Visual mapping of body image disturbance in anorexia nervosa reveals objective markers of illness severity

Accurate Prediction of Three-Dimensional Humanoid Avatars for Anthropometric Modeling

Objective

To evaluate the hypothesis that anthropometric dimensions derived from a person's manifold-regression predicted three-dimensional (3D) humanoid avatar are accurate when compared to their actual circumference, volume, and surface area measurements acquired with a ground-truth 3D optical imaging method. Avatars predicted using this approach, if accurate with respect to anthropometric dimensions, can serve multiple purposes including patient metabolic disease risk stratification in clinical settings.

Methods

Manifold regression 3D avatar prediction equations were developed on a sample of 570 adults who completed 3D optical scans, dual-energy X-ray absorptiometry (DXA), and bioimpedance analysis (BIA) evaluations. A new prospective sample of 84 adults had ground-truth measurements of 6 body circumferences, 7 volumes, and 7 surface areas with a 20-camera 3D reference scanner. 3D humanoid avatars were generated on these participants with manifold regression including age, weight, height, DXA %fat, and BIA impedances as potential predictor variables. Ground-truth and predicted avatar anthropometric dimensions were quantified with the same software.

Results

Following exploratory studies, one manifold prediction model was moved forward for presentation that included age, weight, height, and %fat as covariates. Predicted and ground-truth avatars had similar visual appearances; correlations between predicted and ground-truth anthropometric estimates were all high (R2s, 0.75-0.99; all p < 0.001) with non-significant mean differences except for arm circumferences (%D ~ 5%; p < 0.05). Concordance correlation coefficients ranged from 0.80-0.99 and small but significant bias (p < 0.05 - 0.01) was present with Bland-Altman plots in 13 of 20 total anthropometric measurements. The mean waist to hip circumference ratio predicted by manifold regression was non-significantly different from ground-truth scanner measurements.

Conclusions

3D avatars predicted from demographic, physical, and other accessible characteristics can produce body representations with accurate anthropometric dimensions without a 3D scanner. Combining manifold regression algorithms into established body composition methods such as DXA, BIA, and other accessible methods provides new research and clinical opportunities.

Embodiment of underweight and normal-weight avatars affects bodily self-representations in anorexia nervosa

Body image distortion (BID) is a crucial aspect of anorexia nervosa (AN), leading to body overestimation, dissatisfaction, and low self-esteem. BID significantly influences the onset, maintenance, and relapse of the pathology. We assessed whether a Full Body Illusion (FBI) using under and normal-weight avatars' bodies affects perceptual body image and body schema estimations in both individuals with anorexia nervosa (AN) and healthy controls (HC). After each embodiment procedure, we asked participants to estimate the width of their hips (Perceptual Body Image Task) and the minimum aperture width of a virtual door necessary to pass through it (Body Schema Task). Additionally, we asked participants to rate the avatars in terms of self-similarity, attractiveness, and implicit disgust (i.e., pleasant/unpleasant body odour). Whereas participants with AN (N = 26) showed changes in body schema estimations after embodying the normal-weight avatar, no changes were found in HC (N = 25), highlighting increased bodily self-plasticity in AN. Notably, individuals with AN rated the normal weight avatar as the most similar to their real body, which was also considered the least attractive and the most repulsive. These ratings correlated with BID severity. Furthermore, at the explicit level, all participants reported feeling thinner than usual after embodying the underweight avatar. Overall, our findings suggest that BID in AN engages multiple sensory channels (from visual to olfactory) and components (from perceptual to affective), offering potential targets for innovative non-invasive treatments aimed at modifying flexible aspects of body representation.

Dynamic relationships among feeling fat, fear of weight gain, and eating disorder symptoms in an eating disorder sample

Feeling fat and fear of weight gain are key cognitive-affective symptoms that are theorized to maintain eating disorders (EDs). Little research has examined the dynamic relationships among feeling fat, fear of weight gain, emotions, cognitions, and ED behaviors. Furthermore, it is unknown if these relations vary by ED diagnosis (e.g., anorexia nervosa (AN) vs other ED). The current study (N = 94 ED participants; AN n = 64) utilized ecological momentary assessments collected four times a day for 18 days (72 timepoints) asking about feeling fat, fear of weight gain, emotions (i.e., anxiety, guilt), cognitions (i.e., feelings of having overeaten, thoughts about dieting), and ED behaviors (i.e., vomiting, diuretic/laxative use, excessive exercise, body checking, self-weighing, binge-eating, restriction) at stressful timepoints (contemporaneous [mealtime], and prospective/temporal [next-meal]). Multilevel modeling was used to test for between and within-person associations. Higher feeling fat and fear of weight gain independently predicted higher next-meal emotions (i.e., anxiety, guilt), cognitions (i.e., feelings of having overeaten, thoughts about dieting, fear of weight gain, feeling fat), and ED behaviors (i.e., body checking, self-weighing [feeling fat]). There were relationships in the opposite direction, such that some emotions, cognitions, and ED behaviors prospectively predicted feeling fat and fear of weight gain, suggesting existence of a reciprocal cycle. Some differences were found via diagnosis. Findings pinpoint specific dynamic and cyclical relationships among feeling fat, fear of weight gain, and specific ED symptoms, and suggest the need for more research on how feeling fat, fear of weight gain and cognitive-affective-behavioral aspects of ED operate. Future research can test if treatment interventions targeted at feeling fat and fear of weight gain may disrupt these cycles.

Evidence-Based Assessments for Transdiagnostic Eating Disorder Symptoms: Guidelines for Current Use and Future Directions

Eating disorders are severe and often chronic mental illnesses that are associated with high impairment and mortality rates. Recent estimates suggest that eating disorder prevalence rates are on the rise, indicating an increased need for accurate assessment and detection. The current review provides an overview of transdiagnostic eating disorder assessments, including interview, self-report, health and primary care screeners, and technology-based and objective assessments. We focused on assessments that are transdiagnostic in nature and exhibit high impact in the field. We provide recommendations for how these assessments should be used in research and clinical settings. We also discuss considerations that are crucial for assessment, including the use of a categorical versus dimensional diagnostic framework, assessment of eating disorders in related fields (i.e., anxiety and depression), and measurement-based care for eating disorders. Finally, we provide suggestions for future research, including the need for more research on short transdiagnostic screeners for use in health care settings, standardized assessments for ecological momentary assessment, development of state-based assessment of eating disorder symptoms, and consideration of assessment across multiple timescales.

Sex-dependent clinical presentation, body image, and endocrine status in long-term remitted anorexia nervosa

OBJECTIVE

Although anorexia nervosa (AN) in males has recently gained attention, knowledge of its psychological and physiological outcomes is still scarce. We explore sex-specific characteristics of long-term remitted AN with respect to residual eating disorder (ED) psychopathology, body image, and endocrinology.

METHOD

We recruited 33 patients with AN in remission for at least 18 months (24 women, 9 men) and 36 matched healthy controls (HCs). Eating disorder psychopathology and body image ideals were assessed via clinical interviews, questionnaires, and an interactive 3D body morphing tool. Plasma levels of leptin, free triiodothyronine, cortisol, and sex hormones were quantified. Univariate models controlled for age and weight were used to test for the effects of diagnosis and sex.

RESULTS

Both patient groups showed residual ED psychopathology but normal weight and hormone levels relative to HCs. Male remitted patients demonstrated significantly stronger muscularity-focused body image ideals, evident in interviews, self-reports, and behavioural data, than both female patients and HCs.

CONCLUSIONS

Sex-specific body image characteristics in patients with remitted AN point towards the need to adjust test instruments and diagnostic criteria to male-specific psychopathology. In the future, sufficiently powered studies should evaluate the risk of men with AN developing muscle dysmorphia in the long term.

Neural mechanisms of perceptual and affective body-image disturbance during own-body and ideal-body estimation

Body-image disturbance is a core feature of eating disorders and can predict their development in healthy individuals. There are two components of body-image disturbance: perceptual disturbance (associated with overestimation of body size) and affective disturbance (associated with body dissatisfaction). Previous behavioral studies have hypothesized that attention to particular body parts and negative body-related emotions resulting from social pressure are associated with the respective degrees of perceptual and affective disturbance; however, the neural representations that underlie this hypothesis have not been elucidated. Thus, this study investigated the brain regions and connectivity associated with the degree of body-image disturbance. Specifically, we examined the brain activations associated with participants' estimation of the width of their actual and ideal bodies; we sought to determine which brain regions and functional connectivity from body-related visual processing regions were correlated with the degree of each component of body-image disturbance. The degree of perceptual disturbance was positively correlated with excessive width-dependent brain activations in the left anterior cingulate cortex when estimating one's body size; it was positively correlated with the functional connectivity between the left extrastriate body area and left anterior insula. The degree of affective disturbance was positively correlated with excessive width-dependent brain activation in the right temporoparietal junction and negatively correlated with functional connectivity between the left extrastriate body area and right precuneus when estimating one's ideal body size. These results support the hypothesis that perceptual disturbance is associated with attentional processing, whereas affective disturbance is associated with social processing.

Evaluation of Insight, Self-Esteem, and Body Satisfaction in Eating Disorders

ABSTRACT

We investigated insight and its relationship with the clinical characteristics in eating disorders (EDs). Thirty anorexia nervosa (AN) and 30 bulimia nervosa (BN) patients, diagnosed based on Diagnostic and Statistical Manual of Mental Disorders , Fifth Edition criteria, were evaluated with Eating Disorder Examination Questionnaire (EDE-Q), the Body Image Satisfaction Questionnaire (BISQ), Rosenberg Self-Esteem Scale (RSES), and the Brown Assessment of Beliefs Scale (BABS). There was no statistically significant difference between the AN and the BN group in clinical scale scores. Thirty percent of AN and 23.3% of BN patients showed "poor insight" according to BABS. In the whole sample, BABS scores were significantly positively correlated with the EDE-Q eating, shape, weight concern subscales, and global scores, and the RSES scores; and negatively correlated with the BISQ general appearance and trunk subscale scores. Manifestation of "poor insight" is frequent in EDs. Poor insight in EDs is associated with eating, shape and weight concerns, body dissatisfaction, and low self-esteem.

Diet, Digestion, and the Dietitian: A Survey of Clinicians' Knowledge, Attitudes and Practices to Advance the Treatment of Gastrointestinal Disturbances in Individuals with Anorexia Nervosa

Despite advances in treatment of anorexia nervosa (AN), current therapeutic approaches do not fully consider gastrointestinal disturbances (GID), often present in AN. Addressing GID, both symptoms and disorders, is likely to improve treatment adherence and outcomes in people with AN. GID are complex and are linked to a range of factors related to eating disorder symptomology and can be impacted by nutritional treatment. It is not known which dietetic practices are currently used to address GID in AN. Therefore, this survey aimed to explore the perceived knowledge, attitudes, and practices (KAP) of Australian dietitians treating AN and co-occurring GID. Seventy dietitians participated by completing an online survey. Knowledge scores were calculated based on correct responses to knowledge items (total: 12 points); and two groups were generated: higher knowledge (≥10 points, n = 31) and lower knowledge (≤9 points, n = 39). A greater proportion of dietitians with higher knowledge recognized the role of GID in pathogenesis of AN (p = 0.002) and its impact on quality of life (p = 0.013) and screened for GID (p ≤ 0.001), compared with those with lower knowledge. These results suggest that attitudes and practices toward patients presenting with AN and GID differ depending on level of knowledge. This may have important implications for treatment outcomes for individuals with AN and GID.

Perception of body size and body dissatisfaction in adults

Self-perception of body size seems to be not always in line with clinical definitions of normal weight, overweight and obesity according to Word Health Organization classification. The effect of self-perception of body size disturbances and body dissatisfaction may be the development of eating disorders, such as anorexia nervosa or binge eating disorder-a major risk factor of obesity development. Therefore, the study aimed to assess separately the perception of weight status and body size as well as body dissatisfaction in adults with normal weight, overweight and obesity. The study included 744 adults (452 women; 35.9 ± 12.4 years; 21 underweight, 326 normal weight, 221 overweight, 176 obese) referred to Metabolic Management Center and volunteers. Body size perception and body dissatisfaction were assessed based on Stunkards' Figure Rating Scale (FRS). Additionally, participants' were asked: 'Do you think you are: underweight/normal weight/overweight/obese?' to assess perception of weight status. Participants' weight and height were measured to calculate body mass index (BMI) after completing the FRS. Individuals within the overweight BMI range have rated themselves as underweight (1.4%), normal weight (30.8%) and obese (2.8%). Also individuals within the obesity BMI range have rated themselves as normal weight (2.6%), and overweight (41.6%). Compatibility of self-assessment of weight status with BMI category according to the measured values was moderate-Kappa coefficient was 0.59 (95% CI: 0.54-0.64). Underestimation of weight status was significantly more common among men than women. There were statistically significant differences in the distribution of body dissatisfaction according to the weight in both women and men. Normal-weight subjects less often than overweight and obese were dissatisfied with their own body size. The degree of body dissatisfaction was greater among women than among men. Adults subjects frequently underestimate their own weight status and body size. Women with overweight and obesity more often than men are dissatisfied with their own body size.