A pilot study exploring the effect of repetitive transcranial magnetic stimulation (rTMS) treatment on cerebral blood flow and its relation to clinical outcomes in severe enduring anorexia nervosa

[Effects of non-invasive neuromodulation on the cognitive profile of people with anorexia nervosa: A scoping review]

BACKGROUND

The use of non-invasive neuromodulation is emerging in the treatment of anorexia nervosa. Despite promising results, further research is needed to improve our understanding of these techniques and to adapt interventions to this population. As anorexia nervosa is associated with several cognitive difficulties and cerebral anomalies, the aim of the present study was to summarize the available data on the effects of non-invasive neuromodulation on the neuropsychological profile of people with anorexia nervosa.

METHOD

A scoping review was conducted by searching in PsycINFO, PubMed and CINAHL databases to systematically identify relevant studies published between 1994 and 2023 on the treatment of anorexia nervosa with repetitive transcranial magnetic stimulation, transcranial direct current stimulation or neurofeedback electroencephalogram.

RESULTS

Seventeen articles were included, including 12 on repetitive transcranial magnetic stimulation, four on transcranial direct current stimulation and one on neurofeedback electroencephalogram. Of these, only three studies included a neuropsychological measure to assess the impact of neuromodulation on participants' cognitive functions.

CONCLUSIONS

Including detailed neuropsychological measures in clinical trials of non-invasive neuromodulation is highly recommended and appears essential to improve our understanding of these techniques and optimize their efficacy in the treatment of anorexia nervosa.

Severe enduring anorexia nervosa (SE-AN) treatment options and their effectiveness: a review of literature

INTRODUCTION

 For nearly 20% of patients diagnosed with Anorexia Nervosa (AN), the eating disorder (ED) is prolonged and becomes long-lasting. It has been reported that patients diagnosed with Severe Enduring Anorexia Nervosa (SE-AN) have worse ED symptoms, higher rates of lifetime hospitalization, and lower psychosocial well-being compared to patients with shorter disease duration.

OBJECTIVES

 This review aims to describe the treatments proposed to date and their effectiveness on SE-AN-related outcomes.

METHODS

 We conducted a PubMed search for studies addressing the issue of treatment approach to SE-AN adults, that were published between 2003 and 2023, peer-reviewed, written in the English language, and available in full-text. Next, we inductively created relevant macro-themes by synthesizing the data from the included articles.

RESULTS

 Of 251 PubMed studies, 25 articles were considered for data extraction, all published between 2003 and 2022. We identified three macro-themes. The first macro-theme, "Psychotherapy", mostly takes into consideration treatment effectiveness of cognitive behavioral therapy (CBT). Various reports determined its greater effectiveness compared to Specialist Supportive Clinical Management (SSCM), and one study proved that outpatient CBT is a valid alternative to hospitalization. The second one involves "Pharmacological Treatments". Research on dronabinol, a synthetic orexigenic cannabinoid, antipsychotics (in particular, olanzapine and haloperidol), and ketamine showed some mixed results regarding the often-complementary areas of weight gain and improvement in ED-related symptoms. Regarding the third macro-theme, "Brain Stimulation Therapies," such as Repetitive Transcranial Magnetic Stimulation (rTMS) and Deep Brain Stimulation (DBS), we found promising results in improving ED-related psychological traits (such as mood and anxiety), affective regulation, and quality of life. However, we have observed divergent results regarding outcome measures such as BMI and weight gain.

CONCLUSIONS

 SE-AN patients are predicted to encounter both medical complications and psychological distress of increasing severity that will inevitably affect their quality of life; to our knowledge, research evidence on treatment options for SE-AN remains limited, and the methodological quality of studies is generally low. These findings denote the need to focus future research efforts on effective treatment strategies specific to long-lasting EDs.

EDIFY (Eating Disorders: Delineating Illness and Recovery Trajectories to Inform Personalised Prevention and Early Intervention in Young People): project outline

EDIFY (Eating Disorders: Delineating Illness and Recovery Trajectories to Inform Personalised Prevention and Early Intervention in Young People) is an ambitious research project aiming to revolutionise how eating disorders are perceived, prevented and treated. Six integrated workstreams will address key questions, including: What are young people's experiences of eating disorders and recovery? What are the unique and shared risk factors in different groups? What helps or hinders recovery? How do the brain and behaviour change from early- to later-stage illness? How can we intervene earlier, quicker and in a more personalised way? This 4-year project, involving over 1000 participants, integrates arts, design and humanities with advanced neurobiological, psychosocial and bioinformatics approaches. Young people with lived experience of eating disorders are at the heart of EDIFY, serving as advisors and co-producers throughout. Ultimately, this work will expand public and professional perceptions of eating disorders, uplift under-represented voices and stimulate much-needed advances in policy and practice.

Can neuroimaging measures differentiate the disease course of anorexia nervosa? A systematic review

Anorexia nervosa (AN) entails many uncertainties regarding the clinical outcome, due to large heterogeneity in the disease course. AN is associated with global decrease in brain volumes and altered brain functioning during acute illness. However, it is unclear whether structural and functional brain alterations can predict clinical outcome. We aimed to systematically review the predictive value of volumetric and functional brain outcome measures of structural and functional brain magnetic resonance imaging (MRI) on the disease course of AN. Four databases (Embase, Medline, Psycinfo, and Cochrane Central Register) were systematically searched. A total of 15 studies (structural MRI: n = 6, functional MRI: n = 9) were reviewed. In total 464 unique AN patients, and 328 controls were included. Follow-up time ranged between 1 and 43 months. Structural neuroimaging studies showed that lower brain volumes of the cerebellum, subcortical grey matter, and cortical white matter at admission predicted a worse clinical outcome. A smaller increase of the anterior cingulate cortex volume in the early phase of the disease predicted a worse clinical outcome. Lower overall gyrification, and a higher clustering coefficient predicted a worse clinical outcome. Functional MRI studies showed that frontal, parietal and temporal activity during task-based algorithms predicted follow-up body mass index, although results were bidirectional possibly due to the large heterogeneity in methodological approaches. Neuroimaging measures may predict the clinical outcome of AN. However, there is a lack of replication studies. Future studies are needed to validate the prognostic utility of neuroimaging measures in AN patients, and should harmonize demographic, clinical and neuroimaging features in order to enhance comparability.

Cerebral blood flow changes induced by high-frequency repetitive transcranial magnetic stimulation combined with cognitive training in Alzheimer's disease

Background and purpose

Hypoperfusion of the posterior cingulate cortex (PCC) and precuneus has consistently been reported in patients with Alzheimer's disease (AD). Repetitive transcranial magnetic stimulation (rTMS) combined with cognitive training (COG) is effective in alleviating the symptoms of patients with mild AD. This study investigated the effects of rTMS-COG therapy on cerebral blood flow (CBF), with a special interest in the PCC/precuneus, and whether observed CBF changes are associated with changes in neuropsychological assessments in AD.

Materials and methods

Twenty-one patients with mild or moderate AD were randomly divided into real rTMS (n = 11) and sham treatment (n = 10) groups, both combined with COG. Neuro-navigated 10 Hz rTMS was used to stimulate the left dorsolateral prefrontal cortex (DLPFC) and then the left lateral temporal lobe (LTL) for 20 min each day for 4 weeks in the real rTMS group. All patients with AD underwent neuropsychological assessment, pseudo-continuous arterial spin labeling, and structural 3D T1-weighted MRI before treatment (T0), immediately after treatment (T1), and 4 weeks after treatment (T2). CBF in the precuneus, PCC, and stimulation targets at the region-of-interest (ROI) level, as well as whole-brain CBF changes at the voxel level, were compared between the two groups at three timepoints.

Results

rTMS-COG therapy revealed significant group × time interactions for the Mini-Mental State Examination (F = 5.339, p = 0.023, η² = 0.433) and activities of daily living (F = 5.409, p = 0.039, η² = 0.436) scores. The regional CBF in the precuneus showed a significant group × time interaction (F = 5.833, p = 0.027, η² = 0.593). For voxel-level analysis, a significant group main effect was found in the left limbic lobe cluster, with the maximal peak in the left parahippocampus (p < 0.001, uncorrected, peak at [-16 -8 -24]). Simple effects analysis indicated that rTMS-COG therapy induced a decrease in CBF in the precuneus at T1 (p = 0.007) and an increase in the left parahippocampus at T2 (p=0.008). CBF decrease in the precuneus was correlated with better cognitive function immediately after treatment (T1) (r =-0.732, p=0.025).

Conclusion

Neuropsychological assessments showed immediate and long-term effects on cognitive function and activities of daily living after rTMS-COG therapy. CBF changes induced by high-frequency rTMS-COG therapy are region-dependent, showing immediate effects in the precuneus and long-term effects in the left parahippocampus. These results provide imaging evidence to understand the underlying neurobiological mechanism for the application of rTMS-COG in AD.

Insight Into the Effects of Clinical Repetitive Transcranial Magnetic Stimulation on the Brain From Positron Emission Tomography and Magnetic Resonance Imaging Studies: A Narrative Review

Repetitive transcranial magnetic stimulation (rTMS) has been proposed as a therapeutic tool to alleviate symptoms for neurological and psychiatric diseases such as chronic pain, stroke, Parkinson’s disease, major depressive disorder, and others. Although the therapeutic potential of rTMS has been widely explored, the neurological basis of its effects is still not fully understood. Fortunately, the continuous development of imaging techniques has advanced our understanding of rTMS neurobiological underpinnings on the healthy and diseased brain. The objective of the current work is to summarize relevant findings from positron emission tomography (PET) and magnetic resonance imaging (MRI) techniques evaluating rTMS effects. We included studies that investigated the modulation of neurotransmission (evaluated with PET and magnetic resonance spectroscopy), brain activity (evaluated with PET), resting-state connectivity (evaluated with resting-state functional MRI), and microstructure (diffusion tensor imaging). Overall, results from imaging studies suggest that the effects of rTMS are complex and involve multiple neurotransmission systems, regions, and networks. The effects of stimulation seem to not only be dependent in the frequency used, but also in the participants characteristics such as disease progression. In patient populations, pre-stimulation evaluation was reported to predict responsiveness to stimulation, while post-stimulation neuroimaging measurements showed to be correlated with symptomatic improvement. These studies demonstrate the complexity of rTMS effects and highlight the relevance of imaging techniques.

'My dad was like "it's your brain, what are you doing?"': Participant experiences of repetitive transcranial magnetic stimulation treatment in severe enduring anorexia nervosa

Objective

Repetitive transcranial magnetic stimulation (rTMS) is a promising emerging treatment for anorexia nervosa (AN). However, to date, patients' views and experiences of this treatment have not been fully explored. To assess these, we integrated a qualitative study into a feasibility randomised controlled trial of rTMS in individuals with severe enduring AN.

Method

Twenty‐nine (of 34) trial participants contributed to this study. Semi‐structured interviews were conducted 3‐months following the completion of rTMS treatment (4‐months post‐randomisation), prior to unblinding. Transcripts were analysed using content analysis.

Results

rTMS was deemed an acceptable but time‐consuming treatment. Many emphasised how their lives had changed to some extent during, but mainly after treatment by making them more positive, open‐minded, flexible and willing to try new things in relation to their AN and other aspects of their lives.

Conclusions

These qualitative data will be valuable in shaping participant information, recruitment and planning of future large‐scale trials of rTMS in AN.

Trial Registration

ISRCTN14329415, registered 23rd July 2015, https://www.isrctn.com/ISRCTN14329415

This study is the first to systematically explore participants' experiences of repetitive transcranial magnetic stimulation (rTMS) treatment for severe enduring anorexia nervosa (AN), as part of a randomised controlled feasibility trial.

Participants expressed that rTMS was an acceptable but time‐consuming treatment. Many participants who received real rTMS described positive changes in relation to AN and quality of life.

Findings from this qualitative study will help to shape future research of rTMS treatment for AN.

Neuromodulation and Eating Disorders

PURPOSE OF REVIEW

We review recent evidence on the use of neuromodulation for treating eating disorders (EDs), including anorexia nervosa, bulimia nervosa and binge eating disorder. We evaluate studies on (a) modern non-invasive methods of brain stimulation, such as transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), (b) electroconvulsive therapy (ECT) and (c) more invasive techniques, including deep brain stimulation (DBS).

RECENT FINDINGS

Most reports on the clinical applications of neuromodulation in EDs are limited to case studies, case series and small clinical trials. The majority have focused on severe, enduring and hard-to-treat cases of AN. In this population, data suggest that both rTMS and DBS have therapeutic potential and are safe and acceptable. High-quality clinical trials in different ED populations are needed which investigate different stimulation methods, sites and parameters, the use of neuromodulation as stand-alone and/or adjunctive treatment, as well as the mechanisms of action.