Brains of patients who have recovered from bulimia nervosa show persistent changes that may offer clues to understanding biological contributions, according to researchers at the University of Pittsburgh Medical Center. The findings, published in the June 28 issue of The American Journal of Psychiatry, are evidence that scientists are making progress in localizing regions of the brain that may make people susceptible to developing bulimia nervosa and other eating disorders.

Walter H. Kaye, M.D., professor of psychiatry in Pitt’s School of Medicine, and Guido Frank, M.D., visiting instructor in the Department of Psychiatry at Pitt, used positron emission tomography (PET) to take pictures of brain activity in women who had been in remission from bulimia nervosa for at least a year. The images showed that alterations of part of the brain’s serotonin system persisted after recovery. The findings are significant for a number of reasons, according to Kaye, Frank, and their colleagues, because the serotonin system directly affects the regulation of mood, appetite, and impulse control.

The researchers compared women who were in remission from bulimia for at least a year with healthy volunteers who had never had an eating disorder. The women’s brains were imaged by PET, and data from the individual images were averaged and compared against each other. The set of data from recovered bulimics showed that they did not experience a normal age-related decline in serotonin binding and that they had a reduction of serotonin binding in their orbital frontal cortex that was not evident in the images from the healthy women.

“The images support the possibility that these alterations may be related to the control of appetite, mood, and impulse control, and thus may make some women vulnerable for developing an eating disorder. Moreover, the fact that serotonin activity did not normally change with age offers important clues as to why bulimia nervosa may develop in teenage years,” said Kaye.

In addition to the changes uncovered by imaging, the women who had recovered from bulimia nervosa had significantly higher scores on the Eating Disorders Inventory, the Spielberger State-Trait Anxiety Inventory, and the Beck Depression Inventory, standard tests mental health professionals use to assess risk.

Current studies at UPMC are investigating genes that may contribute to this finding. For more information or to volunteer for studies, visit www.anbn.org.