies) that alter energy metabolism through glycolysis and the tricarboxylic acid cycle, respectively. These shifts produce adjustments in gene-linked metabolic networks that manage or control the seizure disorder despite the continued presence of the inherited or acquired factors responsible for the epilepsy. This hypothesis is supported by information on the management of seizures with diets including fasting, the ketogenic diet and caloric restriction. A better understanding of the compensatory genetic and neurochemical networks of brain energy metabolism may produce novel antiepileptic therapies that are more effective and biologically friendly than those currently available.

The current treatment of epilepsy: a challenge of choices

There are now several distinct choices for seizure and epilepsy treatment. These include 16 antiepileptic medications, surgery, vagus nerve stimulation, and ketogenic diet. However, not every option is appropriate for all individuals with epilepsy. This article reviews the commonly employed treatments for chronic seizures, with the goal of trying to assess when certain treatments should be considered. An approach to seizure management is presented to help navigate the challenge of epilepsy treatment choices.

The ketogenic diet: adolescents can do it, too

PURPOSE

To determine both the efficacy of and compliance with the ketogenic diet in the adolescent population.

METHODS

A retrospective study of 45 patients, aged 12-19 years, consecutively enrolled in a ketogenic diet program from 1994 to 2002, was performed. Thirty-seven patients were from The Johns Hopkins Medical Institutions; eight were from The University of Texas at Houston. Charts were reviewed, and patients were contacted by telephone.

RESULTS

Six months after diet initiation, 28 (62%) of 45 remained on the ketogenic diet, with six (21%) of 28 having 50-90% seizure reduction, and eight (29%) of 28 having >90%. At 12 months, 20 (44%) of 45 remained on the diet, with seven (35%) of 20 having 50-90% seizure reduction and six (30%) of 20 achieving >90% efficacy. Only 22% discontinued the diet for perceived restrictiveness. The mean diet duration was 1.2 years. Patients with multiple seizure types did best, whereas gender, prior seizure frequency, diet ratio, and age did not influence outcome. Patients dependent on parents for daily care were more likely to remain on the diet at 6 months, but had less efficacy. Weight loss (60%) and menstrual dysfunction (45% of female subjects) were the most commonly reported side effects.

CONCLUSIONS

The ketogenic diet is as well tolerated and efficacious for adolescents with epilepsy as for the general childhood population.

The ketogenic diet for the treatment of epilepsy: a challenge for nutritional neuroscientists

The ketogenic diet (KD) is a high-fat, low-carbohydrate, adequate-protein diet that has been used for more than eight decades for the treatment of refractory epilepsy in children. Despite this long history, the mechanisms by which the KD exerts its anti-seizure action are not fully understood. Questions remain regarding several aspects of KD action, including its effects on brain biochemistry and energetics, neuronal membrane function and cellular network behavior. With the explosion of the KD use in the last 10 years, it is now imperative that we understand these factors in greater detail, in order to optimize the formulation, administration and fine-tuning of the diet. This review discusses what is known and what remains to be learned about the KD, with emphasis on clinical questions that can be approached in the laboratory. We encourage scientists with a primary interest in nutritional neuroscience to join with those of us in the epilepsy research community to address these urgent questions, for the benefit of children ravaged by intractable seizures.

[Ketogenic regime as anti-epileptic treatment: its use in 29 epileptic children]

INTRODUCTION

The ketogenic diet is a treatment option for patient with intractable or refractory epilepsy. It is a high-fat, low protein, low carbohydrate diet developed in 1920s. Recent research publications and media interest have renewed debate on the merits of ketogenic diet.

POPULATION

We report our experience with 29 children suffering from refractory epilepsy, treated with the ketogenic diet. No surgical option was available. Modalities are explained.

RESULTS

The ketogenic diet improved seizure control in 12/29 cases. It appeared effective in infants with infantile spasms. Refractory-status epilepticus responded to the ketogenic diet (3/6 cases). Migrating partial seizures in infancy were always refractory to the diet. Compliance with the diet was good. Adverse effects must be compared with the toxicity of antiepileptic drugs. One child had hypokaliemia with cardiac complication.

CONCLUSION

The ketogenic diet should be continued during one or 2 years when it is effective. It should be considered as an alternative therapy for children with refractory epilepsy.

Ketogenic diet for epilepsy

BACKGROUND

The ketogenic diet is a diet high in fat but low in carbohydrate and it is suggested that this diet reduces seizure frequency. Currently, this diet is used mainly for children who continue to have seizures despite treatment with antiepileptic drugs.

OBJECTIVES

To overview the evidence from randomized controlled trials regarding the effects of ketogenic diets.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group trials register (26 March 2003), the Cochrane Central Register of Controlled Trials (The Cochrane Library issue 1, 2003), MEDLINE (January 1966 to March 2003) and EMBASE (1980 to March 2003).

SELECTION CRITERIA

Randomized controlled trials of ketogenic diets for people with epilepsy.

DATA COLLECTION AND ANALYSIS

We planned for two reviewers to independently apply inclusion criteria and extract data.

MAIN RESULTS

No randomized controlled trials were found.

REVIEWER'S CONCLUSIONS

There is no reliable evidence from randomized controlled trials to support the use of ketogenic diets for people with epilepsy. There are large observational studies, some prospective, suggesting an effect on seizures. These effects need validating in randomized controlled trials. For those with a difficult epilepsy on multiple antiepileptic drugs, we consider the ketogenic diet a possible option.

Intractable pediatric epilepsy: vagal nerve stimulation and the ketogenic diet

The KD has been proven an effective alternative epilepsy treatment in children refractory to standard anticonvulsants. Children to be placed on the diet must be carefully selected, monitored, and followed. The diet is to be regarded as a strict medical regimen and requires a comprehensive medical team approach in concert with intensive parental involvement. With better understanding of the scientific principles underlying brain ketosis, we should be able to optimize the KD to achieve even better results.

1H and 31P spectroscopy and bioenergetics in the lateralization of seizures in temporal lobe epilepsy

Over the past decade, (1)H and (31)P spectroscopy measurements have demonstrated that significant metabolic alterations occur in temporal lobe epilepsy. However, to most accurately interpret these changes, metabolic heterogeneity and differences between gray and white matter must be accounted for. These alterations, decreased NAA and the ratio of phosphocreatine/inorganic phosphate, can be reversed with successful treatment of seizures. The reversibility of these two measures is consistent with the localization of NAA synthesis to neuronal mitochondria and the important role for bioenergetics in the pathophysiology of temporal lobe epilepsy.

Potential role of polyunsaturates in seizure protection achieved with the ketogenic diet

Epilepsy is a serious neurological disease that responds to two very different treatments involving lipids. Clinically, it responds to a state of ketosis induced by a very high-fat 'ketogenic' diet. Experimentally, in vitro and in vivo models demonstrate that injection or infusion of free (non-esterified) polyunsaturates such as arachidonate and docosahexaenoate also reduces seizure susceptibility. In our experience, rats on a very high-fat ketogenic diet not only have mild-to-moderate ketosis, but also have raised serum free fatty acids. Some polyunsaturates, particularly linoleate and alpha-linolenate, are relatively easily beta-oxidized and are therefore ketogenic. We conclude that raised levels of free plasma polyunsaturates could contribute to the beneficial effect of the ketogenic diet in refractory epilepsy not only by helping sustain ketosis, but also by their own direct (though poorly defined) antiseizure effects.

Status Epilepticus

Status epilepticus (SE) is a common neurologic emergency with a high mortality. Immediate recognition and rapid treatment are essential. After initial stabilization of airway and circulation, the patient should be treated as soon as possible with an intravenous (IV) benzodiazepine, followed immediately by IV fosphenytoin. If SE persists, general anesthesia should be initiated, with intubation and cardiac monitoring. Electroencephalogram must also be monitored to ensure suppression of all seizures. Etiology of SE should be assessed through history, examination, blood tests, and brain imaging.

Breath acetone is a reliable indicator of ketosis in adults consuming ketogenic meals

BACKGROUND

Ketogenic diets are used therapeutically to treat intractable seizures. Clinically, it appears that the maintenance of ketosis is crucial to the efficacy of the diet in ameliorating seizures. To understand how ketosis and seizure protection are related, a reliable, noninvasive measure of ketosis that can be performed frequently with minimal discomfort is needed.

OBJECTIVE

The objective was to determine which index, breath acetone or urinary acetoacetate, is more strongly related to the plasma ketones acetoacetate and beta-hydroxybutyrate.

DESIGN

After fasting overnight for 12 h, 12 healthy adults consumed 4 ketogenic meals over 12 h. Blood, breath, and urine samples were collected hourly. Blood was analyzed for plasma acetoacetate and beta-hydroxybutyrate, breath for acetone, and urine for acetoacetate.

RESULTS

By the end of the 12-h dietary treatment, plasma acetoacetate, plasma beta-hydroxybutyrate, and breath acetone had increased 3.5-fold, whereas urinary acetoacetate increased 13-fold when measured enzymatically and 25-fold when measured with urinary ketone dipsticks. Plasma acetoacetate was best predicted by breath acetone (R(2) = 0.70, P < 0.0001). Plasma beta-hydroxybutyrate was equally predicted by breath acetone and urinary acetoacetate (R(2) = 0.54, P = 0.0040).

CONCLUSIONS

Breath acetone is as good a predictor of ketosis as is urinary acetoacetate. Breath acetone analysis is noninvasive and can be performed frequently with minimal discomfort to patients. As an indicator of ketosis in epilepsy patients consuming a ketogenic diet, breath acetone may be useful for understanding the mechanism of the diet, elucidating the importance of ketosis in seizure protection, and ultimately, enhancing the efficacy of the diet by improving patient monitoring.

The ketogenic diet may have mood-stabilizing properties

The ketogenic diet, originally introduced in the 1920s, has been undergoing a recent resurgence as an adjunctive treatment for refractory epilepsy, particularly in children. In this difficult-to-treat population, the diet exhibits remarkable efficacy with two-thirds showing significant reduction in seizure frequency and one-third becoming nearly seizure-free. There are several reasons to suspect that the ketogenic diet may also have utility as a mood stabilizer in bipolar illness. These include the observation that several anticonvulsant interventions may improve outcome in mood disorders. Furthermore, beneficial changes in brain-energy profile are noted in subjects on the ketogenic diet. This is important since global cerebral hypometabolism is a characteristic of the brains of depressed or manic individuals. Finally, the extracellular changes that occur in ketosis would be expected to decrease intracellular sodium concentrations, a common property of all effective mood stabilizers. Trials of the ketogenic diet in relapse prevention of bipolar mood episodes are warranted.

Efficacy of the ketogenic diet in focal versus generalized seizures

Most reports of the ketogenic diet have focused on its efficacy for generalized seizures. Few data are available regarding its effect on focal seizures. We retrospectively studied patients (mean = 7.5 years of age) with medically intractable epilepsy treated by the ketogenic diet. The predominant seizure types in each patient were classified as generalized (100 patients) or focal (34 patients) based on ictal electroencephalograms (EEGs) or seizure semiology and interictal EEG. A seizure reduction of more than 50% compared with baseline was seen in nine patients (27%) with focal seizures and 46 patients (46%) with generalized seizures at 3 months, in 10 patients (30%) with focal seizures and 46 patients (46%) with generalized seizures at 6 months, and in eight patients (24%) with focal seizures and 42 patients (42%) with generalized seizures at 12 months. Differences were not significant. Outcome tended to be better in patients younger than 12 years of age compared with the older age group, but the difference was significant at 6 months only. Our results suggest that some patients with intractable focal epilepsy may respond favorably to the ketogenic diet and that this option should be considered if epilepsy surgery is not possible.

The difference in perceptions of educational need between epilepsy patients and medical personnel

PURPOSE

This study was undertaken to determine what patients with epilepsy need to know about their condition, and to discern what differences exist between patients' perceptions of this need and the medical profession's perception of what patients should know.

METHODS

Seventy-five consecutive patients with epilepsy and 56 medical personnel (residents and nurses) who were working in either Neurology or Neurosurgery Units were studied using a structured questionnaire consisting of 3 subsets with a total of 27 questions.

RESULTS

Using a Likert scale, epilepsy patients gave high priority to their need for more information about "how epilepsy is diagnosed," "the structure of the brain" (p < 0.05, p < 0.01, respectively), and "the diet that might prevent the attack" (p < 0.05) than did medical personnel. Our study also revealed that men were more concerned with questions regarding smoking and drinking than were women (p < 0.05, respectively), whereas married patients gave higher scores in the category of employment (p < 0.01) and contraception/pregnancy (p < 0.05) than did unmarried patients. The patients with one or more seizures per month rated higher scores on questions concerning the first aid at the time of attack and dosage of antiepileptic drugs (AEDs; p < 0.05, respectively) than did the patients with fewer than one seizure per month. The patients taking poly-AED treatment gave higher scores on six items related to AED therapy than did those receiving monotherapy. No significant differences were found with regard to the length of time patients had the condition, nor to educational level or current employment status.

CONCLUSIONS

An educational program for epilepsy patients should be developed on the basis of understanding that there are differences in perspectives among patients with different sociocultural contexts as well as between patients and medical personnel.

Vagus nerve stimulation and the ketogenic diet

Antiepileptic drugs are the primary form of treatment for patients with epilepsy. In the United States, hundreds of thousands of people do not achieve seizure control, or have significant side effects, or both. Only a minority of patients with intractable epilepsy are candidates for traditional epilepsy surgery. Vagus nerve stimulation is now the second most common treatment for epilepsy in the United States. Additionally, the ketogenic diet has established itself as a valid treatment. This article discusses the history, mechanism of action, patient selection, efficacy, initiation, complications, and advantages of vagus nerve stimulation and the ketogenic diet.

Lipid and fatty acid profiles in rats consuming different high-fat ketogenic diets

High-fat ketogenic diets are used to treat intractable seizures in children, but little is known of the mechanism by which these diets work or whether fats rich in n-3 polyunsaturates might be beneficial. Tissue lipid and fatty acid profiles were determined in rats consuming very high fat (80 weight%), low-carbohydrate ketogenic diets containing either medium-chain triglyceride, flaxseed oil, butter, or an equal combination of these three fat sources. Ketogenic diets containing butter markedly raised liver triglyceride but had no effect on plasma cholesterol. Unlike the other fats, flaxseed oil in the ketogenic diet did not raise brain cholesterol. Brain total and free fatty acid profiles remained similar in all groups, but there was an increase in the proportion of arachidonate in brain total lipids in the medium-chain triglyceride group, while the two groups consuming flaxseed oil had significantly lower arachidonate in brain, liver, and plasma. The very high dietary intake of alpha-linolenate in the flaxseed group did not change docosahexaenoate levels in the brain. Our previous report based on these diets showed that although ketosis is higher in rats consuming a ketogenic diet based on medium-chain triglyceride oil, seizure resistance in the pentylenetetrazol model is not clearly related to the degree of ketosis achieved. In combination with our present data from the same seizure study, it appears that ketogenic diets with widely differing effects on tissue lipids and fatty acid profiles can confer a similar amount of seizure protection.

Timing of ketogenic diet initiation in an experimental epilepsy model

Following kainic acid (KA)-induced status epilepticus (SE), the ketogenic diet (KD) retards the development of epileptogenesis, with fewer spontaneous recurrent seizures (SRS) and less mossy fiber sprouting than rats on a normal diet. In this study, we investigated whether there is a critical period for initiation of the KD, in terms of the diet's effectiveness in reducing SRS. In addition, we investigated whether early treatment with the KD prevents the deficits in spatial learning and memory that ordinarily follow KA-induced SE. Young rats (P30) underwent KA-induced SE, followed by assignment to one of three treatment groups: control diet ('KA'), KD begun 2 days after SE ('KD2'), and KD begun fourteen days after SE ('KD14'). For 12 weeks following SE, rats were monitored by closed circuit video recording (12 h/wk) to detect SRS. KD2 rats had significantly fewer SRS than rats in the control or KD14 groups. On water maze testing to assess spatial learning and memory, KD2 rats had significantly poorer acquisition of place learning than control (KA alone) or KD14 rats. KD2 rats also failed to gain weight well. There was no difference between groups on routine histologic examination of the hippocampus. In summary, P30 rats placed on the KD 2 days after SE were relatively protected from recurrent seizures, but showed behavioral and physical impairment. Rats placed on the KD 14 days after KA-induced SE did not differ from controls with regard to spontaneous seizure rate.

Epilepsy and Cortical Dysplasias

Focal cortical dysplasias (FCD) and diffuse cortical dysplasias (DCD) are a heterogeneous group of disorders defined by abnormal cerebral cortical cytoarchitecture that are associated with epilepsy. Patients with either DCD or FCD may suffer from a variety of epilepsy subtypes and these are often refractory to most anti-epileptic drugs (AEDs) despite polytherapy. The etiologies of cortical dysplasias (CD) are diverse, and include inherited genetic syndromes such as Miller-Dieker or X-linked lissencephaly, subcortical band heterotopia, and the tuberous sclerosis complex, as well as nongenetic exogenous insults such as hypoxic-ischemic injury, viral or other type of central nervous system infection, or traumatic injury. A large number of FCD cases are idiopathic and very small regions of FCD (microdysgenesis) are now being identified in resected epilepsy specimens. Recent data suggests that nearly 30% of epilepsy specimens evaluated histologically will contain regions of overt or microscopic CD. The mainstay of appropriate therapy for CD remains the standard AEDs or epilepsy surgery. In too few disorders, specific AEDs provide therapeutic advantage in the setting of individual forms of CD. The ketogenic diet may provide seizure control in a subpopulation of patients. In both DCD and FCD, surgical resection can be curative in the appropriately selected patients. Surgical approaches include focal neocortical resections, temporal lobectomy, or larger hemispheric resection procedures.