Cardiovascular phenotyping for personalized lifestyle treatments of chronic abdominal pain in Irritable Bowel Syndrome: A randomized pilot study

Impact of homeostatic body hydration status, evaluated by hemodynamic measures, on different pain sensitization paths to a chronic pain syndrome

Contrasting findings on the mechanisms of chronic pain and hypertension development render the current conventional evidence of a negative relationship between blood pressure (BP) and pain severity insufficient for developing personalized treatments. In this interdisciplinary study, patients with fibromyalgia (FM) exhibiting clinically normal or elevated BP, alongside healthy participants were assessed. Different pain sensitization responses were evaluated using a dynamic 'slowly repeated evoked pain' (SREP) measure, as well as static pain pressure threshold and tolerance measures. Cardiovascular responses to clino-orthostatic (lying-standing) challenges were also examined as acute re- and de-hydration events, challenging cardiovascular and cerebrovascular homeostasis. These challenges involve compensating effects from various cardiac preload or afterload mechanisms associated with different homeostatic body hydration statuses. Additionally, hair cortisol concentration was considered as a factor with an impact on chronic hydration statuses. Pain windup (SREP) and lower pain threshold in FM patients were found to be related to BP rise during clinostatic (lying) rehydration or orthostatic (standing) dehydration events, respectively. These events were determined by acute systemic vasoconstriction (i.e., cardiac afterload response) overcompensating for clinostatic or orthostatic cardiac preload under-responses (low cardiac output or stroke volume). Lower pain tolerance was associated with tonic blood pressure reduction, determined by permanent hypovolemia (low stroke volume) decompensated by permanent systemic vasodilation. In conclusion, the body hydration status profiles assessed by (re)activity of systemic vascular resistance and effective blood volume-related measures can help predict the risk and intensity of different pain sensitization components in chronic pain syndrome, facilitating a more personalized management approach.

Heart Rate Variability-An Index of the Efficacy of Complementary Therapies in Irritable Bowel Syndrome: A Systematic Review

Irritable bowel syndrome (IBS), as a functional and psychosomatic disease, reduces the quality of life and increases the risk of developing mental disorders. Deregulation of the autonomic nervous system (ANS) is one of the main causes of the disease. The objective of the present study was to identify the studies in which measurements of heart rate variability (HRV) were performed before and after therapeutic intervention, and to evaluate the effectiveness of IBS therapy in terms of a reduction of IBS symptoms and changes in autonomic tone. A systematic review of the literature was carried out in accordance with PRISMA standards. Six databases were searched for articles published before 2022: PubMed®, MEDLINE®, EBSCO, Cochrane, Scopus, and Web of Science. Inclusion criteria were experimental design, diagnosis of IBS (medical and/or diagnosis in accordance with the Rome Criteria), non-pharmacological intervention, and HRV measurement before and after the intervention. The quality of the studies was assessed by JBI Critical appraisal. In total, 455 studies were identified, of which, sixwere included in the review. Expected changes in HRV (increase in parasympathetic activity) were observed in four of the six studies (interventions studied: ear acupressure, transcutaneous auricular vagusnerve stimulation, cognitive behavioral therapy with relaxation elements, yoga). In the same studies, therapeutic interventions significantly reduced the symptoms of IBS. The present review indicated that interventions under investigation improve the efficiency of the ANS and reduce the symptoms of IBS. It is advisable to include HRV measurements as a measure of the effectiveness of interventions in IBS therapy, and to assess autonomic changes as a moderator of the effectiveness of IBS therapy.

Review article: current and future treatment approaches for pain in IBS

BACKGROUND

Abdominal pain is a core symptom of IBS and a primary driver of care seeking. Visceral hypersensitivity is a key pathophysiological mechanism and therapeutic target for pain in IBS, with components of peripheral and central sensitisation and psychological factors.

AIM

To review current and future treatment approaches specifically for the pain component of IBS.

METHODS

Pubmed search terms included combinations of irritable bowel, pain, visceral hypersensitivity, novel, new, emerging, future and advances.

RESULTS

Established non-pharmacological treatments for IBS pain include the low FODMAP diet, probiotics and psychological interventions, especially hypnotherapy. Tricyclics remain the best evidenced pharmacological approach with GCC agonists, tenapanor, lubiprostone, eluxadoline and 5HT3 antagonists second line according to patient characteristics and availability. Less well-evidenced current options include anti-spasmodics, peppermint oil, SSRIs, SNRIs, alpha 2 delta ligands, melatonin and histamine antagonists. Patients are vulnerable to iatrogenesis and harmful approaches to be avoided include opioids and unwarranted surgical interventions. For severe pain, the concept of augmentation with combined gut-brain neuromodulators and psychotherapy in a multi-disciplinary setting is considered. A plethora of molecular targets and ligands are emerging from pre-clinical studies, together with early clinical evidence for a range of pharmacological, dietary, neurostimulation and novel psychological treatment delivery methods which are reviewed. The history of such emerging approaches, however, merits both caution and optimism in equal measure.

CONCLUSIONS

Despite good in-roads and emerging options, the management of abdominal pain remains one of the biggest challenges and research priorities for patients with IBS.

Personalized behavior management as a replacement for medications for pain control and mood regulation

A lack of personalized approaches in non-medication pain management has prevented these alternative forms of treatment from achieving the desired efficacy. One hundred and ten female patients with fibromyalgia syndrome (FMS) and 60 healthy women without chronic pain were assessed for severity of chronic or retrospective occasional pain, respectively, along with alexithymia, depression, anxiety, coping strategies, and personality traits. All analyses were conducted following a ‘resource matching’ hypothesis predicting that to be effective, a behavioral coping mechanism diverting or producing cognitive resources should correspond to particular mechanisms regulating pain severity in the patient. Moderated mediation analysis found that extraverts could effectively cope with chronic pain and avoid the use of medications for pain and mood management by lowering depressive symptoms through the use of distraction mechanism as a habitual (‘out-of-touch-with-reality’) behavior. However, introverts could effectively cope with chronic pain and avoid the use of medications by lowering catastrophizing through the use of distraction mechanism as a situational (‘in-touch-with-reality’) behavior. Thus, personalized behavior management techniques applied according to a mechanism of capturing or diverting the main individual ‘resource’ of the pain experience from its ‘feeding’ to supporting another activity may increase efficacy in the reduction of pain severity along with decreasing the need for pain relief and mood-stabilizing medications.

Impact of antihypertensive treatment on resiliency to clinical pain

OBJECTIVES

Although progress has been made in the regulation of hypertension over the past decades, the USA and some other countries have faced a significant rise in incidence of chronic pain management cases during the same period. Studies of the relationship between pain and blood pressure (BP) regulations propose that these two processes may be interconnected. Studies of effects of antihypertensive treatment on pain in general and its chronification have never been reviewed.

METHODS

A narrative review of respective studies with analysis of credibility of the findings was conducted.

RESULTS

Some studies have suggested that aggressive reduction of high BP may contribute to a return in pain symptoms and may require more aggressive, long-term pain management. Other studies propose that long-term antihypertensive medication could also increase the risk for new cases of chronic pain. Pain initiates a central neuroplastic resetting of the baroreceptor activation accounting for sustained increase of BP with an adaptive 'pain-killing' or maladaptive 'pain-complication' effect associated with pain chronification, and these mechanisms may be moderated by antihypertensive medications. However, different antihypertensive drugs and nondrug treatments may diversely affect pain mechanisms at different stages of treatments.

CONCLUSION

Uncontrollable reduction of high BP in some patients with hypertension could increase the risk for chronic pain incidence and its severity. Practical recommendations in BP control should be reconsidered to take into account patients' chronic pain. Further research is needed of moderation effects of different antihypertensive manipulations on pain to improve pain management in these patients.