Individualized Study of Refeeding to Optimize iNpatient Gains (i-STRONG)

Stanford University, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

The primary purpose of the trial is to compare the efficacy and safety of Individualized Caloric Refeeding (ICR) to the new standard of care, Higher Calorie Refeeding (HCR), in hospitalized patients with atypical anorexia nervosa (AAN), and clinical remission over one year of follow-up.

Atypical Anorexia Nervosa (AAN) is a new diagnosis describing patients with malnutrition and significant weight loss yet "normal" weight. These patients responded poorly to HCR, the superior refeeding treatment in the parent trial, which was designed for low-weight patients with typical AN. The proposed trial will examine the safety and efficacy of a new treatment for AAN with the potential to improve treatment outcomes for this diverse and growing patient population. The major finding motivating the proposed trial is that participants with AAN gained weight 40 percent slower and required 3.0 additional days in hospital to restore medical stability on HCR, as compared to AN. The research team has developed Individualized Caloric Refeeding (ICR), which doses calories to weight consistent with other pediatric treatments (e.g. medication). The primary purpose of the proposed trial is to compare the efficacy and safety of ICR to the new standard of care (HCR) in hospitalized patients with AAN. The investigators hypothesize that ICR will restore medical stability faster than HCR with no increase in electrolyte abnormalities. After hospitalization, the major barrier to care in AAN is lack of consensus on clinical remission and whether these formerly overweight patients should gain weight to recover. The research team will examine metabolic, hormonal and psychological markers during long-term follow-up, toward the goal of developing a definition of clinical remission in AAN. Design Summary: Randomized controlled trial in N=74 participants age 12-24 with AAN, consented upon hospital admission, randomly assigned to ICR or HCR, followed daily in hospital and at 3, 6, 9 and 12 mo.

Participants will be recruited upon hospital admission at the University of California, San Francisco (UCSF) and Stanford and randomly assigned to Individualized Caloric Refeeding (ICR) or Higher Calorie Refeeding (HCR) for the duration of the hospitalization. Treatment ends at hospital discharge with open follow-up for one year. Participants followed daily in hospital and at 3mo, 6mo, 9mo, and 12mo post-discharge.

Treatments are not to be blinded, since both the patients and clinicians who work with this population are highly skilled at estimating kcal and would be able to determine group assignment by simply viewing meal trays.

Meal-based refeeding in hospital, starting at 50 calories per kilogram of body weight, and increasing by 200 calories per day until caloric goal achieved

Meal-based refeeding in hospital, starting at 2000 calories per day, and increasing by 200 calories per day until caloric goal achieved

Medical stability will be adjudicated by a five-point index: (1) 24 hour heart rate of 45 beats/min or more, (2) systolic blood pressure of 90 millimeters of mercury (mmHg) or more, (3) temperature of 35.6° C or more, (4) orthostatic increase in heart rate of 35 beats/min or less, (5) orthostatic change in systolic blood pressure of 20 mmHg or less.

Incidence of low electrolytes will be defined as: (1) hypophosphatemia less than 3 milligrams per deciliter (mg/dL), (2) hypomagnesaemia less than 1.8 mg/dL, and (3) hypokalemia less than 3.5 milliequivalent per liter (mEq/L) during hospitalization.

Measured BMI will be divided by the mBMI for age and sex per national growth data to give the percentage mBMI.

The EDE-Q will be self-administered; scores range from 1 to 6, with higher scores indicating greater severity and a worse outcome.

Inclusion Criteria: Age 12-24 yrs Meets Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for AAN Hospitalized with medical instability, as defined by: night time heart rate (HR) <45 bpm, systolic blood pressure (SBP) <90 mmHg, temperature <35.6° C, orthostatic Δ HR >35 bpm, or orthostatic Δ SBP >20 mmHg Exclusion Criteria: Bulimia nervosa Current pregnancy Chronic disease (e.g. immune, renal disease) Acute/active suicidality or psychosis Hospital admissions for refeeding in the prior 6 mo.