How is the diagnosis of anorexia determined?
In many areas of medicine and healthcare, a diagnosis is made with the use of a diagnostic test, such as an x-ray or an MRI.
In the case of psychiatric illnesses, however, a diagnosis is often made on the basis of a patient’s subjective report about his or her symptoms, sometimes along with a family’s observation of the problem.
There are medical tests that can measure the extent of physical complications of anorexia, but there is not a physical “anorexia test,” per se. Instead, a diagnosis of anorexia nervosa, or any eating disorder for that matter, is made when a person’s symptoms meet the diagnostic criteria given in the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (Text Revision), or DSM-IV-TR for short.
Published by the American Psychiatric Association, the DSM-IV-TR provides a description of signs, symptoms, research findings, and guidelines that enable healthcare professionals to classify mental illnesses. Appropriately trained mental health professionals use the DSM-IV-TR in order to determine the best descriptive category for a person’s condition or problem.
Before receiving a diagnosis of anorexia, a person receives a thorough professional assessment and a medical exam in order to rule out any physical conditions or illnesses that may be causing symptoms similar to those seen in anorexia nervosa.
The following are the diagnostic criteria for anorexia nervosa as they appear in the DSM-IV-TR, followed by a few clarifying phrases:
A. Refusal to maintain body weight at or above a minimally normal weight range for age and height (e.g., weight loss leading to maintenance of body weight less than 85% of that expected; or failure to make expected weight gain during period of growth, leading to bodyweight less than 85% of that expected). This means that, according to the DSM-IV-TR, a person diagnosed with anorexia weighs roughly 85% or less of their ideal body weight as determined by standardized weight charts (or calculations of body mass) based on gender, height, and age.
Most anorexia patients are of a normal weight when their symptoms first appear, however, pre-pubertal patients may acquire symptoms while they are still physically developing and therefore fail to reach a normal weight.
B. Intense fear of gaining weight or becoming fat, even though underweight. The type of fear referred to here is more intense than a typical person’s concern about gaining a few pounds over the course of time.
C. Disturbance in the way in which one’s body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or denial of the seriousness of current low body weight. Anorexia patients over-value their weight and appearance. Although anorexia patients may be able to accurately state if another person appears too thin, they tend to be inaccurate about the assessment of their own body shape and size. Even if emaciated, many people with anorexia deny that their condition merits serious concern.
D. In postmenarcheal females, amenorrhea, i.e., the absence of at least three consecutive menstrual cycles. (A woman is considered to have amenorrhea if her periods occur only following hormone, e.g., estrogen, administration.)
Note: Many experts feel that this final criterion, amenorrhea, is too restrictive because some women who are at a very low weight continue to have their period, while some women lose their periods shortly after they begin dieting, even without extreme weight loss. Consensus suggests that patients with most of the key criteria of anorexia deserve to be diagnosed with this disorder and treated accordingly (Herzog and Eddy 2007). (See Question 7 for the male counterpart to the amenorrhea criterion.)
In addition, the DSM-IV-TR specifies two types of anorexia nervosa. When the diagnosis of anorexia nervosa is given, a healthcare professional will also specify which type of anorexia best describes the associated pattern of behavior: Restricting Type or the Binge-Eating/Purging Type.
Restricting Type: during the current episode of anorexia nervosa, the person has not regularly engaged in binge-eating or purging behavior (i.e., self-induced vomiting, misuse of laxatives, diuretics, or enemas)
Binge-Eating/Purging Type: during the current episode of anorexia nervosa, the person has regularly engaged in bingeeating (eating of a significantly large amount of food during a given period of time) or purging (self-induced vomiting, misuse of laxatives, diuretics, or enemas)
SOURCE: American Psychiatric Association. Diagnostic and statistical manual of mental disorders, 4th ed., Text Revision (p. 589).
There is a second resource that may be used in diagnosing anorexia: the International Classification of Diseases, 10th Revision (ICD-10). Like the DSM-IV-TR, the ICD-10 is a coding of signs, symptoms, and clinical findings that a healthcare professional might use to classify diseases and other health problems.
Broader than the DSM-IV-TR, it is used internationally to classify all diseases and other health problems, including mental illness. A physician or other healthcare professional might utilize the ICD-10 either in addition to or in lieu of the DSM-IV-TR. The descriptions of anorexia are similar in both references.
Eating disorder - A severe disturbance in eating behaviors that results in an altered consumption of food and may significantly impair physical or mental health. An eating disorder is not diagnosed when the disturbed eating behaviors are the direct result of a general medical condition.
Symptom - A sign or indication of a disorder, disease, or condition.
DSM-IV-TR - A manual that qualified mental health professionals use to diagnose mental illnesses.
Pre-pubertal - Before the onset of puberty.
Post-menarcheal - Having established menstruation.
Amenorrhea - The absence of menstrual periods in females.