Identifying Networks Integrating Anxiety and Metabolism in human Anorexia Nervosa by measuring effects of Caloric and Non-Caloric Meals in the explanatory Randomized NAMA Trial

Anorexia nervosa (AN) is an eating disorder that is mediated by psychological and metabolic factors, yet it is unclear how these factors interact. The NAMA trial objective is to clarify the metabo-psychiatric interaction and identify how it affects AN-patients' behavior. This randomized trial will recruit 36 treatment-naïve female AN patients, 13-18 years of age, and 36 matched healthy controls. Participants will undergo psychiatric assessments followed by 12-hour overnight fasting. In the next morning baseline assessments of outcomes will be performed. Patients will be randomly allocated 1:1 to receive a mixture with calories or receive a mixture without calories. Healthy controls will also be allocated to receive mixtures with/without calories. Mixtures will be standardized for taste and appearance and allocation will be masked. Primary outcome measure is resting-state functional magnetic resonance brain imaging 60 minutes post-consumption of the mixture. Secondary outcomes include: 1. Blood samples to study markers reflecting metabolic states, hunger/satiety, and stress responses, 2. psychometric evaluations of subjective experiences, and 3. In a second meal 3 hours later, effects of previous calorie intake on subsequent food consumption will be assessed. This article describes the study protocol, including analysis plan, for a randomized controlled trial to comprehensively evaluate the effects of calorie intake in AN. The trial will distinguish psychological and metabolic neuronal networks associated with food intake and uncover how their integration affects food intake and other hallmark symptoms in AN. The aim is to accelerate treatment development by identifying brain mechanisms that drive AN. Clinicaltrials.gov identifier: NCT06814002.