The scope and nature of pain in persons with multiple sclerosis

Physical Activity Moderates the Association Between Pain and Depressive Symptoms Among Persons with Multiple Sclerosis

OBJECTIVE

The present study examined physical activity as a possible moderator in the relationship between pain and depressive symptoms among persons with multiple sclerosis (PwMS).

METHOD

Fifty-three PwMS completed a comprehensive neuropsychological test battery and psychosocial questionnaires. Pain was operationalized as a composite of measures from the Brief Pain Inventory. Metabolic equivalents (METs) of energy expended during self-reported vigorous activity (VA), moderate activity (MA), and walking, as well as global physical activity which combined the three, were derived from the International Physical Activity Questionnaire-Short Form. Self-reported physical activity was measured using the Cognitive Health Questionnaire Exercise Scale. Regressions on depressive symptoms (Beck Depression Inventory-Fast Screen) examining both conceptualizations of physical activity, pain, and their interactions were explored.

RESULTS

Regression analyses revealed that interactions between pain and each measure of global physical activity were significant (p = .01). Simple effects tests revealed that pain only influenced depressive symptoms in PwMS with low global physical activity METs (p < .001) and low overall self-reported physical activity (p < .001). The separate interactions between pain and METs during self-reported VA, MA, and walking on depressive symptoms were not significant.

CONCLUSION

We found that global physical activity moderated the relationship between pain and depressive symptoms in MS. Specifically, pain influenced depressive symptoms in PwMS who engaged in less overall physical activity. These results highlight the importance of screening PwMS for pain and suggest that behavioral interventions aimed at increasing overall lifestyle physical activity may be useful in improving depressive outcomes in PwMS with pain.

Emotional burden among MS patients: associations between specific chronic pain diagnoses and psychological features

Central neuropathic pain (CNP) and musculoskeletal pain (MSP) are often comorbid with multiple sclerosis (MS), yet data on the emotional burden entailed by this comorbidity are very limited. We studied whether MS patients with CNP exhibited greater emotional burden and pain severity than those with MSP and whether this emotional burden was attributed to the MS, the chronic pain, or both. Participants were 125 MS patients (55 with CNP; 30 with MSP; 40 MS pain-free) and 30 healthy controls (HCs). Participants completed questionnaires assessing pain interference, pain catastrophizing, depression, anxiety, stress, hypervigilance, and chronic pain. Group comparisons and a two-step cluster analysis were performed, and the association between cluster membership and clinical group membership was evaluated. Chronic pain was stronger and more widespread in the CNP group than in the MSP group. Both pain groups had higher pain interference, pain catastrophizing, and stress compared to MS pain-free and HC groups. All MS groups had greater depression levels compared to HCs, and the CNP group had the highest anxiety level. The "high psychological distress" cluster comprised mainly participants with CNP (57%), and the "minimal psychological distress" cluster comprised mainly the MS pain-free and HC groups. In conclusion, CNP seems to induce greater emotional burden and pain severity than does MSP. Whereas depression may be attributed to MS, and anxiety to CNP, enhanced pain interference, catastrophizing, and stress may be attributed to the comorbidity of MS and chronic pain. Identifying these traits among MS patients and targeting them in management programs may contribute to more effective, individually based care.

Investigating the effectiveness of cognitive behavioral group therapy on psycho-social and emotional adaptability and cognitive flexibility in people with multiple sclerosis in Hamedan, Iran

INTRODUCTION

Multiple sclerosis is a chronic disease that profoundly impacts the patient's life. This study investigates the effectiveness of cognitive behavioral group therapy on psycho-social and emotional adaptability and cognitive flexibility in patients with multiple sclerosis in Hamedan city.

METHODS

The current study was semi-experimental and was designed with a pretest-posttest and follow-up with a control group. The statistical population included all people suffering from MS who referred to the MS association in Hamedan, Iran, in 2022, among whom 30 people were selected by sampling and randomly assigned to two experimental and control groups (each group of 15 people). The experimental group received cognitive behavioral intervention during eight sessions of 90 min weekly. The control group did not receive any interventions. The subjects were re-evaluated after 2 months for follow-up. The data were collected using a psycho-social adaptability with illness scale questionnaire, Bell's emotional adjustment questionnaire, and cognitive flexibility inventory questionnaire. The data were analyzed using variance analysis with repeated measurements using SPSS-21 software.

RESULTS

The results revealed that the cognitive behavioral therapy intervention significantly impacted the improvement of psycho-social and emotional adaptability and cognitive flexibility compared to the control group. This impact persisted until the follow-up stage.

CONCLUSION

Cognitive behavioral therapy removes cognitive barriers related to attitude and self-management by increasing the information, which improves psycho-social and emotional adaptability, cognitive flexibility, and, consequently, self-care behaviors.

Risk Factors for Chronic Prescription Opioid Use in Multiple Sclerosis

OBJECTIVE

To characterize patterns of prescription opioid use among individuals with multiple sclerosis (MS) and identify risk factors associated with chronic use.

DESIGN

Retrospective longitudinal cohort study examining US Department of Veterans Affairs electronic medical record data of Veterans with MS. The annual prevalence of prescription opioid use by type (any, acute, chronic, incident chronic) was calculated for each study year (2015-2017). Multivariable logistic regression was used to identify demographics and medical, mental health, and substance use comorbidities in 2015-2016 associated with chronic prescription opioid use in 2017.

SETTING

US Department of Veterans Affairs, Veteran's Health Administration.

PARTICIPANTS

National sample of Veterans with MS (N=14,974).

MAIN OUTCOME MEASURE

Chronic prescription opioid use (≥90 days).

RESULTS

All types of prescription opioid use declined across the 3 study years (chronic opioid use prevalence=14.6%, 14.0%, and 12.2%, respectively). In multivariable logistic regression, prior chronic opioid use, history of pain condition, paraplegia or hemiplegia, post-traumatic stress disorder, and rural residence were associated with greater risk of chronic prescription opioid use. History of dementia and psychotic disorder were both associated with lower risk of chronic prescription opioid use.

CONCLUSION

Despite reductions over time, chronic prescription opioid use remains common among a substantial minority of Veterans with MS and is associated with multiple biopsychosocial factors that are important for understanding risk for long-term use.

Identify the report as a systematic review

Background: To examine the relationship of vitamin B12 and folate concentrations to cognitive function, fatigue measures, physical function, quality of life (patient-centred outcomes) and homocysteine plasma concentrations (intermediate marker of cobalamin and folate deficiency) for patients with Multiple Sclerosis (MS). Methods: Systematic searches for eligible articles of MEDLINE, CINAHL, EMBASE, Scopus, Web of Science and OpenGray databases were conducted from 1983 in March 2021. Heterogeneity, Weighted Mean Difference (WMD) and Confidence Intervals (CI) calculated using Random Effects Model. Results: Sixteen studies were included involving; 616 MS patients and 655 healthy controls. 14 of these had acceptable or better quality but there was high heterogeneity. No difference was found between MS, healthy controls for folate and cobalamin concentrations; WMD 0.00ug/L (95% CI: -0.01, 0.01) and WMD 7.01pmol/L (95% CI: -25.54, 39.55) respectively. MS group showed mild-to-moderate disability WMD was 2.78 (95% CI: 2.00, 3.56). MS may be associated with elevated plasma homocysteine concentrations on average 2.47µmol/L more than healthy controls. Discussion: Physical ability of MS group was worse than healthy controls, but there was no difference in folate and cobalamin concentrations. This suggests folate and cobalamin are not influential factors in worsening physical function. There may be an association between worse cognitive function, and increased homocysteine concentrations. Results were inconclusive due to high heterogeneity and limited number of studies. A core outcome set would enable easier synthesis of future results.

Pain Prevalence in Multiple Sclerosis in a Lisbon Tertiary Hospital: A Cross-Sectional Study

Background: Multiple sclerosis is a chronic neurological disease with increasing incidence and prevalence worldwide being the main cause of non-traumatic disability in young adults. Both acute and chronic pain have been mentioned as the most common symptoms among those patients.

Objective: This study was designed to evaluate the pain experience among patients with multiple sclerosis by describing its prevalence, characteristics, analgesic treatment and its efficacy, and also the impact of pain on quality of life.

Methods: A cross-sectional observation survey was carried out on patients with multiple sclerosis followed in a tertiary hospital. Data were collected between December 2019 and March 2021 from a structured telephone inquiry, applying two questionnaires, the Brief Pain Inventory and the McGill Pain Questionnaire (MPQ), to evaluate the prevalence of pain and its impact on quality of life (QoL). Clinical records were also consulted to obtain data on disease duration, year of diagnosis, MS type, Expanded Disability Status Scale (EDSS) score.

Results: Our sample included 305 patients in a universe of 1500, mainly women, with mean age of 44.27 years, and most of them presented with an outbreak-remission subtype of disease. One hundred twenty-four patients experienced pain which corresponds to 41% of the patients. Considering the patients who experienced pain, 67.7% were under treatment and of these, 64.3% with only one painkiller. Pain significantly interfered with general activity, mood, and regular work.

Conclusion: Pain was an important symptom in this group of patients with MS and significantly interfered with mood, general activity, and regular work. The maximum intensity of pain felt by patients was significant and only 67.7% of patients were under analgesic treatment with mean pain relief of 54. NSAIDs were the most used drugs followed by gabapentinoids and acetaminophen for the management of pain. Medical community must continue to study this population in order to improve the approach to pain in these patients and improve quality of life.

Crotalphine Attenuates Pain and Neuroinflammation Induced by Experimental Autoimmune Encephalomyelitis in Mice

Multiple sclerosis (MS) is a demyelinating disease of inflammatory and autoimmune origin, which induces sensory and progressive motor impairments, including pain. Cells of the immune system actively participate in the pathogenesis and progression of MS by inducing neuroinflammation, tissue damage, and demyelination. Crotalphine (CRO), a structural analogue to a peptide firstly identified in Crotalus durissus terrificus snake venom, induces analgesia by endogenous opioid release and type 2 cannabinoid receptor (CB2) activation. Since CB2 activation downregulates neuroinflammation and ameliorates symptoms in mice models of MS, it was presently investigated whether CRO has a beneficial effect in the experimental autoimmune encephalomyelitis (EAE). CRO was administered on the 5th day after immunization, in a single dose, or five doses starting at the peak of disease. CRO partially reverted EAE-induced mechanical hyperalgesia and decreased the severity of the clinical signs. In addition, CRO decreases the inflammatory infiltrate and glial cells activation followed by TNF-α and IL-17 downregulation in the spinal cord. Peripherally, CRO recovers the EAE-induced impairment in myelin thickness in the sciatic nerve. Therefore, CRO interferes with central and peripheral neuroinflammation, opening perspectives to MS control.

Prevalence, co-occurrence, and trajectories of pain, fatigue, depression, and anxiety in the year following multiple sclerosis diagnosis

BACKGROUND

Pain, fatigue, depression, and anxiety are common in multiple sclerosis, but little is known about the presence, co-occurrence, and trajectories of these symptoms in the year after multiple sclerosis (MS) diagnosis.

OBJECTIVES

To determine, during the postdiagnosis year: (1) rates of pain, fatigue, depression, and anxiety; (2) rates of symptom co-occurrence; and (3) stability/change in symptom severity.

METHODS

Newly diagnosed adults with MS/clinically isolated syndrome (N = 230) completed self-report measures of pain, fatigue, depression, and anxiety at 1, 2, 3, 6, 9, and 12 months after MS diagnosis. Clinical significance was defined based on standardized cutoffs. Descriptive statistics and Sankey diagrams characterized rates and trajectories.

RESULTS

Participants endorsed clinically significant symptoms at some point in the postdiagnosis year at rates of 50.9% for pain, 62.6% for fatigue, 47.4% for depression, and 38.7% for anxiety. A majority of patients exhibited co-occurring symptoms-21.3% with two, 19.1% with three, and 17.4% with four. The proportions of patients with clinically significant symptoms were generally stable over time; however, rates of symptom development/recovery revealed fluctuations at the individual level.

CONCLUSIONS

Pain, fatigue, depression, and anxiety are prevalent in newly diagnosed MS. Prompt screening and evidence-based interventions are necessary if quality of life is to be optimized.

Pain Intensity and Pain Interference in People With Progressive Multiple Sclerosis Compared With People With Relapsing-Remitting Multiple Sclerosis

OBJECTIVE

To describe pain intensity and interference in people with progressive multiple sclerosis (MS), compare these with people with relapsing-remitting multiple sclerosis (RRMS), and identify common and unique factors associated with pain intensity in people with progressive MS and RRMS.

DESIGN

Observational, cross-sectional analysis using baseline data from a longitudinal survey on quality of life in participants with MS.

SETTING

Community.

PARTICIPANTS

A total of 573 adults with MS (N=573; progressive MS, n=142; RRMS, n=431).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Average pain intensity was measured by an 11-point numeric rating scale, and pain interference was measured by the Patient-Reported Outcomes Measurement Information System Pain Interference Short Form.

RESULTS

Participants with progressive MS reported moderate average pain intensity (3.22±2.50) and elevated pain interference (T score of 55.55±9.13). They did not differ significantly from those with RRMS in average pain intensity or pain interference. Common factors associated with higher average pain intensity were more severe disability, lower education level, unemployment, and current smoking. In those with progressive MS, older age was associated with lower average pain intensity.

CONCLUSIONS

Pain intensity and interference are similar across MS types. In addition to assessing and treating pain, it is important to screen for modifiable pain-related factors, such as smoking cessation, in this population.

Characterizing chronic pain phenotypes in multiple sclerosis: a nationwide survey study

ABSTRACT

Chronic pain is highly prevalent in multiple sclerosis (MS). Pain heterogeneity may contribute to poor treatment outcomes. The aim of this study was to characterize pain phenotypes distributions in persons with MS and compare pain phenotypes in terms of pain intensity, frequency of chronic overlapping pain conditions, and use and analgesic effects of different classes of pain medications. Data were collected through a national web-based survey with measures of neuropathic (painDETECT) and nociplastic pain (Fibromyalgia Survey Criteria), chronic overlapping pain conditions, and pain medication use and pain relief. In a sample of N = 842 adults with chronic pain and MS, the largest proportion (41%) showed evidence of nociceptive pain, 27% had mixed neuropathic/nociplastic pain, 23% had nociplastic pain, and 9% had neuropathic pain. Nociplastic pain was associated with significantly higher pain intensity and frequency of chronic overlapping pain conditions. Across all pain types, high frequency of pain medication use along with poor-modest pain relief was reported. Cannabis use for pain was more common, and pain relief ratings were higher among those with nociplastic pain, relative to nociceptive pain. Although NSAID use was highest among those with nociplastic pain (80%), pain relief ratings for NSAIDs were highest among those with nociceptive pain. These findings underscore the need for multidimensional assessment of pain in MS with greater emphasis on the identification of pain phenotype. An improved characterization of pain as a multifaceted condition in MS could inform therapeutic approaches.

Longitudinal prevalence and determinants of pain in multiple sclerosis: results from the German National Multiple Sclerosis Cohort study

Pain is frequent in multiple sclerosis (MS) and includes different types, with neuropathic pain (NP) being most closely related to MS pathology. However, prevalence estimates vary largely, and causal relationships between pain and biopsychosocial factors in MS are largely unknown. Longitudinal studies might help to clarify the prevalence and determinants of pain in MS. To this end, we analyzed data from 410 patients with newly diagnosed clinically isolated syndrome or relapsing-remitting MS participating in the prospective multicenter German National MS Cohort Study (NationMS) at baseline and after 4 years. Pain was assessed by self-report using the PainDETECT Questionnaire. Neuropsychiatric assessment included tests for fatigue, depression, and cognition. In addition, sociodemographic and clinical data were obtained. Prevalence of pain of any type was 40% and 36% at baseline and after 4 years, respectively, whereas prevalence of NP was 2% and 5%. Pain of any type and NP were both strongly linked to fatigue, depression, and disability. This link was even stronger after 4 years than at baseline. Moreover, changes in pain, depression, and fatigue were highly correlated without any of these symptoms preceding the others. Taken together, pain of any type seems to be much more frequent than NP in early nonprogressive MS. Moreover, the close relationship between pain, fatigue, and depression in MS should be considered for treatment decisions and future research on a possible common pathophysiology.

Sensory and pain modulation profiles of ongoing central neuropathic extremity pain in multiple sclerosis

BACKGROUND

Central neuropathic extremity pain (CNEP) is the most frequent type of pain in multiple sclerosis (MS). The aim of the present study was to evaluate sensory and pain modulation profiles in MS patients with CNEP.

METHODS

In a single-centre observational study, a group of 56 CNEP MS patients was compared with 63 pain-free MS patients and with a sex- and age-adjusted control group. Standardized quantitative sensory testing (QST) and dynamic QST (dQST) protocols comprising temporal summation and conditioned pain modulation tests were used to compare sensory profiles.

RESULTS

Loss-type QST abnormalities in both thermal and mechanical QST modalities prevailed in both MS subgroups and correlated significantly with higher degree of disability expressed as Expanded Disability Status Scale (EDSS). Comparison of sensory phenotypes disclosed a higher frequency of the 'sensory loss' prototypic sensory phenotype in the CNEP subgroup (30%) compared with pain-free MS patients (6%; p = .003).

CONCLUSION

The role of aging process and higher lesion load in the spinothalamocortical pathway might be possible explanation for pain development in this particular 'deafferentation' subtype of central neuropathic pain in MS. We were unable to support the role of central sensitization or endogenous facilitatory and inhibitory mechanisms in the development of CNEP in MS.

SIGNIFICANCE

This article presents higher prevalence of the 'sensory loss' prototypic sensory phenotype in multiple sclerosis patients with central extremity neuropathic pain compared to pain-free patients. Higher degree of disability underlines the possible role of higher lesion load in the somatosensory pathways in this particular 'deafferentation' type of central neuropathic pain.

Clinical perspective on pain in multiple sclerosis

Pain is an important and frequent symptom in multiple sclerosis (MS), which leads to a low quality of life, increased disability level, and lack of employment and mental health. Recently, studies have shown increased interest in pain in MS and there is a growing evidence of its prevalence. However, the literature suffers from lack of experimental studies focusing on pain reduction. This topical review summarizes the current knowledge about pain in MS with its definitions, assessments, treatments and rehabilitation within a holistic perspective.

Daily Temporal Associations Between Physical Activity and Symptoms in Multiple Sclerosis

Background

Symptom severity is negatively associated with physical activity in multiple sclerosis (MS). However, it is unclear how physical activity and symptoms correlate on a day-to-day basis in persons with MS.

Purpose

To determine the temporal within-person associations of pain, fatigue, depressed mood, and perceived cognitive function with physical activity in MS.

Methods

Ambulatory adults with MS (N = 107) completed 7 days of home monitoring. Continuous physical activity data (assessed via wrist-worn accelerometer) and concurrent ecological momentary assessment (5X/day) of pain, fatigue, depressed mood, and perceived cognitive function were collected. Data were analyzed using multilevel mixed modeling.

Results

Fatigue and depressed mood demonstrated bidirectional associations with physical activity, whereas pain and cognitive function did not. Higher than usual fatigue (B = -5.83, p = .001) and depressed mood (B = -4.12, p = .03) were followed by decreased physical activity. In contrast, higher than usual physical activity was associated with subsequent decline in fatigue (B = -0.001, p = .02) and depressed mood (B = -0.0007, p = .02); however, the association between physical activity and fatigue varied across the day.

Conclusions

Physical activity is dynamically related to fatigue and mood on a moment-to-moment basis in MS. Efforts to increase physical activity in MS must incorporate a focus on how symptoms affect and are affected by activity.

Crotoxin down-modulates pro-inflammatory cells and alleviates pain on the MOG35-55-induced experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis

Multiple sclerosis (MS) is a Central Nervous System inflammatory demyelinating disease that has as primary symptoms losses of sensory and motor functions, including chronic pain. To date, however, few studies have investigated the mechanisms of chronic pain in animal models of MS since locomotor impairments render difficult its evaluation. It was previously demonstrated that in the MOG_35-55-induced EAE, an animal model of MS, the hypernociception appears before the onset of motor disability, allowing for the study of these two phenomena separately. Here, we evaluated the effect of crotoxin (CTX), a neurotoxin isolated from the Crotalus durissus terrificus snake venom that displays, at non-toxic dose, antinociceptive, anti-inflammatory and immunomodulatory effects, in the pain and in symptoms progression of EAE. The pain threshold of female C57BL/6 mice decreased at the 4th day after immunization, while the first sign of disease appeared around the 11st-12nd days, coinciding with the onset of motor abnormalities. CTX (40 µg/kg, s.c.) administered in a single dose on the 5th day after immunization, induced a long-lasting analgesic effect (5 days), without interfering with the clinical signs of the disease. On the other hand, when crotoxin was administered for 5 consecutive days, from 5th-9th day after immunization, it induced analgesia and also reduced EAE progression. The antinociceptive effect of crotoxin was blocked by Boc-2 (0.5 mg/kg, i.p.), a selective antagonist of formyl peptide receptors, by NDGA (30 μg/kg, i.p.), a lipoxygenase inhibitor and by atropine sulfate (10 mg/kg, i.p.), an antagonist of muscarinic receptors, administered 30 min before CTX. CTX was also effective in decreasing EAE clinical signs even when administered after its onset. Regarding the interactions between neurons and immunocompetent cells, CTX, in vitro, was able to reduce T cell proliferation, decreasing Th1 and Th17 and increasing Treg cell differentiation. Furthermore, in EAE model, the treatment with 5 consecutive doses of CTX inhibited IFN-γ-producing T cells, GM-CSF-producing T cells, reduced the frequency of activated microglia/macrophages within the CNS and decreased the number of migrating cell to spinal cord and cerebellum at the peak of the disease. These results suggest that CTX is a potential treatment not only for pain alteration but also for clinical progression induced by the disease as well as an useful tool for the development of new therapeutic approaches for the multiple sclerosis control.

Cognitive Behavioral Therapy for the Management of Multiple Sclerosis-Related Pain: A Randomized Clinical Trial

Background

Pain is a common and often debilitating symptom in persons with multiple sclerosis (MS). Besides interfering with daily functioning, pain in MS is associated with higher levels of depression and anxiety. Although cognitive behavioral therapy (CBT) for pain has been found to be an effective treatment in other populations, there has been a dearth of research in persons with MS.

Methods

Persons with MS with at least moderate pain severity (N = 20) were randomly assigned to one of two groups: CBT plus standard care or MS-related education plus standard care, each of which met for 12 sessions. Changes in pain severity, pain interference, and depressive symptom severity from baseline to 15-week follow-up were assessed using a 2×2 factorial design. Participants also rated their satisfaction with their treatment and accomplishment of personally meaningful behavioral goals.

Results

Both treatment groups rated their treatment satisfaction as very high and their behavioral goals as largely met, although only the CBT plus standard care group's mean goal accomplishment ratings represented significant improvement. Although there were no significant differences between groups after treatment on the three primary outcomes, there was an overall improvement over time for pain severity, pain interference, and depressive symptom severity.

Conclusions

Cognitive behavioral therapy or education-based programs may be helpful adjunctive treatments for persons with MS experiencing pain.

Evaluation of Neuropathic Extremity Pain in Patients with Multiple Sclerosis

Introduction:

Neuropathic extremity pain is one of the most common symptoms of multiple sclerosis (MS). This study was aimed to evaluate and compare the frequency and severity of neuropathic extremity pain in subtypes of MS.

Methods:

Patients with the diagnosis of MS were included in the study, consecutively. Patients’ demographic and clinical data were recorded. Patients’ pain severity was assessed with visual analog scale (VAS). For the evaluation of neuropathic pain Leeds assessment of neuropathic symptoms and signs (LANSS) and douleur neuropathique 4 questions (DN4) were used. Disability was assessed with the Extended Disability Status Scale (EDSS).

Results:

One hundred and three patients were included and 82.5% of them had relapsing-remitting (RR) MS. According to LANSS and DN4, 47.6% of patients had neuropathic pain. Female patients had significantly higher pain scores. There was no significant difference between the subtypes of MS based on having neuropathic pain. Patients with seconder progressive (SP) MS had significantly higher EDSS. A significant positive correlation was detected between EDSS score and duration of disease.

Conclusion:

Regardless of the MS subtype patients had neuropathic pain. Patients with SP had significantly higher disease duration and EDSS which were correlated with each other. All patients with the diagnosis of MS should be evaluated for neuropathic pain.

Neural stimulations regulate the infiltration of immune cells into the CNS

The systemic regulation of immune reactions by the nervous system is well studied and depends on the release of hormones. Some regional regulations of immune reactions, on the other hand, depend on specific neural pathways. Better understanding of these regulations will expand therapeutic applications for neuroimmune and organ-to-organ functional interactions. Here, we discuss one regional neuroimmune interaction, the gateway reflex, which converts specific neural inputs into local inflammatory outputs in the CNS. Neurotransmitters released by the inputs stimulate specific blood vessels to express chemokines, which serve as a gateway for immune cells to extravasate into the target organ such as the brain or spinal cord. Several types of gateway reflexes have been reported, and each controls distinct CNS blood vessels to form gateways that elicit local inflammation, particularly in the presence of autoreactive immune cells. For example, neural stimulation by gravity creates the initial entry point to the CNS by CNS-reactive pathogenic CD4+ T cells at the dorsal vessels of fifth lumbar spinal cord, while pain opens the gateway at the ventral side of blood vessels in the spinal cord. In addition, it was recently found that local inflammation by the gateway reflex in the brain triggers the activation of otherwise resting neural circuits to dysregulate organ functions in the periphery including the upper gastrointestinal tract and heart. Therefore, the gateway reflex represents a novel bidirectional neuroimmune interaction that regulates organ functions and could be a promising target for bioelectric medicine.

Gateway reflex: Local neuroimmune interactions that regulate blood vessels

Neuroimmunology is a research field that intersects neuroscience and immunology, with the larger aim of gaining significant insights into the pathophysiology of chronic inflammatory diseases such as multiple sclerosis. Conventional studies in this field have so far mainly dealt with immune responses in the nervous system (i.e. neuroinflammation) or systemic immune regulation by the release of glucocorticoids. On the other hand, recently accumulating evidence has indicated bidirectional interactions between specific neural activations and local immune responses. Here we discuss one such local neuroimmune interaction, the gateway reflex. The gateway reflex represents a mechanism that translates specific neural stimulations into local inflammatory outcomes by changing the state of specific blood vessels to allow immune cells to extravasate, thus forming the gateway. Several types of gateway reflex have been identified, and each regulates distinct blood vessels to create gateways for immune cells that induce local inflammation. The gateway reflex represents a novel therapeutic strategy for neuroinflammation and is potentially applicable to other inflammatory diseases in peripheral organs.

Effectiveness of Exercise Interventions for Pain Reduction in People With Multiple Sclerosis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

To systematically review the evidence of the effect of exercise compared with passive control on pain in people with multiple sclerosis.

DATA SOURCE AND STUDY SELECTION

Five electronic databases were searched for randomized controlled trials published up to March 2017 that recruited people with multiple sclerosis where exercise was the intervention and pain was an outcome (PROSPERO registration number CRD42017060489).

STATISTICAL ANALYSIS

A random-effects meta-analysis was conducted to estimate the standardized mean difference of the effect of exercise on pain between treatment and control groups. We assessed risk of bias, fitted meta-regression models to explore heterogeneity between studies, and assessed small study effects.

DATA SYNTHESIS

Ten studies met the inclusion criteria (total sample size=389), and all studies were at high risk of bias. We found that exercise interventions were associated with less pain compared with passive control groups (standardized mean difference=-.46; 95% CI, -.92 to .00). There was high between-study heterogeneity (I²=77.0%), which was not explained by the prespecified study characteristics. There was also some evidence of small study effects.

CONCLUSION

This is the first systematic review of the effect of exercise interventions on pain in people with multiple sclerosis, a chronic neurological disorder that affects 2.5 million people. We found some evidence that exercise compared with passive control alleviates pain in this population, but there were limitations in reporting and study quality with high risk of bias of individual studies and heterogeneity between studies.

USE OF NEUROFEEDBACK AND MINDFULNESS TO ENHANCE RESPONSE TO HYPNOSIS TREATMENT IN INDIVIDUALS WITH MULTIPLE SCLEROSIS: Results From a Pilot Randomized Clinical Trial

This pilot study evaluated the possibility that 2 interventions hypothesized to increase slower brain oscillations (e.g., theta) may enhance the efficacy of hypnosis treatment, given evidence that hypnotic responding is associated with slower brain oscillations. Thirty-two individuals with multiple sclerosis and chronic pain, fatigue, or both, were randomly assigned to 1 of 2 interventions thought to increase slow wave activity (mindfulness meditation or neurofeedback training) or no enhancing intervention, and then given 5 sessions of self-hypnosis training targeting their presenting symptoms. The findings supported the potential for both neurofeedback and mindfulness to enhance response to hypnosis treatment. Research using larger sample sizes to determine the generalizability of these findings is warranted.

Neurological, physical and sociodemographic correlates of employment in multiple sclerosis: A meta-analysis

Illness severity and sociodemographic characteristics of 7,053 employees with multiple sclerosis and 11,043 peers not in the workforce were compared (Hedges' g with 95% confidence interval and p values). Pooled findings from 25 studies confirmed the main role of a relapsing-remitting disease course and higher education to employment. To a lesser extent, disease duration, fatigue and pain symptoms and age also differentiated the two groups. Vocational interventions for persons with multiple sclerosis should focus on job retention, including mechanisms to accommodate and facilitate functional independence. Longitudinal data are needed to distinguish the characteristics of those who achieve and maintain competitive employment.

The Gateway Reflex, a Novel Neuro-Immune Interaction for the Regulation of Regional Vessels

The gateway reflex is a new phenomenon that explains how immune cells bypass the blood-brain barrier to infiltrate the central nervous system (CNS) and trigger neuroinflammation. To date, four examples of gateway reflexes have been discovered, each described by the stimulus that evokes the reflex. Gravity, electricity, pain, and stress have all been found to create gateways at specific regions of the CNS. The gateway reflex, the most recently discovered of the four, has also been shown to upset the homeostasis of organs in the periphery through its action on the CNS. These reflexes provide novel therapeutic targets for the control of local neuroinflammation and organ function. Each gateway reflex is activated by different neural activations and induces inflmammation at different regions in the CNS. Therefore, it is theoretically possible to manipulate each independently, providing a novel therapeutic strategy to control local neuroinflammation and peripheral organ homeostasis.

Improving the quality of depression and pain care in multiple sclerosis using collaborative care: The MS-care trial protocol

BACKGROUND AND OBJECTIVES

Evidence-based pharmacological and behavioral interventions are often underutilized or inaccessible to persons with multiple sclerosis (MS) who have chronic pain and/or depression. Collaborative care is an evidence-based patient-centered, integrated, system-level approach to improving the quality and outcomes of depression care. We describe the development of and randomized controlled trial testing a novel intervention, MS Care, which uses a collaborative care model to improve the care of depression and chronic pain in a MS specialty care setting.

METHODS

We describe a 16-week randomized controlled trial comparing the MS Care collaborative care intervention to usual care in an outpatient MS specialty center. Eligible participants with chronic pain of at least moderate intensity (≥3/10) and/or major depressive disorder are randomly assigned to MS Care or usual care. MS Care utilizes a care manager to implement and coordinate guideline-based medical and behavioral treatments with the patient, clinic providers, and pain/depression treatment experts. We will compare outcomes at post-treatment and 6-month follow up.

PROJECTED PATIENT OUTCOMES

We hypothesize that participants randomly assigned to MS Care will demonstrate significantly greater control of both pain and depression at post-treatment (primary endpoint) relative to those assigned to usual care. Secondary analyses will examine quality of care, patient satisfaction, adherence to MS care, and quality of life. Study findings will aid patients, clinicians, healthcare system leaders, and policy makers in making decisions about effective care for pain and depression in MS healthcare systems. (PCORI- IH-1304-6379; clinicaltrials.gov: NCT02137044). This trial is registered at ClinicalTrials.gov, protocol NCT02137044.

Brain micro-inflammation at specific vessels dysregulates organ-homeostasis via the activation of a new neural circuit

Impact of stress on diseases including gastrointestinal failure is well-known, but molecular mechanism is not understood. Here we show underlying molecular mechanism using EAE mice. Under stress conditions, EAE caused severe gastrointestinal failure with high-mortality. Mechanistically, autoreactive-pathogenic CD4+ T cells accumulated at specific vessels of boundary area of third-ventricle, thalamus, and dentate-gyrus to establish brain micro-inflammation via stress-gateway reflex. Importantly, induction of brain micro-inflammation at specific vessels by cytokine injection was sufficient to establish fatal gastrointestinal failure. Resulting micro-inflammation activated new neural pathway including neurons in paraventricular-nucleus, dorsomedial-nucleus-of-hypothalamus, and also vagal neurons to cause fatal gastrointestinal failure. Suppression of the brain micro-inflammation or blockage of these neural pathways inhibited the gastrointestinal failure. These results demonstrate direct link between brain micro-inflammation and fatal gastrointestinal disease via establishment of a new neural pathway under stress. They further suggest that brain micro-inflammation around specific vessels could be switch to activate new neural pathway(s) to regulate organ homeostasis.

DOI:http://dx.doi.org/10.7554/eLife.25517.001

Pain, Fatigue, and Cognitive Symptoms Are Temporally Associated Within but Not Across Days in Multiple Sclerosis

OBJECTIVE

To examine the temporal associations, within day and day to day, between pain, fatigue, depressed mood, and cognitive function in multiple sclerosis (MS).

DESIGN

Repeated-measures study involving 7 days of ecological momentary assessment (EMA) of symptoms 5 times a day; multilevel mixed models were used to analyze data.

SETTING

Community.

PARTICIPANTS

Ambulatory adults (N=107) with MS.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

EMA of pain, fatigue, depressed mood, and cognitive function rated on a 0 to 10 scale.

RESULTS

Fatigue and pain were linked within day such that higher pain was associated with higher subsequent fatigue (B=.09, P=.04); likewise, higher fatigue was associated with higher pain in the following time frame (B=.05, P=.04). Poorer perceived cognitive function preceded increased subsequent pain (B=.08, P=.007) and fatigue (B=.10, P=.01) within day. Depressed mood was not temporally linked with other symptoms. In terms of day-to-day effects, a day of higher fatigue related to decreased next day fatigue (B=-.16, P=.01), and a day of higher depressed mood related to increased depressed mood the next day (B=.17, P=.01). There were no cross-symptom associations from one day to the next.

CONCLUSIONS

Findings provide new insights on how common symptoms in MS relate to each other and vary within and over days. Pain and fatigue show evidence of a dynamic bidirectional relation over the course of a day, and worsening of perceived cognitive function preceded worsening of both pain and fatigue. Most temporal associations between symptoms occur within the course of a day, with relatively little carryover from one day to the next.

How Do Pain, Fatigue, Depressive, and Cognitive Symptoms Relate to Well-Being and Social and Physical Functioning in the Daily Lives of Individuals With Multiple Sclerosis?

OBJECTIVE

To examine the relative association between daily change in pain, fatigue, depressed mood, and cognitive function and 4 outcomes-positive affect and well-being, ability to participate in social roles and activities, upper extremity (UE) functioning, and lower extremity (LE) functioning.

DESIGN

Data analysis, multilevel mixed modeling.

SETTING

General community.

PARTICIPANTS

Ambulatory adults (N=102) with multiple sclerosis.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Customized short-forms of the Quality of Life in Neurological Disorders positive affect and well-being, UE functioning, and LE functioning item banks and the Patient-Reported Outcomes Measurement Information System ability to participate in social roles and activities item bank adapted for daily use and administered as end-of-day diaries.

RESULTS

Above and beyond the effects of demographic and clinical covariates, daily pain was associated with 3 of the 4 outcomes; days of higher than usual pain were related to lower same-day social participation (unstandardized β, B=-1.00; P=.002), UE functioning (B=-1.04; P=.01), and LE functioning (B=-.71; P=.04). Daily fatigue and depressed mood were independently related to daily positive affect and well-being; days of worse fatigue (B=-.54; P=.006) and depressed mood (B=-1.17; P<.0001) were related to lower same-day well-being.

CONCLUSIONS

The results indicate the role of fluctuations in symptoms in daily functioning and quality of life of individuals with multiple sclerosis. Daily increases in pain intensity are related to social and physical functioning, whereas increases in fatigue and depressed mood are related to lower daily well-being. Findings implicate a person-centered approach to monitoring and treating symptoms.

Ecological Momentary Assessment of Pain, Fatigue, Depressive, and Cognitive Symptoms Reveals Significant Daily Variability in Multiple Sclerosis

OBJECTIVE

To describe the daily variability and patterns of pain, fatigue, depressed mood, and cognitive function in persons with multiple sclerosis (MS).

DESIGN

Repeated-measures observational study of 7 consecutive days of home monitoring, including ecological momentary assessment (EMA) of symptoms. Multilevel mixed models were used to analyze data.

SETTING

General community.

PARTICIPANTS

Ambulatory adults (N=107) with MS recruited through the University of Michigan and surrounding community.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

EMA measures of pain, fatigue, depressed mood, and cognitive function rated on a 0 to 10 scale, collected 5 times a day for 7 days.

RESULTS

Cognitive function and depressed mood exhibited more stable within-person patterns than pain and fatigue, which varied considerably within person. All symptoms increased in intensity across the day (all P<.02), with fatigue showing the most substantial increase. Notably, this diurnal increase varied by sex and age; women showed a continuous increase from wake to bedtime, whereas fatigue plateaued after 7 pm for men (wake-bed B=1.04, P=.004). For the oldest subgroup, diurnal increases were concentrated to the middle of the day compared with younger subgroups, which showed an earlier onset of fatigue increase and sustained increases until bed time (wake-3 pm B=.04, P=.01; wake-7 pm B=.03, P=.02). Diurnal patterns of cognitive function varied by education; those with advanced college degrees showed a more stable pattern across the day, with significant differences compared with those with bachelor-level degrees in the evening (wake-7 pm B=-.47, P=.02; wake-bed B=-.45, P=.04).

CONCLUSIONS

Findings suggest that chronic symptoms in MS are not static, even over a short time frame; rather, symptoms-fatigue and pain in particular-vary dynamically across and within days. Incorporation of EMA methods should be considered in the assessment of these chronic MS symptoms to enhance assessment and treatment strategies.

Are intensive data collection methods in pain research feasible in those with physical disability? A study in persons with chronic pain and spinal cord injury

PURPOSE

Intensive repeated measures data collection procedures, such as ecological momentary assessment (EMA) and end-of-day (EOD) diaries, are becoming more prominent in pain research. Existing data on the feasibility of such methods is encouraging; however, almost nothing is known about feasibility in clinical populations with significant physical disabilities. Research methodology feasibility is crucial to the inclusion of individuals with physical disability in pain research given the high prevalence and impact of pain in these populations. The aim of this study was to examine study compliance, protocol acceptability, and reactivity of intensive data collection methods in adults with chronic pain and spinal cord injury (SCI).

METHODS

Secondary analysis of data from a 7-day EMA and EOD diary study in a sample of 131 community dwelling adults with SCI.

RESULTS

Results showed rates of missing data ranged from 18.4 to 22.8% across measures. Participant compliance was related to time of day/presence of audible prompts, mobility aid use, race, and baseline levels of pain and pain interference, with more missing data at wake and bedtimes/no prompts, and for those who used hand-held mobility devices, identified as black/African American, and/or reported higher baseline pain and pain interference. Participants rated the study methodology as generally highly acceptable and expressed willingness to participate in similar studies of much longer duration. There was no evidence of reactivity, defined as temporal shifts in pain or pain interference ratings.

CONCLUSIONS

Overall, intensive pain data collection is feasible in persons with SCI with no evidence that the methodology impacts pain intensity or pain interference ratings.

An Empirical Investigation of a Biopsychosocial Model of Pain in Multiple Sclerosis

OBJECTIVES

Pain is a significant problem for many individuals with multiple sclerosis (MS). Pain is often associated with other MS symptoms (eg, physical, sensorimotor, cognitive declines), and both pain and MS symptoms are hypothesized to contribute to psychosocial problems (eg, depression), other symptoms (eg, fatigue, sleep disturbance), and functional impairments (eg, pain interference). On the basis of a biopsychosocial model, we sought to: (1) examine the associations between pain, MS symptoms, depression, psychosocial, and functional variables and (2) identify possible risk and protective factors associated with pain in MS.

MATERIALS AND METHODS

A cross-sectional survey was completed by 424 individuals with MS. Pain, MS symptoms, demographics, MS diagnostic factors, and psychosocial and functional variables were assessed. Data were analyzed by structural equation models.

RESULTS

Participants were predominantly white (92%), middle-aged (mean=50.7 y), and female (80%). Results indicated that pain severity and depression accounted for >50% of the variance in pain interference. Although pain contributed minimally to fatigue and sleep quality, depression and MS symptoms predicted 49% of the variance in fatigue, and depression was largely responsible for the 40% of predicted variance in sleep quality. Identified risk factors for pain were low educational attainment and lack of a committed/marital relationship, even while controlling for diagnostic and other key demographic variables.

DISCUSSION

Results highlight the importance of targeting interventions toward improving coping skills and social support within the context of pain and MS. Research is needed to determine whether effectively targeting depression in MS results in improvements of other critical psychosocial and physical functioning domains.

Prevalence of neuropathic pain in early multiple sclerosis

Background:

Pain is considered a frequent symptom in multiple sclerosis. Neuropathic pain is the type of pain most closely related to the pathology of multiple sclerosis and its prevalence estimates vary largely.

Objective:

We prospectively assessed the prevalence of neuropathic pain in patients with early multiple sclerosis and investigated the association of neuropathic pain with other clinical parameters.

Methods:

A total of 377 outpatients with multiple sclerosis at an early disease stage were included in this prospective study. Mean disease duration was 4.2 years, mean Expanded Disability Status Scale (EDSS) score was 1.6, 96.8% of patients were classified as having relapsing–remitting multiple sclerosis. Neuropathic pain was assessed using the PainDETECT questionnaire (PDQ). Depression, fatigue and cognition were assessed using the Beck Depression Inventory (BDI), the Fatigue Scale for Motor and Cognitive Functions (FSMC) and the Paced Auditory Serial Addition Test.

Results:

PDQ scores indicative of neuropathic pain were found in 4.2% of patients. Regression analysis revealed EDSS, BDI and FMSC scores as strongest predictors of PDQ scores.

Conclusions:

Neuropathic pain appears to be less frequent in early multiple sclerosis than expected and is significantly associated with disability, depression and fatigue. The assessment and therapy of pain in multiple sclerosis should thus take into account neuropsychiatric symptoms already at early disease stages.

Cross-Sectional Examination of the Associations Between Symptoms, Community Integration, and Mental Health in Multiple Sclerosis

OBJECTIVE

To determine the frequency and severity of 8 symptoms in persons with multiple sclerosis (MS) and to examine the association between these symptoms and community integration and mental health.

DESIGN

Cross-sectional survey that assessed 8 symptoms (pain, fatigue, imbalance, numbness, weakness, shortness of breath, vision loss, and memory loss), disease progression (self-report version of the Expanded Disability Status Scale), community integration, and mental health.

SETTING

Community.

PARTICIPANTS

Adults with self-reported MS who responded to a mailed survey (N=180).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The presence and intensity of symptoms were measured with a symptoms checklist. Community integration was assessed with the Community Integration Questionnaire, and mental health was measured by the Mental Health Index of the Medical Outcomes Study 36-Item Short-Form Health Survey.

RESULTS

The average number of symptoms reported was 5.07±2.18. The most common symptoms (fatigue, weakness, and imbalance) were also rated as the most severe. Not all symptoms were associated with level of disease progression or with MS subtype. Symptoms related to mobility were more likely to be associated with these variables. The 8 symptoms as a whole accounted for significant amounts of variance (range, 13%-21%) in measures of community integration and mental health, with specific symptoms making differential independent contributions to these measures.

CONCLUSIONS

This study demonstrates that most individuals with MS report a number of bothersome symptoms. Type of MS or level of progression does not tell the whole story regarding the impact of symptoms.

Central Neuropathic Pain Syndromes

Chronic pain is common in patients with neurologic complications of a central nervous system insult such as stroke. The pain is most commonly musculoskeletal or related to obligatory overuse of neurologically unaffected limbs. However, neuropathic pain can result directly from the central nervous system injury. Impaired sensory discrimination can make it challenging to differentiate central neuropathic pain from other pain types or spasticity. Central neuropathic pain may also begin months to years after the injury, further obscuring recognition of its association with a past neurologic injury. This review focuses on unique clinical features that help distinguish central neuropathic pain. The most common clinical central pain syndromes-central poststroke pain, multiple sclerosis-related pain, and spinal cord injury-related pain-are reviewed in detail. Recent progress in understanding of the pathogenesis of central neuropathic pain is reviewed, and pharmacological, surgical, and neuromodulatory treatments of this notoriously difficult to treat pain syndrome are discussed.

Use of Neurofeedback to Enhance Response to Hypnotic Analgesia in Individuals With Multiple Sclerosis

This proof of principle study examined the potential benefits of EEG neurofeedback for increasing responsiveness to self-hypnosis training for chronic pain management. The study comprised 20 individuals with multiple sclerosis (MS) who received 5 sessions of self-hypnosis training--1 face-to-face session and 4 prerecorded sessions. Participants were randomly assigned to have the prerecorded sessions preceded by either (a) EEG biofeedback (neurofeedback) training to increase left anterior theta power (NF-HYP) or (b) a relaxation control condition (RLX-HYP). Eighteen participants completed all treatment sessions and assessments. NF-HYP participants reported greater reductions in pain than RLX-HYP participants. The findings provide support for the potential treatment-enhancing effects of neurofeedback on hypnotic analgesia and also suggest that effective hypnosis treatment can be provided very efficiently.

A Disproportionate Burden of Care: Gender Differences in Mental Health, Health-Related Quality of Life, and Social Support in Mexican Multiple Sclerosis Caregivers

BACKGROUND

Multiple sclerosis (MS) rates in Latin America are increasing, and caregivers there experience reduced mental and physical health. Based on rigid gender roles in Latin America, women more often assume caregiving duties, yet the differential impact on women of these duties is unknown.

METHODS

This study examined gender differences in mental health (Patient Health Questionnaire-9, Satisfaction with Life Scale, Rosenberg Self-Esteem Scale, State-Trait Anxiety Inventory, and Zarit Burden Inventory), health-related quality of life (HRQOL; Short Form-36), and social support (Interpersonal Support Evaluation List-12) in 81 (66.7% women) Mexican MS caregivers.

RESULTS

As compared to men caregivers, women had lower mental health (p = 0.006), HRQOL (p < 0.001), and social support (p < 0.001). This was partially explained by women caregivers providing care for nearly twice as many hours/week as men (79.28 versus 48.48, p = 0.018) and for nearly three times as many months (66.31 versus 24.30, p = 0.002).

CONCLUSIONS

Because gender roles in Latin America influence women to assume more substantial caregiving duties, MS caregiver interventions in Latin America-particularly for women caregivers-should address the influence of gender-role conformity on care and psychosocial functioning.

Social disruption alters pain and cognition in an animal model of multiple sclerosis

Although pain and cognitive deficits are widespread and debilitating symptoms of multiple sclerosis (MS), they remain poorly understood. Theiler's murine encephalomyelitis virus (TMEV) infection is an animal model of MS where disease course is exacerbated by prior stressors. Here chronic infection coupled with prior social stress increased pain behavior and impaired hippocampal-dependent memory consolidation during the demyelinating phase of disease in SJL mice. These results suggest that the TMEV model may be useful in investigating pain and cognitive impairments in MS. However, in contrast to prior Balb/cJ studies, stress failed to consistently alter behavioral and physiological indicators of disease course.

A pain-mediated neural signal induces relapse in murine autoimmune encephalomyelitis, a multiple sclerosis model

Although pain is a common symptom of various diseases and disorders, its contribution to disease pathogenesis is not well understood. Here we show using murine experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS), that pain induces EAE relapse. Mechanistic analysis showed that pain induction activates a sensory-sympathetic signal followed by a chemokine-mediated accumulation of MHC class II+CD11b+ cells that showed antigen-presentation activity at specific ventral vessels in the fifth lumbar cord of EAE-recovered mice. Following this accumulation, various immune cells including pathogenic CD4+ T cells recruited in the spinal cord in a manner dependent on a local chemokine inducer in endothelial cells, resulting in EAE relapse. Our results demonstrate that a pain-mediated neural signal can be transformed into an inflammation reaction at specific vessels to induce disease relapse, thus making this signal a potential therapeutic target.

DOI:http://dx.doi.org/10.7554/eLife.08733.001

Multiple sclerosis (or MS for short) is a disease in which the insulating covers of nerve cells in the brain and spinal cord become inflamed and damaged. Depending on which nerves are affected, this disease can cause a wide range of symptoms, ranging from numbness and muscle spasms to visual disturbances and chronic pain. Many other diseases and disorders also have pain as a symptom, but it is not well understood if pain itself can directly contribute to the development of disease.

Most people with MS will, initially, experience periods when their symptoms get worse (called ‘relapses’), which are then followed by periods of improvement. Arima, Kamimura et al. investigated whether the sensation of pain itself could trigger a relapse in a mouse model of MS. The experiments showed that a painful sensation could trigger a relapse in the mice via the so-called ‘gateway reflex’. This reflex describes the phenomenon whereby nerve impulses lead to the release of signaling molecules that cause the walls of nearby blood vessels to open and allow immune cells to move from the bloodstream to the central nervous system. This in turn stimulates the development of inflammation, which causes an imbalance in the affected sites of the central nervous system.

These findings demonstrate that pain itself triggers a signal—sent via nerve impulses followed by the release of signaling molecules—that can lead to a relapse; and suggest that interfering with this signal could potentially help to treat to protect against relapses in MS. Following on from this work, it will be important to confirm if the gateway reflex exists in humans, and whether it is linked to other diseases that don't involve the central nervous system.

DOI:http://dx.doi.org/10.7554/eLife.08733.002

Cognitive Impairment and Community Integration Outcomes in Individuals Living With Multiple Sclerosis

OBJECTIVES

To determine the association between unique domains of cognitive impairment and community integration in individuals with multiple sclerosis (MS), and to determine the contributions of cognitive impairment to community integration beyond the influence of demographic and clinical variables.

DESIGN

Cross-sectional analysis of objective neuropsychological assessment and self-report data. Data were collected during baseline assessment of a randomized, multisite controlled trial of ginkgo biloba for cognitive impairment in MS. Hierarchical regression analyses examined the association between subjective and objective measures of cognitive impairment and 3 domains of community integration, adjusting for relevant covariates.

SETTING

Two Veterans Affairs medical center MS clinics.

PARTICIPANTS

Adults (N=121; ages 24-65y) with a confirmed MS diagnosis.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Primary outcomes were scores on the Home Integration (CIQ-H), Social Integration (CIQ-S), and Productivity (CIQ-P) domains of the Community Integration Questionnaire (CIQ).

RESULTS

Cognitive impairment was associated with lower scores on the CIQ-H and CIQ-S, but not the CIQ-P. Greater levels of subjective cognitive impairment were associated with lower scores on the CIQ-H and CIQ-S. Greater levels of objective cognitive impairment, specifically slower processing speed and poorer inhibitory control, were related to lower CIQ-S scores. Subjective and objective measures of cognitive impairment were significantly and independently associated with CIQ-S.

CONCLUSIONS

Objective cognitive impairment may interfere with participation in social activities. Subjective cognitive impairment is also important to assess, because individuals who perceive themselves to be cognitively impaired may be less likely to participate in both home and social activities. Clinical interventions to enhance community integration in individuals with MS may benefit from addressing objective and subjective cognitive impairment by integrating cognitive rehabilitation approaches with self-efficacy-enhancing strategies.

Beyond a physical symptom: the importance of psychosocial factors in multiple sclerosis pain

BACKGROUND AND PURPOSE

Pain affects around two-thirds of people with Multiple Sclerosis (pwMS). Biomedical treatments show limited efficacy. A recently developed cognitive-behavioural model of Multiple Sclerosis (MS) pain suggests several psychosocial factors may worsen pain and related disability. The current study investigated whether psychosocial factors drawn from this model explain significant amounts of the variance in pain severity and interference over and above measures of disease severity and pain subtype.

METHODS

Six hundred and twelve pwMS experiencing pain completed a U.K. wide cross-sectional survey including valid and reliable psychometric questionnaires. Hierarchical regressions determined the relative contribution of disease severity and psychosocial factors to predicting pain severity and interference.

RESULTS

All psychosocial factors including distress, negative beliefs about pain and its consequences, and avoidance of activity, were related to pain outcomes, explaining a further 24% and 30% of the variance in pain severity and interference after controlling for demographic and disease variables. Findings were similar for neuropathic and non-neuropathic pain subgroups.

CONCLUSIONS

All pwMS reported significant pain and associated disability even though over 90% were taking pain medication. Psychosocial factors identified as important in predicting pain severity and, to a greater extent, pain interference are potentially modifiable and may be important treatment targets for both pain subtypes.

An examination of the psychometric properties of the community integration questionnaire (CIQ) in spinal cord injury

OBJECTIVE

To examine the psychometric properties of the Community Integration Questionnaire (CIQ) in large samples of individuals with spinal cord injury (SCI).

DESIGN

Longitudinal 12-month survey study.

SETTING

Nation-wide, community dwelling.

PARTICIPANTS

Adults with SCI: 627 at Time 1, 494 at Time 2.

INTERVENTIONS

Not applicable.

OUTCOME MEASURES

The CIQ is a 15-item measure developed to measure three domains of community integration in individuals with traumatic brain injury: home integration, social integration, and productive activity. SCI consumer input suggested the need for two additional items assessing socializing at home and internet/email activity.

RESULTS

Exploratory factor analyses at Time 1 indicated three factors. Time 2 confirmatory factor analysis did not show a good fit of the 3-factor model. CIQ scores were normally distributed and only the Productive subscale demonstrated problems with high (25%) ceiling effects. Internal reliability was acceptable for the Total and Home scales, but low for the Social and Productive activity scales. Validity of the CIQ is suggested by significant differences by sex, age, and wheelchair use.

CONCLUSIONS

The factor structure of the CIQ was not stable over time. The CIQ may be most useful for assessing home integration, as this is the subscale with the most scale stability and internal reliability. The CIQ may be improved for use in SCI by including items that reflect higher levels of productive functioning, integration across the life span, and home- and internet-based social functioning.

The impact of pain on health-related quality of life 3 months after stroke

BACKGROUND

Pain is common in stroke; however, its impacts on health-related quality of life (HRQoL) are unclear due to the limitations of previous studies.

OBJECTIVES

The current study aims to examine and compare the demographic and clinical characteristics of Chinese stroke patients with and without pain and explore the correlations between poststroke pain and HRQoL.

METHOD

Four hundreds and forty-one participants recruited in an acute stroke unit in a regional hospital. They were assessed 3 months after the index stroke with the following instruments. HRQoL was measured using the Short Form-12 (SF-12). The Chinese version of the Faces Pain Rating Scale-Revised (FPS-R) was used to determine the presence and intensity of pain. The demographic and clinical characteristics of patients were obtained using Barthel Index (BI), Fatigue Severity Scale (FSS), Geriatric Depression Scale (GDS), Anxiety subscale of the Hospital Anxiety and Depression Scale (HADSA), Instrumental Activities of Daily Living (IADL), Mini Mental State Examination (MMSE), Modified Rankin Scale (MRS), and National Institutes of Health Stroke Scale (NIHSS).

RESULTS

Of all participants screened, 167 reported pain and 69 had novel pain. The pain group had significantly lower physical component summary (PCS) scores after adjusting for sex, education, DSM-IV depression and BI, GDS, HADSA, and FSS scores. The FPS score was negatively correlated with a lower PCS score in patients with pain and with novel pain.

CONCLUSION

The presence and intensity of pain have significant negative effects on HRQoL in stroke survivors. Interventions for pain could make a valuable contribution to improving HRQoL in stroke survivors.

Utilization and patients' perceptions of the effectiveness of pain treatments in multiple sclerosis: A cross-sectional survey

BACKGROUND

Although chronic pain is common among persons with multiple sclerosis (MS), little is known about the utilization and patients' perception of the effectiveness of pain treatments in MS.

OBJECTIVES

The objectives were to: (1) identify specific treatments currently used for pain relief by adults with MS; (2) examine patients' perceptions of the effectiveness of each of these treatments; and (3) examine rates of health care utilization, specifically provider and emergency department visits, for pain.

DESIGN

Cross-sectional survey.

METHODS

One hundred twenty-five community-dwelling participants with MS and pain completed a postal survey that measured demographics, MS disease, pain, pain treatments, perceived effectiveness of treatments, and health care utilization.

RESULTS

The majority (89.6%) of the sample reported use of a variety of and multiple pain treatments (range = 1-19, median = 9.0, mean = 9.0, SD = 4.2); few were rated as providing pain relief. Non-prescription pain relievers were the most commonly reported treatment. Physical treatment modalities were also common. The treatments that were reported by patients to provide the greatest pain relief, such as hypnosis, nerve blocks, and marijuana, were not those that were the most frequently used. Overall, 75% reported at least one visit to a provider for pain in the past six months; participants made, on average, 9.7 visits for pain during this same time period. Emergency department visits explicitly for pain were reported by 11% of respondents.

CONCLUSIONS

These findings suggest that pain is inadequately treated from the perspective of persons with MS and results in a high level of health care utilization.