Structural brain differences in recovering and weight-recovered adult outpatient women with anorexia nervosa

Abstract

Background Anorexia nervosa is a complex psychiatric illness that includes severe low body weight with cognitive distortions and altered eating behaviors. Brain structures, including cortical thicknesses in many regions, are reduced in underweight patients who are acutely ill with anorexia nervosa. However, few studies have examined adult outpatients in the process of recovering from anorexia nervosa. Evaluating neurobiological problems at different physiological stages of anorexia nervosa may facilitate our understanding of the recovery process. Methods Magnetic resonance imaging (MRI) images from 37 partially weight-restored women with anorexia nervosa (pwAN), 32 women with a history of anorexia nervosa maintaining weight restoration (wrAN), and 41 healthy control women were analyzed using FreeSurfer. Group differences in brain structure, including cortical thickness, areas, and volumes, were compared using a series of factorial f-tests, including age as a covariate, and correcting for multiple comparisons with the False Discovery Rate method. Results The pwAN and wrAN cohorts differed from each other in body mass index, eating disorder symptoms, and social problem solving orientations, but not depression or self-esteem. Relative to the HC cohort, eight cortical thicknesses were thinner for the pwAN cohort; these regions were predominately right-sided and in the cingulate and frontal lobe. One of these regions, the right pars orbitalis, was also thinner for the wrAN cohort. One region, the right parahippocampal gyrus, was thicker in the pwAN cohort. One volume, the right cerebellar white matter, was reduced in the pwAN cohort. There were no differences in global white matter, gray matter, or subcortical volumes across the cohorts. Conclusions Many regional structural differences were observed in the pwAN cohort with minimal differences in the wrAN cohort. These data support a treatment focus on achieving and sustaining full weight restoration to mitigate possible neurobiological sequela of AN. In addition, the regions showing cortical thinning are similar to structural changes reported elsewhere for suicide attempts, anxiety disorders, and autistic spectrum disorder. Understanding how brain structure and function are related to clinical symptoms expressed during the course of recovering from AN is needed.

Structural brain changes in severe and enduring anorexia nervosa: A multimodal magnetic resonance imaging study of gray matter volume, cortical thickness, and white matter integrity

“…Studies in weight-recovered AN (wr-AN) patients may help address this issue. In adult wr-AN patients, GMV change has been shown to be reversible (Brodrick et al, 2021;Kaufmann et al, 2020;Nickel et al, 2018). Moreover, CT changes have been shown to be reversible for the most part, although decreases in the superior frontal cortex can persist (Kaufmann et al, 2020).…”

Neural processes related to negative self‐concept in adult and adolescent anorexia nervosa

“…Immaturity of the superior longitudinal fasciculus, the last whitematter tract to reaches maturity, has been specifically associated with negatively biased self-referential processing in major depressive disorder (MDD), in conjunction with reduced activation of the precuneus (Pisner et al, 2019). Relative to healthy comparison, cortical thinning of frontal and cingulate neural regions, areas important in social cognition, has been observed for partially weight restored adult women with AN but not fully weight restored adult women with AN (Brodrick et al, 2021). Both nutritional rehabilitation and experiencing positive social interactions during early adulthood may be necessary to develop a positive sense of selfidentity; problems with this process may promote the negative self-concept, shame and body distortions that characterise eating disorders.…”

Biased and inflexible interpretations of ambiguous social situations: Associations with eating disorder symptoms and socioemotional functioning

“…Our sample's low symptom severity (see Section 4.1) may explain why we found no association between eating disorder symptoms and inflexible interpretations. More severe symptoms may have nutritional sequalae that interfere with cognitive flexibility (Miles et al, 2020), and neurological sequelae that impact social cognition (Brodrick et al, 2021). Moreover, more severe symp- et al, 2018, 2020).…”

“…Our sample's low symptom severity (see Section 4.1) may explain why we found no association between eating disorder symptoms and inflexible interpretations. More severe symptoms may have nutritional sequalae that interfere with cognitive flexibility (Miles et al, 2020), and neurological sequelae that impact social cognition (Brodrick et al, 2021). Moreover, more severe symptoms may elicit reactions from close others (anxiety/depression, accommodating behaviors; see Treasure et al, 2020) that perpetuate interpersonal stress and impact social emotion regulation in ways not captured by the present study.…”

“…This social feedback may be particularly salient in the context of interpersonal difficulties that limit other opportunities for positive social interaction. Over time, however, eatingdisorder-related behaviors may erode social cognition (Cardi et al, 2017; for example, reducing cortical volume in brain areas associated with social cognition, including the inferior frontal gyrus and right pars opercularis, see: Brodrick et al, 2021;King et al, 2015) and strain social relationships (for example, encouraging social withdrawal secondary to avoidance of social situations involving eating; Christensen & Haynos, 2020). This process would leave individuals with eating disorder tendencies increasingly isolated and reliant on disordered eating for emotion regulation (Arcelus, Haslam, Farrow, & Meyer, 2013).…”