Descending pain modulation in irritable bowel syndrome (IBS): a systematic review and meta-analysis

Effects of Sacroiliac Joint Manipulation on Autonomic Nervous System and Lower Abdominal Pain in Women with Primary Dysmenorrhoea: A Randomized Controlled Trial

Background and Objectives: Autonomic nervous system (ANS) disorders are responsible for primary dysmenorrhea and are closely linked to the spine. This study aims to evaluate the effects of sacroiliac joint manipulation on the ANS and lower abdominal pain in women with primary dysmenorrhea and proposes an alternative treatment method. Materials and Methods: A total of 40 participants were randomly assigned; however, 35 participants remained in the final analysis after 5 dropped out; they were assigned to either the sacroiliac joint manipulation group (n = 18) or the superficial heat therapy group (n = 17). Assessments included heart rate variability (HRV), visual analogue scale (VAS) scores for lower abdominal pain, the pressure pain threshold (PPT) of the sacroiliac joint, and the Moos Menstrual Distress Questionnaire (MMDQ) at baseline and after 4 weeks. Only the VAS and MMDQ scores were reassessed after 8 weeks to evaluate the sustained effects of the treatment. Results: Changes in HRV showed improvements in ANS balance only in the sacroiliac joint manipulation group (p < 0.05). It was found to be more effective than superficial heat therapy (p < 0.05). A significant decrease in lower abdominal pain following the intervention was observed in both groups (p < 0.05), along with the sustained effects of the treatment (p < 0.05). The MMDQ scores decreased after sacroiliac joint manipulation (p < 0.05), with greater improvements compared to the superficial heat therapy (p < 0.05). Conclusions: Sacroiliac joint manipulation positively affects ANS balance and is effective in alleviating lower abdominal pain and menstruation-related symptoms, with sustained effects observed over time. Therefore, sacroiliac joint manipulation can be an effective alternative treatment for women with primary dysmenorrhea.

Extraintestinal manifestations in irritable bowel syndrome: A systematic review

Background

Irritable bowel syndrome (IBS) is characterized by abdominal pain and altered bowel habits. Further, IBS patients experience a high degree of extraintestinal symptoms.

Objectives

The aim of this review was to describe the relation between IBS and extraintestinal manifestations and mechanisms and treatments of these extraintestinal manifestations.

Design

The study was performed as a systematic review.

Data Sources and Methods

Search terms including extraintestinal manifestations or somatization and IBS were used to scrutinize for publications in Pubmed. In total, 630 publications were identified and 80 were finally included in this review.

Results

About 50% of all IBS patients have extraintestinal manifestations in addition to gastrointestinal symptoms. Somatic pain, fatigue, and sleeping disturbances are most common, and most often described in women. Both extraintestinal manifestations and psychological distress are associated with exaggerated gastrointestinal symptoms, impaired quality of life, and difficulties to treat IBS symptoms. The extraintestinal manifestations render an excess of healthcare costs. Varying etiology and pathophysiology to IBS are discussed, and many patients express a general hypersensitivity. Extraintestinal symptoms are seldom documented at clinical healthcare or included in the assessment of treatment outcomes. A good patient-physician relationship and strengthening of coping mechanisms have rendered less gastrointestinal symptoms, psychological distress, and somatization. Altered lifestyle habits may improve both gastrointestinal and extraintestinal symptoms. Pharmacological treatment, including antidepressant drugs, should be considered when lifestyle advice fails. Teamwork between different specialists and healthcare providers may be of importance in the wide range of symptoms and extraintestinal manifestations.

Conclusion

Extraintestinal manifestations are common in IBS patients and is associated with worse suffering and difficulties to treat symptoms. Evaluation and treatment of IBS patients should consider also extraintestinal manifestations and their treatment outcome. Establishment of good relationship, strengthening of coping mechanisms, and education in healthier lifestyle habits are crucial in the management of these patients.

Presence of widespread pain predicts comorbidities and treatment response in temporomandibular disorders patients

OBJECTIVES

Investigate the presence of widespread pain in a well-defined TMD group and analyze its interrelationship with various comorbidities. Also, longitudinally seek the difference in treatment response according to the presence of widespread pain.

SUBJECTS AND METHODS

The observational study involved 45 female TMD patients in their 20s. Patients were grouped into localized and widespread pain groups based on the widespread pain index (WPI ≥ 4). Clinical characteristics and levels of comorbidities were analyzed through physical examination and validated questionnaires. Differences between the groups and the power of pre-treatment WPI in predicting pre-treatment comorbidities and post-treatment pain level improvement were statistically analyzed.

RESULTS

Patients with widespread pain showed higher somatization and anxiety levels. SF-36 scores were significantly lower and more patients complained of gastrointestinal symptoms. Conventional treatment significantly reduced pain intensity in both groups but less in the widespread pain group. WPI showed significant chances to predict patients showing improvement in pain levels with treatment with a cutoff value of 4. WPI was also effective in differentiating patients that showed a higher level of somatization.

CONCLUSION

Widespread pain index could be effectively applied in differentiating those with a higher level of psychological distress and predicting TMD treatment response with further investigations into its reliability.

The Role of Descending Pain Modulation in Chronic Primary Pain: Potential Application of Drugs Targeting Serotonergic System

Chronic primary pain (CPP) is a group of diseases with long-term pain and functional disorders but without structural or specific tissue pathologies. CPP is becoming a serious health problem in clinical practice due to the unknown cause of intractable pain and high cost of health care yet has not been satisfactorily addressed. During the past decades, a significant role for the descending pain modulation and alterations due to specific diseases of CPP has been emphasized. It has been widely established that central sensitization and alterations in neuroplasticity induced by the enhancement of descending pain facilitation and/or the impairment of descending pain inhibition can explain many chronic pain states including CPP. The descending serotonergic neurons in the raphe nuclei target receptors along the descending pain circuits and exert either pro- or antinociceptive effects in different pain conditions. In this review, we summarize the possible underlying descending pain regulation mechanisms in CPP and the role of serotonin, thus providing evidence for potential application of analgesic medications based on the serotonergic system in CPP patients.

Conditioned Pain Modulation (CPM) is Reduced in Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis of CPM and the Role of Psychological Factors

This systematic review summarises evidence assessing endogenous pain inhibition in people with irritable bowel syndrome (IBS) compared with healthy controls using conditioned pain modulation (CPM) and offset analgesia (OA). Evidence regarding the role of psychological variables is also examined. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Four electronic databases were searched to retrieve studies assessing CPM or OA in adults diagnosed with IBS according to the ROME II/III criteria. Standardized mean differences were calculated for each study and a random effects model was used for meta-analysis. Eleven studies were included, 5 of which reported results on the relationship between CPM and psychological variables. None of the studies assessed OA. The risk of bias assessment found a lack of assessor blinding in all studies. The pooled effect estimate was 0.90 (95% CI, 0.40-1.40) indicating a significantly lower CPM effect in people with IBS compared with controls. This effect was reduced to 0.51 when 1 outlier was excluded from the analysis. In addition, reduced CPM responses were significantly correlated with higher anxiety (r=0.17 to 0.64), stress (r=0.63), and pain catastrophizing (r=0.38) in people with IBS; however, the evidence available was limited and the strength of these associations variable. Depression was not found to be associated with CPM in these IBS cohorts. The results of this review suggest that people with IBS, as a group, demonstrate reduced pain inhibition measured by CPM. The preliminary evidence about the association between psychological factors and CPM warrants further investigations.

From the Bottom-Up: Chemotherapy and Gut-Brain Axis Dysregulation

The central nervous system and gastrointestinal tract form the primary targets of chemotherapy-induced toxicities. Symptoms associated with damage to these regions have been clinically termed chemotherapy-induced cognitive impairment and mucositis. Whilst extensive literature outlines the complex etiology of each pathology, to date neither chemotherapy-induced side-effect has considered the potential impact of one on the pathogenesis of the other disorder. This is surprising considering the close bidirectional relationship shared between each organ; the gut-brain axis. There are complex multiple pathways linking the gut to the brain and vice versa in both normal physiological function and disease. For instance, psychological and social factors influence motility and digestive function, symptom perception, and behaviors associated with illness and pathological outcomes. On the other hand, visceral pain affects central nociception pathways, mood and behavior. Recent interest highlights the influence of functional gut disorders, such as inflammatory bowel diseases and irritable bowel syndrome in the development of central comorbidities. Gut-brain axis dysfunction and microbiota dysbiosis have served as key portals in understanding the potential mechanisms associated with these functional gut disorders and their effects on cognition. In this review we will present the role gut-brain axis dysregulation plays in the chemotherapy setting, highlighting peripheral-to-central immune signaling mechanisms and their contribution to neuroimmunological changes associated with chemotherapy exposure. Here, we hypothesize that dysregulation of the gut-brain axis plays a major role in the intestinal, psychological and neurological complications following chemotherapy. We pay particular attention to evidence surrounding microbiota dysbiosis, the role of intestinal permeability, damage to nerves of the enteric and peripheral nervous systems and vagal and humoral mediated changes.