Energy Expenditure and Quality of Life in Epilepsy

The main objectives of this study are to investigate the influence of the ketogenic diet (KD), standard care for patients assisted in the UW Health Adult Epilepsy Dietary Therapy Clinic, on changes in the frequency and severity of seizures, QoL, energy substrate metabolism, body energy expenditure components, fat mass and fat-free mass in adults with epilepsy. To achieve this objective, twenty-five male and female participants between the ages of 18 and 45 years (or over 18 years for remote participation), who accepted to initiate the KD as a standard of care prescribed by their physician, will be recruited according to inclusion/exclusion criteria. Participants will be on study for 6 months.

The ketogenic diet (KD) is a high fat, very low carbohydrate diet that promotes a variety of changes in the chemical processes on the body associated with reduced frequency and severity of seizures in patients with epilepsy. The reasons for this improvement are not yet fully understood and the answers can be related to changes in the biochemical process and the use of different substrates as the main source of energy for the body.

The quality of life (QoL) of patients with epilepsy is highly affected by stigmatization, difficulties with employment, and physical limitations. There is some evidence that the KD may have beneficial effects on QoL in patients with epilepsy, which can be investigated by changes in body energy expenditure (e.g. physical activity level). Studies that associate changes in body energy requirements, body composition and biochemical measures with seizures and QoL are currently limited in the scientific literature.

The main objectives of this study are to investigate the influence of the KD on changes in the frequency and severity of seizures, QoL, energy substrate metabolism, body energy expenditure components, fat mass and fat-free mass in adults with epilepsy. To achieve this objective, twenty-five male and female participants between the ages of 18 and 45 years (or over 18 years old for remote participation, no metabolic analysis will be complete on remote participants) will be recruited according to inclusion/exclusion criteria. Data will be collected at baseline (time of enrollment), and again at 3 and 6 months following diet start. Stable isotope compounds (doubly labeled water) will assess total daily energy expenditure (TDEE) and body composition (fat mass; fat-free mass). Indirect calorimetry will assess the resting energy expenditure (REE) and respiratory quotient for energy substrate oxidation. Biochemical blood exams (fasting glucose and insulin, and ketone bodies) and anthropometric data will provide data on the nutritional and metabolic status of the participant. Seizure frequency, severity, and QoL will be evaluated using validated self-report questionnaires. The physical activity level, obtained through the ratio between TDEE and REE and by wearing of a physical activity monitor, will be used as a predictor of QoL.

The hypothesis is that KD therapy promotes differences in energy metabolism and energy substrate oxidation, which will lead to better metabolic control of epilepsy, reduced frequency and severity of seizures, and also an improved patient QoL. This study is expected to help elucidate the metabolic changes associated with reduced seizure frequency and severity, and improvement of QoL in patients with epilepsy.

Eligibility Criteria:
Inclusion Criteria (in person participation):

* aged 18-45
* Diagnosis of epilepsy
* Experience an average of 2 or more seizures per month during the 3 months prior to study
* Plan to start oral ketogenic diet therapy (e.g. with the modified Atkins diet)
* Have low average or higher cognitive/intellectual function and are able to complete self-report questionnaires

Inclusion Criteria for Remote Participation:

* over 18 years of age (no age limit)
* Diagnosis of epilepsy
* Experience an average of 2 or more seizures per month during the 3 months prior to study
* Plan to start oral ketogenic diet therapy (e.g. with the modified Atkins diet)
* Have low average or higher cognitive/intellectual function and are able to complete self-report questionnaires

Exclusion Criteria:

* Participants who report being claustrophobic
* Presence of edema, conditions or persistent side effects of medication use (e.g. vomiting, diarrhea, excessive sweating, and burns) that could cause alterations in the body hydration and consequently, be a bias in energy metabolism variables
* Currently using medications that may cause metabolic and/or absorptive alterations (e.g. diuretics, amphetamines, lipase inhibitors, corticosteroids, etc.)
* Unstable metabolic condition (e.g. persistent sodium \<130 or glucose \<50)
* Liver, kidney, or pancreatic disease
* Hypercholesterolemia (cholesterol \> 300mg/dL)
* Currently pregnant or planning on becoming pregnant
* Fatty acid oxidation disorder or pyruvate carboxylase deficiency
* Already on ketogenic therapy