RESEARCH ARTICLE Brain white matter microstructure in obese women with binge eating disorder Nara Mendes Estella 1 | Liana Guerra Sanches 2 | Mara Fernandes Maranh~ ao 1 | Marcelo Queiroz Hoexter 1 | Ulrike Schmidt 3 | Iain C. Campbell 3 | Edson Amaro Jr. 2 | Angélica Medeiros Claudino 1 1 Eating Disorder Program (PROATA), Department of Psychiatry, Universidade Federal de S~ ao Paulo (UNIFESP), S~ ao Paulo, Brazil 2 Hospital Israelita Albert Einstein, S~ ao Paulo, Brazil 3 Institute of Psychiatry, Psychology and Neuroscience, King's College London (KCL), London, UK Correspondence Nara Mendes Estella, PROATA— Department of Psychiatry, Universidade Federal de S~ ao Paulo (UNIFESP), Rua Maj. Maragliano, 241, S~ ao Paulo 04017- 030, SP, Brazil. Email: naramendes@alumni.harvard.edu Funding information Conselho Nacional de Desenvolvimento Científico e Tecnológico, Grant/Award Number: 448058/2014-6; Coordenaç~ ao de Aperfeiçoamento de Pessoal de Nível Superior, Grant/Award Number: 001; Fundaç~ ao de Amparo à Pesquisa do Estado de S~ ao Paulo, Grant/Award Number: 2014/04258-5 Abstract Objective: Research on potential brain circuit abnormalities in binge eating disorder (BED) is limited. Here, we assess white matter (WM) microstructure in obese women with BED. Method: Diffusion tensor imaging data were acquired, and tract-based spatial statistics used to examine WM in women with BED who were obese (n = 17) compared to normal-weight (NWC) (n = 17) and to women who were obese (OBC) (n = 13). Body mass index (BMI) was a covariate in the analyses. Results: The BED group (vs. NWC) had greater axial diffusion (AD) in the for- ceps minor, anterior thalamic radiation, superior and inferior longitudinal fas- ciculus, that is, in pathways connecting fronto-limbic regions. Microstructures differences in AD between the BED and OBC groups were seen in fronto-lim- bic pathways extending to temporoparietal pathways. The BED (vs. OBC) group had greater fractional anisotropy in the forceps minor and greater AD in the superior longitudinal fasciculus, cingulate gyrus, and corpus callosum, consistent with fronto-tempoparietal pathways. Conclusion: Women with BED show WM alterations in AD in fronto-limbic and parietal pathways that are important in decision-making processes. As BMI was a covariate in the analyses, alterations in BED may be part of the pathology, but whether they are a cause or effect of illness is unclear. KEYWORDS binge eating disorder, diffusion tensor imaging, eating disorders, neuroimaging, obesity 1 | INTRODUCTION Binge eating disorder (BED) is a diagnosis in DSM-5: a key symptom is binge eating, characterized by ingestion of a large amount of food, the experience of loss of con- trol over eating, and significant distress. Approximately 40% of people with BED are obese (Hudson, Hiripi, Pope, & Kessler, 2007), and 80% are reported to meet criteria for another psychiatric disorder (Kessler et al., 2013). Roughly 50% of people with BED report significant role impairment, for example, work productivity is less in obese individuals with binge-eating, than in those with obesity alone (Striegel, Bedrosian, & Wang, 2012). Treat- ment of BED often combines psychological and pharma- cological interventions (Ghaderi et al., 2018): these can help individuals manage eating disorder symptoms, but tend to have little impact on weight loss (Hay et al., 2014). Received: 20 November 2019 Revised: 9 May 2020 Accepted: 13 June 2020 DOI: 10.1002/erv.2758 Eur Eat Disorders Rev. 2020;1–11. wileyonlinelibrary.com/journal/erv © 2020 John Wiley & Sons, Ltd and Eating Disorders Association 1