Therapeutic Ketogenic Diet in Partial Hospital Program (PHP) Anorexia Nervosa

This will be a 14-week longitudinal study with an open design. A total of 120 individuals will be recruited for an end goal of 60 individuals with anorexia nervosa (AN) who are currently in high level of care treatment at the UCSD Eating Disorder Center partial hospital program (PHP) or intensive outpatient (IOP). Forty individuals will be recruited to the TKD and 20 will be treated with treatment as usual with respect to food intake. The age range will be between 16 and 45 years. All study participants will be carefully assessed and will complete rater and self-assessments at the being at the end of the study period. While in the treatment program, the TKD group will receive catered ketogenic meals via a meal service. After discharging from program, participants will have the option to continue with the meal service or cook for themselves. After establishing ketosis, study participants will continue TKD for 12 weeks. All study participants will be followed over three, six, and twelve months after enrolling in the study, whether initiating TKD or being in the treatment as usual arm. This follow-up procedure will help determine whether symptom improvement is stable or worsens in individuals who choose to continue or discontinue the TKD intervention and in relation to the control group. After ketosis induction over two weeks, study participants will be assessed weekly for ketosis and mood, anxiety, and eating disorder symptoms over twelve weeks.

For this 14-week study, 60 individuals with anorexia nervosa (AN) who are currently in high level of care treatment at the UC San Diego Health Eating Disorders Center for Treatment and Research (UC San Diego Health EDC) partial hospitalization program (PHP) or IOP will be recruited. These individuals will be underweight or recently weight-restored and continue to have high impairment from the illness as indicated by an Eating Disorder Examination Questionnaire (EDE-Q) global score greater than 2.09.

Of those 60 participants, 40 of them will participate in the Therapeutic Ketogenic Diet (TKD) Study Arm and 20 subjects will be enrolled in the Treatment as Usual Study Arm. The study will be conducted in a university medical environment, showing feasibility and safety in a typical medical setting.

After completing the screening steps all participants will complete a blood draw and genetics testing.

AN subjects will be given the option to participate in the TKD Study Arm or the Treatment as Usual Study Arm. Recruitment in each arm will continue until the end recruitment enrollment goal for each arm has been reached. Subjects will not be randomized to the study arm and will be given a choice of what arm they want to participate in. Subjects who consent to be in the TKD Study Arm will complete 14 weeks of therapeutic ketogenic diet (TKD), weekly weight and ketone measurements, weekly behavioral assessments, and meetings with the study doctor and dietician every week, and peer counseling sessions. While in the treatment program, the TKD group will receive catered ketogenic meals via a meal service. After discharging from program, participants will have the option to continue with the meal service or cook for themselves.

AN subjects who consent to be in the Treatment as Usual Study Arm will complete weekly weight and ketone measurements and questionnaires for 14 weeks.

After discharge from the PHP program, subjects will continue to be monitored virtually for the study procedures.

In the last week of the therapeutic ketogenic diet (week 14), all AN subjects will complete another blood draw and the exit visit with the study doctor and dietician.

AN subjects will complete follow-up visits 3 months, 6 months, and 1 year after the 14-week completion date.

Eligibility Criteria:
Inclusion Criteria:

1. Provision of signed and dated informed consent form/parental permission form
2. Provision of signed and dated assent form if the subject is a minor
3. Stated willingness to comply with all study procedures and availability for the duration of the study
4. Persons, aged 16 to 45 years
5. Current anorexia nervosa diagnosis according to DSM-5 criteria
6. An elevated EDE-Q global score of 2.09 or greater
7. The following types of psychiatric medications are allowed: antidepressant, anxiolytic, atypical antipsychotic, mood stabilizers
8. English is primary spoken language

Exclusion Criteria:

1. Pregnancy or lactation
2. Electrolyte, blood count, kidney function or liver function abnormalities
3. Psychosis
4. Neurocognitive disorders including dementias or traumatic brain injury that is symptomatic
5. Current alcohol use disorder (AUD) or substance use disorder (SUD) according to DSM-5 criteria
6. Uncontrolled hypertension
7. Hepatic impairment (Class-Pugh b or c)
8. Diabetes mellitus
9. Family history of porphyria
10. History of recent heart attack, vascular disease, or any other current acute medical conditions as determined by the principal investigator
11. Inability or unwillingness to adhere to the TKD diet for the duration of the study
12. Blind or illiterate individuals