INSULIN-RESPONSE IN BULIMIA-NERVOSA AS A MARKER OF NUTRITIONAL DEPLETION

Objective: The aim of this provocation study was to examine insulin, g lucose, and cortisol levels in response to a glucose load in bulimia n ervosa patients and to relate this to behavior, treatment status, and depressive symptomatology. Method: A 3-hr glucose tolerance test was p erformed in 15 female patients and in 4 controls. Tests were performed at different stages of treatment and following documented engagement in the patient's usual or previous repertoire of bulimic behaviors in the 24 hr prior to testing. Insulin, glucose, and cortisol levels were assayed at baseline and at 30-min intervals following the glucose loa d. Presence or absence of significant depressive symptomatology was as certained. Results: Three patterns of insulin response were identified : (1) an exaggerated response, (2) a normative response which resemble d that of healthy controls, and (3) a blunted pattern. A reciprocal re lationship between peak insulin and mean cortisol levels was seen with higher depression scores associated with blunted insulin response. Pa tients whose response was exaggerated binged and vomited relatively in frequently and were of stable weight. The insulin response of successf ully treated patients, abstinent from binging and vomiting for 4 weeks , was similar to that of normal controls. A blunted response occurred in patients who bing ed and vomited more frequently, whose weight was unstable, and whose baseline eating was chaotic or nonexistent. Discus sion: The exaggerated insulin response was seen as a physiological ada ptation to intermittent starvation reversible with treatment, while th e blunted insulin response associated with higher cortisol levels was seen to result from more constant nutritional deprivation secondary to greater disturbance of behavior. (C) 1996 by John Wiley & Sons, Inc.