Anorexia in Girls Is Linked to Autism, Study Finds
Autism Spectrum Disorder Basics
Prior to 2013, autism-related symptoms were grouped into five diagnosable conditions, called autistic disorder, Asperger’s disorder (also known as Asperger’s syndrome), childhood disintegrative disorder, Rett’s disorder (also known as Rett syndrome) and pervasive developmental disorder not otherwise specified. These conditions were defined separately because specialists at the American Psychiatric Association (APA) felt that scientific evidence and practical experience supported their existence as unique, distinct mental health concerns. However, in 2013, the APA concluded that evidence and experience now indicate the presence of a significant amount of overlap between the symptoms of the five autism-related conditions. In line with this conclusion, the organization eliminated the five conditions as separately diagnosable disorders and set the definition for autism spectrum disorder, which serves as a replacement diagnosis for all autistic symptoms.
People with anorexia nervosa develop ingrained eating habits that result in a loss of more than 15 percent of their normal body weight. Underlying these habits are an obsession with the maintenance of a thin appearance, an inability to accurately gauge physical appearance and an aversion to eating in general or to the consumption of specific types of food. Anorexic individuals may supplement their restrictive eating patterns with such things as extreme exercise routines, intentional vomiting after eating or the abuse of nonprescription diet aids, laxatives or diuretics. While some men and boys develop anorexia, roughly nine out of every 10 affected individuals are women or girls.
People with autism spectrum disorder commonly experience an unusual inability to display empathy, an attribute characterized by the capacity to emotionally or intellectually understand the motivations of others. They also commonly have a preference for maintaining predictable daily routines and repeating certain behaviors regularly over time. Doctors can measure a person’s level of empathy with a test called the Empathy Quotient or EQ test. They can also measure a person’s level of preference for predictability and set behavioral patterns with the help of a test called the Systemizing Quotient or SQ test. In addition, doctors can measure a person’s overall level of autistic personal and social traits with the help of a test called the Autism Spectrum Quotient or AQ test.
In the study published in Molecular Autism, a British research team gave the EQ, SQ and AQ tests to 66 girls between the ages of 12 and 18 who had been diagnosed with anorexia but did not have a diagnosis for autism spectrum disorder. After analyzing the results of these tests, the researchers found that, when compared to teenage girls unaffected by anorexia or autism, teenage girls with anorexia have a 400 percent greater chance of receiving AQ test scores that fall into the same range as the scores received by people diagnosed with autism spectrum disorder. They also found that, just like people diagnosed with autism spectrum disorder, teen girls diagnosed with autism receive unusually low scores on EQ tests and unusually high scores on SQ tests.
The authors of the study in Molecular Autism identify several specific personality traits that commonly appear in both individuals diagnosed with anorexia and individuals diagnosed with autism spectrum disorder. These traits include an unwillingness to change established behavioral patterns, a preoccupation with various kinds of detail, a tendency to hold inflexible points of view and a preoccupation with an inner, self-focused world. The research team believes that this overlap in traits may mean that anorexia and autism spectrum disorder represent different manifestations of an underlying preference for a highly structured, ordered mental environment. The team also believes that knowledge of this underlying preference may help doctors and researchers develop new treatments that pinpoint the motivating factors in both of the two disorders.