Pain and pain mechanisms in patients with inflammatory arthritis: A Danish nationwide cross-sectional DANBIO registry survey

"Inflammatory or non-inflammatory pain in inflammatory arthritis - How to differentiate it?"

Pain is a significant issue in rheumatoid arthritis (RA) and psoriatic arthritis (PSA) and can have a negative impact on patients' quality of life. Despite optimal control of inflammatory disease, residual chronic pain remains a major unmet medical need in RA. Pain in RA can be secondary to inflammation but can also generate neuroendocrine responses that initiate neurogenic inflammation and enhance cytokine release, leading to persistent hyperalgesia. In addition to well-known cytokines such as TNFα and IL-6, other cytokines and the JAK-STAT pathway play a role in pain modulation and inflammation. The development of chronic pain in RA involves processes beyond inflammation or structural damage. Residual pain is often observed in patients even after achieving remission or low disease activity, suggesting the involvement of non-inflammatory and central sensitization mechanisms. Moreover, fibromyalgia syndrome (FMS) is prevalent in RA patients and may contribute to persistent pain. Factors such as depression, sleep disturbance, and pro-inflammatory cytokines may contribute to the development of fibromyalgia in RA. It is essential to identify and diagnose concomitant FMS in RA patients to better manage their symptoms. Further research is needed to unravel the complexities of pain in RA. Finally, recent studies have shown that JAK inhibitors effectively reduce residual pain in RA patients, suggesting pain-reducing effects independent of their anti-inflammatory properties.

A randomised controlled trial of the effect of intra-articular lidocaine on pain scores in inflammatory arthritis

ABSTRACT

Chronic pain in inflammatory arthritis (IA) reflects a complex interplay between active disease in a peripheral joint and central pronociceptive mechanisms. Because intra-articular lidocaine may be used to abolish joint-specific peripheral input to the central nervous system, we aimed to validate its use as a clinical tool to identify those patients with IA whose pain likely incorporates centrally mediated mechanisms. We began by investigating whether there was a placebo response of intra-articular injection in patients with IA 1:1 randomised to receive intra-articular lidocaine or control (0.9% saline). After, in a larger patient cohort not randomized to placebo vs lidocaine groups, we tested whether patients with IA could be stratified into 2 cohorts based on their response to intra-articular lidocaine according to markers of centrally mediated pain. To this end, we evaluated postlidocaine pain numerical rating scale (NRS) scores alongside baseline painDETECT, fibromyalgia criteria fulfillment, and quantitative sensory testing outcomes. Numerical rating scale scores were collected at baseline and 3-, 5-, and 10-minutes postinjection. Firstly, the placebo effect of intra-articular injection was low: compared to baseline, the mean pain NRS score 5-minutes postinjection was reduced by 3.5 points in the lidocaine group vs 1.2 points in the control group. Secondly, postlidocaine NRS scores were significantly higher in those with a high (>18) baseline painDETECT score, fibromyalgia, and low-pressure pain threshold at the trapezius (P = 0.002, P = 0.001, P = 0.005, respectively). Persistent high pain after intra-articular lidocaine injection could be used as an indicator of pronociceptive mechanisms that are centrally mediated, informing centrally targeted analgesic strategies.

The Burden of Work Productivity and Activity Impairment in Patients with Psoriasis, Psoriatic Arthritis, Ulcerative Colitis, and Crohn's Disease

BACKGROUND

Comparisons among autoimmune diseases enable understanding of the burden and factors associated with work productivity loss and impairment.

AIMS

The objective was to compare work productivity and activity and associated factors among patients with inflammatory bowel diseases and other autoimmune conditions.

METHODS

This cross-sectional study included employed, adult patients (age 20-64 years) in the CorEvitas Inflammatory Bowel Disease, Psoriasis, and Psoriatic Arthritis/Spondyloarthritis Registries between 5/2017 and 6/2020. Any patient-reported impairment on four domains of the Work Productivity and Activity Index (WPAI) was collected across registries. Prevalence for each autoimmune disease was reported and stratified by disease activity using direct age-sex-standardization. Factors associated with the presence of any WPAI were identified in logistic regression models.

RESULTS

A total of 7,169 patients with psoriasis (n = 4,768, 67%), psoriatic arthritis (n = 1,208, 17%), Crohn's disease (CD, n = 621, 9%), and ulcerative colitis (UC, n = 572, 8%) met inclusion criteria. Among patients not in remission across all disease cohorts, the age-sex-standardized prevalence of any presenteeism, work productivity loss, and activity impairment ranged from 54 to 97%. Patients with CD in remission had higher standardized prevalence of presenteeism (53% [48-57%]) and work productivity loss (54% [49-59%]), compared to those from other cohorts (presenteeism [range: 33-39%] and work productivity loss [range: 37-41%]). For all WPAI domains, the strongest adjusted associations were for moderate to severe disease activity and psychosocial symptoms.

CONCLUSIONS

Patients with moderate to severe disease activity reported the highest WPAI burden. However, patients in remission or mild disease activity also report some WPAI burden, emphasizing a multidisciplinary treatment approach to improve work productivity loss and impairment.

Exploring the effect on primary endpoints in trials testing targeted therapy interventions for rheumatoid arthritis: a meta-epidemiological study on the appropriate use of a core outcome set

OBJECTIVES

To explore which core domain is best associated with the American College of Rheumatology (ACR) 20% response in trials assessing the effect of targeted interventions in rheumatoid arthritis (RA).

METHODS

A meta-epidemiological study was performed on randomised trials investigating biologics and targeted agents compared with placebo or conventional disease-modifying antirheumatic drugs in patients with RA. The main outcome measures were ORs for the ACR 20% response and at least one of the eight core domains according to the existing RA core outcome set (COS) analysed based on standardised mean differences.

RESULTS

115 trials involving 55 422 patients with RA were eligible. The OR for achieving ACR 20% response was 3.19 (95% CI 2.96 to 3.44) for the experimental interventions relative to the comparators. The median number of COS domains reported was 6; 18 trials reported only 1 domain, 17 all 8. Univariable meta-regression analyses indicated that each of the eight core domains was significantly associated with ACR 20% response, yet improvements in physical disability explain a successful ACR 20% response the most. Including only trials reporting on all eight core domains, univariable meta-regression analyses proved improvement in fatigue to explain a successful ACR 20% response the most.

CONCLUSIONS

Within this dataset, it is evident that the conclusions concerning our primary objective were significantly influenced by both the amount and characteristics of missing data. Our data suggest that fatigue could be more important for the primary endpoint than previously assumed, but this is based on limited data.

Pain sensitisation and joint inflammation in patients with active rheumatoid arthritis

INTRODUCTION

Despite better therapies and strategies, many people with rheumatoid arthritis (RA) have persistent pain, often from abnormal pain processing, now termed nociplastic pain. However, RA patients with fibromyalgia (FM), a central nociplastic pain syndrome, also have power doppler ultrasound (PDUS+) joint inflammation. To understand the complex causes of pain, we performed clinical examination and patient-reported outcome measures (PROMs) plus comprehensive PDUS evaluation not previously combined.

METHODS

In a cross-sectional study of sequential RA patients with at least moderate DAS28 erythrocyte sedimentation rate disease activity, we assessed 66/68 joints for swelling and tenderness, respectively, FM American College of Rheumatology 2010 diagnostic criteria, completed PROMs for function, quality of life and mood, alongside PDUS examination of 44 joints. Statistical analysis included logistic regression modelling and regularised (lasso) logistic regression methods.

RESULTS

From 158 patients, 72 (46%) patients met FM criteria, with significantly worse tender joint counts and PROMs, but no differences in PDUS compared with the non-FM group. Categorising patients by PDUS+ joint presence and/or FM criteria, we identified four distinct groups: 43 (27.2%) patients with -FM-PD, 43 (27.2%) with -FM+PD, 42 (26.6%) with +FM-PD and 30 (19%) with +FM+PD. Both FM+ groups had worse PROMs for fatigue, mood and pain, compared with the FM- groups. We were unable to develop algorithms to identify different groups.

CONCLUSION

The unexpected group -FM-PD group may have peripheral nociplastic pain, not commonly recognised in rheumatology. Only 46% of patients demonstrated PDUS+ inflammation. However clinical examination and PROMs did not reliably differentiate groups, emphasising PDUS remains an important tool.

Persistent pain and its predictors after starting anti-tumour necrosis factor therapy in psoriatic arthritis: what is the role of inflammation control?

OBJECTIVE

While considerable focus has been placed on pain due to inflammation in psoriatic arthritis (PsA), less is reported on pain despite inflammation control. Here, we aimed to investigate the occurrence/predictors of persistent pain, including non-inflammatory components, after starting anti-tumour necrosis factor (anti-TNF) therapy.

METHOD

Bionaïve PsA patients starting a first anti-TNF therapy 2004-2010 were identified (South Swedish Arthritis Treatment Group register; N = 351). Outcomes included unacceptable pain [visual analogue scale (VAS) pain > 40 mm], and unacceptable pain despite inflammation control (refractory pain; VAS pain > 40 mm + C-reactive protein < 10 mg/L + ≤ 1 swollen joint of 28), assessed at 0, 3, 6, and 12 months. Baseline predictors were estimated by logistic regression.

RESULTS

Upon starting anti-TNF therapy, 85% of patients reported unacceptable pain, falling to 43% at 3 months and then remaining stable. After 12 months, refractory pain constituted 63% of all unacceptable pain. Higher baseline VAS pain/global, worse physical function and lower health-related quality-of-life were associated with a higher risk of unacceptable/refractory pain at 12 months. More swollen joints and higher evaluator's global assessment were associated with a lower risk of 12-month refractory pain.

CONCLUSIONS

A substantial proportion of PsA patients reported unacceptable pain throughout the first anti-TNF treatment year. At 12 months, refractory pain constituted about two-thirds of this remaining pain load. More objective signs of inflammation at anti-TNF initiation were associated with less future refractory pain. This highlights insufficient effect of biologics in patients with inflammation-independent pain, warranting alternative treatments.

The role of specialized pro-resolving mediators (SPMs) in inflammatory arthritis: A therapeutic strategy

Rheumatoid arthritis (RA) is classified as a persistent inflammatory autoimmune disorder leading to the subsequent erosion of articular cartilage and bone tissue originating from the synovium. The fundamental objective of therapeutic interventions in RA has been the suppression of inflammation. Nevertheless, conventional medicines that lack target specificity may exhibit unpredictable effects on cell metabolism. In recent times, there has been evidence suggesting that specialized pro-resolving mediators (SPMs), which are lipid metabolites, have a role in facilitating the resolution of inflammation and the reestablishment of tissue homeostasis. SPMs are synthesized by immune cells through the enzymatic conversion of omega-3 fatty acids. In the context of RA, there is a possibility of dysregulation in the production of these SPMs. In this review, we delve into the present comprehension of the endogenous functions of SPMs in RA as lipids that exhibit pro-resolutive, protective, and immunoresolvent properties.

Central Sensitization in Psoriatic Arthritis: Relationship With Composite Measures of Disease Activity, Functional Disability, and Health-Related Quality of Life

OBJECTIVE

To investigate the prevalence of central sensitization (CS) in patients with psoriatic arthritis (PsA) and its association with disease activity and patient-reported outcome measures.

METHODS

This cross-sectional study included adults with PsA without coexisting fibromyalgia (FM). Patients underwent a clinimetric assessment to collect variables regarding disease activity, quality of life (QOL), functional ability, impact of disease, and CS. Spearman ρ was used to examine the relationship between CS Inventory (CSI) scores and other variables. A multivariate analysis was performed to determine the independent contribution of each variable to the 12-item Psoriatic Arthritis Impact of Disease (PsAID-12) score.

RESULTS

One hundred fifty-seven patients were enrolled. Of them, 45.2% scored a CSI ≥ 40, indicating a high probability of CS. Significant correlations were found between CSI and disease activity, as evaluated by Disease Activity in Psoriatic Arthritis score and Psoriatic Arthritis Disease Activity Score (ρ 0.587 and ρ 0.573, respectively), between CSI and the Health Assessment Questionnaire (ρ 0.607), and between CSI and the 36-item Short Form Health Survey physical component summary and mental component summary scores (ρ -0.405 and ρ -0.483, respectively). In multivariate analysis, CSI score was the principal independent variable (P < 0.001) contributing to PsAID-12 score.

CONCLUSION

Patients with PsA with symptoms of CS had higher disease activity, worse functional ability, and worse QOL. The presence of CS is the major contributor in the impact of disease.

Quantitative sensory testing, psychological profiles and clinical pain in patients with psoriatic arthritis and hand osteoarthritis experiencing pain of at least moderate intensity

BACKGROUND

Chronic pain is the hallmark symptom of joint diseases. This study examined the differences in quantitative sensory testing between patients with psoriatic arthritis (PsA), hand osteoarthritis (hand-OA) and a pain-free control group and differences between patients with and without concomitant fibromyalgia (cFM).

METHODS

All patients and pain-free controls were assessed using pressure pain thresholds (PPT), temporal summation of pain (TSP), conditioned pain modulation (CPM) and clinical pain intensities. Psychological distress was assessed with the Hospital Anxiety and Depression Scale, Pain Catastrophizing Scale, and Pittsburgh Sleep Quality Index. Disability was assessed with the Health Assessment Questionnaire and pain quality with the painDETECT questionnaire. cFM was identified using the revised 2016 American College of Rheumatology diagnostic criteria.

RESULTS

Patients with hand-OA (n = 75) or PsA (n = 58) had statistically significant lower PPTs and CPM, greater TSP, and higher scores of psychological distress (p < 0.05) than controls (n = 20). Patients with cFM (58%) had higher scores of depression (p = 0.001), anxiety (p = 0.004), catastrophizing (p = 0.012), disability (p < 0.001), higher painDETECT score (p = 0.001), TSP (p = 0.027), and reduced sleep quality (p = 0.021) when compared to patients without cFM.

CONCLUSION

Patients with hand-OA and PsA exhibited signs of pain sensitization and a higher degree of psychological distress and disability than pain-free individuals. Patients with cFM had greater TSP, painDETECT score, disability, catastrophizing, and reduced sleep quality, than patients without, indicating greater degree of pain sensitization, psychological burden, and disability.

STATEMENT OF SIGNIFICANCE

This paper shows that a significant proportion of patients with hand osteoarthritis and psoriatic arthritis with moderate pain intensity have significantly increased signs of pain sensitization and markers of psychological distress. A large proportion of these patients fulfil the criteria for concomitant fibromyalgia and these patients show even greater propensity towards pain sensitization and psychological distress.

Influence of comorbidities not associated with fibromyalgia on neuropathic pain in patients with psoriatic arthritis: relationship with clinical parameters

Objective

Neuropathic pain (NP) may influence disease activity assessment in patients with psoriatic arthritis, this relationship being traditionally based on the presence of concomitant fibromyalgia. We analyzed the influence of other comorbidities on NP and the relationship between pain and various clinical parameters.

Methods

A cross-sectional study was conducted in patients diagnosed with psoriatic arthritis, excluding patients with a previous diagnosis of fibromyalgia, depression, anxiety, diabetes and/or dyslipidemia under treatment. NP was identified using the painDETECT questionnaire (score > 18). Obesity and related clinical parameters, anxious and depressive symptoms, sleep quality and fatigue were assessed as comorbidities. Disease activity was measured using the clinical Disease Activity Index for Psoriatic Arthritis (cDAPSA) in peripheral involvement, the ASDAS-PCR in axial involvement, functioning and disease impact were measured using the Health Assessment Questionnaire-Disability Index and 12-item Psoriatic Arthritis Impact of Disease questionnaire, respectively.

Results

Overall, 246 patients were included (136 men; 55%). The mean age was 53.4 ± 11.0 years. Forty-two patients had NP (17.1%). Patients with NP had higher leptin levels (OR: 1.03, 95% CI: 1.007-1.056; p < 0.01) and poor sleep quality (OR: 1.20, 95% CI: 1.09-1.297; p < 0.001). Patients with NP also had greater fatigue NRS (6.2 ± 2.2 vs. 2.4 ± 0.19, p < 0.001). Patients with NP had higher cDAPSA score (17.3 ± 5.4 vs. 8.9 ± 6.5, p < 0.001), poorer functioning (1.1 ± 0.5 vs. 0.4 ± 0.5, p < 0.001) and greater disease impact (6.1 ± 1.7 vs. 2.6 ± 1.9, p < 0.001).

Conclusion

NP was correlated with sleep quality and serum leptin and may be associated with worse disease activity, functioning and disease impact.

Pain in Parkinson disease: mechanistic substrates, main classification systems, and how to make sense out of them

ABSTRACT

Parkinson disease (PD) affects up to 2% of the general population older than 65 years and is a major cause of functional loss. Chronic pain is a common nonmotor symptom that affects up to 80% of patients with (Pw) PD both in prodromal phases and during the subsequent stages of the disease, negatively affecting patient's quality of life and function. Pain in PwPD is rather heterogeneous and may occur because of different mechanisms. Targeting motor symptoms by dopamine replacement or with neuromodulatory approaches may only partially control PD-related pain. Pain in general has been classified in PwPD according to the motor signs, pain dimensions, or pain subtypes. Recently, a new classification framework focusing on chronic pain was introduced to group different types of PD pains according to mechanistic descriptors: nociceptive, neuropathic, or neither nociceptive nor neuropathic. This is also in line with the International Classification of Disease-11 , which acknowledges the possibility of chronic secondary musculoskeletal or nociceptive pain due to disease of the CNS. In this narrative review and opinion article, a group of basic and clinical scientists revise the mechanism of pain in PD and the challenges faced when classifying it as a stepping stone to discuss an integrative view of the current classification approaches and how clinical practice can be influenced by them. Knowledge gaps to be tackled by coming classification and therapeutic efforts are presented, as well as a potential framework to address them in a patient-oriented manner.

Neuropathic pain; what we know and what we should do about it

Neuropathic pain can result from injury to, or disease of the nervous system. It is notoriously difficult to treat. Peripheral nerve injury promotes Schwann cell activation and invasion of immunocompetent cells into the site of injury, spinal cord and higher sensory structures such as thalamus and cingulate and sensory cortices. Various cytokines, chemokines, growth factors, monoamines and neuropeptides effect two-way signalling between neurons, glia and immune cells. This promotes sustained hyperexcitability and spontaneous activity in primary afferents that is crucial for onset and persistence of pain as well as misprocessing of sensory information in the spinal cord and supraspinal structures. Much of the current understanding of pain aetiology and identification of drug targets derives from studies of the consequences of peripheral nerve injury in rodent models. Although a vast amount of information has been forthcoming, the translation of this information into the clinical arena has been minimal. Few, if any, major therapeutic approaches have appeared since the mid 1990's. This may reflect failure to recognise differences in pain processing in males vs. females, differences in cellular responses to different types of injury and differences in pain processing in humans vs. animals. Basic science and clinical approaches which seek to bridge this knowledge gap include better assessment of pain in animal models, use of pain models which better emulate human disease, and stratification of human pain phenotypes according to quantitative assessment of signs and symptoms of disease. This can lead to more personalized and effective treatments for individual patients. Significance statement: There is an urgent need to find new treatments for neuropathic pain. Although classical animal models have revealed essential features of pain aetiology such as peripheral and central sensitization and some of the molecular and cellular mechanisms involved, they do not adequately model the multiplicity of disease states or injuries that may bring forth neuropathic pain in the clinic. This review seeks to integrate information from the multiplicity of disciplines that seek to understand neuropathic pain; including immunology, cell biology, electrophysiology and biophysics, anatomy, cell biology, neurology, molecular biology, pharmacology and behavioral science. Beyond this, it underlines ongoing refinements in basic science and clinical practice that will engender improved approaches to pain management.

A systematic review and meta-analysis of questionnaires to screen for pain sensitisation and neuropathic like pain in inflammatory arthritis

BACKGROUND

Targeted pain relief is a major unmet medical need for patients with inflammatory arthritis (IA), where approximately 40% of patients experience persistent pain. Self-reported questionnaires which report on pain sensitivity and neuropathic like pain may provide an insight into certain pain types to guide targeted treatment.

OBJECTIVE

In this systematic review and meta-analysis we evaluated self-reported pain sensitivity and neuropathic like pain in subjects with IA, as defined by questionnaires.

METHODS

MEDLINE, Embase, Web of Science, PsycINFO and google scholar were searched for publications and conference abstracts, reporting on pain sensitivity and neuropathic pain using painDETECT, DN4, LANSS, CSI, PSQ and McGill pain questionnaire in adult patients with IA. Risk of bias was assessed using National Institute of Health Quality Assessment Tool. Meta-analysis according to individual questionnaire criteria, was undertaken.

RESULTS

63 studies (38 full text and 25 conference abstracts) were included in the review, reporting on a total of 13,035 patients. On meta-analysis, prevalence of pain sensitivity/neuropathic like pain in IA was 36% (95% CI 31-41%) according to painDETECT, 31% (95% CI 26-37%) according to the DN4, 40% (95% CI 32-49%) according to the LANSS and 42% (95% CI 34-51%) according to the CSI. On meta-regression, prevalence of pain sensitivity/neuropathic pain in RA was significantly lower than SpA (p = 0.01) and PsA (p = 0.002) using the painDETECT questionnaire. Across all questionnaires, pain sensitivity and neuropathic like pain were significantly associated with worse pain severity, disease activity, disability, quality of life and anxiety and depression measures. Studies reporting on whether neuropathic like pain is a predictor of treatment outcome were inconsistent.

CONCLUSION

Pain sensitivity and neuropathic like pain contribute to pain perception in up to 42% of patients with IA. Despite substantial heterogeneity between studies on meta-analysis, this review highlights the large proportion of patients with IA who may experience pain due to underlying mechanisms other than, or in addition to, synovial inflammation.

A JAK Inhibitor for Treatment of Rheumatoid Arthritis: The Baricitinib Experience

Baricitinib, an oral selective Janus kinase (JAK)1/JAK2 inhibitor, is approved as monotherapy or in combination with methotrexate for treating adults with moderate-to-severe active rheumatoid arthritis (RA) and provides improvements in clinical signs, symptoms and patient-reported outcomes. Currently, baricitinib is approved for treating RA in more than 75 countries. In several pivotal Phase II and III RA trials (RA-BALANCE, RA-BEGIN, RA-BEAM, RA-BUILD, RA-BEACON, RA-BEYOND), up to seven years of baricitinib treatment was well tolerated and provided rapid and sustained efficacy, which was confirmed in real-world settings. Safety signals for another JAK inhibitor, tofacitinib, have emerged, as observed in the post-marketing Phase IIIb/IV trial Oral Rheumatoid Arthritis Trial (ORAL) Surveillance; safety signals were subsequently highlighted in a retrospective study of baricitinib and consequently new recommendations and warnings and precautions for all JAK inhibitors have been issued. Ongoing studies to further characterise and clarify the benefit:risk of JAK inhibitors include registries and controlled trials. This capstone review summarises clinical and real-world data outlining the benefit:risk profile of baricitinib, confirming that the improved disease activity and physical function of patients with RA treated with this JAK inhibitor observed in clinical trials is translated into effectiveness in clinical practice, with a low rate of discontinuations.

Pain in the joints and beyond; the challenge of rheumatoid arthritis

Pain is a common and often debilitating symptom for people living with rheumatoid arthritis. Although pain is a generic feature of inflammation and often improves with successful treatment that targets inflammatory pathways, pain experience can persist. Emerging data suggest that the magnitude of pain relief might vary according to the therapeutic target of pharmacological intervention within the inflammatory cascade. Both inflammatory and non-inflammatory causes contribute to the pain experience, which depends on tissue origin, peripheral sensory mechanisms and their transmission, integration, and interpretation within the nervous system. Contemporary neuroimaging is transforming our understanding of these mechanisms and the role of sensory, emotional, and cognitive contributions to the experience of pain. This understanding paves the way for therapeutic approaches that recognise the existence of multiple, cognitively driven, supraspinal mechanisms for pain modulation and could complement pharmacological inflammation suppression. Such approaches include neuropsychological interventions that have the potential to modify human brain cortical structure and reduce suffering that is often associated with pain experience.

Guselkumab provides sustained domain-specific and comprehensive efficacy using composite indices in patients with active psoriatic arthritis

OBJECTIVES

To evaluate the efficacy of guselkumab for the treatment of active PsA utilizing composite indices.

METHODS

Data were pooled from the phase 3 DISCOVER-1 (n = 381) and DISCOVER-2 (n = 739) studies. In both studies, patients were randomized 1:1:1 to subcutaneous guselkumab 100 mg every 4 weeks (Q4W); guselkumab 100 mg at week 0, week 4, then Q8W; or placebo Q4W with crossover to guselkumab 100 mg Q4W at week 24. Composite indices used to assess efficacy through week 52 included Disease Activity Index for Psoriatic Arthritis (DAPSA), Psoriatic Arthritis Disease Activity Score (PASDAS), minimal disease activity (MDA), and very low disease activity (VLDA). Through week 24, treatment failure rules were applied. Through week 52, non-responder imputation was used for missing data.

RESULTS

Greater proportions of guselkumab- than placebo-treated patients achieved DAPSA low disease activity (LDA) and remission, PASDAS LDA and VLDA, MDA, and VLDA at week 24 vs placebo (all unadjusted P < 0.05). At week 52, in the guselkumab Q4W and Q8W groups, respectively, response rates were as follows: DAPSA LDA, 54.2% and 52.5%; DAPSA remission, 18.2% and 17.6%; PASDAS LDA, 45.3% and 41.9%; PASDAS VLDA, 16.9% and 19.5%; MDA, 35.9% and 30.7%; and VLDA, 13.1% and 14.4%. In the placebo-crossover-to-guselkumab group, response rates for all composite indices increased after patients switched to guselkumab, from week 24 through week 52.

CONCLUSION

Treatment with guselkumab provided robust and sustained benefits across multiple PsA domains through 1 year, indicating that guselkumab is an effective therapy for the diverse manifestations of PsA.

TRIAL REGISTRATION

NCT03162796; NCT03158285.

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

Axial Spondyloarthritis: Reshape the Future-From the "2022 GISEA International Symposium"

The term "axial spondyloarthritis" (axSpA) refers to a group of chronic rheumatic diseases that predominantly involve the axial skeleton and consist of ankylosing spondylitis, reactive arthritis, arthritis/spondylitis associated with psoriasis (PsA) and arthritis/spondylitis associated with inflammatory bowel diseases (IBD). Moreover, pain is an important and common symptom of axSpA. It may progress to chronic pain, a more complicated bio-psychosocial phenomena, leading to a significant worsening of quality of life. The development of the axSpA inflammatory process is grounded in the complex interaction between genetic (such as HLA B27), epigenetic, and environmental factors associated with a dysregulated immune response. Considering the pivotal contribution of IL-23 and IL-17 in axSpA inflammation, the inhibition of these cytokines has been evaluated as a potential therapeutic strategy. With this context, here we discuss the main pathogenetic mechanisms, therapeutic approaches and the role of pain in axSpA from the 2022 International GISEA/OEG Symposium.

High-resolution ultrasound of peripheral neuropathies in rheumatological patients: An overview of clinical applications and imaging findings

Peripheral neuropathies are surprisingly common and can be associated with a number of conditions, including rheumatological diseases. Whether the co-existence of peripheral neuropathies with rheumatological disorders is coincidental or related to a common pathogenic mechanism, these disabling conditions can affect the outcome of rheumatological patients and should be targeted with specific treatment. The clinical presentation of peripheral neuropathy can be multifaceted and difficult to recognize in polysymptomatic patients. However, physicians adopting state-of-art diagnostic strategies, including nerve imaging, may improve the detection rate and management of neuropathies. In particular, a diagnostic approach relying exclusively on clinical history and nerve conduction studies may not be sufficient to disclose the etiology of the nerve damage and its anatomical location and thus requires integration with morphological studies. High-Resolution Ultrasound (HRUS) is increasingly adopted to support the diagnosis and follow-up of both joint disorders in rheumatology and peripheral neuropathies of different etiologies. In this review, the different types of nerve disorders associated with the most common syndromes of rheumatological interest are discussed, focusing on the distinctive sonographic features.

Nöropatik ağrı aksiyal spondiloartritte gözden kaçan bir semptom mu?

Amaç: Aksiyal spondiloartitler (axSpA) kronik inflamatuar romatolojik hastalıklardan olup ağrı yaşam kalitelerini etkileyen en sık semptomdur. Literatürde ağrının her zaman inflamasyonla korele olmadığı gösterilmiştir. Bu çalışma ile aksiyal spondiloartrit hastalarında nöropatik ağrının frekansının gösterilmesi ve nöropatik ağrı ile hasta özelliklerinin arasındaki ilişkinin gösterilmesi amaçlanmıştır. Gereç ve Yöntem: Kliniğimizde Ocak- Mart 2019 ayları arasında takip edilen, Assessment of SpondyloArthritis International Society klasifikasyon kriterlerine göre axSpA kabul edilen hastalar çalışmaya dahil edilmiştir. Nöropatik ağrı Douleur Neuropathique en 4 Questions (DN4) ölçeği ile değerlendirildi. Bulgular: Seksen yedi axSpa hastası çalışmaya dahil edildi. Hastaların 30’unda DN4 ölçeğine göre (DN4 >4) nöropatik ağrı var kabul edildi. Nöropatik ağrı aktif hasta grubunda (ASDAS- CRP ve BASDAI’ ye göre) daha fazla saptandı. DN4 skoru ASDAS- CRP ve BASDAI skoru ile orta düzeyde korele saptandı. Hasta eğitim düzeyi ile DN4 skoru arasında hafif düzeyde korelasyon saptandı. Sonuç: Çalışmamızda axSpA hastalarında inflamatuvar ağrıya ek olarak nöropatik ağrının görülebileceği ve hastalık aktivitesi ile korele olabileceği gösterildi. Nöropatik ağrı hastaların yaşam kalitesini bozduğu, sosyal ve emosyonel bozukluklara yol açtığı literatürde gösterilmiştir. Hastalar standart anti inflamatuvar tedavi yaklaşımlarından fayda görmeyebilir. AxSpA hastalarında nöropatik ağrının değerlendirilmesi önem kazanmaktadır. AxSpA hastalarında nöropatik ağrının tanı ve tedavi sürecinde ileri çalışmalara gereksinim duyulmaktadır.

Identifying and Quantifying the Role of Inflammation in Pain Reduction for Patients With Psoriatic Arthritis Treated With Tofacitinib: A Mediation Analysis

INTRODUCTION

Pain is a multidimensional factor and core domain of psoriatic arthritis (PsA). This analysis aimed to quantify the role of potential inflammation-associated outcomes on pain reduction in patients with PsA receiving tofacitinib, using mediation modeling.

METHODS

Pooled data were from two phase 3 studies (OPAL Broaden and OPAL Beyond) of patients with active PsA treated with tofacitinib 5 mg twice daily or placebo. Mediation modeling was utilized to quantify the indirect effects (via Itch Severity Item [ISI], C-reactive protein [CRP] levels, swollen joint count [SJC], Psoriasis Area and Severity Index [PASI], and enthesitis [using Leeds Enthesitis Index]) and direct effects (representing all other factors) of tofacitinib treatment on pain improvement.

RESULTS

The initial model showed that tofacitinib treatment affects pain, primarily indirectly, via ISI, CRP, SJC, PASI, and enthesitis (overall 84.0%; P = 0.0009), with 16.0% (P = 0.5274) attributable to the direct effect. The model was respecified to exclude SJC and PASI. Analysis of the final model revealed that 29.5% (P = 0.0579) of tofacitinib treatment effect on pain was attributable to the direct effect, and 70.5% (P < 0.0001) was attributable to the indirect effect. ISI, CRP, and enthesitis mediated 37.4% (P = 0.0002), 15.3% (P = 0.0107), and 17.8% (P = 0.0157) of the tofacitinib treatment effect on pain, respectively.

CONCLUSIONS

The majority of the effect of tofacitinib on pain was collectively mediated by itch, CRP, and enthesitis, with itch being the primary mediator of treatment effect.

TRIAL REGISTRATION

NCT01877668, NCT01882439. GRAPHICAL PLS.

The effect of tofacitinib on residual pain in patients with rheumatoid arthritis and psoriatic arthritis

OBJECTIVE

Post hoc analysis of pooled data from nine randomised controlled trials to assess the effect of tofacitinib (oral Janus kinase inhibitor for treatment of rheumatoid arthritis (RA) and psoriatic arthritis (PsA)) on residual pain in patients with RA or PsA with abrogated inflammation.

METHODS

Patients who received ≥1 dose of tofacitinib 5 mg twice daily, adalimumab or placebo with/without background conventional synthetic disease-modifying antirheumatic drugs and had abrogated inflammation (swollen joint count (SJC)=0 and C reactive protein (CRP)<6 mg/L) after 3 months' therapy were included. Assessments included Patient's Assessment of Arthritis Pain at month 3 (Visual Analogue Scale [VAS] 0-100 mm). Scores were summarised descriptively; treatment comparisons assessed by Bayesian network meta-analyses (BNMA).

RESULTS

From the total population with RA/PsA, 14.9% (382 of 2568), 17.1% (118 of 691) and 5.5% (50 of 909) of patients receiving tofacitinib, adalimumab and placebo, respectively, had abrogated inflammation after 3 months' therapy. Patients with RA/PsA with abrogated inflammation receiving tofacitinib/adalimumab had higher baseline CRP versus placebo; patients with RA receiving tofacitinib/adalimumab had lower SJC and longer disease duration versus placebo. Median residual pain (VAS) at month 3 was 17.0, 19.0 and 33.5 in patients with RA treated with tofacitinib, adalimumab or placebo, and 24.0, 21.0 and 27.0 in patients with PsA, respectively. Residual pain reductions with tofacitinib/adalimumab versus placebo were less prominent in patients with PsA versus patients with RA, with no significant differences between tofacitinib/adalimumab, per BNMA.

CONCLUSION

Patients with RA/PsA with abrogated inflammation receiving tofacitinib/adalimumab had greater residual pain reduction versus placebo at month 3. Results were similar between tofacitinib and adalimumab.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov registry (NCT00960440; NCT00847613; NCT00814307; NCT00856544; NCT00853385; NCT01039688; NCT02187055; NCT01877668; NCT01882439).

The role of kappa opioid receptors in immune system - An overview

Opioids are one of the most effective anti-nociceptive agents used in patients with cancer pain or after serious surgery in most countries. The endogenous opioid system participates in pain perception, but recently its role in inflammation was determined. κ-opioid receptors (KOP receptors), a member of the opioid receptor family, are expressed in the central and peripheral nervous system as well as on the surface of different types of immune cells, e.g. T cells, B cells and monocytes. In this review, we focused on the involvement of KOP receptors in the inflammatory process and described their function in a number of conditions in which the immune system plays a key role (e.g. inflammatory bowel disease, arthritis, subarachnoid hemorrhage, vascular dysfunction) and inflammatory pain. We summed up the application of known KOP ligands in pathophysiology and we aimed to shed new light on KOP receptors as important elements during inflammation.

Neuropathic‐like pain symptoms in inflammatory hand osteoarthritis lower quality of life and may not decrease under prednisolone treatment

Background

Pain is common in hand osteoarthritis (OA) and multiple types may occur. We investigated the prevalence, associated patient characteristics, influence on health‐related quality of life (HR‐QoL) and response to anti‐inflammatory treatment of neuropathic‐like pain in inflammatory hand OA.

Methods

Data were analysed from a 6‐week, randomized, double‐blind, placebo‐controlled trial investigating prednisolone treatment in 92 patients with painful inflammatory hand OA. Neuropathic‐like pain was measured with the painDETECT questionnaire. Associations between baseline characteristics and baseline neuropathic‐like pain were analysed with ordinal logistic regression, association of baseline neuropathic‐like pain symptoms with baseline HR‐QoL with linear regression, painDETECT and visual analogue scale (VAS) change from baseline to week 6 and interaction of painDETECT with prednisolone efficacy on VAS pain change from baseline to week 6 with generalized estimating equations (GEE).

Results

Of 91 patients (79% female, mean age 64) with complete painDETECT data at baseline, 53% were unlikely to have neuropathic‐like pain, 31% were indeterminate and 16% were likely to have neuropathic‐like pain. Neuropathic‐like pain was associated with female sex, less radiographic damage and more comorbidities. Patients with neuropathic‐like pain had lower HR‐QoL (PCS‐6.5 [95% CI −10.4 to −2.6]) than those without. Neuropathic‐like pain symptoms remained under prednisolone treatment and no interaction was seen between painDETECT and prednisolone efficacy on VAS pain.

Conclusions

In this study, 16% of inflammatory hand OA patients had neuropathic‐like pain. They were more often female, had more comorbidities and had lower QoL than those without. Neuropathic‐like pain symptoms remained despite prednisolone treatment and did not seem to affect the outcome of prednisolone treatment.

Significance

Pain is the dominant symptom in hand OA, with an unclear aetiology. In this study, we found that neuropathic‐like pain may play a role in hand OA, that it showed associations with female sex, younger age and more comorbidities and that it lowered health‐related quality of life in hand OA. Neuropathic‐like pain in hand OA seems resistant to prednisolone therapy but did not seem to interfere with the treatment of inflammatory pain with prednisolone.

Mediators of Neuropathic Pain; Focus on Spinal Microglia, CSF-1, BDNF, CCL21, TNF-α, Wnt Ligands, and Interleukin 1β

Intractable neuropathic pain is a frequent consequence of nerve injury or disease. When peripheral nerves are injured, damaged axons undergo Wallerian degeneration. Schwann cells, mast cells, fibroblasts, keratinocytes and epithelial cells are activated leading to the generation of an “inflammatory soup” containing cytokines, chemokines and growth factors. These primary mediators sensitize sensory nerve endings, attract macrophages, neutrophils and lymphocytes, alter gene expression, promote post-translational modification of proteins, and alter ion channel function in primary afferent neurons. This leads to increased excitability and spontaneous activity and the generation of secondary mediators including colony stimulating factor 1 (CSF-1), chemokine C-C motif ligand 21 (CCL-21), Wnt3a, and Wnt5a. Release of these mediators from primary afferent neurons alters the properties of spinal microglial cells causing them to release tertiary mediators, in many situations via ATP-dependent mechanisms. Tertiary mediators such as BDNF, tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and other Wnt ligands facilitate the generation and transmission of nociceptive information by increasing excitatory glutamatergic transmission and attenuating inhibitory GABA and glycinergic transmission in the spinal dorsal horn. This review focusses on activation of microglia by secondary mediators, release of tertiary mediators from microglia and a description of their actions in the spinal dorsal horn. Attention is drawn to the substantial differences in the precise roles of various mediators in males compared to females. At least 25 different mediators have been identified but the similarity of their actions at sensory nerve endings, in the dorsal root ganglia and in the spinal cord means there is considerable redundancy in the available mechanisms. Despite this, behavioral studies show that interruption of the actions of any single mediator can relieve signs of pain in experimental animals. We draw attention this paradox. It is difficult to explain how inactivation of one mediator can relieve pain when so many parallel pathways are available.

Similarities and differences between non-radiographic and radiographic axial spondyloarthritis: The patient perspective from the Spanish atlas

AIM

Although non-radiographic axial spondyloarthritis (EspAax-nr) is well understood within health institutions, being considered along with radiographic EspAax (EspAax-r) as part of the same disease spectrum, patient understanding is unknown. The aim is to describe the patient's knowledge of the EspAax-nr entity.

METHODS

Atlas 2017, promoted by the Spanish Federation of Spondylarthritis Associations (CEADE), aims to comprehensively understand the reality of EspAax patients from a holistic approach. A cross-sectional on-line survey of unselected patients with self-reported EspAax diagnosis from Spain was conducted. Participants were asked to report their diagnosis. Socio-demographic, disease characteristics and patient-reported outcomes (PROs) were compared between those patients self-reporting as EspAax-nr and EspAax-r.

RESULTS

634 EspAax patients participated. Mean age 45.7±10.9 years, 50.9% female and 36.1% university-educated. 35 (5.2%) self-reported as EspAax-nr. Compared to EspAax-r patients, those with EspAax-nr were more frequently women (48.6% vs 91.4%, p<0.001), had longer diagnostic delay (10.1±8.9 vs 8.5±7.6 years), higher psychological distress (GHQ-12: 7.5±4.9 vs 5.6±4.4) and similar degree of disease activity (BASDAI: 5.7±2.1 vs 5.7±2.0), and unemployment rates (20.0% vs 21.6%). 20.0% of EspAax-nr received biologics vs 36.9% of EspAax-r, p=0.043. Visits to the rheumatologist in the past year were similar in both groups (3.8±4.5 vs 3.2±3.8), while GP visits were much higher within EspAax-nr (8.0±10.7 vs 4.9±13.3 p=0.003).

CONCLUSION

For the first time, EspAax-nr characteristics and PROs have been analyzed from the patient's perspective. Both groups reported similar trends with the exception of EspAax-nr being more frequently women, younger, having longer diagnostic delay and lower use of biologic therapy.

The effect of flaxseed with or without anti-inflammatory diet in patients with rheumatoid arthritis, a randomized controlled trial

PURPOSE

Beneficial effect of long-chain ω-3 fatty acids against symptoms of rheumatoid arthritis (RA) has been indicated in previous studies. We examined the effect of flaxseed and anti-inflammatory diet in patients with RA.

METHODS

The 12-week intervention was performed on 120 patients with RA who were randomized to three groups of flaxseed (30 g/day) plus anti-inflammatory diet (AIF group), flaxseed (30 g/day) plus regular diet (RF group), and roasted wheat (30 g/day) plus regular diet (RW group). Disease Activity Score 28-joints (DAS28), health assessment questionnaire (HAQ) disability and pain, quality of life, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor, and anti-cyclic citrullinated peptides (anti-CCP) were measured before and after trial. Analysis was performed using per-protocol and intention-to-treat (ITT) approaches.

RESULTS

One hundred and two patients completed the protocol. Flaxseed decreased DAS28 in RF group compared to RW (- 0.87 ± 1.11 vs. - 0.24 ± 0.78; P = 0.014). Pain severity (P ≤ 0.001), morning stiffness (P < 0.05), and disease feeling (P < 0.01) decreased significantly in AIF and RF groups. HAQ disability and quality of life measurements improved in all 3 groups, with a greater extent in AIF and RF groups (P < 0.001) compared to RW. Between-group differences were significant for DAS28, pain scores, and physical and mental health variables. ESR, CRP, anti-CCP, and rheumatoid factor were not different between groups. Results of ITT analysis did not cause much difference.

CONCLUSIONS

In conclusion, flaxseed may be used as a helpful adjuvant therapy for patients with RA. Calls are open for examining the effect of anti-inflammatory diet on RA symptoms.

TRIAL REGISTRATION NUMBER

Registered at irct.ir as IRCT20190923044858N1, February 6, 2020.

Is pain associated with premature mortality in patients with psoriatic arthritis? A nested case-control study using the DANBIO Register

OBJECTIVES

It has been hypothesized that the presence of chronic pain causes excess mortality. Since chronic pain is prevalent among patients with PsA this potential association should be explored. We aimed to investigate whether higher cumulative pain intensity is associated with an excess mortality risk in patients with PsA.

METHODS

A nested case-control study using data from the nationwide DANBIO Register (Danish Database for Biological Therapies in Rheumatology) Register and Danish healthcare registers. Cases were patients who died and corresponding to the date of death, matched on sex, year of birth and calendar period at the time of death with up to five controls. Exposure of interest was mean pain intensity reported during the time followed in routine rheumatology practice. Pain intensity was measured using a visual analogue scale from 0 to 100 and conditional logistic regression was used to calculate odds of mortality per 5 unit increase in pain while adjusting for confounders.

RESULTS

The cohort consisted of 8019 patients. A total of 276 cases were identified and matched with 1187 controls. Higher mean pain intensity was associated with increased odds of mortality [odds ratio 1.06 (95% CI 1.02, 1.10)] in the crude model, but there was no association [odds ratio 0.99 (95% CI 0.95, 1.03)] when adjusting for additional confounders. Factors shown to increase the odds of mortality were recent glucocorticoid use, concomitant chronic obstructive pulmonary disease, diabetes mellitus, cancer and cardiovascular disease.

CONCLUSION

These results indicate that experienced pain in itself is not associated with premature mortality in patients with PsA. However, recent glucocorticoid use and concurrent comorbidities were.

Harnessing Inflammation Resolution in Arthritis: Current Understanding of Specialized Pro-resolving Lipid Mediators' Contribution to Arthritis Physiopathology and Future Perspectives

The concept behind the resolution of inflammation has changed in the past decades from a passive to an active process, which reflects in novel avenues to understand and control inflammation-driven diseases. The time-dependent and active process of resolution phase is orchestrated by the endogenous biosynthesis of specialized pro-resolving lipid mediators (SPMs). Inflammation and its resolution are two forces in rheumatic diseases that affect millions of people worldwide with pain as the most common experienced symptom. The pathophysiological role of SPMs in arthritis has been demonstrated in pre-clinical and clinical studies (no clinical trials yet), which highlight their active orchestration of disease control. The endogenous roles of SPMs also give rise to the opportunity of envisaging these molecules as novel candidates to improve the life quality of rhematic diseases patients. Herein, we discuss the current understanding of SPMs endogenous roles in arthritis as pro-resolutive, protective, and immunoresolvent lipids.

Increased Levels of Omega-3 Fatty Acids and DHA Are Linked to Pain Reduction in Rheumatoid Arthritis Patients Treated with Janus Kinase Inhibitors

Although Janus kinase inhibitors (JAKi) could reduce patient-reported pain in rheumatoid arthritis (RA), their mechanism remains unclear. Therefore, we examined lipid metabolites change in JAKi-treated patients and evaluate their association with pain reduction. We used ¹H-NMR-based lipid/metabolomics to determine serum levels of lipid metabolites at baseline and week 24 of treatment. Serum levels of significant lipid metabolites were replicated by ELISA in 24 JAKi-treated and 12 tocilizumab-treated patients. Pain was evaluated with patients’ assessment on a 0–100 mm VAS, and disease activity assessed using DAS28. JAKi or tocilizumab therapy significantly reduced disease activity. Acceptable pain (VAS pain ≤20) at week 24 was observed in 66.7% of JAKi-treated patients, and pain decrement was greater than tocilizumab-treated patients (ΔVAS pain 70.0 vs. 52.5, p = 0.0595). Levels of omega-3 fatty acids and docosahexaenoic acid (DHA) were increased in JAKi-treated patients (median 0.55 mmol/L versus 0.71 mmol/L, p = 0.0005; 0.29 mmol/L versus 0.35 mmol/L, p = 0.0004; respectively), which were not observed in tocilizumab-treated patients. ELISA results showed increased DHA levels in JAKi-treated patients with acceptable pain (44.30 µg/mL versus 45.61 µg/mL, p = 0.028). A significant association of pain decrement with DHA change, not with DAS28 change, was seen in JAKi-treated patients. The pain reduction effect of JAKi probably links to increased levels of omega-3 fatty acids and DHA.

Part of pain labelled neuropathic in rheumatic disease might be rather nociplastic

Pain in rheumatic diseases is primarily due to mechanical or inflammatory mechanism, but neuropathic pain (NP) component is also occurring in many conditions and is probably underdiagnosed. The purpose of this article is to provide an overview of prevalence, pathophysiological and currently available treatment of NP in rheumatic diseases. When associated with clinical evaluation assessing neurological clinical signs and neuroanatomical distribution, Douleur Neuropathique 4 Questions, painDETECT, Leeds assessment of neuropathic symptoms and signs and Neuropathic Pain Questionnaire can detect NP component. Inflammatory or connective diseases, osteoarthritis, back pain or persistent pain after surgery are aetiologies that all may have a neuropathic component. Unlike nociceptive pain, NP does not respond to usual analgesics such as paracetamol and non-steroidal anti-inflammatory drugs. Entrapment neuropathy, peripheral neuropathy or small-fibre neuropathy are different aetiologies that can lead to NP. A part of the pain labelled neuropathic is rather nociplastic, secondary to a central sensitisation mechanism. Identifying the right component of pain (nociceptive vs neuropathic or nociplastic) could help to better manage pain in rheumatic diseases with pharmacological and non-pharmacological treatments.

Median time to pain improvement and the impact of baseline pain severity on pain response in patients with psoriatic arthritis treated with tofacitinib

BACKGROUND

Pain is a core domain of psoriatic arthritis (PsA). This post hoc analysis evaluated time to pain improvement and the impact of baseline pain severity on pain response in patients with PsA receiving tofacitinib.

METHODS

Data from two trials (NCT01877668; NCT01882439) in patients receiving tofacitinib 5 mg twice daily, placebo switching to tofacitinib 5 mg twice daily at month 3 (placebo-to-tofacitinib) or adalimumab (NCT01877668 only) were included. Improvement in pain (≥30%/≥50% decrease from baseline in Visual Analogue Scale pain score) was assessed; median time to initial (first post-baseline visit)/continued (first two consecutive post-baseline visits) pain improvement was estimated (Kaplan-Meier) for all treatment arms. A parametric model was used to determine the relationship between baseline pain severity and time to pain response in patients receiving tofacitinib.

RESULTS

At month 3, more patients experienced pain improvements with tofacitinib/adalimumab versus placebo. Median days (95% CI) to initial/continued pain improvements of ≥30% and ≥50%, respectively, were 55 (29-57)/60 (57-85) and 85 (57-92)/171 (90-not estimable (NE)) for tofacitinib, versus 106 (64-115)/126 (113-173) and 169 (120-189)/NE (247-NE) for placebo-to-tofacitinib. Pain improvements were also experienced more quickly for adalimumab versus placebo. Predicted time to ≥30%/≥50% pain improvement was shorter in patients with higher baseline pain versus lower baseline pain (tofacitinib arm only).

CONCLUSIONS

In patients with PsA, pain improvements were experienced by more patients, and more rapidly, with tofacitinib and adalimumab versus placebo. In those receiving tofacitinib, higher baseline pain was associated with faster pain improvements.

Fusion proteins of biologic agents in the treatment of rheumatoid arthritis (RA): A network meta-analysis

BACKGROUND

To evaluate the efficacy of fusion proteins biologics (Etanercept (ETN), Anakinra (ANA), and Abatacept) combinations in the treatment of rheumatoid arthritis (RA) using network meta-analysis to rank those according to their performance medicines. The performance of these processes is ranked according to the results of the analysis and an explanatory study of the possible results is carried out.

METHODS

Multiple databases including PubMed, EMBASE, and Cochrane Library were used to identify applicable articles and collect relevant data to analyze using STATA (14.0) software. The literature included in this study was divided into a combination of a placebo, methotrexate (MTX), and an observation group (1 of the 3 drugs). The last search date was December 12, 2019.

RESULTS

A total of 19 eligible randomized controlled trials of fusion proteins biologics were identified, a total of 1109 papers were included, and the results showed that the ETN + MTX had the highest probability of being the most clinically efficacious intervention, with a surface under the cumulative ranking curve of 91.6, was significantly superior (P < .05). Patients who had received ETN or ETN + MTX or ANA had effective compared with patients who had received placebo (95% CI 1.28%-8.47%; 1.92%-19.18%; 1.06%-10.45%).

CONCLUSIONS

1. The combination of ETN and MTX had the highest probability of optimal treatment compared to other drugs and 2. ENT, ENT + MTX, and ANA were effective in the treatment of RA compared to placebo.

Chronic pain and neuroinflammation

In rheumatology, chronic pain most often sets in after a musculoskeletal injury. Its persistence is not always due to the progression of the initial injury, but in some cases to the onset of central sensitization. Much scientific data suggests that this central sensitization is caused by multiple complex interactions between the nervous system and immune system. Afferent nerve fibers carrying pain information are responsible for peripheral sensitization partly linked to inflammation molecules. These afferent fibers release neurotransmitters in the dorsal root ganglion and dorsal horn of the spinal cord, capable of activating microglia, which are the local immune cells. The activated microglia will produce pro-inflammatory cytokines, chemokines and neuropeptides capable of interacting with the second-order neuron, but also segmental and descending inhibitory neurons. This is referred to as neuroinflammation, which will amplify the hypersensitivity of second-order neurons, otherwise called central sensitization. This neuroinflammation will be able to reach the higher brain structures, which are involved in pain modulation and the emotional and cognitive aspects of pain. The aim of this update is to describe the pathophysiology of chronic pain, incorporating the latest scientific data on neuroplasticity and neuroinflammation.

Mechanisms and Mediators of Pain in Chronic Inflammatory Arthritis

Purpose of the review

Pain in chronic inflammatory joint diseases is a common symptom reported by patients. Pain becomes of absolute clinical relevance especially when it becomes chronic, i.e., when it persists beyond normal healing times. As an operational definition, pain is defined chronic when it lasts for more than 3 months. This article aims to provide a review of the main mechanisms underlying pain in patients with chronic inflammatory joint diseases, discussing in particular their overlap.

Recent findings

While it may be intuitive how synovial inflammation or enthesitis are responsible for nociceptive pain, in clinical practice, it is common to find patients who continue to complain of symptoms despite optimal control of inflammation. In this kind of patients at the genesis of pain, there may be neuropathic or nociplastic mechanisms.

Summary

In the context of chronic inflammatory joint diseases, multiple mechanisms generally coexist behind chronic pain. It is the rheumatologist’s task to identify the mechanisms of pain that go beyond the nociceptive mechanisms, to adopt appropriate therapeutic strategies, including avoiding overtreatment of patients with immunosuppressive drugs. In this sense, future research will have to be oriented to search for biomarkers of non-inflammatory pain in patients with chronic inflammatory joint diseases.

Efficacy of tofacitinib in reducing pain in patients with rheumatoid arthritis, psoriatic arthritis or ankylosing spondylitis

Objective

To describe the efficacy of tofacitinib in reducing pain in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) or ankylosing spondylitis (AS) in a post-hoc analysis of randomised controlled trials.

Methods

Data were collected from patients in seven tofacitinib studies: six phase III (four RA, two PsA) and one phase II study (AS), and grouped into five analysis populations based on rheumatic disease diagnosis and category of prior inadequate response (IR) to treatment: conventional synthetic disease-modifying antirheumatic drugs-IR (RA and PsA), tumour necrosis factor inhibitors-IR (RA and PsA), or non-steroidal anti-inflammatory drugs-IR (AS). Only patients who received tofacitinib 5 or 10 mg twice daily or placebo were included. Pain assessments included: Patient’s Assessment of Arthritis Pain, Short-Form Health Survey 36v2 Question (Q)7 and Bodily Pain domain, Ankylosing Spondylitis Quality of Life Q9 and Q14, EuroQol Five Dimensions Pain/Discomfort dimension and Bath Ankylosing Spondylitis Disease Activity Index Q2 and Q3. Data were reported to month 6 (placebo to month 3) in the RA and PsA populations, and week 12 (tofacitinib and placebo) in the AS population.

Results

Overall, 3330 patients were included in this analysis. In the RA and PsA populations, pain improvements in tofacitinib-treated patients compared with placebo were observed at the earliest time point assessed and at month 3 (maintained to month 6). In the AS population, pain improvements compared with placebo were observed at week 12.

Conclusion

Tofacitinib was associated with rapid and sustained improvements across multiple pain measures in patients with inflammatory rheumatic musculoskeletal diseases.

Real-world experiences of the diagnosis process in Korean patients with ankylosing spondylitis based on a self-report questionnaire

Objectives

The diagnosis of ankylosing spondylitis (AS) is often delayed, which affects various clinical outcomes. This study examined the real-world situation of patients with AS during diagnosis and treatment.

Methods

Data were obtained from 26 tertiary care hospitals in Korea using a self-report questionnaire. The questionnaire assessed symptoms, pain, extra-articular manifestations, the initial pattern of pain before diagnosis, factors leading to delayed referral to rheumatology, time until receiving an AS diagnosis, comorbid diseases, treatment status, and disease education needs.

Results

Between September and October 2019, 1012 patients with AS completed the survey. Of these, 75.8% were men and 51.8% were in their 30s or 40s. Median disease duration was 76 months. The median time to diagnosis with AS was 12 months. When pain occurred, the medical departments most frequently visited first were orthopedic (61.5%) and rheumatology (18.7%) departments. The likelihood of the first visit being to the orthopedic department and the frequency of biologics use increased with the disease duration. The rates of uveitis, depressed mood, and comorbid diseases were higher in the group with delayed diagnosis.

Conclusions

Physicians should be aware of subtypes of AS that take longer to diagnose and comorbid diseases in the real-world clinical setting.

The Prognostic Value of Pain Phenotyping in Relation to Treatment Outcomes in Patients with Axial Spondyloarthritis Treated in Clinical Practice: A Prospective Cohort Study

Despite the control of inflammation, many patients with axial spondyloarthritis (axSpA) still report pain as a significant concern. Our objective was to explore the prognostic value of the painDETECT questionnaire (PDQ) in relation to treatment outcomes in axSpA patients treated in clinical practice. AxSpA patients with high disease activity initiating or switching a biological Disease-Modifying Antirheumatic Drug (bDMARD) were eligible. The PDQ score (range: −1 to 38) was used to distinguish participants with nociceptive pain (NcP) mechanisms from participants with a mixed pain mechanism (MP). The primary outcome was the proportion of individuals achieving a 50% improvement of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50) at 12 weeks; logistic regression analysis models were used to determine the prognostic value of the nociceptive pain phenotype. Changes in continuous outcomes such as the Assessment of SpondyloArthritis International Society (ASAS) core outcome domains were analyzed using analysis of covariance (ANCOVA). Health-related quality of life (HR-QoL) was addressed using the Medical Outcomes Study SF-36. During a period of 22 months, 49 axSpA patients were included. Twenty (41%) had an NcP phenotype according to the PDQ score. BASDAI50 responses were reported by 40% (8/20) and 28% (8/29) NcP and MP groups, respectively. However, a prognostic value was not found in relation to the primary outcome (crude odds ratio [95% confidence interval]: 1.75 [0.52 to 5.87]). Across most of the secondary outcomes, axSpA NcP phenotype patients were reported having the most improvements in the HR-QoL measures. These data indicate the influence of personalized management strategies according to patients’ pain phenotypes for stratification of axSpA patients in randomized controlled trials.

Why It Hurts: The Mechanisms of Pain in Rheumatoid Arthritis

Pain is a near-universal feature of rheumatoid arthritis, but peripheral joint inflammation may not suffice to explain the etiology of pain in all patients with rheumatoid arthritis. Inflammation in rheumatoid arthritis releases several algogens that may generate pain. Also, central nervous system processes may play a crucial role in the regulation and perpetuation of pain. Several methods for assessing pain in rheumatoid arthritis exist, and recently the role of assessing therapeutics in treating specific etiologies of pain has gained interest.

Assessment of Widespread and Extraarticular Pain in Psoriatic Arthritis: A Case-control Study

OBJECTIVE

A remarkable lack of detailed knowledge on pain areas in psoriatic arthritis (PsA) is present, and their clinical relevance is quite unknown. The main aim of the study was to explore pain areas in PsA, comparing them with those involved in patients with fibromyalgia (FM). In addition, a secondary aim was to investigate any possible association between pain areas and outcome measures in PsA.

METHODS

This was a case-control study on patients with PsA satisfying Classification Criteria for Psoriatic Arthritis criteria and patients with FM. In all patients with PsA and FM, a body chart filled in by the patient reporting pain areas in 80 body locations was performed. The Widespread Pain Index (WPI) was performed in all patients with PsA and FM. In all patients with PsA, an assessment of disease activity, treatment target, function, and impact of disease was carried out.

RESULTS

Fifty patients with PsA and 50 FM controls were evaluated. A significantly higher number of pain areas in the body chart and higher WPI scores were found in patients with FM when compared to patients with PsA. In PsA, the number of areas reported in the body chart significantly correlated with the Disease Activity Index for PsA, Health Assessment Questionnaire-Disability Index, and PsA Impact of Disease. Patients who showed a significantly high number of extraarticular pain areas involved were those who were not in remission/minimal disease activity, or who did not have a greater impact of disease or reduced function.

CONCLUSION

The main results showed that widespread and extraarticular pain was present in patients with PsA, showing that this nonarticular pain had an impact on important disease domains. The present study could contribute to an important aspect of this challenging and multifaceted disease-namely, the assessment of widespread pain.

[Pain in rheumatic diseases : What can biologics and JAK inhibitors offer?]

Persistent pain despite adequate inflammation control poses a big challenge in many rheumatic diseases for patients as well as physicians. The focus of drug development over the past years was on anti-inflammatory therapies. Enormous progress has been made and several treatment options have been added. It has been observed that pain triggered by inflammation can be effectively treated by inflammation control; however, the chronic pain component remains a problem, is little studied and specific treatment options are missing. Pain is influenced by inflammatory mediators, such as cytokines, which act on peripheral nociceptors and lead to peripheral sensitization. If inflammation continues, this can potentially lead to central sensitization and chronification of pain via immigration of immune cells and/or local activation of e.g. microglia. This leads to increasing autonomization and uncoupling of pain from the actual inflammatory process. The present review deals with the question if bDMARD or tsDMARD also show benefits concerning pain processes in addition to the profound inhibitory effects on inflammation. There are preclinical data that show an influence on sensitization following the use of cytokine inhibitors. On the other hand, so far clinical data show that bDMARDs as well as tsDMARDs consistently rapidly and reliably reduce nociceptive inflammatory pain across disease entities. An effect especially on the process of central sensitization and therefore on chronification of pain cannot be finally evaluated based on the currently available data.

The relationship between restless sleep and symptoms of the knee: data from the Osteoarthritis Initiative

OBJECTIVE

To examine the associations between restless sleep and knee symptoms among individuals with radiographically confirmed KOA.

METHODS

Cross-sectional and longitudinal associations were examined using Osteoarthritis Initiative (OAI) data. Participants with radiographic KOA (n = 2517) were asked how often sleep was restless in the past week over the 4 years, and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) was used to measure knee symptoms. Adjusted β coefficients (aβ) and 95% confidence intervals (CI) were derived from generalized estimating equations (GEEs) models stratified by sex.

RESULTS

One in 7 participants reported ≥ 3 nights with restless sleep. Cross-sectional analyses indicated that restless sleep 5-7 nights was associated with worse symptoms (Women: pain: aβ 1.93, 95% CI 1.12-2.74, stiffness: aβ 0.57, 95% CI 0.19-0.94, physical function: aβ 5.68, 95% CI 3.09-8.27; Men: pain: aβ = 1.85, 95% CI 0.85-2.86; stiffness: aβ 0.63, 95% CI 0.15-1.12; physical function: aβ 5.89, 95% CI 2.68-9.09) compared with < 1 night. Longitudinal analyses confirmed that more nights with restless sleep were associated with worse pain (P trend = 0.01) and function (P trend = 0.04) in women and physical function in men (P trend = 0.04), although estimates did not meet thresholds for minimal clinically meaningful differences.

CONCLUSION

While the analysis of cross-sectional data supported the association between restless sleep and KOA symptoms, such relationships were not confirmed in more robust longitudinal analysis. Further research examining whether sleep quality, duration, or disorders is associated with worsening symptoms in persons with KOA is warranted. Key Points • The prevalence of frequent restless sleep among persons with knee OA is not uncommon. • There were linear trends between frequency of restless sleep and self-reported symptoms of the knee in cross-sectional analyses. • In the more robust longitudinal analysis, despite the statistically significant linear trends observed between frequency of restless sleep and symptoms (women: pain and physical function; men: function), none appeared to reach the a priori selected ranges for minimally clinically relevant differences.

Interaction of pain and chronic inflammation

Rheumatic diseases are characterized by chronic inflammation of synovial joints and are often associated with persistent pain and increased pain sensitivity. The inflammatory process is a complex cascade of events involving several mediators, which can lead to a chronic condition of pain. Inflammation can stimulate angiogenesis, and angiogenesis can facilitate inflammation. Inflammatory pain arises from tissue damage via the sensitization of pain receptors (nociceptors). The main peripheral mechanism underlying nociceptive pain is a change in the activity of the nociceptors located in the affected anatomical structures (joints, tendons, and ligaments), which renders them more sensitive to normally painful stimuli (hyperalgesia) or normally non-painful stimuli (allodynia). Neuroimmune interaction has been considered to play an essential role in rheumatic disease. Neurogenic inflammation, which influences normal central nervous system signaling, leads to insufficient signaling/bioavailability of various cytokines. These central mechanisms play an important role in the increased pain sensitivity following inflammation and are responsible for the development of secondary hyperalgesia in regions beyond the injured tissue. Reduction of pain in rheumatic disease requires familiarity with various pain mechanisms.

Similarities and differences between non-radiographic and radiographic axial spondyloarthritis: The patient perspective from the Spanish atlas

AIM

Although non-radiographic axial spondyloarthritis (EspAax-nr) is well understood within health institutions, being considered along with radiographic EspAax (EspAax-r) as part of the same disease spectrum, patient understanding is unknown. The aim is to describe the patient's knowledge of the EspAax-nr entity.

METHODS

Atlas 2017, promoted by the Spanish Federation of Spondylarthritis Associations (CEADE), aims to comprehensively understand the reality of EspAax patients from a holistic approach. A cross-sectional on-line survey of unselected patients with self-reported EspAax diagnosis from Spain was conducted. Participants were asked to report their diagnosis. Socio-demographic, disease characteristics and patient-reported outcomes (PROs) were compared between those patients self-reporting as EspAax-nr and EspAax-r.

RESULTS

634 EspAax patients participated. Mean age 45.7±10.9 years, 50.9% female and 36.1% university-educated. 35 (5.2%) self-reported as EspAax-nr. Compared to EspAax-r patients, those with EspAax-nr were more frequently women (48.6% vs 91.4%, p<0.001), had longer diagnostic delay (10.1±8.9 vs 8.5±7.6 years), higher psychological distress (GHQ-12: 7.5±4.9 vs 5.6±4.4) and similar degree of disease activity (BASDAI: 5.7±2.1 vs 5.7±2.0), and unemployment rates (20.0% vs 21.6%). 20.0% of EspAax-nr received biologics vs 36.9% of EspAax-r, p=0.043. Visits to the rheumatologist in the past year were similar in both groups (3.8±4.5 vs 3.2±3.8), while GP visits were much higher within EspAax-nr (8.0±10.7 vs 4.9±13.3 p=0.003).

CONCLUSION

For the first time, EspAax-nr characteristics and PROs have been analyzed from the patient's perspective. Both groups reported similar trends with the exception of EspAax-nr being more frequently women, younger, having longer diagnostic delay and lower use of biologic therapy.

Patient-Centered Care in Psoriatic Arthritis-A Perspective on Inflammation, Disease Activity, and Psychosocial Factors

Psoriatic arthritis (PsA) is a seronegative spondyloarthropathy characterized by skin lesions, dactylitis, and enthesitis. Patients with PsA suffer from a variety of psychosocial difficulties and nonspecific symptoms early on in the disease course and continue to experience progressive disease due to delays in diagnosis and treatment. Symptoms initially viewed as somatization could lead to undertreatment and promote psychological distress, poor coping, and negative patient-provider relationships. Pain and fatigue are important complaints that affect the patient's perception and may need to be addressed with a multidisciplinary approach. Maladaptive cognitive responses can lead to a negative illness perception and impact patient beliefs and concerns over treatment, as well as nonadherence. An underlying inflammatory component in affective disorders has been examined, though whether and how it may interact mechanistically in PsA warrants interest. Cognitive behavioral therapy represents a nonpharmacological treatment modality that can be combined with cytokine-targeted therapy to address both somatic and psychological complaints. Future directions for research include: (1) Elucidating nonspecific manifestations (e.g., subclinical stage, differential with functional syndromes) of PsA and how they impact diagnosis and management; (2) characterizing immune-mediated components of mood disorders in PsA; and (3) whether a bidirectional approach with abrogating inflammation and psychotherapeutic support leads to improved outcomes.

The neuropathic phenotype of the K/BxN transgenic mouse with spontaneous arthritis: pain, nerve sprouting and joint remodeling

The adult K/BxN transgenic mouse develops spontaneous autoimmune arthritis with joint remodeling and profound bone loss. We report that both males and females display a severe sustained tactile allodynia which is reduced by gabapentin but not the potent cyclooxygenase inhibitor ketorolac. In dorsal horn, males and females show increased GFAP⁺ astrocytic cells; however, only males demonstrate an increase in Iba1⁺ microglia. In dorsal root ganglia (DRG), there is an increase in CGRP⁺, TH⁺, and Iba1⁺ (macrophage) labeling, but no increase in ATF3⁺ cells. At the ankle there is increased CGRP⁺, TH⁺, and GAP-43⁺ fiber synovial innervation. Thus, based on the changes in dorsal horn, DRG and peripheral innervation, we suggest that the adult K/BxN transgenic arthritic mice display a neuropathic phenotype, an assertion consistent with the analgesic pharmacology seen in this animal. These results indicate the relevance of this model to our understanding of the nociceptive processing which underlies the chronic pain state that evolves secondary to persistent joint inflammation.

K+ Channels in Primary Afferents and Their Role in Nerve Injury-Induced Pain

Sensory abnormalities generated by nerve injury, peripheral neuropathy or disease are often expressed as neuropathic pain. This type of pain is frequently resistant to therapeutic intervention and may be intractable. Numerous studies have revealed the importance of enduring increases in primary afferent excitability and persistent spontaneous activity in the onset and maintenance of peripherally induced neuropathic pain. Some of this activity results from modulation, increased activity and /or expression of voltage-gated Na⁺ channels and hyperpolarization-activated cyclic nucleotide–gated (HCN) channels. K⁺ channels expressed in dorsal root ganglia (DRG) include delayed rectifiers (K_v1.1, 1.2), A-channels (K_v1.4, 3.3, 3.4, 4.1, 4.2, and 4.3), KCNQ or M-channels (K_v7.2, 7.3, 7.4, and 7.5), ATP-sensitive channels (K_IR6.2), Ca²⁺-activated K⁺ channels (K_Ca1.1, 2.1, 2.2, 2.3, and 3.1), Na⁺-activated K⁺ channels (K_Ca4.1 and 4.2) and two pore domain leak channels (K_2p; TWIK related channels). Function of all K⁺ channel types is reduced via a multiplicity of processes leading to altered expression and/or post-translational modification. This also increases excitability of DRG cell bodies and nociceptive free nerve endings, alters axonal conduction and increases neurotransmitter release from primary afferent terminals in the spinal dorsal horn. Correlation of these cellular changes with behavioral studies provides almost indisputable evidence for K⁺ channel dysfunction in the onset and maintenance of neuropathic pain. This idea is underlined by the observation that selective impairment of just one subtype of DRG K⁺ channel can produce signs of pain in vivo. Whilst it is established that various mediators, including cytokines and growth factors bring about injury-induced changes in DRG function and excitability, evidence presently available points to a seminal role for interleukin 1β (IL-1β) in control of K⁺ channel function. Despite the current state of knowledge, attempts to target K⁺ channels for therapeutic pain management have met with limited success. This situation may change with the advent of personalized medicine. Identification of specific sensory abnormalities and genetic profiling of individual patients may predict therapeutic benefit of K⁺ channel activators.

JAK Inhibitors in Rheumatoid Arthritis: An Evidence-Based Review on the Emerging Clinical Data

Janus kinase (JAK) Inhibitors are the latest drug class of disease-modifying medication to emerge for the treatment of rheumatoid arthritis (RA). They are a small molecule-targeted treatment and are the first oral option to compare favourably to existing biologic disease-modifying anti-rheumatic drugs (DMARDs). Tofacitinib, baricitinib and upadacitinib are the first 3 JAK inhibitors to become commercially available in the field and are the core focus of this review. To date, they have demonstrated comparable efficacy to tumour necrosis factor (TNF) inhibitors in terms of American College of Rheumatology (ACR) response rates and disease activity (DAS28) scores with similar cost to the benchmark adalimumab. This narrative review article aims to synthesise and distil the key available trial data on JAK inhibitor efficacy and safety, along with their place in the ACR and European League Against Rheumatism (EULAR) guidelines for RA. The novel mechanism of action of the JAK/STAT pathway is highlighted along with the potential effects of modulating each pathway. The rapid onset of action, role in attenuation of central pain processing and effect on structural damage and radiographic progression are also all examined in detail. We also explore the latest meta-analyses and comparative performance of each of the 3 available JAKs in an effort to determine which is most efficacious and which has the most favourable safety profile. Post marketing concerns regarding thromboembolism risk and herpes zoster infection are also discussed. Additionally, we review the cost-benefit analyses of the available JAK inhibitors and address some of the pharmacoeconomic considerations for real-world practice in the UK and US by detailing the raw acquisition cost and the value they provide in comparison to the benchmark biologic adalimumab and the anchor DMARD methotrexate.

The burden of pain in rheumatoid arthritis: Impact of disease activity and psychological factors

BACKGROUND

Pain remains a prevalent symptom for rheumatoid arthritis (RA) patients despite a wide therapeutic choice. The objective of this study was to provide a multidimensional evaluation of pain.

METHODS

A total of 295 RA patients from 7 French rheumatology centres were enrolled in a cross-sectional study. Patients completed a chronic pain assessment questionnaire approved by the French National Authority for Health, the health assessment questionnaire (HAQ) as well as depression and anxiety scales (HAD, Beck Depression Inventory, STAI). Disease activity (DAS28) and ESR were recorded. A multivariate descriptive analysis was undertaken using principal component analysis (PCA).

RESULTS

38.4% of patients had a pain score > 40 mm/100, although 83% were on biological treatment and 38.7% were in remission based on the RA activity score. The PCA analysis found four axes representing 70% of total variance. The axes, per cent of variance and variables represented were as follows: (a) axis 1, 41% variance, anxiety and depression scores, sensory and affective qualifier score, HAQ and pain impact on daily life; (b) axis 2, 13% variance, disease activity score (DAS28) and pain relief with current treatment; (c) axis 3, 9% of variance, RA duration and radiographic score and (d) axis 4, 6% of variance, DAS28 and ESR. Moderate to severe pain was significantly associated with axes 1 and 2.

CONCLUSIONS

Despite a high proportion of patients on biological treatments, 38.4% of patients continue to experience moderate to severe pain. Pain is associated with the RA activity score, but also with the depression and anxiety scores.

SIGNIFICANCE

Substantial proportion of rheumatoid arthritis (RA) patients still experiences relevant pain, although more than 80% on biological treatment. Pain is primarily associated with anxiety and depression scores and with disease activity score. These findings highlight the need to assess patients' mental well-being alongside. Clinical measures of disease activity to better manage pain and guide treatment decisions.