HIGHER CALORIE REFEEDING IN ATYPICAL ANOREXIA NERVOSA: SHORT-TERM OUTCOMES FROM THE STUDY OF REFEEDING TO OPTIMIZE INPATIENT GAINS (STRONG)

StRONG was a multicenter randomized clinical trial of refeeding in hospitalized adolescents and young adults with malnutrition secondary to anorexia nervosa (AN) and atypical anorexia nervosa (AAN) (ClinicalTrials.gov #NCT02488109). At end-of-treatment, higher calorie refeeding (HCR) was more efficacious and less costly than lower calorie refeeding (LCR). Here we compare efficacy of HCR in AAN vs. AN. Participants were N=120, 12-24 yr-olds with > 60% median Body Mass Index (%mBMI) and medical instability. AAN was defined as %mBMI >85% at baseline. Meal-based HCR began 2000 calories/day (kcal/d) and advanced 200 kcal/d; LCR began 1400 kcal/d and advanced 200 kcal every other day (no tube feeding). Efficacy was defined as time to restore a 6-point Medical Stability Index (MSI): heart rate (HR) ≥ 45 bpm; systolic blood pressure (SBP) ≥ 90 mmHg, temperature ≥ 35.6° C, orthostatic increase in HR ≤ 35 bpm and decrease SBP ≤ 20 mmHg, and ≥ 75% median BMI (%mBMI). Main outcome was days to restore MSI, compared between groups with unpaired t-test. Exploratory moderator analyses examined the interaction between refeeding treatment and diagnosis on key outcomes (time to recover heart rate and weight gain). Weight gain was defined as change in %mBMI. Modified intention to treat analyses included N=111. Mean age was 16.5 (2.5) yrs, 43% had AAN. Upon admission, %mBMI was 95.2 (9) in AAN vs. 76.5 (5.9) in AN, p