Atypical Anorexia Nervosa: An Underrated Disease

What is Atypical Anorexia Nervosa?

Anorexia nervosa is a behavioral disorder that isn’t as black-and-white as described in the books. When someone mentions ‘anorexia,’ all we can think of is a lean, thin teenage girl, almost reduced to bones, unable to eat, drink, or menstruate like a normal girl. This condition is typical of anorexia nervosa. However, the disease is diverse when it comes to its exhibition.
To understand atypical anorexia nervosa, you must first learn what its typical version is.

Anorexia Nervosa Vs. Atypical Anorexia

Anorexia nervosa (AN) is medically defined as a neurotic loss of appetite. The patient is usually a young girl, probably in her teens, experiencing severe loss of appetite, loss of weight (about 25% from baseline), and amenorrhea. It has the highest mortality rate to date among other psychiatric illnesses¹Lindsay Moskowitz, Eric Weiselberg, Anorexia Nervosa/Atypical Anorexia Nervosa, Current Problems in Pediatric and Adolescent Health Care, Volume 47, Issue 4, 2017, Pages 70-84, ISSN 1538-5442, https://doi.org/10.1016/j.cppeds.2017.02.003.
What differentiates AN from atypical AN is the weight factor. Atypical anorexia nervosa may make you extremely anorexic and maybe amenorrheic, too. However, you may still appear physiologically normal.

Atypical Anorexia Nervosa Prevalence

Although less prevalent than AN, atypical anorexia nervosa (AAN) is significantly present in various communities. A study conducted on United States military veterans revealed AAN to be a highly prevalent and clinically significant diagnosis²Masheb, R. M., Ramsey, C. M., Marsh, A. G., Snow, J. L., Brandt, C. A., & Haskell, S. G. (2021). Atypical Anorexia Nervosa, not so atypical after all: Prevalence, correlates, and clinical severity among United States military Veterans. Eating behaviors, 41, 101496. https://doi.org/10.1016/j.eatbeh.2021.101496.
As eating disorder spectrums are revised annually and their definitions improvised accordingly, it has been discovered recently that about 25 to 40 percent of patients admitted due to eating disorders in specialized units for psychiatric care have atypical anorexia nervosa.³Neville H. Golden, Philip S. Mehler Cleveland Clinic Journal of Medicine Mar 2020, 87 (3) 172-174; DOI: 10.3949/ccjm.87a.19146
As per another source⁴ Atypical anorexia nervosa symptoms, risks, & treatment. ACUTE. (n.d.). https://www.acute.org/conditions/atypical-anorexia-nervosa , the prevalence of AAN by age 20 years is 28% (vs < 1% for anorexia nervosa)

Atypical Anorexia Nervosa Criteria

Diagnostic and Statistical Manual of Mental Disorders (DSM) has recently launched its 5th edition, which includes revised criteria for more than seventy psychiatric illnesses.
According to this manual, Anorexia Nervosa (AN) is diagnosed when:

• You eat significantly less in contrast to what your body requires, leading to substantially low body weight in context to your age, height, physical health, and developmental chart
• Despite being underweight, you fear becoming overweight or fat
• You have an unrealistic body image expectation and visualize yourself as normal despite being emaciated

DSM-5 diagnoses you with atypical anorexia nervosa when you meet one or all of the above-given criteria, except that you have a normal or above normal weight and your physical appearance is not impaired.

Atypical Anorexia Nervosa Causes

The causes of atypical AN are the same as those of AN. Eating disorders are usually a result of synergistic effects of psychological, biological, and environmental factors.

Biological:

Some people have a genetic predisposition to certain psychiatric tendencies, such as overthinking, perfectionism, anxiety, anger issues, etc. which can trigger eating disorders.

Psychological:

People with obsessive-compulsive personality traits are generally more likely to possess anorexic tendencies since it is easier for them to stick to a restrictive diet pattern

Environmental:

Cultures that favor lean and thin physiques generally trigger insecurity and anxiety in young adults who seem to fall on a higher side of the weight range. Body shaming and comparison are significantly responsible for anorexic behavior in teens.⁵Ma, R., Kelly, A.C. The fragility of perceived social rank following exercise in anorexia nervosa: an ecological momentary assessment study of shame and pride. Eat Weight Disord 25, 1601–1607 (2020). https://doi.org/10.1007/s40519-019-00797-3
Major life transitions or stress factors such as exams, change of city or job, loss of a loved one, etc., can also trigger AAN in young and middle-aged people.

Atypical Anorexia Nervosa Symptoms

Symptoms of AAN can be broken down into two components; emotional and physical.

Emotional symptoms:

• Anorexia nervosa makes you fearful of the consumption of calories. You will find yourself extremely restrictive towards the quantity and contents of your daily meal
• The fear of gaining weight will compel you to exercise uncontrollably
• Extreme cases can make you use laxatives and enemas after meals to get rid of the food. You may also find yourself inducing vomiting forcefully after eating in an attempt to get rid of extra calories.

Physical symptoms:

Given the restrictive eating pattern, anyone would expect an anorexic patient to look underweight and malnourished. As much as this is true for AN, it is totally the opposite for atypical anorexia nervosa. With AAN, you will experience all sorts of obsessiveness regarding restrictive caloric intake and weight gain; however, your physical appearance may appear normal. In fact, you may even be obese yet anorexic.
As emaciation is not a feature of AAN, these patients are less likely to receive the required psychiatric care as their signs are often misidentified.
However, your body still calls for help in various ways:

• Significant weight loss despite falling within the normal range
• Dry and pale skin
• Reduced immunity
• Altered bowel habits- you have constipation most of the time
• Easy fatigability/lethargy
• Non-specific abdominal pain

How serious is Atypical Anorexia Nervosa?

People often assume that AAN is harmless as it does not impact your weight. However, this is far from being true, as atypical anorexia nervosa damages your health as much as AN does. In fact, you may be more likely to suffer from complications of AAN as the disease is often misdiagnosed due to the lack of awareness.
Long-term effects include:

• Amenorrhea
• Brittle or weak bones that can break easily
• Cardiovascular depression
• Damage to vital organs
• Muscle wasting
• Suicidal thoughts
• Death due to prolonged starvation

Atypical Anorexia Nervosa Treatment

The major chunk of treatment of any eating disorder comprises psychotherapy. Prolonged and repetitive counseling is the mainstay treatment of AAN.

Cognitive Behavioral Therapy:

A 2019 Srilankan case study⁶Liyanage, N., Suraweera, C., & Rodrigo, A. (2019). Cognitive Behavioral Therapy Management of a Patient with Atypical Anorexia Nervosa. Case reports in psychiatry, 2019, 4736419. https://doi.org/10.1155/2019/4736419 has proven the beneficial effects of cognitive behavioral therapy on a young female who was suffering from AAN and moderate depressive disorder. The therapy helped her build a normalized eating pattern and overcome her sense of perfectionism.

Dialectical Behavioral Therapy (DBT):

DBT helps you learn and develop new coping skills. This therapy is particularly useful in treating eating disorders, as binge eating or starvation is a common coping method adopted by most of us to overcome grief or stress.⁷Peterson CM, Van Diest AMK, Mara CA, Matthews A. Dialectical behavioral therapy skills group as an adjunct to family-based therapy in adolescents with restrictive eating disorders. Eat Disord. 2020 Jan-Feb;28(1):67-79. doi: 10.1080/10640266.2019.1568101. Epub 2019 Jan 23. PMID: 30669955. DBT comprises four core skills, namely, mindfulness, distress tolerance, emotional regulation, and interpersonal effectiveness.

Family-based Treatment:

Most doctors believe that you heal well when your parents are an active part of your treatment. Hence, family-based therapy plays a crucial role in the treatment of atypical anorexia nervosa, as it focuses on the “core parental ability to feed their child.”

Conclusion:

Atypical anorexia nervosa is a common eating disorder that has been prevalent in teens and young adults for years. However, it has been recently recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM) as a separate entity. It differs from Anorexia Nervosa in a way that it does not impact your weight. Hence, you may normally weigh yet be extremely anorexic.
The treatment is quite similar to that of AN and mostly comprises psychotherapy.
Patients of AAN are generally misdiagnosed due to the fact that despite starving for months, they do not look malnourished or emaciated. This delays the treatment leading to serious health implications and irreversible damages such as vital organ failure and death.

Refrences

• 1
  Lindsay Moskowitz, Eric Weiselberg, Anorexia Nervosa/Atypical Anorexia Nervosa, Current Problems in Pediatric and Adolescent Health Care, Volume 47, Issue 4, 2017, Pages 70-84, ISSN 1538-5442, https://doi.org/10.1016/j.cppeds.2017.02.003.
• 2
  Masheb, R. M., Ramsey, C. M., Marsh, A. G., Snow, J. L., Brandt, C. A., & Haskell, S. G. (2021). Atypical Anorexia Nervosa, not so atypical after all: Prevalence, correlates, and clinical severity among United States military Veterans. Eating behaviors, 41, 101496. https://doi.org/10.1016/j.eatbeh.2021.101496
• 3
  Neville H. Golden, Philip S. Mehler Cleveland Clinic Journal of Medicine Mar 2020, 87 (3) 172-174; DOI: 10.3949/ccjm.87a.19146
• 4
  Atypical anorexia nervosa symptoms, risks, & treatment. ACUTE. (n.d.). https://www.acute.org/conditions/atypical-anorexia-nervosa
• 5
  Ma, R., Kelly, A.C. The fragility of perceived social rank following exercise in anorexia nervosa: an ecological momentary assessment study of shame and pride. Eat Weight Disord 25, 1601–1607 (2020). https://doi.org/10.1007/s40519-019-00797-3
• 6
  Liyanage, N., Suraweera, C., & Rodrigo, A. (2019). Cognitive Behavioral Therapy Management of a Patient with Atypical Anorexia Nervosa. Case reports in psychiatry, 2019, 4736419. https://doi.org/10.1155/2019/4736419
• 7
  Peterson CM, Van Diest AMK, Mara CA, Matthews A. Dialectical behavioral therapy skills group as an adjunct to family-based therapy in adolescents with restrictive eating disorders. Eat Disord. 2020 Jan-Feb;28(1):67-79. doi: 10.1080/10640266.2019.1568101. Epub 2019 Jan 23. PMID: 30669955.