Anorexia Nervosa-What Has Changed in the State of Knowledge about Nutritional Rehabilitation for Patients over the Past 10 Years? A Review of Literature

Gut Microbiome Changes in Anorexia Nervosa: A Comprehensive Review

Anorexia nervosa (AN) remains a challenging condition in psychiatric management and its pathogenesis is not yet fully understood. An imbalance in the gut microbiota composition may contribute to its pathophysiology. This review aims to explore the link between the human gut microbiota and AN (objective 1) or refeeding syndrome in AN (objective 2). The online databases MEDLINE and PsycINFO were searched for relevant studies. A total of 14 studies met the inclusion and exclusion criteria and only answered objective 1. A total of 476 AN patients, 554 healthy-weight (HC) controls, and 0 patients with other psychiatric disorders were included. Compared to HC, there were consistently reduced abundances of Faecalibacterium prausnitzii and Roseburia inulinivorans, and increased Methanobrevibacter smithii, in AN patients. Changes in alpha diversity were inconsistent, while beta diversity increased in four of six studies. Our model suggests that an imbalance in gut microbiota composition leads to reduced short-chain fatty acids, contributing to a proinflammatory state in AN, which is also common in other psychiatric comorbidities. Microbial changes may also contribute to the semistarvation state through endocrine changes and altered energy utilization.

Early evaluation of a DBT-informed online intervention for people with eating disorders

OBJECTIVES

Eating disorders (EDs) have a worldwide prevalence of 7.8%, with towering mortality rates and high healthcare costs. The current recommended treatment for EDs principally works by directly targeting ED thoughts and behaviours, but recovery rates are low. A multifaceted link between difficulties with emotions and EDs is now widely established, and newer third-wave therapies that aim to address these underlying emotion difficulties are promising. The current study piloted an online emotion self-help intervention which was co-developed with clinicians and people with lived experienced of EDs. The intervention aimed to specifically address difficulties with emotion identification and regulation, as well as unhelpful beliefs about emotions, which are believed to give rise to and maintain ED thoughts and behaviours.

METHOD

We recruited 39 people with self-reported EDs to test this intervention over a one-week period. Our participants were asked to complete a series of questionnaires measuring emotion processes and psychopathology on Day 1 (T1) before being given access to the intervention. Participants were then asked to practice the newly acquired skills for seven days, before taking the same questionnaires on Day 9 (T2). We also asked participants to qualitatively report on their experience of the intervention.

RESULTS

We found significant improvements in ED psychopathology (ED-15), depression (PHQ-9), and anxiety (GAD-7) pre- to post-intervention, with medium to large effect sizes. All our emotion variables namely alexithymia (TAS-20), difficulties regulating emotions (DERS-SF), and unhelpful beliefs about emotions (EBQ) also showed significant changes post-intervention with medium to large effect sizes. Most importantly, changes in emotion regulation processes were linked to improved eating psychopathology. The qualitative analysis corroborated this finding, highlighting how the intervention helped them form new beliefs about emotions, which helped them reduce ED behaviours.

DISCUSSION

Significant improvements in emotion processing and regulations, as well as psychopathology, along with positive qualitative feedback, suggest that the intervention effectively met its aims of increasing awareness of the link between emotions and eating psychopathology, providing help to identify and regulate emotions, and normalising emotional experiences. While our results are promising, further research is required to assess its effectiveness longer term and in clinical settings.

Characterization of refeeding protocols for under 18 years old hospitalized patients with anorexia nervosa: A systematic review

PURPOSE

To characterize and compare, through descriptive analysis, existing refeeding protocols for under 18 years old hospitalized patients with anorexia nervosa (AN).

METHODS

This is a systematic review of PubMed, Cochrane, SciELO, Lilacs and BVS databases, without search period restriction. Studies were selected in accordance with pre-defined eligibility criteria and according to the Population, Intervention, Comparator, Outcome and Study Design (PICOS).

RESULTS

Twenty articles out of 412 found complied with PICOS eligibility criteria and were included in the final review. Most of the studies were observational or retrospective and 80% were published in the last decade. Large variability in relation to sample size, refeeding protocols and length of stay were observed between studies.

CONCLUSION

All included studies had several methodological limitations and heterogeneous designs, making it difficult to establish conclusive guidelines regarding the most adequate and effective refeeding protocol for under 18 years old hospitalized patients with AN. Prospective trials are necessary to straight compare standard refeeding protocols for this population.

Collaborative dietetic and psychological care in Interprofessional Enhanced Cognitive Behaviour Therapy for adults with Anorexia Nervosa: a novel treatment approach

Clinical practice guidelines for anorexia nervosa (AN) and atypical anorexia nervosa recommend treatment from a team including a mental health professional and a dietitian. To date, however, AN treatment models such as Enhanced Cognitive Behaviour Therapy (CBT-E) seldom include dietitians and have low to moderate treatment efficacy. Given interprofessional approaches to healthcare have been shown to improve treatment outcomes and enhance patient and clinician satisfaction, formalising collaborative dietetic and psychological treatment may be a feasible strategy to improve treatment outcomes and the patient and clinician experience of treatment. Moreover, malnutrition is a serious consequence of AN, and dietitians are considered experts in its diagnosis and treatment. This paper proposes a novel treatment approach, Interprofessional Enhanced Cognitive Behaviour Therapy (CBT-IE), an adaptation of CBT-E where dietitians deliver content related to malnutrition and dietary restraint and mental health professionals deliver content related to cognitive and behavioural change. The rationale for developing CBT-IE, treatment structure, and future research directions is discussed.

Ketamine and Zinc: Treatment of Anorexia Nervosa Via Dual NMDA Receptor Modulation

Anorexia nervosa is a disorder associated with serious adverse health outcomes, for which there is currently considerable treatment ineffectiveness. Characterised by restrictive eating behaviours, distorted body image perceptions and excessive physical activity, there is growing recognition anorexia nervosa is associated with underlying dysfunction in excitatory and inhibitory neurometabolite metabolism and signalling. This narrative review critically explores the role of N-methyl-D-aspartate receptor-mediated excitatory and inhibitory neurometabolite dysfunction in anorexia nervosa and its associated biomarkers. The existing magnetic resonance spectroscopy literature in anorexia nervosa is reviewed and we outline the brain region-specific neurometabolite changes that have been reported and their connection to anorexia nervosa psychopathology. Considering the proposed role of dysfunctional neurotransmission in anorexia nervosa, the potential utility of zinc supplementation and sub-anaesthetic doses of ketamine in normalising this is discussed with reference to previous research in anorexia nervosa and other neuropsychiatric conditions. The rationale for future research to investigate the combined use of low-dose ketamine and zinc supplementation to potentially extend the therapeutic benefits in anorexia nervosa is subsequently explored and promising biological markers for assessing and potentially predicting treatment response are outlined.