Use of the ketogenic diet and dietary practices in the UK

Insights into the Cellular Interactions and Molecular Mechanisms of Ketogenic Diet for Comprehensive Management of Epilepsy

A high-fat diet with appropriate protein and low carbohydrate content, widely known as the ketogenic diet (KD), is considered as an effective non-pharmacotherapeutic treatment option for certain types of epilepsies. Several preclinical and clinical studies have been carried out to elucidate its mechanism of antiepileptic action. Ketone bodies produced after KD's breakdown interact with cellular excito-inhibitory processes and inhibit abnormal neuronal firing. The generated ketone bodies decrease glutamate release by inhibiting the vesicular glutamate transporter 1 and alter the transmembrane potential by hyperpolarization. Apart from their effect on the well-known pathogenic mechanisms of epilepsy, some recent studies have shown the interaction of KD metabolites with novel neuronal targets, particularly adenosine receptors, adenosine triphosphate-sensitive potassium channel, mammalian target of rapamycin, histone deacetylase, hydroxycarboxylic acid receptors, and the NLR family pyrin domain containing 3 inflammasomes to suppress seizures. The role of KD in augmenting gut microbiota as a potential mechanism for epileptic seizure suppression has been established. Furthermore, some recent findings also support the beneficial effect of KD against epilepsy- associated comorbidities. Despite several advantages of the KD in epilepsy management, its use is also associated with a wide range of side effects. Hypoglycemia, excessive ketosis, acidosis, renal stones, cardiomyopathies, and other metabolic disturbances are the primary adverse effects observed with the use of KD. However, in some recent studies, modified KD has been tested with lesser side effects and better tolerability. The present review discusses the molecular mechanism of KD and its role in managing epilepsy and its associated comorbidities.

K.Vita: a feasibility study of a blend of medium chain triglycerides to manage drug-resistant epilepsy

This prospective open-label feasibility study aimed to evaluate acceptability, tolerability and compliance with dietary intervention with K.Vita, a medical food containing a unique ratio of decanoic acid to octanoic acid, in individuals with drug-resistant epilepsy. Adults and children aged 3-18 years with drug-resistant epilepsy took K.Vita daily whilst limiting high-refined sugar food and beverages. K.Vita was introduced incrementally with the aim of achieving ≤35% energy requirements for children or 240 ml for adults. Primary outcome measures were assessed by study completion, participant diary, acceptability questionnaire and K.Vita intake. Reduction in seizures or paroxysmal events was a secondary outcome. 23/35 (66%) children and 18/26 (69%) adults completed the study; completion rates were higher when K.Vita was introduced more gradually. Gastrointestinal disturbances were the primary reason for discontinuation, but symptoms were similar to those reported from ketogenic diets and incidence decreased over time. At least three-quarters of participants/caregivers reported favourably on sensory attributes of K.Vita, such as taste, texture and appearance, and ease of use. Adults achieved a median intake of 240 ml K.Vita, and children 120 ml (19% daily energy). Three children and one adult had ß-hydroxybutyrate >1 mmol/l. There was 50% (95% CI 39-61%) reduction in mean frequency of seizures/events. Reduction in seizures or paroxysmal events correlated significantly with blood concentrations of medium chain fatty acids (C10 and C8) but not ß-hydroxybutyrate. K.Vita was well accepted and tolerated. Side effects were mild and resolved with dietetic support. Individuals who completed the study complied with K.Vita and additional dietary modifications. Dietary intervention had a beneficial effect on frequency of seizures or paroxysmal events, despite absent or very low levels of ketosis. We suggest that K.Vita may be valuable to those with drug-resistant epilepsy, particularly those who cannot tolerate or do not have access to ketogenic diets, and may allow for more liberal dietary intake compared to ketogenic diets, with mechanisms of action perhaps unrelated to ketosis. Further studies of effectiveness of K.Vita are warranted.

Keto-on-the-Clock: A Survey of Dietetic Care Contact Time Taken to Provide Ketogenic Diets for Drug-Resistant Epilepsy in the UK

Medical ketogenic diets (KDs) are effective yet resource-intensive treatment options for drug-resistant epilepsy (DRE). We investigated dietetic care contact time, as no recent data exist. An online survey was circulated to ketogenic dietitians in the UK and Ireland. Data were collected considering feeding route, KD variant and type of ketogenic enteral feed (KEF), and the estimated number of hours spent on patient-related activities during the patient journey. Fifteen dietitians representing nine KD centres responded. Of 335 patients, 267 (80%) were 18 years old or under. Dietitians spent a median of 162 h (IQR 54) of care contact time per patient of which a median of 48% (IQR 6) was direct contact. Most time was required for the classical KD taken orally (median 193 h; IQR 213) as a combined tube and oral intake (median 211 h; IQR 172) or a blended food KEF (median 189 h; IQR 148). Care contact time per month was higher for all KDs during the three-month initial trial compared to the two-year follow-up stage. Patients and caregivers with characteristics such as learning or language difficulties were identified as taking longer. Twelve out of fifteen (80%) respondents managed patients following the KD for more than two years, requiring an estimated median contact care time of 2 h (IQR 2) per patient per month. Ten out of fifteen (67%) reported insufficient official hours for dietetic activities. Our small survey gives insight into estimated dietetic care contact time, with potential application for KD provision and service delivery

Assessing the role of ketogenic dietary therapy in ring chromosome 20 syndrome: A patient-led approach

Ring chromosome 20 syndrome (r(20)) is an ultra‐rare disease characterized by drug‐refractory epilepsy, cognitive impairment, and behavioral problems. Nonpharmacological treatments alongside antiepileptic drugs early after diagnosis may help reduce seizure frequency and preserve cognition. Ketogenic dietary therapy (KDT) has benefitted children with complex, refractory epilepsies, but its efficacy in r(20) is unknown. We assessed clinical prescription, implementation, and patient experience of KDT in r(20) through online surveys and a workshop. Forty‐two patients, families, carers, and 23 healthcare professionals completed the surveys. While nearly all patients were familiar with KDT, only half had tried it. Significant improvement in seizure activity, cognition, and alertness was reported; side effects were typically mild but with one report of increased seizure frequency. A high rate of co‐morbidity, older age at presentation, behavioral problems, and cognitive impairment can make implementing KDT in r(20) challenging. In the UK, NHS KDT services are predominantly available to pediatric patients, with very limited adult access. A health economic analysis illustrating reduced acute care costs or improved quality of life may support more widespread KDT implementation. Growing evidence supports KDT as an effective and safe intervention, but further research is needed to understand the mechanisms of r(20) and its interaction with ketosis.

Nice to know: impact of NICE guidelines on ketogenic diet services nationwide

BACKGROUND

In 2012, the National Institute for Health and Care Excellence (NICE) Clinical Guidelines for Epilepsies: Diagnosis and Management (CG137) included, for the first time, ketogenic diets (KDs) as a treatment option for drug-resistant paediatric epilepsy. The recommendation was made to refer children and young people with epilepsy whose seizures have not responded to appropriate anti-epileptic drugs to a tertiary paediatric epilepsy specialist for consideration of the use of KDs. We aimed to assess the impact of this change in guidance on the numbers of ketogenic centres and patients following KDs for epilepsy in the UK and Ireland.

METHODS

An online survey was circulated to ketogenic dietitians from the UK and Ireland. The results were compared with similar surveys published in 2000 and 2010.

RESULTS

The number of centres offering KDs for treatment of epilepsy has risen from 22 in 2000, to 28 in 2010, and to 39 in 2017 (77% overall increase). Seven of these centres accept adult referrals, in comparison to only two centres in 2010. Patient numbers have increased from 101 in 2000 to 754 in 2017. In total, 267 patients are waiting to commence KD at 31 centres.

CONCLUSIONS

Over the last 7 years, the number of patients treated with a KD for epilepsy in the UK and Ireland has increased by 647%, with a 77% increase in the number of centres offering KDs. Despite this rapid growth, there is ongoing demand for patients to be considered for dietary therapy, highlighting the need for continued expansion of KD services nationally.

Evaluation of the Utility of a Dietary Therapy Second Opinion Clinic

Fine-tuning ketogenic diets to achieve better seizure control may influence families to seek second opinions. Since 2009, Johns Hopkins Hospital has provided second opinions for children followed at other ketogenic diet centers. We retrospectively reviewed 65 consecutive children seen in this clinic; parents were also sent a 2-page survey. The mean age was 6.6 years and dietary therapy had been used a median 9 months. Seizure reduction >50% was achieved in 65%, including 35% with >90% reduction. Parent questions included how to improve seizure control (65%), ideal diet duration (18%), and confirmation of the plan (11%). The most common recommendations were anticonvulsant reduction (43%), adding oral citrates/calcium/vitamins (38%), and carnitine supplementation (31%). Diet discontinuation was more frequently suggested in those children with <50% seizure reduction (60% vs 20%, P = .001). Recommendations were successful in 78%, and the visit was reported as useful by 88%.

Ketogenic diet for treatment of intractable epilepsy in adults: A meta-analysis of observational studies

The ketogenic diet (KD) is an effective treatment for children with drug-resistant epilepsy and has been widely used in young children. Adult patients with intractable epilepsy would also benefit from this dietary treatment. However, only a few studies have been published, and the use of the KD in intractable epilepsy in adults has been limited. This meta-analysis summarized the findings of the relevant published studies to identify the efficacy of the KD for the treatment of intractable epilepsy in adults. In this meta-analysis, PubMed, Embase, and Cochrane Library were used for searching studies concerning the effects of the KD and its major subtypes with intractable epilepsy in adults published up to January 10, 2017. The primary outcomes were seizure freedom, seizure reduction by 50% or more, and seizure reduction by <50%. The quality of the methodology of the observational studies was reviewed by using the Newcastle-Ottawa Scale. We identified 402 articles, of which, 16 studies including 338 patients met the inclusion criteria. The results of the meta-analysis showed that the combined efficacy rates of all the symptoms of seizure freedom, seizure reduction by 50% or more, and seizure reduction below 50% in adults with intractable epilepsy were 13%, 53%, and 27%, respectively. The adverse reactions of the KD were mild, whereas low glycemic index diet (LGID) and low-dose fish oil diet (LFOD) may have fewer side effects. Weight loss, high level of low-density lipoprotein, and elevated total cholesterol were most frequent. The meta-analysis indicates that the KD for refractory epilepsy in adults is a well-tolerated treatment and that its side effects are acceptable, which show that the KD is a promising treatment in adult intractable epilepsy. Further research is needed to assess which type of diet or ratio is more effective in the KD treatment.

Impact of Child Life Services on Children and Families Admitted to Start the Ketogenic Diet

Traditionally the ketogenic diet is started as an inpatient admission to the hospital. Starting in January 2015, child life services were made formally available during ketogenic diet admissions to help families cope. One-page surveys were then provided to 15 parents on the day of discharge and again after 3 months. Every family believed that the child life services were helpful. Children who were developmentally appropriate/mildly delayed had higher parent-reported anxiety scores than those who were moderate to severely delayed (4.4 vs 1.0, P = .02). At 3 months, child life services were deemed very helpful for the parents (mean score: 8.9, range: 5-10), and were more helpful for the parent than the child (mean 6.2, range 1-10, P = .047). One of the most helpful services was a prior phone call to parents 1 week prior. In this small pilot study, child life involvement during the start of the ketogenic diet was highly useful.

Complications During Ketogenic Diet Initiation: Prevalence, Treatment, and Influence on Seizure Outcomes

BACKGROUND

Many centers still admit children for several days to start the ketogenic diet. The exact incidence of adverse effects during the admission and their potential later impact on seizure reduction has not been widely studied.

METHODS

We performed a retrospective study of children with intractable epilepsy electively admitted for ketogenic diet initiation at our institution from 2011 to 2016. Charts were reviewed for adverse effects during the admission period and then examined for seizure reduction and compliance at three months. A rating scale (1 to 4) was created for severity of any adverse events.

RESULTS

A total of 158 children were included, with the mean age 4.6 years. Potentially attributable adverse effects occurred in 126 (80%) children, most commonly emesis, food refusal, and hypoglycemia. Seventy-three (46%) children received some form of intervention by the medical team, most commonly the administration of juice (24%). Younger age was correlated with an increased likelihood of moderate to severe adverse effects during admission, often repeated hypoglycemia (3.6 versus 4.9 years, P = 0.04). Fasting was more likely to result in lethargy and a single blood glucose in the 30 to 40 mg/dL range, but it was not correlated with emesis, repeated hypoglycemia, or higher adverse effect scores. There was no statistically significant correlation between the severity of adverse effects and the three-month seizure reduction.

CONCLUSIONS

Mild easily treated adverse effects occurred in most children admitted for the ketogenic diet. Younger children were at greater risk for significant difficulties and should be monitored closely. Because fasting led to more lethargy and hypoglycemia, it may be prudent to avoid this in younger children.

The changing face of dietary therapy for epilepsy

Ketogenic diet is an established and effective non-pharmacologic treatment for drug-resistant epilepsy. Ketogenic diet represents the treatment of choice for GLUT-1 deficiency syndrome and pyruvate dehydrogenase complex deficiency. Infantile spasms, Dravet syndrome and myoclonic-astatic epilepsy are epilepsy syndromes for which ketogenic diet should be considered early in the therapeutic pathway. Recently, clinical indications for ketogenic diet have been increasing, as there is emerging evidence regarding safety and effectiveness. Specifically, ketogenic diet response has been investigated in refractory status epilepticus and encephalopathy with status epilepticus during sleep. New targets in neuropharmacology, such as mitochondrial permeability transition, are being studied and might lead to using it effectively in other neurological diseases. But, inefficient connectivity and impaired ketogenic diet proposal limit ideal availability of this therapeutic option. Ketogenic diet in Italy is not yet considered as standard of care, not even as a therapeutic option for many child neurologists and epileptologists.

CONCLUSIONS

The aim of this review is to revisit ketogenic diet effectiveness and safety in order to highlight its importance in drug-resistant epilepsy and other neurological disorders.

WHAT IS KNOWN

• Ketogenic diet efficacy is now described in large case series, with adequate diet compliance and side effects control. • Ketogenic diet is far from being attempted as a first line therapy. Its availability varies worldwide. What is New: • New pharmacological targets such as mitochondrial permeability transition and new epileptic syndromes and etiologies responding to the diet such as refractory status epilepticus are being pointed out. • Ketogenic diet can function at its best when used as a tailor-made therapy. Fine tuning is crucial.

Diet and identity: being a good parent in the face of contradictions presented by the ketogenic diet

The ketogenic diet is a high-fat diet used to treat drug-resistant childhood epilepsy. Given that negative meanings tend to be attached to fatty foods and children's food consumption is seen to be the responsibility of parents, the ketogenic diet may be problematic for parenting identity. This article draws upon in-depth semi-structured interviews with 12 parents from 10 families that have a child whose epilepsy is being treated with the ketogenic diet. The main focus of the article is the meanings these parents attached to foods and how they were drawn upon or altered to overcome some of the contradictions presented by the diet. It will be argued that the diet was medicalised and parents came to view food as medicine. When viewing food in this way, negative associations with fat were reversed. Furthermore, parents also used food as a symbol of inclusion and prioritised portion size or the child's enjoyment of food in order to use food as a symbol of love. In turn this enabled parents to feel they were being good parents. Overall, it seems that diet can be medicalised and the identity of the good parent maintained if dietary treatment is successful.

What are the minimum requirements for ketogenic diet services in resource-limited regions? Recommendations from the International League Against Epilepsy Task Force for Dietary Therapy

Despite the increasing use of dietary therapies for children and adults with refractory epilepsy, the availability of these treatments in developing countries with limited resources remains suboptimal. One possible contributory factor may be the costs. There is often reported a significant perceived need for a large ketogenic diet team, supplements, laboratory studies, and follow-up visits to provide this treatment. The 2009 Epilepsia Consensus Statement described ideal requirements for a ketogenic diet center, but in some situations this is not feasible. As a result, the International League Against Epilepsy (ILAE) Task Force on Dietary Therapy was asked to convene and provide practical, cost-effective recommendations for new ketogenic diet centers in resource-limited regions of the world.

Effects of the ketogenic diet on nutritional status, resting energy expenditure, and substrate oxidation in patients with medically refractory epilepsy: a 6-month prospective observational study

BACKGROUND & AIMS

This 6-month prospective, single-arm observational study was designed to assess the effects of the KD on the nutritional status, resting energy expenditure (REE), and substrate oxidation in patients with drug-resistant epilepsy.

METHODS

Eighteen patients with medically refractory epilepsy underwent assessment of body composition, REE, and substrate oxidation rates before and after 6 months of KD.

RESULTS

Compared with baseline, there were no statistically significant differences at 6 months in terms of height, weight, BMI z-scores, and REE. However, the respiratory quotient decreased significantly (from 0.80 ± 0.06 to 0.72 ± 0.05, p < 0.001) whereas fat oxidation was significantly increased (from 50.9 ± 25.2 mg/min to 97.5 ± 25.7 mg/min, p < 0.001). Interestingly, we found that the increase in fat oxidation was the main independent predictor of the reduction in seizure frequency (beta = -0.97, t = -6.3, p < 0.05).

CONCLUSIONS

Administering a KD for 6 months in patients with medically refractory epilepsy increases fat oxidation and decreases the respiratory quotient, without appreciable changes in REE.