A STUDY OF ANOREXIA NERVOSA BASED ON THE ANALYSIS OF SLEEP EEG DATA

Abstract

Certain behavioral, affective, biological and sleep analogies have been noted in the literature between anorexia nervosa and primary depression. The present study sought to investigate further one of these potential links between these two disorders, i.e., the sleep characteristics of anorectic patients. It was hypothesized that the sleep polygraphic features of anorectic patients would differ from those of normal subjects and be in the direction of the described sleep characteristics of patients with primary depression. Specifically, significant differences were anticipated between anorectic and control groups in that (1) the REM latency values for the anorectic group would be significantly lower than the REM latency values for the control group; and (2) REM density would be significantly higher in the anorectic group than in the control group.;A total of thirty women were studied. Group "A" consisted of 20 subjects who met the defining criteria for anorexia nervosa. Group "B" consisted of 10 control subjects who were of similar age, menstruated regularly, were otherwise in good health, and did not have an eating disorder. Subjects were recruited from ongoing inpatient psychoendocrine studies conducted by the Department of Psychiatry and the Clinical Research Center of Montefiore Hospital and Medical Center. The Grass madel 78D EEG and polygraph recorder was used to measure the sleep activity of the subjects.;Comparing the two groups, significant differences were found in REM latency time, which was significantly reduced for the anorectic group. No significant differences were found between the two groups for REM density values. Additionally, no significant differences were found among the two groups for any of the remaining descriptive measures. Correlational data, within the anorectic group, indicated a significant negative correlation coefficient between REM latency values and Hamilton Scale depression scores. These data were compared to published norms and four models of interpretation were discussed. While some sleep indices were consistent with the hypothesis, the results were not powerful, in and of themselves, to demonstrate an undeniable link between anorexia nervosa and depression. However, it was felt that, when taken together with other supporting evidence in the literature, they do strengthen the suggestion that these two disorders are associated.