ABSTRACT
The term “comorbidity” was introduced in the medical literature by Feinstein (1) to refer to patients with two co-occurring diseases. In recent years, this concept has become well known in the field of psychiatry. Extensive comorbidity has been documented among a number of psychiatric disorders, not the least of which are eating disorders. Such comorbidity has several important clinical and research implications, as reviewed by Klein and Riso (2). First, the presence of comorbid disorders may affect the course and treatment response of the primary disorder. Second, comorbidity can make it unclear as to whether associations between the primary disorder and other variables are true associations or instead correlations with a comorbid condition. Third, a great degree of comorbidity may lead to reevaluation of the validity of a diagnostic category. That is, it may suggest an alternative diagnostic grouping. Fourth, high rates of comorbidity may provide important information regarding the etiology of the primary disorder, as well as the comorbid disorders.
