Anorexia Nervosa

Extreme anorexia nervosa: medical findings, outcomes, and inferences from a retrospective cohort

Journal of Eating Disorders
By Dennis Gibson, MD, FACP, CEDS Philip S. Mehler, MD, FACP, FAED, CEDS Jeana Cost, MS, LPC, CEDS

Research Asset


Background: Extreme anorexia nervosa (AN) is defined as a BMI < 15 kg/m2 in those meeting DSM-V diagnostic criteria for AN. This study seeks to define the frequency of medical complications in this group of patients in order to help inform the care of individuals < 65% ideal body weight who seek treatment for their extreme eating disorders.

Methods: Through retrospective chart review and computerized data collection, we obtained the baseline characteristics and medical findings of 281 adult patients, with AN restricting and binge-purge subtypes, admitted to the ACUTE unit for medical stabilization between May 2013 and August 2018.

Results: In this population, with a mean admitting BMI of 12.1 kg/m2 (range = 7.5–15.7), 56% admitted with bradycardia, 45% demonstrated increased liver function tests (LFTs) on admission, 64% admitted with leukopenia, 47% with anemia, and 20% presented with thrombocytopenia. During admission, 38% developed hypoglycemia, 35% developed refeeding hypophosphatemia, nearly 33% of patients developed edema, and low bone mineral density was diagnosed in almost 90% of the patients. Highly elevated LFTs (>3x upper limits of normal) predicted hypoglycemia, and low BMI predicted refeeding hypophosphatemia (p = .001).


Although conclusions drawn from the findings presented in this descriptive study must be tempered by relevant clinical judgement, these findings showcase that patients with extreme AN are at significantly increased risk for many serious medical complications secondary to their state of malnutrition and also with initial refeeding.

Written by

Dennis Gibson, MD, FACP, CEDS

Dennis Gibson, MD, FACP, CEDS serves as the Clinical Operations Director at ACUTE. Dr. Gibson joined ACUTE in 2017 and has since dedicated his clinical efforts to the life-saving medical care of…
Written by

Philip S. Mehler, MD, FACP, FAED, CEDS

Dr. Philip S. Mehler began his career at Denver Health more than 35 years ago and was formerly its Chief of Internal Medicine and then Denver Health’s Chief Medical Officer (CMO) until he was promoted…
Written by

Jeana Cost, MS, LPC, CEDS

Jeana Cost is the Vice President of Operations and Clinical Services of the ACUTE Center for Eating Disorders & Severe Malnutrition. In her role, she is tasked with ensuring an excellent patient…

ACUTE Earns Prestigious Center of Excellence Designation from Anthem
In 2018, the ACUTE Center for Eating Disorders & Severe Malnutrition at Denver Health was honored by Anthem Health as a Center of Excellence for Medical Treatment of Severe and Extreme Eating Disorders. ACUTE is the first medical unit ever to achieve this designation in the field of eating disorders. It comes after a rigorous review process.

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