Acute and chronic pain syndromes in multiple sclerosis

Insomnia and fibromyalgia-like symptoms among women diagnosed with relapsing remitting multiple sclerosis in Jordan: Prevalence and correlates

OBJECTIVE

This study examined the prevalence and correlates of fibromyalgia and insomnia in a convenience sample of Women with Multiple Sclerosis (WMS).

METHODS

The study was cross-sectional in design and recruited a sample of 163 women with Relapsing-Remitting Multiple Sclerosis (RRMS). Fibromyalgia was assessed using the Patient Self-Report Survey (PSRS), which follows criteria outlined by the American College of Rheumatology. Insomnia was measured using the Arabic version of the Insomnia Severity Index (ISI-A).

RESULTS

The prevalence of fibromyalgia and insomnia was 28.2% (n = 46) and 46.3% (n = 76), respectively. Multivariate analyses were used to determine significant independent correlates. Fibromyalgia was associated with age above 40 years (OR = 2.29, 95% CI = 1.01-5.18, P = .04), high school education (OR = 3.69, 95% CI = 1.62-8.37, P = .002), and non-use of analgesics (OR = .02, 95% CI = .004-.21, P = .001). Insomnia symptoms were significantly associated only with age above 40 years (OR = 2.16, 95% CI = 1.16-4.04, P = .01).

CONCLUSION

These findings highlight the need for increased attention by primary care physicians towards diagnosing and treating fibromyalgia and insomnia among women with RRMS in Jordan, particularly for older women.

Glial cells and neurologic autoimmune disorders

Neurologic autoimmune disorders affect people's physical and mental health seriously. Glial cells, as an important part of the nervous system, play a vital role in the occurrence of neurologic autoimmune disorders. Glial cells can be hyperactivated in the presence of autoantibodies or pathological changes, to influence neurologic autoimmune disorders. This review is mainly focused on the roles of glial cells in neurologic autoimmune disorders and the influence of autoantibodies produced by autoimmune disorders on glial cells. We speculate that the possibility of glial cells might be a novel way for the investigation and therapy of neurologic autoimmune disorders.

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.

Pain Characteristics and Associations with Quality of Life in Patients with Multiple Sclerosis in Lithuania

Background and objectives: Even though pain in multiple sclerosis (MS) patients is common and possibly associated with reduced quality of life, its exact prevalence and characteristics remain vaguely understood. We aimed to estimate the true extent of pain and its associations with quality of life in Lithuanian MS patients and to compare this data with that of a control group. Materials and Methods: Data were collected prospectively at the Department of Neurology, Lithuanian University of Health Sciences Kaunas Clinics. A face-to-face structured interview and a questionnaire were used to collect demographic and clinical data of the MS (n = 120) and control (n = 120) groups. The Expanded Disability Status Scale (EDSS) was used to quantify disability in the MS group. Scores ≥4/10 in the Douleur Neuropathique 4 questionnaire were classified as neuropathic pain. Patients were evaluated using the anxiety and depression subsets of the Hospital Anxiety and Depression Scale (HADS-A and HADS-D), the physical and mental component subsets of the Short Form-12 questionnaire (PSC-12 and MSC-12). Results: The MS and control groups did not differ in pain prevalence (76.7% vs. 65.9%, p = 0.064) or intensity. Lhermitte sign, lower limb, and face pain were more common in the MS group, whereas subjects in the control group were more often affected by lower back, neck, and joint pain. Neuropathic pain and pain lasting longer than 2 years were more common among pain-affected MS patients than among controls. MS patients with pain had higher EDSS, HADS-D, and HADS-A and lower PSC-12 scores than those without pain; however, no difference was found regarding the duration of MS or age. Males with MS and pain had higher MSC-12 and HADS-D scores in comparison to the same subset of females. Conclusions: Pain affects approximately three out of four patients with MS in Lithuania and is negatively associated with the mental and physical aspects of quality of life.

Low back pain in patients with multiple sclerosis: A systematic review and the prevalence in a French multiple sclerosis population

PURPOSE

The prevalence and management of back pain in MS patients was assessed by a systematic review, and the results of a survey on the characteristics of low back pain in a sample of French MS patients are reported.

METHODS

A systematic search was conducted according to the PRISMA guidelines. The outcomes of interest included the prevalence of back pain, severity of pain and impact on daily activities. Moreover, the prevalence of low back pain and its consequences on daily living in a large French MS population were assessed.

RESULTS

Fourteen studies were included in the systematic review. The prevalence of back pain in MS patients ranged from 8.6 to 50%, but that of low back pain in particular ranged from 41.6 to 52.4%. Concerning the survey, 237 patients participated in the online questionnaire. The prevalence of low back pain in the French MS patients was 76.4%. The patients with chronic low back pain had more limitations in their daily life activities than those without chronic low back pain.

CONCLUSION

Patients with MS commonly suffer from low back pain, but it is still an underdiagnosed cause of pain that reduces one's ability to perform activities in daily life.

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.

Non-pharmacological interventions for chronic pain in multiple sclerosis

BACKGROUND

Chronic pain is common and significantly impacts on the lives of persons with multiple sclerosis (pwMS). Various types of non-pharmacological interventions are widely used, both in hospital and ambulatory/mobility settings to improve pain control in pwMS, but the effectiveness and safety of many non-pharmacological modalities is still unknown.

OBJECTIVES

This review aimed to investigate the effectiveness and safety of non-pharmacological therapies for the management of chronic pain in pwMS. Specific questions to be addressed by this review include the following.Are non-pharmacological interventions (unidisciplinary and/or multidisciplinary rehabilitation) effective in reducing chronic pain in pwMS?What type of non-pharmacological interventions (unidisciplinary and/or multidisciplinary rehabilitation) are effective (least and most effective) and in what setting, in reducing chronic pain in pwMS?

SEARCH METHODS

A literature search was performed using the specialised register of the Cochrane MS and Rare Diseases of the Central Nervous System Review Group, using the Cochrane MS Group Trials Register which contains CENTRAL, MEDLINE, Embase, CINAHL, LILACUS, Clinical trials.gov and the World Health Organization International Clinical Trials Registry Platform on 10 December 2017. Handsearching of relevant journals and screening of reference lists of relevant studies was carried out.

SELECTION CRITERIA

All published randomised controlled trials (RCTs)and cross-over studies that compared non-pharmacological therapies with a control intervention for managing chronic pain in pwMS were included. Clinical controlled trials (CCTs) were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

All three review authors independently selected studies, extracted data and assessed the methodological quality of the studies using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) tool for best-evidence synthesis. Pooling data for meta-analysis was not possible due to methodological, clinical and statistically heterogeneity of the included studies.

MAIN RESULTS

Overall, 10 RCTs with 565 participants which investigated different non-pharmacological interventions for the management of chronic pain in MS fulfilled the review inclusion criteria. The non-pharmacological interventions evaluated included: transcutaneous electrical nerve stimulation (TENS), psychotherapy (telephone self-management, hypnosis and electroencephalogram (EEG) biofeedback), transcranial random noise stimulation (tRNS), transcranial direct stimulation (tDCS), hydrotherapy (Ai Chi) and reflexology.There is very low-level evidence for the use of non-pharmacological interventions for chronic pain such as TENS, Ai Chi, tDCS, tRNS, telephone-delivered self-management program, EEG biofeedback and reflexology in pain intensity in pwMS. Although there were improved changes in pain scores and secondary outcomes (such as fatigue, psychological symptoms, spasm in some interventions), these were limited by methodological biases within the studies.

AUTHORS' CONCLUSIONS

Despite the use of a wide range of non-pharmacological interventions for the treatment of chronic pain in pwMS, the evidence for these interventions is still limited or insufficient, or both. More studies with robust methodology and greater numbers of participants are needed to justify the effect of these interventions for the management of chronic pain in pwMS.

Association Between Pain and Mindfulness in Multiple Sclerosis: A Cross-sectional Survey

BACKGROUND

Chronic pain is a common symptom in people with multiple sclerosis (MS) and often requires a multimodal approach to care. The practice of mindfulness has been shown to decrease the experience of pain in other conditions, yet little is known about the relationship between mindfulness and pain in people with MS. The objective of this study was to evaluate the association between pain interference and trait mindfulness in people with MS.

METHODS

In this cross-sectional survey, 132 people with any type of MS completed the Patient-Reported Outcomes Measurement Information System Pain Interference scale and the Five Facet Mindfulness Questionnaire. Linear regression was used to test the association between pain and mindfulness while adjusting for demographic and MS-related characteristics.

RESULTS

The relationship between pain and mindfulness was clinically meaningful and highly significant (t = -5.52, P < .0001). For every 18-point increase in mindfulness scores, pain interference scores are expected to decrease by 3.96 (95% CI, -2.52 to -5.40) points (β = -0.22, P < .0001). The adjusted model, including age, type of MS, the interaction between mindfulness and age, and the interaction between mindfulness and MS type, explains 26% of the variability in pain interference scores (R2 = 0.26).

CONCLUSIONS

These results suggest a clinically significant association between mindfulness and pain interference in MS and support further exploration of mindfulness-based interventions in the management of MS-related pain.

CaMKIIα Mediates the Effect of IL-17 To Promote Ongoing Spontaneous and Evoked Pain in Multiple Sclerosis

Pain is a common and severe symptom in multiple sclerosis (MS), a chronic inflammatory and demyelinating disease of the CNS. The neurobiological mechanism underlying MS pain is poorly understood. In this study, we investigated the role of Ca²⁺/calmodulin-dependent protein kinase IIα (CaMKIIα) in driving chronic pain in MS using a mouse experimental autoimmune encephalomyelitis (EAE) model. We found that spinal CaMKIIα activity was enhanced in EAE, correlating with the development of ongoing spontaneous pain and evoked hypersensitivity to mechanical and thermal stimuli. Prophylactic or acute administration of KN93, a CaMKIIα inhibitor, significantly reduced the clinical scores of EAE and attenuated mechanical allodynia and thermal hyperalgesia in EAE. siRNA targeting CaMKIIα reversed established mechanical and thermal hypersensitivity in EAE mice. Furthermore, CaMKIIαT286A point mutation mice showed significantly reduced EAE clinical scores, an absence of evoked pain, and ongoing spontaneous pain when compared with littermate wild-type mice. We found that IL-17 is responsible for inducing but not maintaining mechanical and thermal hyperalgesia that is mediated by CaMKIIα signaling in EAE. Together, these data implicate a critical role of CaMKIIα as a cellular mechanism for pain and neuropathy in multiple sclerosis and IL-17 may act upstream of CaMKIIα in the generation of pain.SIGNIFICANCE STATEMENT Pain is highly prevalent in patients with multiple sclerosis (MS), significantly reducing patients' quality of life. Using the experimental autoimmune encephalomyelitis (EAE) model, we were able to study not only evoked hyperalgesia, but also for the first time to demonstrate spontaneous pain that is also experienced by patients. Our study identified a role of spinal CaMKIIα in promoting and maintaining persistent ongoing spontaneous pain and evoked hyperalgesia pain in EAE. We further demonstrated that IL-17 contributes to persistent pain in EAE and functions as an upstream regulator of CaMKIIα signaling. These data for the first time implicated CaMKIIα and IL-17 as critical regulators of persistent pain in EAE, which may ultimately offer new therapeutic targets for mitigating pain in multiple sclerosis.

The scope and nature of pain in persons with multiple sclerosis

Much remains unknown about the scope, nature, and impact of pain on the lives of persons with multiple sclerosis (MS). In the present study, 180 community dwelling adults with MS completed a postal survey that included demographic measures, MS disease measures, and several standardized measures of pain, including pain intensity, variability, location, and pain-related interference. Some 66% of the sample reported pain, 25% of whom reported severe pain. Persons with pain reported an average of 6.6 distinct pain sites. Using the Brief Pain Inventory Interference Scale, the average level of overall pain interference was 3.33 (0- 10 scale) in the group reporting pain. The highest levels of pain interference were reported for sleep, recreational activities, and work in and outside the home. Persons with pain were more likely to report greater MS disease severity, poorer psychological functioning, and poorer health than persons with MS but not pain. Persons with pain were also less likely to be employed. These findings are consistent with previous research that shows that pain is common in MS, that it is severe in a substantial subset of these individuals and has the potential to negatively impact physical and psychosocial functioning over and above the effects of MS itself.

Pain and affective memory biases interact to predict depressive symptoms in multiple sclerosis

A large literature supports a direct relationship between pain and depressive symptoms among various patient populations. Patients with multiple sclerosis (MS) frequently experience both pain and depression. Despite this, no relationship between pain and depression has been found in MS. The present investigation explored the relationship between pain and depression in a sample of patients with MS. Consistent with cognitive theories of depression, results supported the hypothesis that pain would only contribute to depression when MS patients exhibited a concomitant cognitive vulnerability. Cognitive vulnerability to depression was measured using a performance based affective memory bias (AMB) task. Patients with high levels of pain and negative AMB reported more depressive symptoms compared to patients with pain and positive AMB. Implications for the identification and treatment of depression in MS are discussed.

The Prevalence of Pain in Adults with Multiple Sclerosis: A Multicenter Cross-Sectional Survey

OBJECTIVE

Examination of prevalence, intensity and associations of pain in persons with multiple sclerosis (MS).

DESIGN

Multicenter, international cross-sectional survey.

SETTING

Patients were recruited from seven MS centers: in Serbia (Clinic of Neurology, Clinical Center of Serbia, Belgrade; Clinic of Neurology, Military Medical Academy, Belgrade; Clinic of Neurology, Clinical Center Kragujevac; Clinic of Neurology, Clinical Center Nis; Department of Neurology, General Hospital-Uzice), in Republic of Srpska-Bosnia and Herzegovina (Clinic of Neurology, Clinical Center Banja Luka) and in Croatia (University Department of Neurology, Sestre Milosrdnice University Hospital Center, Zagreb).

SUBJECTS

Six hundred and fifty consecutive MS patients diagnosed according to the Revised McDonald criteria (2005), from the aforementioned centers, over the period of 6 months.

METHODS

A semistructured questionnaire was administered during a face-to-face interview with neurologists who also performed Expanded Disability Status Scale (EDSS), the Hamilton Rating Scale for Depression (HDRS) and Hamilton Rating Scale for Anxiety (HARS). To recognize predictive factors for the presence of pain, the linear regression analysis was used.

RESULTS

Lifetime prevalence of pain was 66.5% (point prevalence = 44.3%). The prevalence of the comorbidity of pain and depression was 29.1%. Older age (P < 0.001), primary-progressive MS (P = 0.034), higher EDSS score (P = 0.008), higher scores of HDRS (P < 0.001), and HARS (P < 0.001) were significantly associated with pain. Finally, in our multivariate linear regression analysis, anxiety (P < 0.001) was the independent predictor of pain.

CONCLUSIONS

We confirmed high prevalence of pain, affecting approximately more than half of patients during the course of MS. Pain in MS is associated with disability, depression and, especially with anxiety, which has significant implications for treatment.

Towards a better understanding of MS pain: a systematic review of potentially modifiable psychosocial factors

OBJECTIVE

Pain is a common symptom of Multiple Sclerosis (MS). Biomedical treatments achieve only modest reductions in pain severity suggesting that this approach may be too narrow. The aim of this systematic review was to assess evidence for associations between modifiable psychosocial factors and MS pain severity and pain interference and use this evidence to develop a preliminary biopsychosocial model of MS pain.

METHODS

Empirical studies of pain in MS utilising standardised pain severity and pain interference measures were included. Online databases (Cochrane, PsychInfo, EMBASE, CINAHL, Medline, Web of Science and World Cat) and reference sections of included articles were searched, and corresponding authors contacted to identify unpublished studies. Information about design, sample size, MS type, time since diagnosis, psychosocial and pain measures and key findings were extracted. Thirty-one studies were assessed for quality and a narrative synthesis was conducted.

RESULTS

Similar to primary chronic pain, most studies reported small to medium associations between several psychosocial factors and pain severity and interference. Pain catastrophizing showed consistently strong associations with pain interference. Preliminary findings revealed a strong correlation between pain acceptance and pain interference. However, fear-avoidance appeared less important in MS, and other forms of behavioural avoidance were not explored.

CONCLUSIONS

A preliminary model of MS pain outlining specific psychosocial factors is presented with a conceptual formulation from both traditional, and contextual, cognitive-behavioural perspectives. Pain catastrophizing, acceptance, and endurance, as opposed to fear avoidance, responses are highlighted as potentially important treatment targets in MS, and directions for future research are outlined.

‘It feels like someone is hammering my feet’: Understanding pain and its management from the perspective of people with multiple sclerosis

Background:

Pain affects around 63% of people with multiple sclerosis (pwMS). Biomedical treatments demonstrate limited efficacy. More research is needed to understand pain from the individual’s perspective in order to better inform a patient-centred approach that improves engagement, self-management and outcome.

Objective:

The objective of this paper is to explore pwMS’ experience and responses to pain, and their perspectives on pain management.

Methods:

Twenty-five in-depth, semi-structured telephone interviews were conducted. Interviews were audiotaped, transcribed and analysed using an inductive thematic analysis approach with elements of grounded theory.

Results:

Key themes included vivid descriptions of pain and beliefs that pain is unpredictable, a sign of damage and may worsen. Anger was a common emotional response. Two dominant pain management themes emerged: one related to pain reduction and another to acceptance. Those focusing on pain reduction appeared to engage in cycles in which they struggled with symptoms and experienced continued distress.

Conclusion:

Findings identify pain-related beliefs, emotional reactions and disparate pain-management attitudes. All may influence pwMS’ responses to pain and what they ask of their clinicians. Uncovering pwMS’ personal beliefs about pain, and introducing a broader biopsychosocial understanding of pain in the clinical context, may provide opportunities to rectify potentially unhelpful management choices and enhance pain acceptance.

Satellite glial cells in dorsal root ganglia are activated in experimental autoimmune encephalomyelitis

Pain is a serious and common problem with patients suffering from multiple sclerosis (MS). Very little has been done to investigate the peripheral mechanisms of pain in MS. Here we used a mouse model of experimental autoimmune encephalomyelitis (EAE) to investigate the possible contribution of satellite glial cells (SGCs) to pain in MS. EAE mice had reduced pain thresholds 10 days after disease induction. We examined dorsal root ganglia and found increased expression of glial fibrillary acidic protein in SGCs, a marker of SGC activation, and increased coupling among SGCs, a known component of activated SGCs. Activated SGCs have previously been shown to contribute to pain in other classical neuropathic pain models, suggesting that pain in multiple sclerosis has a peripheral component.

Mechanisms and pharmacology of neuropathic pain in multiple sclerosis

The neuropathic pain of multiple sclerosis is quite prevalent and severely impacts quality of life. A few randomized, placebo-controlled, blinded clinical trials suggest that cannabis- and anticonvulsant-based treatments provide partial pain relief, but at the expense of adverse events. An even smaller, but emerging, number of translational studies are using rodent models of experimental autoimmune encephalomyelitis (EAE), which exhibit pain-like behaviors resembling those of Multiple sclerosis (MS) patients. These studies not only support the possible effectiveness of anticonvulsants, but also compel further clinical trials with serotonin-norepinephrine reuptake inhibitors, the immunosuppressant drug rapamycin, or drugs which interfere with glutamatergic neurotransmission. Future behavioral studies in EAE models are essential toward a new pharmacotherapy of multiple sclerosis pain.

Pharmacological treatment of pain in multiple sclerosis

Pain is a common symptom in multiple sclerosis (MS) and was recently estimated to be experienced by up to 75% of patients. Nociceptive and neuropathic pain in MS may be present concurrently and at different stages of the disease and may be associated with other symptoms. Evidence for treating pain in MS is limited. Many clinical features of pain are often unrecognized by clinicians and are difficult for patients to describe. Treatment is often based on anecdotal reports and clinical experience. We present a review of treatment options for pain in MS that should serve to update current knowledge, highlight shortcomings in clinical research and provide indications towards achieving evidence-based treatment of pain in MS.

Symptomatic treatment and management of multiple sclerosis

The range of symptoms which occur in multiple sclerosis (MS) can have disabling functional consequences for patients and lead to significant reductions in their quality of life. MS symptoms can also interact with each other, making their management challenging. Clinical trials aimed at identifying symptomatic therapies have generally been poorly designed and have tended to be underpowered. Therefore, the evidence base for the management of MS symptoms with pharmacologic therapies is not strong and tends to rely upon open-label studies, case reports, and clinical trials with small numbers of patients and poorly validated clinical outcome measures. Recently, there has been a growing interest in the management of MS symptoms with pharmacologic treatments, and better-designed, randomized, double-blind, controlled trials have been reported. This chapter will describe the evidence base predominantly behind the various pharmacologic approaches to the management of MS symptoms, which in most, if not all, cases, requires multidisciplinary input. Drugs routinely recommended for individual symptoms and new therapies, which are currently in the development pipeline, will be reviewed. More interventional therapies related to symptoms that are refractory to pharmacotherapy will also be discussed, where relevant.

Pain management in neurocritical care

The core challenge of pain management in neurocritical care is to keep the patient comfortable without masking or overlooking any neurological deterioration. Clearly in patients with a neurological problem there is a conflict of clinical judgement and adequate pain relief. Here we review the presentation, assessment, and development of pain in the clinical spectrum of patients with associated neurological problems seen in a general intensive care setting. Many conditions predispose to the development of chronic pain. There is evidence that swift and targeted pain management may improve the outcome. Importantly pain management is multidisciplinary. The available non-invasive, pharmacological, and invasive treatment strategies are discussed.

Pain in experimental autoimmune encephalitis: a comparative study between different mouse models

BACKGROUND

Pain can be one of the most severe symptoms associated with multiple sclerosis (MS) and develops with varying levels and time courses. MS-related pain is difficult to treat, since very little is known about the mechanisms underlying its development. Animal models of experimental autoimmune encephalomyelitis (EAE) mimic many aspects of MS and are well-suited to study underlying pathophysiological mechanisms. Yet, to date very little is known about the sensory abnormalities in different EAE models. We therefore aimed to thoroughly characterize pain behavior of the hindpaw in SJL and C57BL/6 mice immunized with PLP139-151 peptide or MOG35-55 peptide respectively. Moreover, we studied the activity of pain-related molecules and plasticity-related genes in the spinal cord and investigated functional changes in the peripheral nerves using electrophysiology.

METHODS

We analyzed thermal and mechanical sensitivity of the hindpaw in both EAE models during the whole disease course. Qualitative and quantitative immunohistochemical analysis of pain-related molecules and plasticity-related genes was performed on spinal cord sections at different timepoints during the disease course. Moreover, we investigated functional changes in the peripheral nerves using electrophysiology.

RESULTS

Mice in both EAE models developed thermal hyperalgesia during the chronic phase of the disease. However, whereas SJL mice developed marked mechanical allodynia over the chronic phase of the disease, C57BL/6 mice developed only minor mechanical allodynia over the onset and peak phase of the disease. Interestingly, the magnitude of glial changes in the spinal cord was stronger in SJL mice than in C57BL/6 mice and their time course matched the temporal profile of mechanical hypersensitivity.

CONCLUSIONS

Diverse EAE models bearing genetic, clinical and histopathological heterogeneity, show different profiles of sensory and pathological changes and thereby enable studying the mechanistic basis and the diversity of changes in pain perception that are associated with distinct types of MS.

Long-term follow-up of microvascular decompression for trigeminal neuralgia

We conducted a study to evaluate the follow-up characteristics of patients with trigeminal neuralgia (TN) and to evaluate the factors affecting long-term outcome of microvascular decompression (MVD) in TN. Between 1983 and 2003, 156 patients with TN treated with MVD by 4 neurosurgeons at University Medical Centre Groningen/the Netherlands were evaluated. Baseline data from operative outcome were evaluated using univariate and multivariate analysis. The group consisted of 156 patients with TN: 90 females and 66 males with a median follow-up period of 9.7 years. The average age of initial symptoms was 51 years. The average duration of symptoms was 58 months. Postoperative 22 patients had a facial hyperpathia or hyperesthesia. Postoperatively, 137 patients had immediate relief. Postoperatively 1 year, 140 patients still had a good outcome of the operation. Twenty-seven patients with good immediate postoperative results had recurrent pain. From the group of patients with typical TN, 82% had good long-term results after operation. Patients with typical TN and immediate postoperative remission, in univariate analysis, had significantly more often an excellent/good postoperative outcome. Immediate postoperative remission is an independent predictive factor for a good long-term outcome. The long-term results of MVD in majority of patients were good with no mortalities and no major morbidities. Patients with typical TN had better long-term outcomes and less recurrence.

Pain in patients with multiple sclerosis: a complex assessment including quantitative and qualitative measurements provides for a disease-related biopsychosocial pain model

Background:

Pain of various causes is a common phenomenon in patients with Multiple Sclerosis (MS). A biopsychosocial perspective has proven a useful theoretical construct in other chronic pain conditions and was also started in MS. To support such an approach, we aimed to investigate pain in MS with special emphasis on separating quantitative and qualitative aspects, and its interrelation to behavioral and physical aspects.

Materials and methods:

Pain intensity (NRS) and quality (SES) were measured in 38 consecutive outpatients with MS (mean age, 42.0 ± 11.5 years, 82% women). Pain-related behavior (FSR), health care utilization, bodily complaints (GBB-24) and fatigue (WEIMuS) were assessed by questionnaires, and MS-related neurological impairment by a standardized neurological examination (EDSS).

Results:

Mean pain intensity was 4.0 (range, 0–10) and mean EDSS 3.7 (range, 0–8) in the overall sample. Currently present pain was reported by 81.6% of all patients. Disease duration and EDSS did not differ between patients with and without pain and were not correlated to quality or intensity of pain. Patients with pain had significantly higher scores of musculoskeletal complaints, but equal scores of exhaustion, gastrointestinal and cardiovascular complaints. Pain intensity correlated only with physical aspects, whereas quality of pain was additionally associated with increased avoidance, resignation and cognitive fatigue.

Conclusion:

As in other conditions, pain in MS must be assessed in a multidimensional way. Further research should be devoted to adapt existing models to a MS-specific model of pain.

Rehabilitation challenges in multiple sclerosis

While current immunomodulating drugs aim to reduce multiple sclerosis (MS) exacerbations and slow disease progression, rehabilitation aims to improve and maintain the functional abilities of patients in the face of disease progression. An increasing number of journal articles are describing the value of the many rehabilitation interventions that can be used throughout the course of the disease, from the initial symptoms to the advanced stages. An integrated team of healthcare professionals is necessary to address a myriad of problems to reduce impairments, disabilities, and handicaps. The problems may be related to fatigue, weakness, spasticity, mobility, balance, pain, cognition, mood, relationships, bowel, bladder, sexual function, swallowing, speech, transportation, employment, recreation, and activities of daily living (ADL) such as dressing, eating, bathing, and household chores. The team can help prevent complications and secondary disabilities, while increasing patient safety. Improving neurologically related function, maintaining good relationships, and feeling productive and creative adds enormously to the quality of life of people with MS and their families. Rehabilitation is more than an 'extra' service that is given after medical therapies; it is an integral part of the management of the diverse set of problems encountered throughout the course of the disease. An interdisciplinary team may have many members, including physicians, nurses, physical therapists, occupational therapists, speech and language pathologists, psychotherapists, social workers, recreational therapists, vocational rehabilitation therapists, patients, families, and other caregivers.

Pain in portuguese patients with multiple sclerosis

Early reports often ignored pain as an important symptom in multiple sclerosis (MS). Pain prevalence figures in MS from European countries other than Portugal range between 40 and 65%. To our knowledge there is no published data in English on pain in MS in Portugal. We describe the demographic and clinical characteristics, with an emphasis on pain, of 85 MS patients followed-up in a Portuguese hospital, contributing to pain epidemiology in MS. Patients were interviewed sequentially after their regular appointments at the MS clinic; patients with pain completed The Brief Pain Inventory and The McGill Pain Questionnaire (MPQ). The prevalence of pain found was 34%. Headache and back pain were the most common anatomical sites described, followed by upper and lower limbs. Intensity of pain in an 11-point scale was, for the maximum pain intensity 6.7 ± 1.8, for the minimum pain intensity 2.2 ± 2.0, for the mean pain intensity 4.5 ± 1.5, and for the actual pain intensity 2.4 ± 2.9. Pain interfered significantly with general activity, mood, work, social relations, and enjoyment of life. All MS patients with pain employed words from both the sensory and affective categories of the MPQ to describe it. Patient pain descriptions’ included the word “hot-burning” in 59% of the cases, common in the report of central pain, but neuropathic pain medications were only used by 10% of them. Pain is an important symptom in Portuguese patients with MS, not only because of the high prevalence found, concordant with other European countries, but also because of its interference with quality-of-life.

MRI of the central nervous system in MS patients with and without pain

BACKGROUND

Central pain (CP) is a common symptom in MS. Multiple theories are present about the mechanism of CP. Previous studies suggested that lesion of the spinothalamic tract is a necessary condition for development of CP. No previous study has in detail evaluated the association between the specific site of demyelinations and the presence of CP in MS.

OBJECTIVE

The study aimed to evaluate the location of plaques in MS patients with CP including a group of MS patients without pain as a reference group.

METHODS

All patients underwent a bedside sensory examination and MRI of the brain and spinal cord. MR imaging was acquired on an 1.5 Tesla MR equipment. A trained neuroradiologist, blinded to pain status, evaluated the MRI.

RESULTS

Thirteen MS patients with CP and 10 MS patients without pain were included. Allodynia and/or dysesthesia were more frequent in pain patients (11/13 vs. 1/10, P<0.01). No difference was found in the number of patients with plaques in spinothalamic tract, dorsal column-medial lemniscus, dorsolateral funiculus, grey substance, thalamus or capsula interna. A non-significantly lower number of pain patients had lesions in thalamo-cortical pathways (8/13 vs. 10/10, P=0.027).

CONCLUSIONS

No association between CP and site of demyelinations was found, although a trend toward a higher prevalence of intact thalamo-cortical pathways was seen in pain patients. CP was associated with allodynia, suggesting central hyperexcitability.

Analysis of the pain in multiple sclerosis patients

INTRODUCTION

Despite pain being a disabling symptom in patients with multiple sclerosis (MS), its prevalence and characteristics are not well established. The aim of this study is to describe the characteristics and prevalence of pain in patients with MS, and to assess the associated clinical variables and radiological findings.

METHODS

We prospectively studied patients with MS. A structured questionnaire which evaluated depression symptoms, type of pain, location, intensity (defined according to a visual analogue scale (VAS) as severe (VAS 7-10), moderate (VAS 4-6) and mild (VAS 0-4), and pain therapy was recorded in patients who referred to pain at the time of interview. Protocol variables were demographic data, MS clinical forms (remitting-relapsing, progressive-secondary and progressive-primary), neurological dysfunction (defined according to EDSS scale), symptoms at onset, attack frequency, illness duration, disease modifying treatment, fatigue, spasticity, oligoclonal bands in CSF, visual evoked potentials, depression symptoms (Hamilton test) and presence of lesions in spinal cord MRI.

RESULTS

A total of 134 MS patients were included, and MRI was performed on 105 of them. Pain was reported by 74 (55%) patients and was most frequently neuropathic, located in limbs, severe and burning/spiky. Of these 28 (38%) received therapy for their pain, based predominantly in anti-inflammatory drugs. Patients with pain had a worse functional state (EDSS score, 4.5 [3-6] vs 1.5 [1-2], p<0.001), higher number of relapses (7.13±3.4 vs 3.75±2.9, p<0.001), progressive forms of MS (86.7% vs 13.3%, p<0.001), depression (91.9% vs 8.1%, p<0.001), spinal cord involvement at onset (79.2% vs 20.8%, p=0.009), spinal cord lesions by MRI (84.3% vs 15.7%, p<0.001) and longer duration of disease (14.6±7.8 vs 8.43±5.9 months, p<0.001). In a logistic regression model, the presence of lesions in spinal cord MRI (OR 3.5 [1.5-24.5]) and higher EDSS score (OR 1.7 [1.1-2.7]) were independently associated with pain.

CONCLUSIONS

Pain is a frequent disabling symptom in MS and is associated with disability and spinal cord lesions.

L-acetylcarnitine: a proposed therapeutic agent for painful peripheral neuropathies

During the past two decades, many pharmacological strategies have been investigated for the management of painful neuropathies. However, neuropathic pain still remains a clinical challenge. A combination of therapies is often required, but unfortunately in most cases adequate pain relief is not achieved. Recently, attention has been focused on the physiological and pharmacological effects of L-acetylcarnitine in neurological disorders. There are a number of reports indicating that L-acetylcarnitine can be considered as a therapeutic agent in neuropathic disorders including painful peripheral neuropathies. In this review article, we will examine the antinociceptive and the neuroprotective effects of Lacetylcarnitine as tested in clinical studies and in animal models of nerve injury.

Communicating about the experience of pain and fatigue in disability

PURPOSE

To examine the experiences of people with chronic disabling conditions as they communicate with health care providers about pain and fatigue.

METHOD

Twenty-three adults with a variety of chronic disabling conditions participated in 5 focus groups. The following issues were raised: tell me about your pain/fatigue; what things go along with pain/fatigue? how do you talk about pain/fatigue with your health care provider (HCP)? What should your HCP know that they do not ask you about?

RESULTS

Results of qualitative analysis suggested two major themes. The first theme was labeled "Putting it in words" and suggests that both pain and fatigue are described in many ways, including the dimensions of type, intensity, level of interference and temporal aspects. Participants reported difficulty with responding to a single question that asked them to assign a number to their level of pain or fatigue. The second theme was labeled, "Let's talk about it" and suggested that participants wanted HCPs "to listen and believe me when I describe my experience". They wanted to be asked about how pain or fatigue interferes with life and about compensatory strategies rather than being asked to rate symptom intensity. Participants wished to be viewed as experts and to be actively involved in decisions about their health care.

CONCLUSIONS

Pain and fatigue were viewed as having many facets that are associated in complex ways with other aspects of the health/disability condition. From the participants' perspective, assignment of a pain intensity rating does not represent the complexity of their pain experience. Suggestions are provided for HCPs when communicating about pain and fatigue with people with chronic conditions.

Multiple sclerosis: an update for oral health care providers

Multiple sclerosis (MS) is a chronic, inflammatory, demyelinating disease of the central nervous system. The disease mostly affects young adults and is increasing in prevalence and incidence. Multiple sclerosis is characterized by periods of activity and remission which, after numerous relapses, cause permanent neurologic deficits. Diagnosis of MS is based on patient history and clinical examination supplemented by the findings of radiologic and laboratory tests. Numerous motor and sensory disturbances occur in MS and may present in the orofacial region. This medical management update highlights issues that are important to the oral health care provider, including orofacial manifestations of MS and dental considerations for patients with MS.

Hypothalamic stimulation for trigeminal neuralgia in multiple sclerosis patients: efficacy on the paroxysmal ophthalmic pain

Trigeminal neuralgia is a disorder characterized by paroxysmal pain arising in one or more trigeminal branches; it is commonly reported in multiple sclerosis. In multiple sclerosis patients the ophthalmic branch may be frequently involved and the risks carried by neurosurgical ablative procedures are higher including major adverse effects such as corneal reflex impairment and keratitis. The objective of this works is to assess the role of posterior hypothalamus neuromodulation in the treatment of trigeminal neuralgia in multiple sclerosis patients. Five multiple sclerosis patients suffering from refractory recurrent trigeminal neuralgia involving all three trigeminal branches underwent deep brain stimulation of the posterior hypothalamus. The rationale of this intervention emerges from our earlier success in treating pain patients suffering from trigeminal autonomic cephalalgias. After follow-up periods that ranged from 1 to 4 years after treatment, the paroxysmal pain arising from the first trigeminal branch was controlled, whereas the recurrence of pain in the second and third trigeminal branches necessitated repeated thermorhizotomies to control in pain in two patients after 2 years of follow-up. In conclusion, deep brain stimulation may be considered as an adjunctive procedure for treating refractory paroxysmal pain within the first trigeminal division so as to avoid the complication of corneal reflex impairment that is known to follow ablative procedures.

Prevalence and impact of pain in multiple sclerosis: physical and psychologic contributors

OBJECTIVE

To characterize the prevalence and impact of pain in veterans with multiple sclerosis (MS) and to assess their association with demographic, biologic, and psychologic variables.

DESIGN

Cross-sectional cohort study linking computerized medical record information to mailed survey data.

SETTING

Veterans Health Administration (VHA).

PARTICIPANTS

Sixty-four percent (2994/4685) of veterans with MS who received services in VHA and also returned survey questionnaires.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Items assessing pain intensity, pain interference, and physical and mental health functioning.

RESULTS

Ninety-two percent of participants reported bodily pain within the prior 4 weeks, with 69% of the total sample indicating pain of moderate or higher intensity. Eighty-five percent indicated that pain caused functional interference during the past 4 weeks, with 71% of the total sample reporting pain-related interference that was moderate or greater. No significant sex or race differences emerged for the pain indices. A significant but modest relationship between increasing age and pain interference emerged (r=.05, P<.01); however, age was not significantly related to pain intensity. Multivariate regression analyses identified pain intensity (beta=.73), physical health functioning (beta=-.07), and mental health functioning (beta=-.13) variables as significant, unique contributors to the prediction of pain interference. The interaction of pain intensity and physical functioning was also significant but of minimal effect size (beta=-.03).

CONCLUSIONS

Pain is highly prevalent and causes substantial interference in the lives of veterans with MS. The functional impact of pain in veterans with MS is influenced by pain intensity, physical health, and emotional functioning. Clinical practice should take each of these domains into consideration and reflect a biopsychosocial conceptualization.

Central pain in multiple sclerosis - sensory abnormalities

Many patients with multiple sclerosis (MS) develop central neuropathic pain (CP). In the present study somatosensory abnormalities have been analysed in detail in 62 patients with MS and CP (42 women, 20 men; mean age 52 years) and in a control group of 10 women and 6 men (mean age 47 years) with MS and sensory symptoms, but without pain. Assessment included clinical testing and quantitative methods (QST) for the measurement of perception thresholds for touch, vibration, and temperatures. All CP patients except two (97%) had abnormal thresholds for innoxious and/or noxious temperatures, compared to 81% in the control group (p<0.05). There was a tendency towards the opposite regarding sensibility to touch, which was decreased in 66% vs. 87% (n.s.), vibration (55% vs. 81%; n.s.) and to joint movement (32% vs. 62%; p<0.04). Comparisons between painful and non-painful regions showed both the absolute threshold values and the index values to be significantly more abnormal, in the CP regions, for warmth (p<0.001), cold (p<0.05), difference limen (innoxious warmth and cold, p<0.01), cold pain (p<0.01) and heat pain/cold pain combined (p<0.001). Also the comparisons between regions with central pain and regions with sensory symptoms in the controls showed significantly more abnormal thresholds in the CP patients for warmth (p<0.05), cold (p<0.01), difference limen (innoxious warmth and cold, p<0.01) and heat pain/cold pain combined (p<0.001). The results support the general hypothesis that only patients who have lesions affecting the spinothalamo-cortical pathways run the risk of developing central pain.

A comparison of self-hypnosis versus progressive muscle relaxation in patients with multiple sclerosis and chronic pain

Twenty-two patients with multiple sclerosis (MS) and chronic pain we recruited into a quasi-experimental trial comparing the effects of self-hypnosis training (HYP) with progressive muscle relaxation (PMR) on pain intensity and pain interference; 8 received HYP and the remaining 14 participants were randomly assigned to receive either HYP or PMR. HYP-condition participants reported significantly greater pre- to postsession as well as pre- to posttreatment decreases in pain and pain interference than PMR-condition participants, and gains were maintained at 3-month follow-up. Most of the participants in both conditions reported that they continued to use the skills they learned in treatment and experienced pain relief when they did so. General hypnotizability was not significantly related to treatment outcome, but treatment-outcome expectancy assessed before and after the first session was. The results support the efficacy of self-hypnosis training for the management of chronic pain in persons with MS.