Laboratory screening for electrolyte abnormalities and anemia in bulimia nervosa: A controlled study

Objective: Abnormal eating patterns and recurrent purging behaviors can res ult in significant medical complications. The purpose of this study was to assess the frequency of abnormalities in clinical laboratory tests in patie nts with bulimia nervosa who reported being otherwise in good health. Metho ds: Subjects included nonhospitalized women (N = 74) who met criteria for b ulimia nervosa outlined in the 3rd Rev. ed. of the Diagnostic and Statistic al Manual of Mental Disorders. They also reported use of self-induced vomit ing and/or laxatives as compensatory behaviors (purging subtype). The contr ol group (N = 110) included female volunteers with no history of a psychiat ric disorder. All subjects reported being in good medical health, were medi cation free, and were in a normal weight range. Blood samples were analyzed in the hospital clinical laboratory. Results: Compared with controls, pati ents showed more frequent occurrence of low values for serum potassium (6.8 % vs. 0.9%; p < .05) and chloride (8.1 % vs. 0.9%; p < .02). Electrolyte ab normalities occurred most often in patients with frequent bulimic episodes. Study groups did not differ significantly in frequency of abnormal hemoglo bin concentrations. Discussion: These results help to clarify the expected frequency of electrolyte abnormalities in individuals with bulimia nervosa who report otherwise good medical health. The substantial frequency of hypo kalemia and hypochloremia underscores the importance of an appropriate medi cal assessment for individuals with this disorder. (C) 2001 by John Wiley & Sons, Inc.