Recruitment characteristics and non-adherence associated factors of fibromyalgia patients in a randomized clinical trial: A retrospective survival analysis

Efficacy of Immersive Virtual Reality Combined With Multisensor Biofeedback on Chronic Pain in Fibromyalgia: A Pilot Randomized Controlled Trial

OBJECTIVE

Fibromyalgia (FM) is a syndrome marked by chronic pain, fatigue, and mood disorders. Nonpharmacologic strategies are recommended to avoid overuse of opioids or nonsteroidal anti-inflammatory drugs, but current approaches often provide limited relief. This study aimed to preliminarily assess the efficacy and feasibility of a new combined intervention of immersive virtual reality with multisensor biofeedback (IVR-BF) in FM management.

METHODS

In this single-center, pilot, open-label, randomized controlled trial, adult patients with FM were randomly assigned 1:1 to either the treatment (TR) group, receiving IVR-BF immediately, or a waitlist control (WL) group, receiving IVR-BF after the TR group completed treatment. The primary outcome was reduction in visual analog scale (VAS) pain scores in the TR group, after five IVR-BF sessions, compared to the WL group, after the waiting period. Secondary outcomes included improvements in FM impact (FM Impact Questionnaire [FIQ] score) and qualitative aspect of pain (Short-form McGill Pain Questionnaire [SF-MPQ] score). A longitudinal analysis was conducted across all patients to examine the trends in VAS pain, SF-MPQ, and FIQ score during the trial.

RESULTS

Fifty patients were screened, and 20 female patients (10 TR and 10 WL) completed the trial and were analyzed. Those in the TR group showed significantly lower VAS pain scores compared to those in the WL group (P = 0.011), along with significant improvement in the FIQ score (P = 0.018). The longitudinal analysis revealed progressive improvements in VAS pain, SF-MPQ, and FIQ score, supported by physiologic improvements (heart rate variability, respiratory rate, skin conductance). No significant safety concerns were reported. Patients expressed a high level of satisfaction with the IVR experience.

CONCLUSION

IVR-BF is a feasible treatment that shows potential in reducing pain and improving quality of life in patients with FM, supporting the need for larger trials to further evaluate its efficacy.

High Body Mass Index Disrupts the Homeostatic Effects of Pain Inhibitory Control in the Symptomatology of Patients With Fibromyalgia

This study examines the influence of body mass index (BMI) on the relationship between quantitative sensory testing measures and clinical characteristics in fibromyalgia syndrome (FMS). Utilizing BMI as a categorical covariate (≥25 or ≥30 kg/m²) in associations between quantitative sensory testing metrics (pain-60, conditioned pain modulation, and temporal summation of pain [TSP]) and FMS clinical features, we explored BMI's role as both a confounder (change-in-estimate criterion-change equal or higher than 10%) and effect modifier (interaction term). Significant interactions revealed overweight/obese BMI as a modifier in the relationship between conditioned pain modification and both depression and symptom impact, with a homeostatic relationship between better clinical profile and pain inhibitory response observed solely in the normal-weight group. Similar results were found for pain-60 and depression. Additionally, BMI ≥30 kg/m² modified TSP's effect on pain, demonstrating lower pain with increased TSP, exclusively in the nonobese group. This study highlights the significant role of BMI in moderating the relationships of important pain inhibitory control processes and pain intensity, depression, and the overall impact of FMS symptoms. Our results suggest that high BMI states disrupt the homeostatic effects of pain inhibition, reducing its salutogenic response in FMS participants. We discuss the mechanistic and therapeutic implications of targeting BMI in FMS clinical trials and the potential impact of this important relationship. PERSPECTIVE: This investigation highlights the disruptive influence of high BMI on pain inhibitory control in fibromyalgia, unbalancing clinical symptoms such as pain and depression. It underscores the necessity of integrating BMI considerations into therapeutic approaches to enhance pain management and patient outcomes.

The effectiveness of stretching exercises in patients with fibromyalgia: A systematic review

Fibromyalgia is one of the most prevalent chronic pain disorders. Fibromyalgia is characterised by generalised pain. In addition, patients with fibromyalgia often have co-morbidity. Since no cure is available, the treatment is based on symptom management, with physical exercise being the recommended first-line treatment. Different exercise modalities have been examined, including the practice of stretching exercises. The aim of the systematic review is to summarise the efficacy of stretching exercises on fibromyalgia symptoms and to study the content and the quality of the current evidence. The review followed the recommendations of the PRISMA statement. The search for articles was performed in April 2023. We searched on MEDLINE, PubMed, CINAHL, Web of Science, SCOPUS, AMED, PEDro, ClinicalTrials.gov and the Cochrane Collaboration Trials Register. The search was updated in March 2024. The protocol was registered in PROSPERO. Risk of Bias was assessed using the Cochrane Risk of Bias tool, and quality assessment was performed using the GRADE approach. In total, 2586 studies were found in the database searches, of which nine were included in the analysis. The primary outcome was pain. Secondary outcomes were self-reported quality of life, fatigue and physical and mental functioning. The available evidence shows that stretching exercises may improve pain, health-related quality of life and physical and mental functioning, but the level of evidence is low. The main limitation is due to issues with the heterogeneity of the interventions and small sample sizes. Trial registration: PROSPERO registration number CRD42023399614. Key Points • Stretching exercises show promise in the treatment of fibromyalgia. They may improve pain, health-related quality of life, physical functioning and mental health, but the level of evidence is low. • This study goes beyond previous research by presenting a more comprehensive and detailed analysis of the content and methodological quality of the current evidence. • Further research with clearly outlined protocols must be carried out to advance our understanding of the benefits of stretching exercises on fibromyalgia symptoms.

Home-based, Remotely Supervised, 6-Week tDCS in Patients With Both MCI and Depression: A Randomized Double-Blind Placebo-Controlled Trial

As depressive symptom is considered a prodrome, a risk factor for progression from mild cognitive impairment (MCI) to dementia, improving depressive symptoms should be considered a clinical priority in patients with MCI undergoing transcranial direct current stimulation (tDCS) intervention. We aimed to comprehensively evaluate the efficacy of the home-based and remotely monitored tDCS in patients with both MCI and depression, by integrating cognitive, psychological, and electrophysiological indicators. In a 6-week, randomized, double blind, and sham-controlled study, 37 community-dwelling patients were randomly assigned to either an active or a sham stimulation group, and received 30 home-based sessions of 2 mA tDCS for 30 min with the anode located over the left and cathode over the right dorsolateral prefrontal cortex. We measured depressive symptoms, neurocognitive function, and resting-state electroencephalography. In terms of effects of both depressive symptoms and cognitive functions, active tDCS was not significantly different from sham tDCS. However, compared to sham stimulation, active tDCS decreased and increased the activation of delta and beta frequencies, respectively. Moreover, the increase in beta activity was correlated with the cognitive enhancement only in the active group. It was not possible to reach a definitive conclusion regarding the efficacy of tDCS on depression and cognition in patients with both MCI and depression. Nevertheless, the relationship between the changes of electrophysiology and cognitive performance suggests potential neuroplasticity enhancement implicated in cognitive processes by tDCS.

Assessing Ethnic Minority Representation in Fibromyalgia Clinical Trials: A Systematic Review of Recruitment Demographics

The under-representation of non-White participants in Western countries in clinical research has received increased attention, due to recognized physiological differences between ethnic groups, which may affect the efficacy and optimal dosage of some treatments. This review assessed ethnic diversity in pharmaceutical trials for fibromyalgia, a poorly understood chronic pain disorder. We also investigated longitudinal change to non-White participant proportions in trials and non-White participants' likelihood to discontinue with fibromyalgia research between trial stages (retention). First, we identified relevant trials conducted in the United States and Canada between 2000 and 2022, by searching PubMed, Web of Science, Scopus, and the Cochrane Library databases. In trials conducted both across the United States and Canada, and exclusively within the United States, approximately 90% of participants were White. A longitudinal analysis also found no change in the proportion of non-White participants in trials conducted across the United States and Canada between 2000 and 2022. Finally, we found no significant differences in trial retention between White and non-White participants. This review highlights the low numbers of ethnic minorities in fibromyalgia trials conducted in the United States and Canada, with no change to these proportions over the past 22 years. Furthermore, non-White participants were not more likely to discontinue with the fibromyalgia research once they were recruited.

The Analgesic Effect of Transcranial Direct Current Stimulation in Fibromyalgia: A Systematic Review, Meta-Analysis, and Meta-Regression of Potential Influencers of Clinical Effect

BACKGROUND

There is tentative evidence to support the analgesic effect of transcranial direct current stimulation (tDCS) in fibromyalgia (FM), with large variability in the effect size (ES) encountered in different clinical trials. Understanding the source of the variability and exploring how it relates to the clinical results could characterize effective neuromodulation protocols and ultimately guide care in FM pain. The primary objective of this study was to determine the effect of tDCS in FM pain as compared with sham tDCS. The secondary objective was to explore the relationship of methodology, population, and intervention factors and the analgesic effect of tDCS in FM.

MATERIALS AND METHODS

For the primary objective, a systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Randomized clinical trials (RCTs) investigating tDCS as an intervention for FM pain were searched in MEDLINE, Embase, and the Web Of Science. Studies were excluded if they used cross-over designs or if they did not use tDCS as an intervention for pain or did not measure clinical pain. Analysis for the main outcome was performed using a random-effects model. Risk of bias and evidence certainty were assessed for all studies using Cochrane Risk of Bias and Grading of Recommendations Assessment, Development, and Evaluation tools. For the secondary objective, a meta-regression was conducted to explore methodology, population, and intervention factors potentially related to the ES.

RESULTS

Sixteen RCTs were included. Six studies presented a high risk of bias. Significant reduction in pain scores were found for FM (standardized mean difference = 1.22, 95% CI = 0.80-1.65, p < 0.001). Subgroup analysis considering tDCS as a neural target revealed no differences between common neural sites. Meta-regression revealed that the duration of the tDCS protocol in weeks was the only factor associated with the ES, in which protocols that lasted four weeks or longer reported larger ES than shorter protocols.

CONCLUSIONS

Results suggest an analgesic effect of tDCS in FM. tDCS protocols that last four weeks or more may be associated with larger ESs. Definite conclusions are inadequate given the large heterogeneity and limited quality of evidence of the included studies.

Effects of Hypnotic Analgesia and Transcranial Direct Current Stimulation on Pain Tolerance and Corticospinal Excitability in Individuals with Fibromyalgia: A Cross-Over Randomized Clinical Trial

Objective

We compare the effect of HAS, a-tDCS on the left dorsolateral prefrontal cortex (l-DLPFC), and rest-testing on pain measures [(cold pressor test (CPT) (primary outcome) and heat pain threshold]. We also compare their effects on the motor evoked potential (MEP) (primary outcome), short intracortical inhibition (SICI), intracortical facilitation (ICF), and cortical silent period (CSP).

Methods

This randomized, blind, crossover trial included 18 women with fibromyalgia, aged from 18 to 65 years old. They received at random and in a crossover order a-tDCS over the l-DLPFC (2mA), HAS, or a rest-testing.

Results

HAS compared to a-tDCS increased the pain tolerance with a moderate effect size (ES) [Cohen's f=-0.78; (CI 95%; -1.48 to -0.12)]. While compared to rest-testing, HAS increased the CPT with a large ES [Cohen's f=-0.87; (CI 95%; -1.84 to -0.09)]. The a-tDCS compared to HAS increased the MEP amplitude with large ES [Cohen's f=-1.73 (CI 95%; -2.17 to -0.17)]. Likewise, its ES compared to rest-testing in the MEP size was large [Cohen's f=-1.03; (CI 95%; -2.06 to -0.08)].

Conclusion

These findings revealed that HAS affects contra-regulating mechanisms involved in perception and pain tolerance, while the a-tDCS increased the excitability of the corticospinal pathways. They give a subsidy to investigate their effect as approaches to counter regulate the maladaptive neuroplasticity involved in fibromyalgia.

Clinical Trial Registration

www.ClinicalTrials.gov, identifier - NCT05066568.