Brief Reports zyxwvutsrqponmlkjihgfedcbaZYXWVUTSR CSF Cholecystokinin Octapeptide in Patients With Bulimia Nervosa and in Normal Comparison Subjects R. Bruce Lydiard, Ph.D., M .D ., Timothy D . Brewerton, M .D ., M ark D . Fossey, M .D ., Michele T . Laraia, R.N ., M.S.N., Gail Stuart, R . N . , Ph . D . , Margery C. Beinfeld, Ph.D., and James C . Ballenger, M . D . Cholecystokinin octapeptide (CCK-8) appears to modulate appetitive behavior, and in ro- dents, anxiety-related behavior. The authors studied CCK-8 in patients luith bulimia nervosa. CSF concentrations of CCK-8 were measured in 11 drug-free female patients with DSM-III- R-defined bulimia nervosa and in 16 normal subjects. The bulimic patients had significantly lower levels of CCK-8 than the comparison subjects. CCK-8 concentrations were inversely correlated with scores on the anger-hostility, attxiety, and interpersonal sensitivity subscales of the SCL-90-R. They were not significantly correlated with age, percentage of standardized average body weight, or mean weekly frequency of binge eating or vomiting. The results indicate that central CCK-8 abnormalities may play a role in the pathophysiology of bulimia nervosa. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA (Am J Psychiatry 1993; 150:1099-1101) C holecystokinin is a neuroactive peptide that exists in various forms and exhibits a variety of both peripheral and central nervous system (CNS) actions (1, 2). Cholecystokinin octapeptide (CCK-8) exists in the gut in high concentrations and is believed to be the most prevalent form of cholecystokinin in the CNS (1, 2). Bulimic patients typically demonstrate impaired satiety responses to eating and also frequently exhibit high anxiety levels. Preclinical and clinical studies show CCK-8 to be an important mediator of satiety in ani- mals and humans (3-5). Geracioti and Liddle (6) re- ported that plasma CCK-8 responses to a liquid test meal were significantly lower in normal-weight patients with bulimia nervosa than in control subjects. Preclini- cal studies suggest that there may be a functional rela- tion between CNS cholecystokinin and benzodiazepine Received Feb. 18, 1992; revision received Oct. 23, 1992; accepted Nov. 10, 1992. From the Institute of Psychiatry, Medical University of South Carolina. Address reprint requests to Dr. Lydiard, Institute of Psychiatry, Medical University of South Carolina, 171 Ashley Ave., Charleston, SC 29425. Supported in part by N I H grants RR-001070 and NS-18667. Copyright © 1993 American Psychiatric Association. receptor function (7, 8). The tetrapeptide form of chole- cystokinin has been shown to be a potent anxiogenic agent in humans, particularly in panic disorder patients (9-11). To date there has been no investigation of po- tential abnormalities in CNS cholecystokinin function in patients with bulimia nervosa. We report here CSF concentrations of CCK-8 in drug-free female patients with DSM-III-R-defined bulimia nervosa and in normal comparison subjects. METHOD The patients and normal subjects were recruited through local re- ferrals and newspaper advertisements. All patients and normal sub- jects were interviewed with the Structured Clinical Interview for DSM-III (12), which was modified for DSM-lll-R diagnoses. Patients with bulimia nervosa were included if they had hinged and purged an average o f at least three or more times per week for at least 6 m o n t h s prior to the study. Potential comparison subjects were excluded if they had lifetime or family histories (in first-degree relatives) of any major psychiatric illness. In addition, all of the normal comparison subjects were free of significant medical illnesses on the basis of physi- cal examinations and routine laboratory tests. A l l s t u d y subjects were medication free for at least 4 weeks before the study began. Patients and normal subjects were admitted to the Medical Univer- Am J Psychiatry 150:7, July 1993 1099