Amygdalar functional connectivity during resting and evoked pain in youth with functional abdominal pain disorders

Exploring Psychological Factors and Brain Alterations in Functional Anorectal Pain Patients: Insights From Multimodal Magnetic Resonance Imaging Investigations

BACKGROUND

Functional anorectal pain (FAP) is classified as one of the disorders of gut-brain interaction (DGBI). It involves the impairments of anorectal afferents and disrupted gut-brain communication. However, neuroimaging studies focused on FAP are lacking.

METHODS

A total of 25 FAP patients and 18 healthy controls (HC) underwent structural magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), resting-state functional MRI (rs-fMRI) scans, and collection of demographic data, mental health assessment scales and pain assessment questionnaires. Voxel-based morphometry (VBM), tract-based spatial statistics (TBSS), regional homogeneity (ReHo), and amplitude of low-frequency fluctuations (ALFF) were utilized to analyze the imaging data. Correlation analyses were conducted to explore the relationships between the neuroimaging findings and clinical symptoms.

KEY RESULTS

Functional anorectal pain (FAP) patients exhibited higher levels of anxiety, depression scores and lower sleep quality compared to HC. VBM analysis revealed increased gray matter volume (GMV) in the bilateral fusiform, right parahippocampal, bilateral inferior temporal gyrus (ITG), and decreased GMV in the right superior frontal gyrus (SFG), left middle frontal gyrus (MFG), bilateral inferior frontal gyrus (IFG), left Calcarine, bilateral middle occipital gyrus (MOG), left middle temporal gyrus (MTG) in FAP patients. TBSS analysis showed decreased fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF), anterior thalamic radiation (ATR), and forceps minor in the FAP patients. Additionally, increased ALFF in the right cerebellum and increased ReHo in the right MFG were observed in the FAP patients.

CONCLUSIONS AND INFERENCES

These findings showed a worse psychological condition and suggested neuroanatomical and neurofunctional alterations associated with pain processing, emotion regulation, and cognitive control in FAP patients.

Heterogeneity in Pancreatitis: Recognizing Heterogeneity and Its Role in the Management of Pancreatitis Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

ABSTRACT

Both the clinical management and study of recurrent acute pancreatitis and chronic pancreatitis are complicated by significant heterogeneity in the etiology, mechanisms, symptoms, and complications of pancreatitis. The National Institutes of Diabetes and Digestive and Kidney Disease recently convened a workshop to address current knowledge and knowledge gaps in the field. Preclinical models that better replicate human disease are important for development of new therapies. Pain is often the most common and most difficult symptom to treat, as the causes are multifactorial and effective treatment may vary depending on whether pain is neuropathic or nociceptive in origin, and the placebo effect can complicate evaluation of the efficacy of medical and procedural interventions. Novel technologies like functional magnetic resonance imaging and virtual reality may offer novel means for assessing and treating pain, respectively. Clinical trial designs will need to consider best approaches to addressing the heterogeneity of chronic pancreatitis, including careful attention to designing eligibility criteria, and establishing accepted and validated core outcomes criteria for the field. The latter may be informed by consensus in pain research. Recruitment of participants into clinical trials has been challenging, often requiring multiple centers. Establishment of a clinical trials network would facilitate greater opportunities for therapeutic trials in pancreatitis.

Study protocol for a pilot clinical trial to understand neural mechanisms of response to a psychological treatment for pain and anxiety in pediatric functional abdominal pain disorders (FAPD)

BACKGROUND

Functional abdominal pain disorders (FAPD) are the most common chronic pain conditions of childhood and are made worse by co-occurring anxiety. Our research team found that the Aim to Decrease Pain and Anxiety Treatment (ADAPT), a six-session coping skills program using cognitive behavioral therapy strategies, was effective in improving pain-related symptoms and anxiety symptoms compared to standard care. In follow-up, this current randomized clinical trial (RCT) aims to test potential neural mechanisms underlying the effect of ADAPT. Specifically, this two-arm RCT will explore changes in amygdalar functional connectivity (primary outcome) following the ADAPT protocol during the water loading symptom provocation task (WL-SPT). Secondary (e.g., changes in regional cerebral blood flow via pulsed arterial spin labeling MRI) and exploratory (e.g., the association between the changes in functional connectivity and clinical symptoms) outcomes will also be investigated.

METHODS

We will include patients ages 11 to 16 years presenting to outpatient pediatric gastroenterology care at a midwestern children's hospital with a diagnosis of FAPD plus evidence of clinical anxiety based on a validated screening tool (the Generalized Anxiety Disorder-7 [GAD-7] measure). Eligible participants will undergo baseline neuroimaging involving the WL-SPT, and assessment of self-reported pain, anxiety, and additional symptoms, prior to being randomized to a six-week remotely delivered ADAPT program plus standard medical care or standard medical care alone (waitlist). Thereafter, subjects will complete a post assessment neuroimaging visit similar in nature to their first visit.

CONCLUSIONS

This small scale RCT aims to increase understanding of potential neural mechanisms of response to ADAPT.

TRIAL REGISTRATION

ClinicalTrials.gov registration: NCT03518216.

A developmental framework for understanding the influence of sex and gender on health: Pediatric pain as an exemplar

Sex differences are a robust finding in many areas of adult health, including cardiovascular disease, psychiatric disorders, and chronic pain. However, many sex differences are not consistently observed until after the onset of puberty. This has led to the hypothesis that hormones are primary contributors to sex differences in health outcomes, largely ignoring the relative contributions of early developmental influences, emerging psychosocial factors, gender, and the interaction between these variables. In this paper, we argue that a comprehensive understanding of sex and gender contributions to health outcomes should start as early as conception and take an iterative biopsychosocial-developmental perspective that considers intersecting social positions. We present a conceptual framework, informed by a review of the literature in basic, clinical, and social science that captures how critical developmental stages for both sex and gender can affect children's health and longer-term outcomes. The literature on pediatric chronic pain is used as a worked example of how the framework can be applied to understanding different chronic conditions.

Brain stimulation targets for chronic pain: Insights from meta-analysis, functional connectivity and literature review

Noninvasive brain stimulation (NIBS) techniques have demonstrated their potential for chronic pain management, yet their efficacy exhibits variability across studies. Refining stimulation targets and exploring additional targets offer a possible solution to this challenge. This study aimed to identify potential brain surface targets for NIBS in treating chronic pain disorders by integrating literature review, neuroimaging meta-analysis, and functional connectivity analysis on 90 chronic low back pain patients. Our results showed that the primary motor cortex (M1) (C3/C4, 10-20 EEG system) and prefrontal cortex (F3/F4/Fz) were the most used brain stimulation targets for chronic pain treatment according to the literature review. The bilateral precentral gyrus (M1), supplementary motor area, Rolandic operculum, and temporoparietal junction, were all identified as common potential NIBS targets through both a meta-analysis sourced from Neurosynth and functional connectivity analysis. This study presents a comprehensive summary of the current literature and refines the existing NIBS targets through a combination of imaging meta-analysis and functional connectivity analysis for chronic pain conditions. The derived coordinates (with integration of the international electroencephalography (EEG) 10/20 electrode placement system) within the above brain regions may further facilitate the localization of these targets for NIBS application. Our findings may have the potential to expand NIBS target selection beyond current clinical trials and improve chronic pain treatment.