Nothing “Atypical” About Atypical Anorexia

 
 

When people hear the word ‘anorexia,’ a stereotypical image of an extremely thin person often comes to mind. This stereotype is based on the stigma that eating disorders involving restriction only happen to people in small bodies. Anorexia nervosa (AN) is a serious mental health issue with the second highest mortality rate of all mental health diagnoses, second only to opioid use[2]. The lifetime prevalence rate of AN is about 0.6%[3].

However, we cannot talk about anorexia without also talking about a newer recognized disorder, Atypical Anorexia Nervosa (AAN). Both the name ‘atypical’ and how it is categorized in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR) imply that this disorder is somehow less serious or less common. AAN is a subcategory under Other Specified Feeding and Eating Disorders (OSFED)[1]. The criteria states: “individuals who meet all criteria for anorexia nervosa except that despite significant weight loss, weight is in the normal or above normal range.” Other criteria for AN include fear of gaining weight or behavior that interferes with weight gain; as well as body shape and weight disturbance.

AAN demonstrates lifetime prevalence rates up to 2-3 times higher than that of AN[5]. However, because individuals with AAN are often at a “normal” or higher BMI, their diagnosis is often missed due to inaccurate beliefs that someone at that weight cannot have a restrictive eating disorder. This is harmful because it often delays the onset of treatment or leads providers to perceive that AAN is not as serious as AN. Many clients have come to therapy hearing their weight loss celebrated by family, friends, and at times medical providers, despite struggling with a serious eating disorder.

AAN is as, if not more, prevalent than AN, which itself implies it is not atypical, but let’s also consider the medical complications. Research has consistently demonstrated that individuals with AAN demonstrate similar, and at times more severe, medical and psychological complications compared to AN. Individuals with AAN are at risk for all of the following[7]:

  • Electrolyte imbalance, including hypophosphatemia (low phosphorus), hypokalemia (low potassium), hyponatremia (low sodium) and/or hypomagnesemia (low magnesium)

  • Impaired renal function

  • Hypotension (low blood pressure), bradycardia (low heart rate), orthostasis (positional changes resulting in abnormal heart rate or blood pressure), and electrocardiographic (EKG) abnormalities

  • Seizures

  • Alterations in brain function

  • Delayed gastric emptying

  • Nausea, bloating, constipation, vomiting

  • Amenorrhea in women and suppression of testosterone in men

  • Reduced bone mineral density

    *Bone density tends to be better in AAN, compared to AN; however, it is worse than compared to a non-eating disorder population[6]

Of note, individuals with AAN are also at risk for refeeding syndrome when undergoing recovery. This is a potentially fatal rapid shift in electrolytes due to an increase in carbohydrate intake after a period of malnourishment, which can lead to a multi-organ system failure. It is important that someone with AAN be closely monitored by a medical professional. Body size and BMI are not reliable indicators that someone is not ‘sick enough’ to warrant treatment (a statement often heard in this field). Research demonstrates that increased rate, amount, and duration of weight loss, across a range of body weights, is associated with increased medical severity and that these factors should be taken into account when treating AAN[4].

Internalized weight stigma among both mental health and medical providers is very real and creates barriers in access to care. The weight restoration and renourishment process can involve moving someone back to the weight in which their body can both physically and psychologically thrive, despite any preconceived beliefs about size and health. Both AAN and AN are severe, potentially life threatening illnesses that deserve prompt, compassionate, evidence-based treatment.

Looking for further consultation regarding eating disorders? Get started with Dr. Hosford.

Start Your Journey

References

American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders: DSM-5-TR. American Psychiatric Association Publishing. https://doi.org/10.1176/appi.books.9780890425787

Bunnell, D. (n.d.). Statistics. NEDA. https://www.nationaleatingdisorders.org/statistics/

Eating Disorders (n.d.). NIH. https://www.nimh.nih.gov/health/statistics/eating-disorders

Garber, A. K., Cheng, J., Accurso, E. C., Adams, S. H., Buckelew, S. M., Kapphahn, C. J., Kreiter, A., Le Grange, D., Machen, V. I., Moscicki, A. B., Saffran, K., Sy, A. F., Wilson, L., & Golden, N. H. (2019). Weight loss and illness severity in adolescents with atypical anorexia nervosa. Pediatrics, 144(6), e20192339. https://doi.org/10.1542/peds.2019-2339

Harrop, E. N., Mensinger, J. L., Moore, M., & Lindhorst, T. (2021). Restrictive eating disorders in higher weight persons: A systematic review of atypical anorexia nervosa prevalence and consecutive admission literature. The International journal of eating disorders, 54(8), 1328–1357. https://doi.org/10.1002/eat.23519

Nagata, J. M., Carlson, J. L., Golden, N. H., Long, J., Murray, S. B., & Peebles, R. (2019). Comparisons of bone density and body composition among adolescents with anorexia nervosa and atypical anorexia nervosa. The International journal of eating disorders, 52(5), 591–596. https://doi.org/10.1002/eat.23048

Vo, M., & Golden, N. (2022). Medical complications and management of atypical anorexia nervosa. Journal of eating disorders, 10(1), 196. https://doi.org/10.1186/s40337-022-00720-9

Stephanie Sommers, PsyD