Treatment resistance in eating disorders: a question of uncertain targets or insufficient personalization?

Although there is a plethora of clinical guidelines which aim to describe the current status of treatment for eating disorders because the underpinning research evidence is weak, their power to have a marked impact on clinical practice is limited. The recent German guidelines (Resmark, Herpertz, Herpertz-Dahlmann, & Zeeck, 2019) have taken a big picture perspective including an overview of other guidelines and built their recommendation upon newer techniques such as a network meta-analysis in order to synthesize the evidence. Despite these sophisticated approaches, there remains much uncertainty because of the weak foundations. There are many controversies in the field such as; what are the relevant outcomes? and how does the research evidence sit within the three legs of evidence-based practice? (Sackett, Rosenberg, Gray, Haynes, & Richardson, 1996). Often, the input from patients and carer input, and even that from clinicians, is missing.

An example of a missing piece of the evidence-based practice puzzle has been added in the form of two new papers describing feedback from patients and carers about treatment for adolescents with anorexia nervosa (Mitrofan et al., 2019), specifically family-based therapy (FBT) (Wufong, Rhodes, & Conti, 2019). The feedback from carers questions the practice of allocating responsibility for re-feeding and weight restoration to parents within an adversarial framework in which parents are empowered to do battle with an externalized eating disorder, which can leave those families who ‘fail’ in this task dispirited and guilty. Furthermore, this feedback also questions the initial sole focus on eating, deferring a consideration of a more personalized formulation including predisposing and perpetuating factors until later phases of treatment. These other aspects of psychological distress (depression, OCD, ASD, social anxiety, etc) have been found to moderate the response to treatment and, therefore, perhaps merit earlier consideration.

The phased framework of FBT follows the ‘agnostic to aetiology’ stance, which was part of the initial conceptualization of family-based treatment over 40 years ago. Academics in the field might hope that their endeavours to understand the illness and produce ideas for targeted treatments might be integrated more into current treatments. The papers in this edition aim to fill some of these gaps. For the most part these focus on the dilemmas posed in the treatment of adults in which there is a large variation in clinical presentation from those in the early onset phase to those with a more severe enduring form of eating. This diverse clinical presentation requires a personalised approach to treatment. Adults with an eating disorder are comfortable about providing feedback and have more choice about what treatments they wish to take up. For example, early pharmacological studies had a particularly poor uptake.

The first part of this special edition considers the possibilities of a more personalized approach. One example is the possible association between autistic spectrum conditions and anorexia nervosa (Treasure, 2013; Westwood & Tchanturia, 2017), building on an insight first made by Gillberg (1983) and later illustrated within the meticulous longitudinal tracking of the cohort of cases ascertained at age 15 (Nielsen et al., 2015). The paper by Kinnaird, Norton, Stewart, and Tchanturia (2019) invited feedback about treatment and services from patients with this form of comorbidity. There are suggestions that a more personalized formulation treatment approach might be needed for this sub-group. The other example explores the possibility of using neuroscience (such as EEG responses) to define explanatory models, such as bottom up changes in attention or top down controlling mechanisms (Chami et al., 2019). This probably is still ‘work in progress’.

The next sections illustrate more of a shared partnership between academics, clinicians, and patients and carers. Currently, there is little evidence that medication contributes to the management of eating disorders. Nevertheless, medication is widely used in clinical practice for those with a treatment resistant/severe enduring form of illness. The chapter on shared decision-making considers how this issue can be negotiated (Himmerich, Bentley, Lichtblau, Brennan, & Au, 2019). Medication is often of value in other forms of psychiatric conditions when abnormal behaviours are driven by inner voices. Patients with eating disorder often refer to their anorexic voice. The paper by Aya, Ulusoy, and Cardi (2019) is a systematic review of what is known about this aspect of phenomenology in people with eating disorders. Not only does this review suggest that it may be useful to consider this as a key outcome measure, but it also opens the door to new targeted treatments.

The issue of developing a shared approach between the three elements needed for evidence-based practice is illustrated in the next section. Albano, Hodsoll, Kan, Lo Coco, and Cardi (2019) and colleagues present a systematic review of blended approaches to treatment. At one time the idea of including self-help materials in the treatment of anorexia nervosa was discounted because of the patient’s ambivalence about treatment (Wilson & Zandberg, 2012). However, others have taken the opposite stance, which is to manage the ambivalence with a collaborative approach in which information about the illness is shared and possible treatment strategies are offered in the form of experimental approaches to be tried. The conclusion from the systemic review was that this form of treatment was more acceptable with less drop out and more efficient, although there was no appreciable impact on standard outcomes.

Isolation is a key aspect of treatment resistant anorexia nervosa (McKnight & Boughton, 2009). Families can become fragmented and experience ‘burn out’ when their efforts to provide support appear to be spurned or unhelpful. Furthermore, the secondary adverse consequences of chronic starvation and stress upon social cognition have profound interpersonal effects (Treasure & Schmidt, 2013). ECHOMANTRA is a hybrid form of blended intervention which provides information and skills training for both carers and patients so that they can collaborate on managing the tricky transition from inpatient to community care (Adamson et al., 2019). Not only does this allow inpatient care to become more efficient and effective, but carers themselves are less burdened by the illness and utilize a greater range of helpful strategies.

The loneliness of people who progress to the severe enduring stage of illness is a modifiable target of treatment. Russell, Mulvey, Bennett, Donnelly, and Frig (2019) distil the clinical experience needed to care for people at this stage using a mixture of harm reduction strategies entwined with hope that recovery is possible. Although there are many brands of therapy that have been scrutinized under the spotlight of a randomized control trial when the active ingredients of such trials are considered, there is a high degree of similarity, as shown in the paper by Leonidas, Nazar, Munguía & dos Santos (2019) . It is to be hoped that a clarification of processes can lead to the development of a tool box of strategies that can be matched to the form and stage of the illness.

Acknowledgements

Thanks to Laura Eid in the preparation of this article.