Neuropsychological Functioning and Ghrelin Secretion in Women with Binge Eating

Abstract

Aims: Binge eating disorders have a substantial impact on the lives of those affected, both psychologically and physically. The trend towards using a transdiagnostic model to understand binge eating disorders highlights the importance of understanding specific characteristics associated with binge eating rather than relying on diagnostic groupings to inform treatment. The aims of the current study were to examine neuropsychological functioning and ghrelin secretion patterns in women with binge eating to contribute to understanding factors that may be involved in the development and maintenance of binge eating. Method: Participants were 112 women with transdiagnostic binge eating using DSM-IV- criteria, who were recruited for the Binge Eating Psychotherapy Study (BEP), and 50 healthy control women. All participants completed the CANTABeclipse neuropsychological battery, the National Adult Reading Test-Revised and the Trail Making Test. A biological assessment of the neurohormone ghrelin, (total ghrelin and C-ghrelin), insulin and glucose after an overnight fast and then following an oral glucose challenge test was completed on 51 of the women with binge eating disorders and 46 of the heathy control women. Results: Key findings were: - No significant impairments were found in neuropsychological functioning in the domains of pre-morbid intelligence, attention, visuo-spatial perception and memory, and set-shifting in women with binge eating compared with women who do not binge eat. - Women with binge eating disorder performed more poorly on a test of verbal recall compared to women with bulimia nervosa and women who do not binge eat. -Neuropsychological functioning was not associated with higher rates of eating disorder severity, depression, anxiety or impulsivity in women with binge eating. - Total ghrelin secretion is blunted in women with binge eating compared with women who do not binge eat. - Some aspects of eating disorder pathology including frequency of binges, frequency of vomiting, extent of exercise, perfectionism and drive for thinness were associated with total ghrelin levels. - Ghrelin levels were not associated with neuropsychological functioning in women with binge eating. Conclusion: Results of the current study suggest that neuropsychological functioning is not significantly impaired in women with binge eating, and if relative impairments are present they are unlikely to have a major impact on overall functioning. However, it is possible that the specific neuropsychological tests used may have been of insufficient difficulty to demonstrate differences in this population. Significant differences in ghrelin secretion were found in women with binge eating suggesting that this may be a useful area to study further in order to understand binge eating. Further research in this area is warranted, with a particular focus on exploring factors which may contribute to the variation in ghrelin secretion among binge eating individuals.