Objective: In the treatment of individuals with atypical anorexia nervosa (atypical AN), it is unclear how to determine when sufficient renourishment has been achieved. Reliance on body mass index (BMI) to define acute treatment goals in AN has led to gaps in understanding of the physiology of renourishment. Biological markers that reflect restoration of physical health during acute nutritional rehabilitation are needed to move beyond weight-based metrics.
Method: This Spotlight briefly describes the physiology of starvation in patients with AN and atypical AN and existing strategies for acute nutritional rehabilitation. It identifies gaps in understanding the timeline of physiological normalization during refeeding and proposes research to identify biological markers of restored physical health in individuals with AN and atypical AN.
Results: Physiological normalization during refeeding is not uniform across biological systems, with cardiovascular parameters correcting more rapidly than gonadal and skeletal systems. In AN, weight restoration improves most physiological indices, but the time course of biological recovery remains unclear. In atypical AN, data characterizing how biological indices of starvation change with refeeding are sparse.
Discussion: These observations underscore the utility of moving beyond approaches based exclusively on BMI. We propose the identification of biomarkers of physiological recovery as a necessary foundation for improved guidance regarding the renourishment of patients with AN and atypical AN.
Keywords: anorexia nervosa; atypical anorexia nervosa; biomarkers; estrogen; leptin.
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