Optimizing relapse prevention and changing habits (REACH+) in anorexia nervosa

Distributive randomization: a pragmatic fractional factorial design to screen or evaluate multiple simultaneous interventions in a clinical trial

BACKGROUND

In some medical indications, numerous interventions have a weak presumption of efficacy, but a good track record or presumption of safety. This makes it feasible to evaluate them simultaneously. This study evaluates a pragmatic fractional factorial trial design that randomly allocates a pre-specified number of interventions to each participant, and statistically tests main intervention effects. We compare it to factorial trials, parallel-arm trials and multiple head-to-head trials, and derive some good practices for its design and analysis.

METHODS

We simulated various scenarios involving 4 to 20 candidate interventions among which 2 to 8 could be simultaneously allocated. A binary outcome was assumed. One or two interventions were assumed effective, with various interactions (positive, negative, none). Efficient combinatorics algorithms were created. Sample sizes and power were obtained by simulations in which the statistical test was either difference of proportions or multivariate logistic regression Wald test with or without interaction terms for adjustment, with Bonferroni multiplicity-adjusted alpha risk for both. Native R code is provided without need for compiling or packages.

RESULTS

Distributive trials reduce sample sizes 2- to sevenfold compared to parallel arm trials, and increase them 1- to twofold compared to factorial trials, mostly when fewer allocations than for the factorial design are possible. An unexpectedly effective intervention causes small decreases in power (< 10%) if its effect is additive, but large decreases (possibly down to 0) if not, as for factorial designs. These large decreases are prevented by using interaction terms to adjust the analysis, but these additional estimands have a sample size cost and are better pre-specified. The issue can also be managed by adding a true control arm without any intervention.

CONCLUSION

Distributive randomization is a viable design for mass parallel evaluation of interventions in constrained trial populations. It should be introduced first in clinical settings where many undercharacterized interventions are potentially available, such as disease prevention strategies, digital behavioral interventions, dietary supplements for chronic conditions, or emerging diseases. Pre-trial simulations are recommended, for which tools are provided.

Testing the role of associative learning in evidence-based treatments for anorexia nervosa

Treatments for anorexia nervosa (AN) remain ineffective for many patients. Processes that can account for differential treatment outcomes remain mostly unknown. We propose that the field test the role of associative learning in current psychological treatments. We hold that this line of research could yield actionable information for understanding non-response and improving long-term outcomes. To make this argument, we define associative learning and outline its proposed role in understanding psychiatric disorders and their treatment. We then briefly review data exploring associative learning in AN. We argue that associative learning processes are implicitly implicated in existing treatments; by this rationale, baseline differences in learning may interfere with treatment response. Finally, we outline future research to test our hypotheses. Altogether, future research aimed at better understanding how associative learning may contribute to AN symptom persistence has the potential to inform novel directions in intervention research. PUBLIC SIGNIFICANCE: There is a pressing need to improve outcomes in treatments for anorexia nervosa (AN). We propose that individual differences in associative learning-the ability to form and update associations between cues, contexts, behaviors, and outcomes-may account for differential response to existing treatments. Undertaking this research could provide an understanding of how current treatments work and inform new approaches for those who may be at risk of poor outcomes.

The next stages of treatment-oriented research: Commentary on Wade et al. (2023)

Treatments for eating disorders have established benefits; yet, current psychotherapies focus specifically on the cognitions and behaviors of the eating disorder. Wade et al. (2023) propose that the myriad symptoms and disorders that occur together with eating disorders merit specific attention in treatment research protocols. We seek to amplify the authors' call to take a fresh look at the characterization of eating disorders, and the need for treatment research to consider both the role of symptoms that occur as part and parcel of an eating disorder (such as mood, anxiety, and obsessionality) and the role of co-occurring disorders (such as obsessive-compulsive disorder and substance use disorders). We discuss additional aspects in the care of patients with eating disorders that were beyond the scope of Wade et al., such as the impact of systems of care, and consideration of medication trials. We propose that current research priorities (mechanism-based treatment development, transdiagnostic symptoms, and patient perspectives) can be leveraged to advance treatment research and develop a systematic approach to evaluation and treatment planning.

Perspectives on relapse prevention following intensive treatment of anorexia nervosa: A focus group study

OBJECTIVE

Including the perspectives of individuals with lived experience of mental health issues is a critical step in research and treatment development. Focus groups with patients with a history of treatment for anorexia nervosa (AN) were conducted in anticipation of a clinical trial of Relapse Prevention and Changing Habits (REACH+).

METHODS

Seven female adults (23-51 years) who had previously received inpatient treatment for AN, now in remission, participated in one of two semistructured focus groups. Rapid qualitative analysis was used to examine participants' contributions and identify common topics.

RESULTS

Transcript analysis yielded three topics related to relapse prevention: (1) recovery aids, including a sense of agency in treatment decisions and finding new interests/passions, (2) recovery hindrances, such as lack of access to care, and (3) identification of members of support system. Aspects of REACH+ received positive feedback, such as continuity of care from the inpatient setting and the use of telehealth. Viewpoints differed with respect to the helpfulness of obtaining patient weights in treatment. The REACH+ online platform received positive comments regarding content and usability, as well as suggestions for additional content.

DISCUSSION

Qualitative feedback from patients with a history of AN highlighted the value of engaging patients in their own treatment decisions, as well as in treatment design and innovation. Within this small group, there were differences of opinion about treatment components, specifically weight assessment, that suggest the need for further data. User-centered design provides opportunities to improve the acceptability and, therefore, dissemination of novel treatments.

PUBLIC SIGNIFICANCE

Relapse prevention is a critical treatment need for patients with anorexia nervosa, as this illness too often follows a protracted course. There are challenges in both obtaining specialized care and in retaining patients in treatment. Here, patient perspectives on these challenges offer input to allow for optimization of relapse prevention treatment. Shared decision-making may be particularly valuable to support an individual's sense of agency and engagement in care.

A pilot randomized controlled trial of a cognitive-behavioral therapy guided self-help mobile app for the post-acute treatment of anorexia nervosa: A registered report

INTRODUCTION

Relapse following acute treatment for anorexia nervosa (AN) is common. Evidence suggests cognitive-behavioral therapy (CBT) may be useful in the post-acute period, but few patients have access to trained providers. mHealth technologies have potential to increase access to high-quality care for AN, including in the post-acute period. The aim of this study is to estimate the preliminary feasibility and effectiveness of a CBT-based mobile intervention plus treatment as usual (TAU), offered with and without an accompanying social networking feature.

METHOD

In the current pilot randomized controlled trial, women with AN who have been discharged from acute treatment in the past 2 months (N = 90) will be randomly assigned to a CBT-based mobile intervention plus treatment as usual (TAU), a CBT-based mobile intervention including social networking plus TAU, or TAU alone. We will examine feasibility, acceptability, and preliminary effectiveness of the three conditions in terms of reducing eating disorder psychopathology, reducing frequency of eating disorder behaviors, achieving weight maintenance, reducing depression and suicidal ideation, and reducing clinical impairment. We will examine rehospitalization and full recovery rates in an exploratory fashion. We will also examine whether the mobile intervention and social networking feature change the proposed targets and whether changes in targets are associated with benefit, as well as conduct exploratory analyses to identify within-mobile intervention predictors and moderators of outcome.

DISCUSSION

Ultimately, this research may lead to increased access to evidence-based treatment for individuals with AN and prevention of the extreme negative consequences that can result from this serious disorder.

PUBLIC SIGNIFICANCE

Relapse after acute treatment for anorexia nervosa is common, and few patients have access to trained providers to support them following acute care. This study will pilot a coached mobile app, including a social networking component, for this population. If ultimately successful, our approach could greatly increase access to evidence-based treatment for individuals with anorexia nervosa and ultimately prevent the extreme negative consequences that can result from this serious disorder.