Physiological Abnormalities Related to Bulimic Behaviors and Physical Symptoms: Toward a Biobehavioral Analysis.
Date of Award
Doctor of Philosophy (PhD)
Bulimia is an eating disorder characterized by secretive binge-eating and abnormal weight-control practices such as self-induced vomiting, and laxative abuse. To date, investigations of physiological abnormalities accompanying bulimia are recent, few in number, and descriptive in nature. Commonly reported physiological abnormalities have included: increased serum bicarbonate, usually in combination with decreased serum chloride; decreased serum potassium; and decreased hematocrit. Two correlations have provided preliminary evidence that bulimic behaviors are associated with physiological abnormalities. The present investigation attempted to describe more fully the relationships among bulimic behaviors, physiological abnormalities, and physical symptoms. Three separate models, representing different physiological systems: (1) potassium; (2) chloride-bicarbonate; and (3) hematocrit, were proposed and investigated. Forty bulimic women, hospitalized for the treatment of bulimia, were administered standard blood tests, psychological tests, and eating disorder inventories. Sample characteristics approximated those of other studies; and results indicated that 67.5% of the sample demonstrated some sort of physiological abnormality. Lethargy and depression were commonly reported symptoms. Although 37.5% demonstrated decreased hematocrit, no hypothesis concerning the relationships among bulimic behaviors, hematocrit, and physical symptoms was supported. Also, no hypothesis concerning the chloride-bicarbonate system was supported. Potassium level was significantly related to laxative abuse and body weight, suggesting that body weight may act as a mediating variable in the relationship between laxative abuse and hypokalemia. Hypokalemia was significantly related to one physical symptom: muscle weakness. Investigation of other physiological variables showed striking abnormalities of red blood count, and inorganic phosphorous. Correlations between eating disorder inventory scores and physiological abnormalities suggested high BULIT scores may be indicative of physiological abnormalities. In sum, results of the present investigation indicated that physiological abnormalities were widespread, and provided guidelines to assist in assessing the physical risk status of bulimic patients. Frequent laxative abuse, muscle cramps, decreased body weight, and high BULIT scores, alone or in combination, may function as signs of increased risk. Self-reports of bulimic symptoms were infrequently involved in significant correlations. This relative lack of association may be due to invalid measures, or distorted reporting of bulimic behaviors. More probably it is related to the infinite complexity of physiological systems, not adequately represented in the present investigation. Future research might more profitably focus on a single physiological system.
Hinz, Lisa Dee, "Physiological Abnormalities Related to Bulimic Behaviors and Physical Symptoms: Toward a Biobehavioral Analysis." (1987). LSU Historical Dissertations and Theses. 4398.