Implicit attitudes toward dieting and thinness distinguish fat‐phobic and non‐fat‐phobic anorexia nervosa from avoidant/restrictive food intake disorder in adolescents

Abstract

Objective The majority of individuals with anorexia nervosa (AN) have a fat‐phobic (FP‐AN) presentation in which they explicitly endorse fear of weight gain, but a minority present as non‐fat‐phobic (NFP‐AN). Diagnostic criteria for avoidant/restrictive food intake disorder (ARFID) specifically exclude fear of weight gain. Differential diagnosis between NFP‐AN and ARFID can be challenging and explicit endorsements do not necessarily match internal beliefs. Method Ninety‐four adolescent females (39 FP‐AN, 13 NFP‐AN, 10 low‐weight ARFID, 32 healthy controls [HC]) completed implicit association tests (IATs) categorizing statements as pro‐dieting or non‐dieting and true or false (questionnaire‐based IAT), and images of female models as underweight or normal‐weight and words as positive or negative (picture‐based IAT). We used the Eating Disorder Examination to categorize FP‐ versus NFP‐AN presentations. Results Individuals with FP‐AN and NFP‐AN demonstrated a stronger association between pro‐dieting and true statements, whereas those with ARFID and HCs demonstrated a stronger association between pro‐dieting and false statements. Furthermore, while all groups demonstrated a negative implicit association with underweight models, HC participants had a significantly stronger negative association than individuals with FP‐AN and NFP‐AN. Discussion Individuals with NFP‐AN exhibited a mixed pattern in which some of their implicit associations were consistent with their explicit endorsements, whereas others were not, possibly reflecting a minimizing response style on explicit measures. In contrast, individuals with ARFID demonstrated implicit associations consistent with explicit endorsements. Replication studies are needed to confirm whether the questionnaire‐based IAT is a promising method of differentiating between restrictive eating disorders that share similar clinical characteristics.

Fat-Phobic and Non-Fat-Phobic Anorexia Nervosa: A Conjoint Analysis on the Importance of Shape and Weight

“…Yet, looking at the part-worth utilities, it is of note that NFP-AN participants' preference for weight maintenance vs. weight gain became apparent, which was even more pronounced than those of participants with FP-AN, still tentatively suggesting that contrary to their self-report, they may experience fear of weight gain. These results are in line with the findings on adolescents and young women with NFP-AN (Izquierdo et al, 2019) and could reflect an explicit denial of fear of weight gain while facing an unconscious fear of weight gain at the same time. It is also of note that participants with NFP-AN put a significant higher relative importance on success in job or school while they showed a significantly lower relative importance on the factor interpersonal/belonging than HC.…”

“…Furthermore, while individuals with NFP-AN might exhibit lower psychopathology (Forbush and Wildes, 2017), they also present with higher treatment drop-outs, lower remission rates, and lower insight into their condition (Santonastaso et al, 2009). The latter could be one possible explanation for their denial of fear of weight gain, besides having divergent rationales for food restriction (Becker et al, 2009;Lee et al, 2012) and minimizing or denying shape and weight concerns (Izquierdo et al, 2019). Thus, an identification and diagnosis of individuals with NFP-AN are essential to adequately shape treatment for this patient group, potentially with a less strong focus on alteration of body image disturbance.…”

“…However, there have been calls for the use of performance-based measures in NFP-AN to determine whether fear of weight gain may be present on an implicit level even if not explicitly endorsed (Thomas et al, 2013). The only study aiming to implicitly assess fear of weight gain in AN made use of implicit association tests (IATs) (Izquierdo et al, 2019). Results revealed that adolescents with and without reported fear of weight gain showed similar implicit biases toward dieting and thinness, but those with NFP-AN scored significantly lower on the explicit EDI-3 Drive for Thinness subscale than individuals with FP-AN.…”

Introduction to a special issue on child and adolescent feeding and eating disorders and avoidant/restrictive food intake disorder

“…In prototypical cases, differential diagnosis is straightforward, but in other cases (e.g., a low‐weight adolescent girl who denies shape and weight concerns yet eats very little) the distinction is less clear. Izquierdo et al () compared children and adolescents with fat‐phobic AN, non‐fat‐phobic AN, and ARFID to healthy controls on a behavioral task, which revealed stronger implicit associations between pro‐dieting and true statements in both AN groups compared to the ARFID and control groups, who themselves showed stronger associations between pro‐dieting and false statements. It is possible that, in the future, performance‐based tasks could represent a helpful tool for differential diagnosis in ambiguous cases of restrictive eating disorders.…”

“…For independence of the review process, Ruth Striegel Weissman served as the editor for three manuscripts included in this Special Issue (Bryant‐Waugh et al, ; Eddy et al, ; Izquierdo et al, ).…”