Purging syndromes (PS), including Purging Disorder (PD) and Bulimia Nervosa (BN), are eating disorders marked by purging and associated with severe health complications, disability, and increased suicide risk/mortality. While data support the concurrent validity of PD and BN as separate syndromes, limited longitudinal data exist describing the outcome of PD to support the predictive validity of this distinction. If outcome and predictors of outcome differ between PD and BN, then PD should be added as a separate diagnosis in future editions of the DSM. If PD and BN do not differ in outcome or predictors of outcome, then BN's definition should be expanded to include PD. Lack of evidence-based treatments for PD and poor treatment outcomes in BN suggest that a better understanding of predictors of outcome is needed to develop more efficacious treatments. Importantly, an improved understanding requires integration of psychological and biological factors in models of eating disorder maintenance. The proposed Ruth L. Kirschstein National Research Service Award (NRSA) is a thirty-month program of training and research focused on translational clinical neuroscience that will prepare the applicant to pursue a research career dedicated to understanding risk and maintenance factors for eating disorders. In addition to completing requirements of the applicant's doctoral program, the proposed training program will inform the proposed longitudinal study through graduate training in neuroscience coursework, a lab rotation, and instruction in hormonal assays, advanced training in statistical methods, ethics, and grant-writing, and statistical mentorship. A community-based sample of 219 women (88 PD; 131 BN) will be recruited from two prior NIMH funded studies. Participants will be invited to complete assessments a mean (SD) of 10.89 (3.21) years after initial assessments.
The specific aims are to 1) examine the predictive validity of the distinction between PD and BN, 2) evaluate cognitive, cognitive-affective, behavioral, and physiological predictors of PS outcome in order to inform future treatment development, and 3) evaluate if predictors of outcome (Aim 2) differ between PD and BN in exploratory analyses.
For Aim 1, the applicant hypothesizes that PD will be associated with better outcome compared to BN and diagnostic distinctions between disorders will demonstrate longitudinal stability.
For Aim 2, the applicant predicts that more severe shape concerns (a self-reported cognitive factor), more frequent loss of control eating (a self- reported cognitive-affective factor), greater eating episode size (a behavioral factor), lowe leptin concentrations (a physiological factor), and blunted postprandial cholecystokinin response (a physiological factor) will be associated with worse outcome. This study will inform the conceptualization of PD and BN and may identify multiple points of opportunity for intervention. Completing the proposed training program and research will prepare the applicant to conduct cutting-edge translational research necessary to improve the understanding and treatment of eating disorders.
Eating disorders are associated with significant impairment, increased mortality, and poor treatment outcomes. This training program will provide the applicant with integrated training in basic neuroscience and clinical science through coursework, a neuroscience lab rotation, and instruction in hormonal assays, and by supporting a research project that will identify cognitive, cognitive-affective, behavioral, and physiological predictorsof eating disorder outcome. This project will provide information crucial for improving the understanding and treatment of eating disorders and prepare the applicant for a career dedicated to understanding eating disorder risk and maintenance.
