Reprinted from Eating Disorders Review
January/February 2005 Volume 16, Number 1
©2005 Gürze Books
Childhood anxiety may be one important genetically mediated path toward the development of anorexia nervosa and bulimia nervosa, according to a recent study by Dr. Walter Kaye and colleagues with the Price Foundation Collaborative Group (Am J Psychiatry 2004;161 (12):2215). A previous study of twins identified a common genetic factor that influences a tendency to develop anxiety, depression, and eating disorders symptoms, and several other studies have shown that in most cases, anxiety disorders precede the onset of anorexia nervosa or bulimia nervosa.
Dr. Kaye and his team used the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID) and standardized measures of anxiety, perfectionism, and obsessionality to study 97 persons with anorexia nervosa, 282 with bulimia nervosa, and 293 with anorexia nervosa and bulimia. The vast majority of individuals in each subcategory were women, and 63.5% of the entire group had at least one lifetime anxiety disorder. The scores from the interviews and tests were then compared with those of a group of 694 healthy women from the community who had no history of an eating disorder and no first-degree relatives with an eating disorder.
Anxiety disorders were common
As the researchers had predicted, about two-thirds of the individuals with eating disorders had one or more lifetime anxiety disorders. The most common disorders were obsessive-compulsive disorder, or OCD (277 patients, or 41%), and social phobia (134 patients, or 20%). Most reported that their anxiety disorder emerged during childhood, before they developed an eating disorder. Furthermore, those with a history of an eating disorder who weren’t currently ill and never had a diagnosis of an anxiety disorder still tended to be anxious, perfectionistic, and harm-avoidant. The presence of an anxiety disorder or an eating disorder tended to make these symptoms worse.
The authors reported that persons with anorexia nervosa, bulimia nervosa, or anorexia and bulimia had relatively similar rates of all anxiety disorders. An exception was post-traumatic stress syndrome, which was approximately three times more common among patients with bulimia nervosa and those with anorexia/binge-eating and purging subtype and bulimia than those with anorexia nervosa/restricter subtype.
Early onset of anxiety noted
This study showed that the onset of OCD, social phobia, specific phobias and generalized anxiety disorder usually preceded the onset of an eating disorder. Forty-two percent of the people with eating disorders in the total sample reported having one or more anxiety disorders during childhood, a much higher rate than the usual frequency of overall anxiety disorders during childhood (4% to 7%). This was a notable finding because the onset of OCD among women is often in their 20s, according to the authors.
Finally, the authors found that scores on measures of anxiety, harm avoidance, obsessionality, and perfectionism tended to be the highest in persons who had a lifetime diagnosis of an anxiety disorder and who were currently ill with an eating disorder. However, individuals who never had anxiety disorder and who had been recovered from an eating disorder for at least 12 months before the study began reported higher levels of anxiety, harm avoidance, and perfectionism than did the healthy women. This suggested that anxiety symptoms are traits present in most people with eating disorders, even if they do not meet DSM-IV criteria for an anxiety disorder.