Clinical and morphological effects of hyperbaric oxygen therapy in patients with interstitial cystitis associated with fibromyalgia

Latest insights into the pathophysiology of bladder pain syndrome/interstitial cystitis

PURPOSE OF REVIEW

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a common medical problem in both sexes affecting people of all ages. Patients might report overactive bladder symptoms with additional bladder pain at maximum bladder filling, during and after micturition. This review aims to highlight pathophysiological mechanisms associated with this disease.

RECENT FINDINGS

Latest literature exposes different pathophysiological mechanisms such as impaired urothelial barrier function, alteration of urothelial factors and cytokines, chronic inflammation, vascular lesions, neurogenic inflammation and processes in the central nervous system leading to central sensitization. According to the involved mechanisms, BPS/IC may be arranged in clusters according to the clinical phenotype thus helping in clinical decision-making and treatment. Moreover, patients with BPS/IC suffer from other comorbidities such as fibromyalgia, irritable bowel syndrome, chronic pain and functional syndromes and psychosomatic diseases making the management challenging for medical professionals.

SUMMARY

Bladder pain syndrome/interstitial cystitis is a complex heterogeneous medical condition involving different pathomechanisms leading to bladder pain and dysfunction, consequently, impairing quality-of-life in affected individuals. However, these mechanisms are still not fully understood, so that patient treatments often remain unsatisfactory. For this reason, continuing research is important to understand the underlying pathomechanisms to discover biomarkers and treatment targets eventually improving diagnostic and therapeutic measures of BPS/IC.

Multimodal therapies and strategies for the treatment of interstitial cystitis/bladder pain syndrome in Taiwan

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic disease characterized by bladder pain, frequency, and nocturia. The most common pathologies include chronic inflammation and bladder urothelium dysfunction. According to the bladder condition with or without Hunner's lesions, IC/BPS can be divided into "IC" in patients with Hunner's lesion (HIC) and "BPS" in those without Hunner's lesion (NHIC). Previous studies have reported greater central sensitization and interorgan cross-talk in patients with NHIC. Multimodal treatments have been recommended in clinical guidelines under the biopsychosocial model. The bladder-gut-brain axis has also been speculated, and multimodal therapies are necessary. Unfortunately, currently, no treatment has been reported durable for IC/BPS. Patients with IC/BPS usually experience anxiety, depression, holistic physical responses, and even threats to social support systems. The lack of durable treatment outcomes might result from inadequate diagnostic accuracy and differentiation of clinical phenotypes based on the underlying pathophysiology. Precision assessment and treatment are essential for optimal therapy under definite IC/BPS phenotype. This article reviewed currently available literature and proposed a diagnosis and treatment algorithm. Based on bladder therapy combined with suitable physical and psychological therapies, a well-grounded multimodal therapy and treatment algorithm for IC/BPS following a diagnostic protocol are indispensable.

Efficacy and safety of hyperbaric oxygen therapy for fibromyalgia: a systematic review and meta-analysis

OBJECTIVE

To investigate the efficacy and safety of hyperbaric oxygen therapy (HBOT) for fibromyalgia (FM).

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

PubMed, EMBASE, Cochrane Library, Web of Science, VIP (China Science and Technology Journal Database), CNKI (China National Knowledge Infrastructure) and WanFang database were searched from from inception to 22 October 2022.

ELIGIBILITY CRITERIA

We included clinical trials (randomised controlled and non-randomised controlled trials) of HBOT for FM.

DATA EXTRACTION AND SYNTHESIS

Two researchers independently screened the literature, extracted data and evaluated the quality of the included studies, with disagreements resolved by a third researcher. The Cochrane Collaboration checklists and the Methodological Index for Non-randomised Studies were used to assess the risk of bias. Meta-analysis was performed by RevMan V.5.4.1 software. Random effect models were used for meta-analysis.

RESULTS

Nine studies were included in this review, with a total of 288 patients. For pain assessment, we combined the results of the Visual Analogue Scale and Widespread Pain Index. The results showed that HBOT could relieve the pain of FM patients compared with the control intervention (standardised mean difference=-1.56, 95% CI (-2.18 to -0.93), p<0.001, I 2=51%). Most included studies reported that HBOT ameliorated tender points, fatigue, multidimensional function, patient global and sleep disturbance in FM. Adverse events occurred in 44 of 185 patients (23.8%). Twelve patients (6.5%) withdrew because of adverse reactions. No serious adverse events or complications were observed.

CONCLUSIONS

HBOT might have a positive effect in improving pain, tender points, fatigue, multidimensional function, patient global and sleep disturbance in FM, with reversible side effects. Low pressure (less than 2.0 atmospheric absolute) may be beneficial to reduce adverse events in FM. Further studies should be carried out to evaluate the optimal protocol of HBOT in FM.

PROSPERO REGISTRATION NUMBER

CRD42021282920.

Evaluation of a Hyperbaric Oxygen Therapy Intervention in Individuals with Fibromyalgia

OBJECTIVE

To evaluate the feasibility and safety of hyperbaric oxygen therapy (HBOT) in patients with fibromyalgia (FM).

DESIGN

A cohort study with a delayed treatment arm used as a comparator.

SETTING

Hyperbaric Medicine Unit, Toronto General Hospital, Ontario, Canada.

SUBJECTS

Eighteen patients diagnosed with FM according to the American College of Rheumatology and a score ≥60 on the Revised Fibromyalgia Impact Questionnaire.

METHODS

Participants were randomized to receive immediate HBOT intervention (n = 9) or HBOT after a 12-week waiting period (n = 9). HBOT was delivered at 100% oxygen at 2.0 atmospheres per session, 5 days per week, for 8 weeks. Safety was evaluated by the frequency and severity of adverse effects reported by patients. Feasibility was assessed by recruitment, retention, and HBOT compliance rates. Both groups were assessed at baseline, after HBOT intervention, and at 3 months' follow-up. Validated assessment tools were used to evaluate pain, psychological variables, fatigue, and sleep quality.

RESULTS

A total of 17 patients completed the study. One patient withdrew after randomization. HBOT-related adverse events included mild middle-ear barotrauma in three patients and new-onset myopia in four patients. The efficacy of HBOT was evident in most of the outcomes in both groups. This improvement was sustained at 3-month follow-up assessment.

CONCLUSION

HBOT appears to be feasible and safe for individuals with FM. It is also associated with improved global functioning, reduced symptoms of anxiety and depression, and improved quality of sleep that was sustained at 3-month follow-up assessment.