Atypical anorexia nervosa

Many of the physical symptoms of atypical anorexia nervosa are due to the effects of decreased caloric intake which causes the body to significantly suppress the metabolic rate. • Rapid, continuous weight loss • Bradycardia • Orthostatic instability These symptoms often are attributed to low body weight which is not seen in atypical anorexia nervosa. Other symptoms, such as bradycardia, appear at similar rates in AAN and AN. Patients with AAN are, like patients with AN, at risk of long-term effects of the disorder's physical symptoms such as osteoporosis. • Anxiety • Depression • Somatization • Social phobia It is common for patients with atypical anorexia nervosa to have co-morbid psychiatric disorders such as depression, anxiety, and OCD. Depressive and anxious disorders account for the majority of the comorbid disorders seen in association with atypical anorexia nervosa. However, there are limited studies on the prevalence of psychiatric illness in atypical anorexia nervosa. Researchers posit that patients with AAN may experience increased levels of body dysmorphia and dissatisfaction due to higher body weight. == Diagnosis ==

The diagnosis of atypical anorexia nervosa is carried out by a licensed health practitioner based on a clinical assessment which includes physical, psychiatric, and behavioral symptoms. DSM-5 criteria The diagnostic criteria used to diagnose psychiatric conditions are found in the Diagnostic and Statistical Manual of Mental Disorders (DSM) published by the American Psychiatric Association. The DSM-5 is the most current revision of the manual which was updated in 2013 to include atypical anorexia nervosa. This update addressed problems raised by the psychiatric community that the eating disorder section of the DSM-4 did not properly address the segment of patients who met many of the criteria of typical anorexia nervosa but did not meet the weight requirement of typical anorexia nervosa. Some suggest a transition to a "weight spectrum" rather than a universal weight cutoff, while other suggestions focus more on the non-weight-related symptoms of AN to reach a diagnosis of AAN. Following DSM-5 conditions of "significant weight loss" correlates with lower reported rates of AAN, though patients with higher weights may still experience symptoms of AN at high degrees. Even within studies which used higher weight cutoffs to define AAN, patients' other symptoms occurred at similar levels of severity. Alternative diagnostic manuals to the DSM-5 include the ICD-11. However, the ICD-11 also codes AN reliant on an underweight BMI and does not separately code AAN, thus excluding patients who exhibit the same cognitive and behavioral symptoms without the same degree of weight loss. The manual's own unique diagnoses have raised researchers' questions about shifting diagnoses related to the patient's stage of treatment as their weight and other symptoms may improve. == Treatment ==

The methodologies used by eating disorder treatment centers to treat anorexia nervosa generally also help those affected by atypical anorexia. Re-feeding and addressing any possible electrolyte imbalances is usually the first step in treating atypical anorexia nervosa, as complications from underlying electrolyte imbalances and malnutrition can be fatal. == Prognosis ==

Anorexia nervosa is one of the most difficult psychiatric disorders to treat and has a high mortality rate due to complications from malnutrition and suicide. Overall, the remission rates of atypical anorexia nervosa and anorexia nervosa are similar at 71% for atypical anorexia nervosa and 75% for anorexia nervosa. == Epidemiology ==

Prior to DSM-5, EDNOS made up the majority of eating disorder diagnoses, but it is difficult to determine what proportion of these diagnoses would now be categorized as atypical anorexia. The common assumption that eating disorder patients are thin and White leads providers to overlook assessment for eating disorders and disordered behaviors in non-White and overweight (or obese) teenagers. Weight judgment is prevalent globally among adolescents and adults alike; thus, overweight and obese patients may partake in restrictive eating without notice because of their higher BMI. For example, one prospective study of 196 women found a prevalence of 2.8% for atypical anorexia, compared to only 0.8% for anorexia nervosa by the age of 20. However, individuals experiencing atypical anorexia nervosa are less likely to receive care. In addition, when these individuals receive care, there is a higher rate of treatment dropout and decreased treatment response. Though data are mixed, some statistical analysis found increased hospitalization with a stronger trend in pediatric admissions than that of adults, and additional higher rates of readmission. Disorder symptoms–such as fear of weight gain–and co-morbid mental health disorders appear to have worsened. Researchers propose that LGBTQ+ teens are at higher risk because of increased social pressures about their appearance related to assumptions of gender. Research on these disparities is limited yet to conclude prevalence. == References ==