Neurocognitive evidence favors "top down" over "bottom up" mechanisms in the pathogenesis of body size distortions in anorexia nervosa.

Perceptually-based disturbances in body image, or body size distortions, have been posited to occur in anorexia nervosa (AN). Perception does not result from a simple flow of sensory information from periphery to cortex ("bottom-up" processing), but involves the selection of inputs most likely to be relevant in light of an individual's experience and expectations ("top-down" processing). Most investigations of body size distortion in AN have used procedures likely to engage top-down processing, raising the possibility that attitudinal disturbances may play a role. To our knowledge, there have been no studies that assess the presence, in AN, of neurocognitive deficits associated with neurologically based disturbances in body schema. Such deficits, if found, could provide evidence of body image distortion unlikely to result from top-down processing. We tested 20 inpatients with AN on measures of proprioception, finger identification, right/left orientation, general cognition and eating disorders symptomatology, both before and after treatment. Matched normal controls were tested on the same measures over the same time intervals. Significant differences between the two groups occurred only prior to treatment, and only on those measures which involved executive, in addition to more body-schema-specific functions. This suggests that patients with AN do not have enduring deficits in the domain of body-schema, but may have subtle cognitive dysfunction, in the acute state, which is not specific to, but can interact with processing of body-schema-related information. This, in turn, suggests that their body image distortion may not be secondary to bottom-up perceptual disturbances.

Changing patterns of hospitalization in eating disorder patients.

OBJECTIVE: This study investigated the changing patterns of hospitalization of eating disorder patients over the past 15 years. METHOD: The records of 1,185 eating disorder patients between 1984 and 1998 were examined on several variables. RESULTS: Over the 15 years, the number of first admissions increased from 20 to 182. There was a concomitant decrease in length of stay from 149.5 days in 1984 to 23.7 days in 1998. Readmissions increased markedly from 0% during the first year to 27% of total admissions in 1998. The discharge weight of anorectic patients significantly decreased from a body mass index (BMI) of 19.3 in 1984 to 17.7 in 1998. These changes were particularly salient in the past 3 years, concurrent with a dramatic rise in managed care cases. CONCLUSIONS: Over the past 15 years, eating disorder hospital treatment has metamorphozed from long-term treatment of a disorder to stabilization of acute episodes. For some patients, this change has been deleterious and not cost effective.

Substance dependence and eating disorders: impact of sequence on comorbidity.

There is a high comorbidity between eating disorders and substance dependence. The sequence of illness may indicate differences in the underlying pathology and could reflect different etiologies and treatment. The present study subjects were 218 inpatients and outpatients with diagnoses of anorexia nervosa binge-purge type (AN-BP), bulimia nervosa (BN), and eating disorder NOS (ED-NOS). Of these 218 patients, 38 had substance dependence predating the eating disorder (SDED), 71 had an eating disorder predating the substance dependence (EDSD), and 109 had only an eating disorder (ED-only). All subjects were administered the Structured Clinical Interview for DSM-III-R, Patient Edition With Psychotic Screen (SCID-P). EDSD patients had an earlier onset of the eating disorder than SDED patients and had the greatest prevalence of comorbid pathology. SDED patients were dependent on more substances. We conclude that the sequence of development of the eating disorder and substance dependence in eating disorder patients influences the amount of comorbid psychopathology. Clinical implications and future research are discussed.

Smoking and body image concerns in adolescent girls.

OBJECTIVE: Use of cigarettes has increased dramatically among adolescent females. Because young women use smoking as a weight control strategy, increased drive for thinness and body dissatisfaction may be associated with smoking. This study examined the relationship between smoking and body image concerns among adolescent females with and without eating disorders. METHODS: Incidence of smoking and Eating Disorders Inventory (EDI) scores were compared among 411 nonclinical females and 82 eating disorder females with anorexia nervosa or bulimia nervosa aged 11 to 18. RESULTS: Of the three groups, anorectic-restrictors were the least likely and bulimics the most likely to smoke. After covarying age, both eating disorder and nonclinical smokers had significantly greater psychopathology on Drive for Thinness, Body Dissatisfaction, and Interoceptive Awareness than nonsmokers. DISCUSSION: Despite high levels of body image disturbance, anorectic-restrictors did not use smoking as a weight control strategy. Body image concerns were more prevalent in smokers than in nonsmokers.

Eating disorders.

The eating disorders remain perplexing treatment challenges. These disorders are best understood through the clustering of their symptoms and with a multidimensional model. Treatment must follow from the observed symptoms and cannot always follow a standardized course as is done in other psychiatric disorders. CBT is the most efficacious treatment for both AN and BN.