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

Methods to discriminate between nociceptive, neuropathic and nociplastic in children & adolescents: A systematic review of psychometric properties and feasibility

The aim of this systematic review was to identify and critically analyse the tools available for categorising pain as nociceptive, neuropathic and nociplastic pain in children and adolescents. Studies were included if they (i) included children and adolescents with a mean age of 0-24 years old, (ii) examined assessment tools that categorise pain as nociceptive, neuropathic or nociplastic, and (iii) examined the psychometric properties of the tools. Sensitive searches were conducted in five online databases in March 2024. Eligible studies were assessed for risk of bias and quality by two authors using COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) criteria. The search yielded 26 studies for 11 tools. No assessment tool had evidence for all nine recommended psychometric properties. Quantitative Sensory Testing, a tool used to identify signs and symptoms of nociplastic and neuropathic pain, was the most studied tool and had moderate evidence for construct validity, criterion validity and reliability. Three self-reported questionnaires, the Self-reported Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), Central Sensitisation Inventory (CSI) and PainDETECT, had moderate evidence for construct validity and show promise as preliminary tools to identify possible neuropathic or nociplastic pain. However, they had low specificity when used in isolation. All assessment methods would benefit from further psychometric evaluation and validation in children and adolescents. PERSPECTIVE: This systematic review highlights the limited validation of pain assessment tools for children and adolescents. While Quantitative Sensory Testing and self-reported questionnaires show promise in identifying pain mechanisms, their applicability remains uncertain. Further psychometric validation is crucial to improve pain assessment and guide personalized treatment in young populations.

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.

Spasticity-Plus syndrome in multiple sclerosis patients in a tertiary hospital in Spain

Introduction

Spasticity is a common symptom in multiple sclerosis (MS) and it is often associated with other symptoms such as spasms/cramps and pain. The concept of Spasticity-Plus syndrome takes into account that spasticity is accompanied by one or more symptoms (spasms/cramps, pain, bladder dysfunction, sleep disorders, fatigue and/or tremor). As these symptoms share a common cannabinoid control, therapy acting on cannabinoid receptors may be useful. The main study objectives were to determine the number of MS patients who met Spasticity-Plus syndrome criteria and to identify the most common symptoms.

Methods

Clinical records of MS patients treated with nabiximols in a tertiary hospital from 2002 to 2022 were reviewed retrospectively.

Results

Of the 73 patients included in the study, 53.4% were women, and most had secondary progressive MS (64.4%). All patients met the criteria for Spasticity-Plus syndrome: 100% had spasticity and at least another symptom. Pain was the second most common symptom (91.8%), followed by spasms/cramps (79.4%), and fatigue (76.7%). Sleep disturbances (p < 0.0001) and tremor (p < 0.027) were more frequent in patients with relapsing-remitting MS than in patients with progressive MS. No statistically significant differences were found for spasticity, pain, spasms/cramps, and fatigue between MS phenotypes. Regarding symptoms clusters, 94.4% of the patients had three or more symptoms. Spasticity was more frequently associated with pain (91.8%) and spasms/cramps (79.4%).

Conclusion

Spasticity-Plus syndrome was present in all the study population of patients with different MS phenotypes, and treated with nabiximols.

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.

Widespread Pain With Nociplastic Features is an Independent Predictor of Low Physical Activity in People with Multiple Sclerosis

Exploring the relationship between underlying pain mechanisms and physical activity could inform interventions to optimize physical activity in persons with multiple sclerosis (PwMS). This cross-sectional nationwide survey examined whether pain phenotype is a significant predictor of self-reported physical activity in PwMS. The study included 938 persons with a self-reported diagnosis of MS (93% reported neurologist-diagnosed MS) who completed surveys of demographic, clinical information, pain intensity, indicators of underlying pain mechanisms (Fibromyalgia Survey Criteria and painDETECT), and physical activity (Godin Leisure-Time Exercise Questionnaire). Responses were used to categorize pain phenotypes as widespread pain with nociplastic features (WPNF), neuropathic, nociceptive, or mixed (neuropathic/WPNF). Following current physical activity guidelines, self-reported physical activity was categorized as active or insufficiently active/sedentary. Applying multivariable logistic regression, participants with no chronic pain had 2.30 higher odds of being physically active when compared to participants with chronic mixed pain. Similarly, participants with neuropathic and nociceptive pain had, respectively, 1.90 and 1.66 higher odds of being physically active compared to individuals with mixed pain. Higher scores on the fibromyalgia survey criteria (operationalized in this study as an indicator of WPNF) were a significant independent predictor of insufficient physical activity (OR = .93, P < .01). Findings indicate that experience and phenotype of chronic pain, in particular WPNF, are associated with physical inactivity in PwMS. This suggests that assessing pain phenotype may be important to identify individuals at risk of inadequate physical activity and may guide the tailoring of behavioral therapeutic approaches to help PwMS achieve the recommended level of physical activity. PERSPECTIVE: This study examines the association between pain mechanism and physical activity in multiple sclerosis. These findings highlight the possibility that a basic screening for pain mechanism could offer clinically useful information without requiring extensive neurobiological phenotyping and may inform the development of behavioral interventions to enhance physical activity in multiple sclerosis.

Feasibility of Low-Load Resistance Training Using Blood Flow Restriction for People With Advanced Multiple Sclerosis: A Prospective Cohort Study

OBJECTIVE

The objective of this study was to determine the feasibility of low-load resistance training with blood flow restriction (BFR) for people with advanced disability due to multiple sclerosis (MS).

METHODS

In this prospective cohort study, 14 participants with MS (Expanded Disability Status Scale [EDSS] score = 6.0 to 7.0; mean age = 55.4 [SD = 6.2] years; 71% women) were asked to perform 3 lower extremity resistance exercises (leg press, calf press, and hip abduction) bilaterally twice weekly for 8 weeks using BFR. Feasibility criteria were as follows: enrollment of 20 participants, ≥80% retention and adherence, ≥90% satisfaction, and no serious adverse events related to the intervention. Other outcomes included knee extensor, ankle plantar flexor, and hip abductor muscle strength, 30-Second Sit-to-Stand Test, Berg Balance Scale, Timed 25-Foot Walk Test, 12-Item MS Walking Scale, Modified Fatigue Impact Scale, Patient-Specific Functional Scale, and daily step count.

RESULTS

Sixteen participants consented, and 14 completed the intervention, with 93% adherence overall. All participants were satisfied with the intervention. A minor hip muscle strain was the only intervention-related adverse event. There were muscle strength improvements on the more-involved (16%-28%) and less-involved (12%-19%) sides. There were also changes in the 30-Second Sit-to-Stand Test (1.9 repetitions; 95% CI = 1.0 to 2.8), Berg Balance Scale (5.3 points; 95% CI = 3.2 to 7.4), Timed 25-Foot Walk Test (-3.3 seconds; 95% CI = -7.9 to 1.3), Modified Fatigue Impact Scale (-8.8 points; 95% CI = -16.5 to -1.1), 12-Item MS Walking Scale (-3.6 points; 95% CI = -11.5 to 4.4), Patient-Specific Functional Scale (2.9 points; 95% CI = 1.9 to 3.8), and daily step count (333 steps; 95% CI = -191 to 857).

CONCLUSION

Low-load resistance training using BFR in people with MS and EDSS scores of 6.0 to 7.0 appears feasible, and subsequent investigation into its efficacy is warranted.

IMPACT

Although efficacy data are needed, combining BFR with low-load resistance training may be a viable alternative for people who have MS and who do not tolerate conventional moderate- to high-intensity training because of more severe symptoms, such as fatigue and weakness.

LAY SUMMARY

Low-load strength training with BFR was feasible in people who have advanced disability due to MS. Using BFR may provide an alternative for people with MS who do not tolerate higher intensity training due to more severe symptoms, such as fatigue and weakness.

Feasibility interventional study investigating PAIN in neurorehabilitation through wearabLE SensorS (PAINLESS): a study protocol

INTRODUCTION

Millions of people survive injuries to the central or peripheral nervous system for which neurorehabilitation is required. In addition to the physical and cognitive impairments, many neurorehabilitation patients experience pain, often not widely recognised and inadequately treated. This is particularly true for multiple sclerosis (MS) patients, for whom pain is one of the most common symptoms. In clinical practice, pain assessment is usually conducted based on a subjective estimate. This approach can lead to inaccurate evaluations due to the influence of numerous factors, including emotional or cognitive aspects. To date, no objective and simple to use clinical methods allow objective quantification of pain and the diagnostic differentiation between the two main types of pain (nociceptive vs neuropathic). Wearable technologies and artificial intelligence (AI) have the potential to bridge this gap by continuously monitoring patients' health parameters and extracting meaningful information from them. Therefore, we propose to develop a new automatic AI-powered tool to assess pain and its characteristics during neurorehabilitation treatments using physiological signals collected by wearable sensors.

METHODS AND ANALYSIS

We aim to recruit 15 participants suffering from MS undergoing physiotherapy treatment. During the study, participants will wear a wristband for three consecutive days and be monitored before and after their physiotherapy sessions. Measurement of traditionally used pain assessment questionnaires and scales (ie, painDETECT, Doleur Neuropathique 4 Questions, EuroQoL-5-dimension-3-level) and physiological signals (photoplethysmography, electrodermal activity, skin temperature, accelerometer data) will be collected. Relevant parameters from physiological signals will be identified, and AI algorithms will be used to develop automatic classification methods.

ETHICS AND DISSEMINATION

The study has been approved by the local Ethical Committee (285-2022-SPER-AUSLBO). Participants are required to provide written informed consent. The results will be disseminated through contributions to international conferences and scientific journals, and they will also be included in a doctoral dissertation.

TRIAL REGISTRATION NUMBER

NCT05747040.

Fatigue, pain interference, and psychiatric morbidity in multiple sclerosis: The role of childhood stress

BACKGROUND

Multiple sclerosis (MS) is a progressive, autoimmune disease of the central nervous system that affects nearly one million Americans. Despite the existence of immunomodulatory therapies to slow physical and cognitive disability progression, interventions to ameliorate common symptoms of MS, including fatigue and pain, remain limited. Poor understanding of risk factors for these symptoms may contribute to treatment challenges. In recent years, childhood stress has been investigated as a risk factor for chronic autoimmune conditions including MS; yet remarkably few studies have investigated the relationship between childhood stressors and chronic MS symptoms. Our aim was to examine clusters of stressors and three key features of MS: fatigue, pain interference, and psychiatric morbidity.

METHODS

Cross-sectional data were collected from a sample of People with MS (PwMS) via a national web-based survey that assessed the presence and type of childhood stressors and MS clinical features. Hierarchical block regression was used to assess associations among emotional, physical, and environmental childhood stressors and three clinical features commonly experienced by PwMS.

RESULTS

N = 719 adults with MS (aged 21-85) completed the survey. Childhood emotional and physical stressors were significantly associated with overall presence of fatigue (p = 0.02; p<0.03) and pain interference (p<0.001; p<0.001) in adulthood, as well as the magnitude of both outcomes. Environmental stressors (p<0.001), in addition to emotional (p<0.001) and physical (p<0.001) stressors were significantly associated with psychiatric morbidity in PwMS.

CONCLUSION

Childhood stress may predict fatigue, psychiatric morbidity, and pain in adults with MS. Further research is needed to show cause and effect; however, if an association exists, strategies to mitigate the impact of childhood stress could offer new pathways to reduce the severity of these symptoms. Broadly, this work adds to the body of evidence supporting upstream preventive measures to help address the stress on children and families.

Characterizing cannabis use in a sample of adults with multiple sclerosis and chronic pain: An observational study

BACKGROUND

Although cannabis has become an increasingly common method for pain management among people with multiple sclerosis (PwMS), there is a dearth of knowledge regarding the types of cannabis products used as well as the characteristics of cannabis users. The current study aimed to (1) describe the prevalence of cannabis use and the routes of administration of cannabis products in adults with an existing chronic pain condition and MS, (2) to examine differences in demographic and disease-related variables between cannabis users and non-users, and (3) to examine differences between cannabis users and non-users in pain-related variables, including pain intensity, pain interference, neuropathic pain, pain medication use, and pain-related coping.

METHODS

Secondary analysis of baseline data from participants with multiple sclerosis (MS) and chronic pain (N = 242) enrolled in an RCT comparing mindfulness-based cognitive therapy (MBCT), cognitive-behavioral therapy (CBT), and usual care for chronic pain. Statistical methods included t-tests, Mann-Whitney tests, chi-square tests, and Fisher's exact tests to assess for differences in demographic, disease-related, and pain-related variables between cannabis users and non-users.

RESULTS

Of the 242 participants included in the sample, 65 (27%) reported the use of cannabis for pain management. The most common route of administration was oil/tincture (reported by 42% of cannabis users), followed by vaped (22%) and edible (17%) products. Cannabis users were slightly younger than non-users (Medage 51.0 vs 55.0, p = .019) and reported higher median pain intensity scores (6.0 vs 5.0, p = .022), higher median pain interference scores (5.9 vs 5.4, p = .027), and higher median levels of neuropathic pain (20.0 vs 16.0, p = .001).

CONCLUSIONS

The current study identified factors that may intersect with cannabis use for pain management and adds to our current knowledge of the types of cannabis products used by PwMS. Future research should continue to investigate trends in cannabis use for pain management, especially as the legality and availability of products continue to shift. Additionally, longitudinal studies are needed to examine the effects of cannabis use on pain-related outcomes over time.

What Do We Know about Nociplastic Pain?

Nociplastic pain is a recently distinguished type of pain, distinct from neuropathic and nociceptive pain, and is well described in the literature. It is often mistaken for central sensitization. Pathophysiology has not been clearly established with regard to alteration of the concentration of spinal fluid elements, the structure of the white and gray matter of the brain, and psychological aspects. Many different diagnostic tools, i.e., the painDETECT and Douleur Neuropathique 4 questionnaires, have been developed to diagnose neuropathic pain, but they can also be applied for nociplastic pain; however, more standardized instruments are still needed in order to assess its occurrence and clinical presentation. Numerous studies have shown that nociplastic pain is present in many different diseases such as fibromyalgia, complex regional pain syndrome type 1, and irritable bowel syndrome. Current pharmacological and nonpharmacological treatments for nociceptive and neuropathic pain are not entirely suitable for treating nociplastic pain. There is an ongoing effort to establish the most efficient way to manage it. The significance of this field has led to several clinical trials being carried out in a short time. The aim of this narrative review was to discuss the currently available evidence on pathophysiology, associated diseases, treatment possibilities, and clinical trials. It is important that physicians widely discuss and acknowledge this relatively new concept in order to provide optimized pain control for patients.

Microbiological and Physiological Effects of Pain

Pain is an important innate defense mechanism that can dramatically alter a person's quality of life. Understanding the microbiological and physiological effects of pain may be important in the pursuit of novel pain interventions. The three descriptors of pain recognized by the International Association for the Study of Pain are nociceptive, neuropathic, and nociplastic pain. Our review examined the current understanding of all three pain types, focusing on the key molecules involved in the manifestation of each type as well as physiological effects. Additionally, we compared the differences in painful and painless neuropathies and discussed the neuroimmune interaction involved in the manifestation of pain.

Pain in patients with multiple sclerosis

Objectives

This study aims to identify the factors associated with pain and neuropathic pain (NP) in patients with multiple sclerosis (MS) and to determine the relationship between pain and NP with disability, functionality, activities of daily living, fatigue, mood, and quality of life (QoL).

Patients and methods

Between July 2017 and October 2017, a total of 100 adult patients with MS (18 males, 82 females; mean age: 35.3±9.9 years; range, 19 to 71 years) were included. All patients were evaluated in terms of pain and NP. Patients with and without pain, and patients with and without NP were compared in terms of sociodemographic characteristics, disease data, disability, functionality, daily living activities, fatigue severity, mood, and QoL using various scales.

Results

A total of 62% of the patients had pain. Pain was found to be associated with low education level (p=0.014), increased fatigue (p<0.001), depressive mood (p<0.001) and lower QoL (p<0.001). A total of 29.03% of patients with pain had NP. Patients with NP had a greater pain intensity (p<0.001) and fatigue (p=0.002) and lower QoL (p=0.011). The number of patients who received the correct treatment for their symptoms was low.

Conclusion

Pain and NP should be better investigated and treated by physicians, as these symptoms are common in MS and adversely affect the QoL and social relations of affected patients and reduce their productivity.

Characterizing mechanism-based pain phenotypes in patients with chronic pancreatitis: a cross-sectional analysis of the PROspective Evaluation of Chronic Pancreatitis for EpidEmiologic and Translational StuDies

ABSTRACT

Pain is common in chronic pancreatitis (CP) and profoundly reduces quality of life (QoL). Multiple underlying mechanisms contribute to a heterogenous pain experience and reduce efficacy of pain management. This study was designed to characterize the distribution of mechanism-based pain phenotypes in painful CP. The data analyzed were collected as part of the PROspective Evaluation of Chronic Pancreatitis for EpidEmiologic and Translational StuDies, an NCI/NIDDK-funded longitudinal study of the natural history of CP. The PROspective Evaluation of Chronic pancreatitis for EpidEmiologic and translational stuDies includes patient-reported outcome (PRO) measures of pain, medication use, global health, and QoL. Of subjects (N = 681) with CP, 80% experienced abdominal pain within the year before enrollment. Subjects who experienced pain in the week before enrollment (N = 391) completed PROMIS Neuropathic and Nociceptive Pain Quality instruments which were then used to classify them by pain type: 40% had nociceptive, 5% had neuropathic-like, and 32% had both types of pain. The prevalence of having both types of pain was higher among women and subjects with diabetes mellitus, whereas nociceptive-only pain was more prevalent among men and those with pancreatic duct stricture. Other factors, including pain medication use and healthcare utilization, did not differ between groups based on pain type. Subjects in the Both group had significantly worse health and QoL scores relative to those with nociceptive-only pain, suggesting that using psychosocial pain surveys may be useful for understanding pain subtypes in patients with CP. Additional research is needed to identify biochemical and biophysical signatures that may associate with and predict responses to mechanism-specific interventions.

Subtypes of relapsing-remitting multiple sclerosis identified by network analysis

We used network analysis to identify subtypes of relapsing-remitting multiple sclerosis subjects based on their cumulative signs and symptoms. The electronic medical records of 113 subjects with relapsing-remitting multiple sclerosis were reviewed, signs and symptoms were mapped to classes in a neuro-ontology, and classes were collapsed into sixteen superclasses by subsumption. After normalization and vectorization of the data, bipartite (subject-feature) and unipartite (subject-subject) network graphs were created using NetworkX and visualized in Gephi. Degree and weighted degree were calculated for each node. Graphs were partitioned into communities using the modularity score. Feature maps visualized differences in features by community. Network analysis of the unipartite graph yielded a higher modularity score (0.49) than the bipartite graph (0.25). The bipartite network was partitioned into five communities which were named fatigue, behavioral, hypertonia/weakness, abnormal gait/sphincter, and sensory, based on feature characteristics. The unipartite network was partitioned into five communities which were named fatigue, pain, cognitive, sensory, and gait/weakness/hypertonia based on features. Although we did not identify pure subtypes (e.g., pure motor, pure sensory, etc.) in this cohort of multiple sclerosis subjects, we demonstrated that network analysis could partition these subjects into different subtype communities. Larger datasets and additional partitioning algorithms are needed to confirm these findings and elucidate their significance. This study contributes to the literature investigating subtypes of multiple sclerosis by combining feature reduction by subsumption with network analysis.

Lower corticospinal excitability and greater fatigue among people with multiple sclerosis experiencing pain

Introduction

Persons with multiple sclerosis (MS) frequently report pain that negatively affects their quality of life. Evidence linking pain and corticospinal excitability in MS is sparse. We aimed to (1) examine differences in corticospinal excitability in MS participants with and without pain and (2) explore predictors of pain.

Methods

Sixty-four participants rated their pain severity on a visual analog scale (VAS). Transcranial magnetic stimulation (TMS) and validated clinical instruments characterized corticospinal excitability and subjective disease features like mood and fatigue. We retrieved information on participants' prescriptions and disability status from their clinical records.

Results

Fifty-five percent of participants reported pain that affected their daily functioning. Persons with pain had significantly greater fatigue and lower area under the excitatory motor evoked potential (MEP) recruitment curve (eREC AUC), a measure of total corticospinal excitability. After controlling for age, disability status, and pain medications, increased fatigue and decreased eREC AUC together explained 40% of the variance in pain.

Discussion

Pain in MS is multifactorial and relates to both greater fatigue and lesser corticospinal excitability. Future work should better characterize relationships between these outcomes to develop targeted pain interventions such as neuromodulation.

Summary

We examined pain in MS. Individuals with pain had higher fatigue and lower corticospinal excitability than those without pain. These outcomes significantly predicted self-reported pain.

Nociplastic Pain in Multiple Sclerosis Spasticity: Dermatomal Evaluation, Treatment with Intradermal Saline Injection and Outcomes Assessed by 3D Gait Analysis: Review and a Case Report

Nociplastic pain has been introduced by the IASP as a third category of pain, distinct from nociceptive and neuropathic pain. Pathogenetically, it is considered to be a continuum of these two types of pain after becoming chronic. Repetitive peripheral painful stimulation causes a central sensitization with hypersensitivity of the corresponding spinal metamer or brain region. Therefore, signs of altered nociception, such as allodynia, may be found on the tissues of the related dermatome, myotome and sclerotome, and characterize nociplastic pain. This kind of pain was found in over 20% of people with multiple sclerosis (pwMS), a demyelinating autoimmune disease that affects the central nervous system. Nociplastic pain may be an amplifier of spasticity, the main pyramidal symptom that affects about 80% of pwMS. This article details the case of a 36-year-old woman with multiple sclerosis who was affected by spasticity and non-specific pain of the lower limbs, disabling on walking. Previous analgesic and muscle relaxant treatment had no benefits. The diagnosis of nociplastic pain on the cutaneous tissue of the anterolateral region of the left thigh and its treatment with intradermal normal saline injection on the painful skin area showed immediate and lasting effects on pain and spasticity, improving significantly the patient’s balance and walking, as assessed by a 3D motion analysis and rating scales.

Inverse Association Between Persistence With Antidepressant Medication and Onset of Chronic Pain in Patients With Depression: A Retrospective Cohort Study

PURPOSE/BACKGROUND

Despite the known involvement of depression in chronic pain, the association between persistence with and adherence to antidepressant medication and onset of chronic pain in patients with depression remains unclear.

METHODS/PROCEDURES

This retrospective cohort study used a Japanese claims database to extract data for adult patients with depression who were prescribed antidepressants between April 2014 and March 2020. Patients were divided into groups according to duration of continuous prescription of antidepressants (≥6 months [persistent group] and <6 months [nonpersistent group]) and medication possession ratio (≥80% [good adherence group] and <80% [poor adherence group]). The outcome was onset of chronic pain, which was defined as continuous prescription >3 months of analgesics and diagnosis of pain-related condition after discontinuation of the first continuous antidepressant prescription. The risk of onset of chronic pain was compared between the paired groups.

FINDINGS/RESULTS

A total of 1859 patients were selected as the study population and categorized as the persistent (n = 406) and nonpersistent (n = 1453) groups, and good adherence (n = 1551) and poor adherence (n = 308) groups. Risk of onset of chronic pain was significantly lower in the persistent group than in the nonpersistent group after controlling for confounding via standardized mortality ratio weighting (hazard ratio, 0.38; 95% confidence interval, 0.18-0.80; P = 0.011). There was no significant difference between the good and poor adherence groups.

IMPLICATIONS/CONCLUSIONS

Antidepressant persistence for ≥6 months is recommended and may reduce the onset of chronic pain in patients with depression.

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.

Physical and Mental Health Comorbidities Among Adults With Multiple Sclerosis

OBJECTIVE

To compare the incidence of and adjusted hazard ratios for common cardiometabolic diseases, musculoskeletal disorders, and psychological morbidities among adults with and without multiple sclerosis (MS).

PATIENTS AND METHODS

Beneficiaries were included if they had an International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic code for MS (n=9815) from a national private insurance claims database (Clinformatics Data Mart; OptumInsight). Adults without MS were also included (n=1,474,232) as a control group. Incidence estimates of common cardiometabolic diseases, musculoskeletal disorders, and psychological morbidities were compared at 5 years of continuous enrollment. Survival models were used to quantify unadjusted and adjusted hazard ratios for incident morbidities.

RESULTS

Adults with MS had a higher incidence of any common cardiometabolic disease (51.6% [2663 of 5164] vs 36.4% [328,690 of 904,227]), musculoskeletal disorder (68.8% [3411 of 4959] vs 47.5% [512,422 of 1,077,737]), and psychological morbidity (49.4% [3305 of 6691] vs 30.8% [380,893 of 1,235,388]) than adults without MS, and differences were clinically meaningful (all P<.001). Fully adjusted survival models revealed that adults with MS had a greater risk for any (hazard ratio [HR], 1.37; 95% CI, 1.32 to 1.43) and all (HR, 1.19 to 1.48) common cardiometabolic diseases, any (HR, 1.59; 95% CI, 1.53 to 1.64) and all (HR, 1.22 to 2.77) musculoskeletal disorders, and any (HR, 1.57; 95% CI, 1.51 to 1.62) and all (HR, 1.20 to 2.51) but one (impulse control disorders) psychological morbidity.

CONCLUSION

Adults with MS have a significantly higher risk for development of common cardiometabolic diseases, musculoskeletal disorders, and psychological morbidities (all P<.001) than adults without MS. Efforts are needed to facilitate the development of improved clinical screening algorithms and early interventions to reduce risk of chronic physical and mental disease onset/progression in this higher risk population.

Pain Phenotypes in Adults Living With Cerebral Palsy

Background and Objectives

To identify pain phenotypes among adults living with cerebral palsy (CP) and compare phenotypes of pain intensity, anxiety and depressive symptoms, and self-reported perceived stress.

Methods

Seventy-one adults with CP presented to the University of Michigan (mean age = 39.3 ± 16.2; 43 women, 28 men). The median of 6 on the American College of Rheumatology fibromyalgia survey was used to classify patients for nociplastic pain centralization. The painDETECT Score was used to classify patients for neuropathic pain. These measures were then used to cross-classify each patient into 1 of 4 possible pain categories: neuropathic, nociplastic, mixed neuropathic/noclipastic, or nociceptive pain (-neuropathic/-nociplastic pain).

Results

Twenty-eight adults with CP (39.4%) were classified as nociceptive, 24 (33.8%) as nociplastic, 8 (11.3%) as neuropathic, and 11 (15.5%) as mixed neuropathic/nociplastic. Subgroups differed significantly on average scores on the Brief Pain Inventory pain intensity scale, the Perceived Stress Scale, and on the Patient-Reported Outcomes Measurement Information System measures of anxiety and depression; the nociceptive pain subgroup reported lower pain and emotional distress compared with the other groups.

Discussion

Findings suggest that type of pain is variable among adults with CP and may arise through multiple mechanisms.

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.