A slimming program for eating disorders not otherwise specified - Reconceptualizing a confusing, residual diagnostic category

Eating disorders (EDs) are culture-bounded syndromes of abnormal eating beh avior, driven by psychopathology, primarily overvalued beliefs in the benef its of slimming, which lead to potentially serious physiologic abnormalitie s and regressive changes in social function. The essential features of the disorder are syndromic, a cluster of signs and symptoms with cross-sectiona l and longitudinal consistency, rather than a disorder understood by a sing le defined etiology. Despite its syndromic nature, the diagnostic criteria for the hive best understood EDs, anorexia nervosa (AN) and bulimia nervosa (BN), are validated and widely accepted. Many cases do not meet the strict criteria for AN or BN. These cases are included within the third, residual category of EDs in the fourth Diagnostic Manual of the American Psychiatri c Association (DSM-TV) as eating disorder not otherwise specified (EDNOS) o r atypical cases. The category of EDNOS is inherently troublesome for several reasons. Numero us eating disorder programs have reported that 25% to 60% of cases treated fall into the EDNOS category.(2, 6, 9) This number of atypical cases sugges ts that either the AN and BN diagnoses are too narrow, defined by research based criteria, or that additional categories are needed for cases now dire cted by exclusion into EDNOS. An EDNOS diagnosis often leads to uncertainty of therapeutic methods because clinicians who routinely treat AN and BN co mplain they feel confused about how to treat atypical eating disorder cases . Sadly, some managed care companies frankly state in advance of a diagnost ic evaluation that if the patient is given a diagnosis of EDNOS, no coverag e will be provided, the implication being these are not true eating disorde rs. EDNOS is problematic because it is too large a group, too heterogeneous , and its qualifications are more exclusionary than inclusionary. EDNOS cau ses confusion regarding treatment and is sometimes considered invalid as a diagnosis by third party payers. We hypothesize that most EDNOS cases belong within the current AN or BN cat egories. This hypothesis can be tested by demonstrating how subgroups of th e current EDNOS category meet the essential and critical diagnostic feature s of AN and BN. These features include similarity in age, length of illness , core psychopathology, response to treatment, and response to psychologic tests. The psychologic tests include both specific eating disorder instrume nts, such as the Eating Attitudes Test (EAT) and the Eating Disorder Invent ory (EDI), as well as tests of general psychologic symptomatology, such as the Minnesota Multiphasic Personality Inventory (MMPI), and the Beck Depres sion Inventory (BDI). A logical consequence of the critical examination of the current EDNOS admi xture of cases is to suggest a revised set of diagnostic criteria for AN an d BN. If EDNOS cases formerly excluded from AN or BN are subsumed into thes e categories, the diagnostic criteria for AN and BN must be revised to acco mmodate these immigrants. There will always be some cases that fall within the general category of an eating disorder because they lack some essential criterion. Williamson et al(9) used cluster analysis to examine 46 EDNOS p atients and found three distinct subgroups: subthreshold anorexia nervosa, bulimia nervosa non purging subtype, and binge-eating disorder.