Naturalistic symptom trajectories of atypical anorexia nervosa, anorexia nervosa, and bulimia nervosa in a prospective cohort study of United States college students.

OBJECTIVE: Research on the natural course of symptoms of atypical anorexia nervosa (AN) relative to AN and bulimia nervosa (BN) is limited yet needed to inform nosology and improve understanding of atypical AN. This study aimed to 1) characterize trajectories of eating disorder and internalizing (anxiety, depression) symptoms in college students with and without a history of atypical AN, AN, and BN; and 2) compare sex and race/ethnicity distributions across groups. METHOD: United States college students who participated in Spit for Science™, a prospective cohort study, were classified as having a history of atypical AN (n = 125), AN (n = 160), BN (n = 617), or as non-eating-disorder controls (NCs, n = 5876). Generalized and linear mixed-effects models assessed group differences in eating and internalizing symptom trajectories, and logistic regression compared groups on sex and race/ethnicity distributions. RESULTS: Atypical AN participants demonstrated elevated eating disorder and internalizing symptoms compared to NCs during college, but less severe symptoms than AN and BN participants. Although all eating disorder groups showed signs of improvement in fasting and driven exercise, purging and depression remained elevated. Atypical AN participants showed increasing anxiety and stable binge-eating trajectories compared to AN and/or BN participants. The atypical AN group comprised significantly more people of color than the AN group. DISCUSSION: Findings underscore that atypical AN is a severe psychiatric disorder. As atypical AN may present as less severe than AN and BN and disproportionately affects people of color, clinicians should be mindful of biases that could delay diagnosis and care. PUBLIC SIGNIFICANCE: College students with histories of atypical AN, AN, and BN demonstrated improvements in fasting and driven exercise and stable purging and depression levels. Atypical AN students showed worsening anxiety and stable binge-eating trajectories compared to favorable changes among AN and BN students. A higher percentage of atypical AN (vs. AN) students were people of color. Findings may improve the detection of atypical AN in college students.

A randomized, controlled pilot study of positive affect treatment adapted for anorexia nervosa.

OBJECTIVE: Novel treatments for adults with anorexia nervosa (AN) are sorely needed. Although psychological interventions have been developed for AN, none have been identified as superior to one another or nonspecific treatments. Common comorbidities (e.g., mood and anxiety disorders) are rarely targeted in AN treatments, possibly impairing long-term clinical improvement. AN is associated with reward processing dysfunctions paralleling those identified in affective disorders; however, few treatments directly target these processes. METHOD: We adapted Positive Affect Treatment, a neuroscience-informed behavioral treatment developed for affective disorders, to the treatment of AN (PAT-AN). Adults with AN (N = 20) were randomized to 20 weeks of PAT-AN or waitlist to investigate the feasibility, acceptability, preliminary efficacy, and target engagement (on reward mechanisms) of PAT-AN. RESULTS: PAT-AN demonstrated strong retention (100%) and acceptability ratings (M = 5.67-5.95 on a 7-point scale). BMI (p = .006) and eating disorder symptoms (p < .001) improved over PAT-AN sessions. The PAT-AN group showed medium to large pre-to-post-treatment improvements in BMI, eating disorder symptoms and impairment, depressive and anxiety symptoms, and some reward indices (ds = .56-.87); changes were largely sustained at 3-month follow-up. Waitlist showed negligible changes (ds < .20) on nearly all measures. DISCUSSION: PAT-AN holds promise as an innovative treatment with capability to simultaneously improve eating disorder symptoms, affective symptoms, and underlying reward mechanisms. Findings should be interpreted cautiously due to small sample size and permitted concurrent enrollment in other treatments. Future, larger-scale research is warranted to establish the efficacy of PAT-AN. PUBLIC SIGNIFICANCE: This study provided a preliminary evaluation of Positive Affect Treatment for anorexia nervosa (PAT-AN), a novel, neuroscience-informed treatment aimed at increasing rewarding life experiences outside of one's eating disorder. Initial results suggest that PAT-AN is considered acceptable and may alleviate eating disorder, depressive, and anxiety symptoms. Therefore, this study presents promising data on a treatment that may hold potential for improving the lives of individuals with this disorder.