A scoping review of psychological interventions and outcomes for avoidant and restrictive food intake disorder (ARFID)

Avoidant Restrictive Food Intake Disorder (ARFID)-Looking beyond the eating disorder lens?

Avoidant Restrictive Food Intake Disorder (ARFID) was first included as a diagnostic category in 2013, and over the past 10 years has been adopted by the international eating disorder community. While greater awareness of these difficulties has increased identification, demand and enabled advocacy for clinical services, the heterogeneous nature of ARFID poses unique challenges for eating disorder clinicians and researchers. This commentary aims to reflect on some of these challenges, focussing specifically on the risk of viewing ARFID through an eating disorder lens. This includes potential biases in the literature as most recent research has been conducted in specialist child and adolescent eating disorder clinic settings, bringing in to question the generalisability of findings to the broad spectrum of individuals affected by ARFID. We also consider whether viewing ARFID predominantly through an eating disorder lens risks us as a field being blinkered to the range of effective skills our multi-disciplinary feeding colleagues may bring. There are opportunities that may come with the eating disorder field navigating treatment pathways for ARFID, including more joined up working with multi-disciplinary colleagues, the ability to transfer skills used in ARFID treatment to individuals with eating disorder presentations, and most notably an opportunity to provide more effective treatment and service pathways for individuals with ARFID and their families. However, these opportunities will only be realised if eating disorder clinicians and researchers step out of their current silos.

Conceptualizing avoidant/restrictive food intake disorder via an executive functioning lens

Avoidant/restrictive food intake disorder (ARFID) is a heterogeneous disorder wherein restrictive eating is primarily attributed to non-shape/weight-based reasons (e.g., sensory sensitivity) that empirical research continues to explore. Mounting evidence suggests that ARFID often presents alongside neurodevelopmental diagnoses (NDs) or divergent neurodevelopment broadly. Executive functioning (EF) differences often characterize divergent neurodevelopmental trajectories. Additionally, restrictive eating in anorexia nervosa has been conceptualized as related to EF factors (e.g., set shifting). Given the neurodevelopmental phenotype that may be associated with ARFID and the role of EF in anorexia nervosa, this paper proposes EF as a potentially important, yet understudied factor in ARFID pathology. We posit that various observed ARFID behavioral/cognitive tendencies can be conceptualized in relation to EF differences. We contextualize commonly observed ARFID presentations within "core" EF components (i.e., cognitive flexibility, working memory, inhibitory control), leading to hypotheses about EF in ARFID. Finally, we offer additional considerations/directions for future research on EF in ARFID. Increased research on EF in ARFID is needed to consider this potential common factor in the etiology and maintenance of this heterogeneous disorder. We aim to promote further consideration of EF in ARFID etiology, maintenance, and treatment-outcome research. PUBLIC SIGNIFICANCE: This article proposes that aspects of executive functioning (EF) may play a role in the onset and maintenance of avoidant/restrictive food intake disorder (ARFID), although this notion is largely untested by existing research. Further research on the role of EF in ARFID may assist with refining models and treatments for this heterogeneous disorder.

Clinical characteristics, treatment course and outcome of adults treated for avoidant/restrictive food intake disorder (ARFID) at a tertiary care eating disorders program

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) is now recognized as a feeding/eating disorder that affects individuals across the lifespan, but research on ARFID in general and particularly in adults remains limited. The purpose of this study was to describe the demographic and clinical characteristics of adults with ARFID seeking treatment at a tertiary care eating disorders program, and to describe the course and outcomes of treatment at three levels of care-inpatient, intensive outpatient, and outpatient individual therapy.

METHOD

This retrospective chart review study examined the charts of 42 patients who received treatment for ARFID between April 2020 and March 2023. Following diagnostic assessment, patients were referred to either inpatient treatment, intensive outpatient treatment, or outpatient individual therapy. All three levels of care involved individual cognitive behaviour therapy. Inpatients typically transitioned to one of the outpatient treatments as part of a continuous care plan. We examined demographic and clinical characteristics, treatment length and completion, and changes in key indicators during treatment.

RESULTS

Patients were diverse with respect to demographics (e.g., 62% cisgender women; 21% cisgender men; 17% transgender, non-binary, or other gender) and comorbid concerns (e.g., 43% had neurodevelopmental disorders; > 50% had mood and anxiety disorders; 40% had posttraumatic stress disorder [PTSD]; 35% had medical conditions impacting eating/digestion). Most patients presented with more than one ARFID maintaining mechanism (i.e., lack of appetite/interest, sensory sensitivities, and/or fear of aversive consequences of eating). Treatment completion rates and outcomes were good. On average, patients showed significant improvement in impairment related to their eating disorder, and those who were underweight significantly improved on BMI and were not underweight at end of treatment.

DISCUSSION

These findings add to the literature by indicating that ARFID patients are commonly male or have diverse gender identities, and have high rates of neurodevelopmental, mood, anxiety, and gastrointestinal disorders. We also found high rates of PTSD. The findings show promise for treatment outcomes across the continuum of care. Next steps in ARFID treatment and research include incorporating ARFID-specific assessments into routine care, and ongoing research investigating the efficacy and effectiveness of treatments such as CBT-AR.