Remaining Pain in Early Rheumatoid Arthritis Patients Treated With Methotrexate

Sinomenine ameliorates fibroblast-like synoviocytes dysfunction by promoting phosphorylation and nuclear translocation of CRMP2

ETHNOPHARMACOLOGICAL RELEVANCE

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial inflammation and arthritic pain. Sinomenine (SIN), derived from the rhizome of Chinese medical herb Qing Teng (scientific name: Sinomenium acutum (Thunb.) Rehd. Et Wils), has a longstanding use in Chinese traditional medicine for treating rheumatoid arthritis. It has been shown to possess anti-inflammatory, analgesic, and immunosuppressive effects with minimal side-effects clinically. However, the mechanisms governing its effects in treatment of joint pathology, especially on fibroblast-like synoviocytes (FLSs) dysfunction, and arthritic pain remains unclear.

AIM

This study aimed to investigate the effect and underlying mechanism of SIN on arthritic joint inflammation and joint FLSs dysfunctions.

MATERIALS AND METHODS

Collagen-induced arthritis (CIA) was induced in rats and the therapeutic effects of SIN on joint pathology were evaluated histopathologically. Next, we conducted a series of experiments using LPS-induced FLSs, which were divided into five groups (Naïve, LPS, SIN 10, 20, 50 μg/ml). The expression of inflammatory factors was measured by qPCR and ELISA. The invasive ability of cells was detected by modified Transwell assay and qPCR. Transwell migration and cell scratch assays were used to assess the migration ability of cells. The distribution and content of relevant proteins were observed by immunofluorescence and laser confocal microscopy, as well as Western Blot and qPCR. FLSs were transfected with plasmids (CRMP2 T514A/D) to directly modulate the post-translational modification of CRMP2 protein and downstream effects on FLSs function was monitored.

RESULTS

SIN alleviated joint inflammation in rats with CIA, as evidenced by improvement of synovial hyperplasia, inflammatory cell infiltration and cartilage damage, as well as inhibition of pro-inflammatory cytokines release from FLSs induced by LPS. In vitro studies revealed a concentration-dependent suppression of SIN on the invasion and migration of FLSs induced by LPS. In addition, SIN downregulated the expression of cellular CRMP2 that was induced by LPS in FLSs, but increased its phosphorylation at residue T514. Moreover, regulation of pCRMP2 T514 by plasmids transfection (CRMP2 T514A/D) significantly influenced the migration and invasion of FLSs. Finally, SIN promoted nuclear translocation of pCRMP2 T514 in FLSs.

CONCLUSIONS

SIN may exert its anti-inflammatory and analgesic effects by modulating CRMP2 T514 phosphorylation and its nuclear translocation of FLSs, inhibiting pro-inflammatory cytokine release, and suppressing abnormal invasion and migration. Phosphorylation of CRMP2 at the T514 site in FLSs may present a new therapeutic target for treating inflammatory joint's destruction and arthritic pain in RA.

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.

Joint tenderness at 3 months follow-up better predicts long-term pain than baseline characteristics in early rheumatoid arthritis patients

OBJECTIVE

To investigate pain course over time and to identify baseline and 3-month predictors of unacceptable pain with or without low inflammation in early RA.

METHODS

A cohort of 275 patients with early RA, recruited in 2012-2016, was investigated and followed for 2 years. Pain was assessed using a visual analogue scale (VAS; 0-100 mm). Unacceptable pain was defined as VAS pain >40, and low inflammation as CRP <10 mg/l. Baseline and 3-month predictors of unacceptable pain were evaluated using logistic regression analysis.

RESULTS

After 2 years, 32% of patients reported unacceptable pain. Among those, 81% had low inflammation. Unacceptable pain, and unacceptable pain with low inflammation, at 1 and 2 years was significantly associated with several factors at 3 months, but not at baseline. Three-month predictors of these pain states at 1 and 2 years were higher scores for pain, patient global assessment, and the health assessment questionnaire, and more extensive joint tenderness compared with the number of swollen joints. No significant associations were found for objective inflammatory measures.

CONCLUSION

A substantial proportion of patients had unacceptable pain with low inflammation after 2 years. Three months after diagnosis seems to be a good time-point for assessing the risk of long-term pain. The associations between patient reported outcomes and pain, and the lack of association with objective inflammatory measures, supports the uncoupling between pain and inflammation in RA. Having many tender joints, but more limited synovitis, may be predictive of long-term pain despite low inflammation in early RA.

Exploring the differences in serum metabolite profiles after intake of red meat in women with rheumatoid arthritis and a matched control group

PURPOSE

Studies have suggested that women with RA tend to avoid red meat more often than women without RA, based on their perception that it exacerbates their symptoms. Therefore, the aim of this study is to investigate and compare the postprandial metabolic response following the consumption of a red meat meal in patients with RA and a matched control group.

METHODS

Participants were challenged with a meal with red meat and blood samples were collected before and at 0.5, 1, 2, 3 and 5 h after the meal. Serum metabolites were quantified by Nuclear Magnetic Resonance (NMR) analysis. Orthogonal Projections to Latent Structures with Discriminant Analysis (OPLS-DA) was used to evaluate separation by metabolites due to diagnosis of RA or not and to identify changes in metabolites related to RA. Incremental area under the curve was calculated for univariate comparisons for 23 metabolites.

RESULTS

The matched groups, including 22 women with RA and 22 women without RA, did not differ significantly in age, body mass index, diet quality or reported physical activity. OPLS-DA models had a limited quality indicating that there were no differences in metabolite patterns between the groups. However, phenylalanine was significantly higher in concentration in women with RA compared to controls in both fasting and postprandial samples.

CONCLUSION

To conclude, this well-controlled postprandial intervention study found a significantly higher concentration of phenylalanine in both fasting and postprandial samples of women with RA compared to matched women without RA. These findings warrant further investigation in larger studies.

TRIAL REGISTRATION

The PIRA (Postprandial Inflammation in Rheumatoid Arthritis) trial is Registered at Clinicaltrials.gov (NCT04247009).

A Cross-Sectional Survey of Physicians' Knowledge and Awareness of Chronic Pain Associated with Rheumatoid Arthritis in Rheumatology Departments in Zhejiang Province, China

Objective

To assess physicians' knowledge and awareness of chronic pain associated with rheumatoid arthritis (RA) in Rheumatology departments throughout Zhejiang province to improve chronic pain relief in RA patients.

Methods

A cross-sectional questionnaire survey was conducted onsite and online among rheumatologists in tertiary and secondary hospitals across Zhejiang province, China. The questionnaire inquired about rheumatoid arthritis-related pain cognition, pain assessment, pain management protocols, and medication choice.

Results

Among the 150 questionnaires included, 98 were from tertiary hospitals, and 52 were from secondary hospitals. There was no difference in rheumatologists' perceptions of chronic pain in RA patients between tertiary and secondary hospitals. About 55.1% of rheumatologists from tertiary hospitals and 44.2% of rheumatologists from secondary hospitals utilized unstandardized pain assessment scales. About 46.9% of rheumatologists in tertiary hospitals and 36.5% of rheumatologists in secondary hospitals favored the numerical rating scale (NRS). About 87.8% of rheumatologists in tertiary hospitals and 71.7% of rheumatologists in secondary hospitals conducted pain assessment within 4 hours of admission. About 66.3% of rheumatologists working in tertiary hospitals and 32.7% of rheumatologists practicing in secondary hospitals believed their hospitals had pain departments. For RA patients who complained of pain for the first time, secondarily, or repeatedly, 48%, 26%, and 36.7% of rheumatologists preferred nonsteroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, and opioid analgesics, respectively. For RA patients with mild, moderate, or severe pain, 74%, 6%, and 16% of rheumatologists preferred NSAIDs, glucocorticoids, and opioid analgesics, respectively.

Conclusion

The assessment and treatment of chronic pain associated with RA are not standardized. For management, more rheumatologists preferred NSAIDs and glucocorticoids.

Exposure time as an influencing factor among rheumatoid arthritis patients subjected to traditional Siwan therapy

Rheumatoid arthritis (RA) is a long-term autoimmune disease characterized by intra- and extra-articular manifestations. Sand therapy is traditionally indicated for RA, chronic pain, skin diseases, and musculoskeletal disorders. Many places in the world use sand therapy, including Siwa, which is a famous place in Egypt. This study investigated the exposure time to Siwan traditional therapy as a factor influencing central sensitization, pain severity, pain threshold, and kinesiophobia in RA by measuring the central sensory inventory (CSI), visual analogue scale, pressure algometer, and TAMPA kinesiophobia scale, respectively. Twenty-four patients with RA were recruited from 6 traditional healing centers, 24 RA patients were recruited and randomly assigned to 2 equal groups (GI and GII). The first received Siwan traditional therapy for 3 days, while the second received the same program for 5 days. The results revealed a significant difference in CSI between pre- and posttreatment within the GII (P = .038). The Tampa Scale score improved significantly in both groups (P = .004 and P = .014, respectively). Pain severity and pain threshold at all sites showed significant posttreatment improvements in the GII. Significant posttreatment changes were only found for GI in terms of pain severity and the most painful joint (P = .010 and P = .035, respectively). Significant changes were observed in kinesiophobia, pain severity, and pain threshold in the most painful joint 3 and 5 days after Siwan traditional therapy. Despite the nonsignificant differences in all parameters between the 2 groups, all the measured parameters produced favorable results after 5 days of treatment, suggesting the need for a long-term effect investigation.

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.

Examining Rehabilitation Dose in Adults With Rheumatoid Arthritis: Association With Baseline Factors and Change in Clinical Outcomes

OBJECTIVE

To evaluate the association of baseline factors with rehabilitation dose and the association of rehabilitation dose with meaningful change in physical function, pain, and fatigue over 6 months among adults with rheumatoid arthritis (RA).

METHODS

Using data from the National Databank for Rheumatic Diseases registry, we extracted baseline characteristics and self-reported physical function (Health Assessment Questionnaire), pain (visual analog scale [VAS]), fatigue (VAS), rehabilitation dose (low: 1-2 visits, medium: 3-8 visits, high: >8 visits), and follow-up outcomes 6 months later. Changes in clinical outcomes were categorized as improved, no change, or worsened. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) using proportional odds logistic regression models to examine the association of the baseline factors with rehabilitation dose and the association of rehabilitation dose with changes in clinical outcomes, adjusting for potential confounders.

RESULTS

The sample included 1,381 adults with a new episode of rehabilitation (dose: low 27%, medium 42%, high 31%). Worse baseline physical function (adjusted OR 1.29 [95% CI 1.04-1.60]), but not pain (adjusted OR 1.04 [95% CI 0.99-1.10]) or fatigue (adjusted OR 0.98 [95% CI 0.93-1.03]), were associated with a higher rehabilitation dose. A high rehabilitation dose was associated with a favorable change in physical function (OR 1.51 [95% CI 1.14-1.98]), pain (OR 1.44 [95% CI 1.06-1.96]), and fatigue (OR 1.45 [95% CI 1.06-1.99]) compared to a low dose; only the association with physical function change persisted in adjusted models (adjusted OR 1.41 [95% CI 1.03-1.92]).

CONCLUSION

Using real-world data, this study supports a higher rehabilitation dose to improve physical function in adults with RA.

Radiographic damage in early rheumatoid arthritis is associated with increased disability but not with pain-a 5-year follow-up study

OBJECTIVES

To evaluate how radiographic damage, overall and measured as joint space narrowing score (JSNS) and erosion score (ES), as well as other clinical and laboratory measures, relate to disability and pain in early rheumatoid arthritis (RA).

METHODS

An inception cohort of 233 patients with early RA, recruited in 1995-2005, was followed for 5 years. Disability was assessed with the Health Assessment Questionnaire (HAQ), and pain with a visual analogue scale (VAS; 0-100 mm). Radiographs of hands and feet were evaluated using the Sharp-van der Heijde score (SHS), including JSNS and ES. The relation for radiographic scores and other clinical parameters with pain and HAQ were evaluated cross-sectionally by multivariate linear regression analysis and over time using generalized estimating equations.

RESULTS

ES was significantly associated with HAQ cross-sectionally at inclusion, after 2 and after 5 years, and over time. Associations for HAQ with SHS and JSNS were weaker and less consistent compared with those for ES. There was no association between radiographic scores and pain at any visit. Both HAQ and pain were associated with parameters of disease activity. The strongest cross-sectional associations were found for the number of tender joints (adjusted p<0.001 at all visits).

CONCLUSION

Joint damage was associated with disability already in early RA. Erosions of hands and feet appear to have a greater influence on disability compared with joint space narrowing early in the disease. Pain was associated with other factors than joint destruction in early RA, in particular joint tenderness-suggesting an impact of pain sensitization.

Using the derived 28-joint disease activity score patient-reported components (DAS28-P) index as a discriminatory measure of response to disease-modifying anti-rheumatic drug therapy in early rheumatoid arthritis

Background

The 28-joint disease activity score (DAS28) is a widely used measure to assess disease activity in rheumatoid arthritis (RA). The DAS28-P index, a derived proportion of the patient-reported components (joint tenderness and patient global assessment) within the DAS28, has been utilized as a discriminatory measure of non-inflammatory pain mechanisms in RA. This study aimed to evaluate the use of the DAS28-P index as a predictor of treatment response in early RA.

Methods

Patients with early RA enrolled in a supplemental fish oil clinical trial received a combination of disease-modifying anti-rheumatic drugs (DMARDs) according to a ‘treat-to-target’ protocol. First, consecutive measures of the DAS28-P index, derived from the DAS28-erythrocyte sedimentation rate (DAS28-ESR), at each visit over a 1-year period were estimated for each patient. Then, distinct subgroups of treatment responders based on the trajectories of the DAS28-P indices were identified using bivariate k-means cluster analysis. Data on baseline predictors as well as longitudinal outcomes of disease impact and DMARD use over a 1-year period and radiographic progression over a 3-year period were collected and analyzed using a random intercept, population-averaged generalized estimating equation model.

Results

121 patients were included (74% female; mean age of 57; median of 16 weeks of active disease) and a 3-cluster model was identified—the ‘Responders’ group (n = 58; 48%), the ‘Partial Responders’ group (n = 32; 26%), and the ‘Non-Responders’ group (n = 31; 26%). The ‘Partial Responders’ group had consistently higher proportions of the DAS28-P index throughout the study period and had minimal radiographic progression over time, with the lowest joint erosion score of 0.9 [95% confidence interval (CI) 0.2, 1.6], observed at the 3-year follow-up. At 52 weeks, the methotrexate dose was higher for both ‘Partial Responders’ and ‘Non-Responders’ groups (18.5 mg [95% CI 15.5, 21.5] and 18.6 mg [95% CI 15.3, 21.8] respectively), when compared with the ‘Responders’ group (12.8 mg [95% CI 14.7, 20.9]).

Conclusions

Persistently high DAS28-P index scores are useful to distinguish poor patient global assessment and excessive treatment escalation in early RA, suggestive of underlying non-inflammatory pain contributing to higher disease activity score. Early identification of patients with discordant subjective and objective components of composite disease activity measures may allow better tailoring of treatment in RA.

Macrophages and glial cells: Innate immune drivers of inflammatory arthritic pain perception from peripheral joints to the central nervous system

Millions of people suffer from arthritis worldwide, consistently struggling with daily activities due to debilitating pain evoked by this disease. Perhaps the most intensively investigated type of inflammatory arthritis is rheumatoid arthritis (RA), where, despite considerable advances in research and clinical management, gaps regarding the neuroimmune interactions that guide inflammation and chronic pain in this disease remain to be clarified. The pain and inflammation associated with arthritis are not isolated to the joints, and inflammatory mechanisms induced by different immune and glial cells in other tissues may affect the development of chronic pain that results from the disease. This review aims to provide an overview of the state-of-the-art research on the roles that innate immune, and glial cells play in the onset and maintenance of arthritis-associated pain, reviewing nociceptive pathways from the joint through the dorsal root ganglion, spinal circuits, and different structures in the brain. We will focus on the cellular mechanisms related to neuroinflammation and pain, and treatments targeting these mechanisms from the periphery and the CNS. A comprehensive understanding of the role these cells play in peripheral inflammation and initiation of pain and the central pathways in the spinal cord and brain will facilitate identifying new targets and pathways to aide in developing therapeutic strategies to treat joint pain associated with RA.

Lysophosphatidylcholine 16:0 mediates chronic joint pain associated to rheumatic diseases through acid-sensing ion channel 3

ABSTRACT

Rheumatic diseases are often associated to debilitating chronic pain, which remains difficult to treat and requires new therapeutic strategies. We had previously identified lysophosphatidylcholine (LPC) in the synovial fluids from few patients and shown its effect as a positive modulator of acid-sensing ion channel 3 (ASIC3) able to induce acute cutaneous pain in rodents. However, the possible involvement of LPC in chronic joint pain remained completely unknown. Here, we show, from 2 independent cohorts of patients with painful rheumatic diseases, that the synovial fluid levels of LPC are significantly elevated, especially the LPC16:0 species, compared with postmortem control subjects. Moreover, LPC16:0 levels correlated with pain outcomes in a cohort of osteoarthritis patients. However, LPC16:0 do not appear to be the hallmark of a particular joint disease because similar levels are found in the synovial fluids of a second cohort of patients with various rheumatic diseases. The mechanism of action was next explored by developing a pathology-derived rodent model. Intra-articular injections of LPC16:0 is a triggering factor of chronic joint pain in both male and female mice, ultimately leading to persistent pain and anxiety-like behaviors. All these effects are dependent on ASIC3 channels, which drive sufficient peripheral inputs to generate spinal sensitization processes. This study brings evidences from mouse and human supporting a role for LPC16:0 via ASIC3 channels in chronic pain arising from joints, with potential implications for pain management in osteoarthritis and possibly across other rheumatic diseases.

Mindfulness-based stress reduction to improve depression, pain and high patient global assessment in controlled rheumatoid arthritis

Objective

The aim was to improve distressing patient-reported outcomes (PROs) that persisted in RA patients with clinically controlled inflammation (controlled RA).

Methods

In a pragmatic pilot study, we offered mindfulness-based stress reduction (MBSR), a group intervention, to controlled RA patients who had high (≥16) Centre for Evaluation Studies depression (CES-D) scores and/or patient general assessment of disease activity (PGA) at least 2/10 larger than evaluator general assessment (EGA) (PGA-EGA: Delta). Evaluations before, 6 and 12 months after MBSR included CES-D, PGA, modified HAQ, simple disease activity index (SDAI), anxiety (general anxiety disorder 7; GAD-7), coping strategies (coping with health injuries and problems; CHIP), sleep disturbance and pain. Facilitators and obstacles to recruitment and participation were identified. A subset of patients was interviewed for qualitative analysis of their experience.

Results

Out of 306 screened patients, 65 were referred, 39 (60%) agreed and 28 (43%) completed MBSR. Anticipated burden, timing and frequency of group meetings, commuting issues, age extremes and co-morbidities were barriers to participation. Up to 12 months after MBSR, anxiety, depression, emotion-oriented coping, sleep and function significantly improved. Nonetheless, no significant impact was observed on pain, PGA, Delta or SDAI. The interviews revealed that benefits, including integration of effective coping strategies, were maintained.

Conclusion

We addressed MBSR feasibility issues and selection of outcomes in controlled RA patients with distressing PROs. For patients who chose to participate in MBSR, lasting benefits were evident for anxiety, depression, sleep and function. Larger studies are required to evaluate the weaker impact of MBSR on RA-related pain and PGA.

Antibody-induced pain-like behavior and bone erosion: links to subclinical inflammation, osteoclast activity, and acid-sensing ion channel 3-dependent sensitization

ABSTRACT

Several bone conditions, eg, bone cancer, osteoporosis, and rheumatoid arthritis (RA), are associated with a risk of developing persistent pain. Increased osteoclast activity is often the hallmark of these bony pathologies and not only leads to bone remodeling but is also a source of pronociceptive factors that sensitize the bone-innervating nociceptors. Although historically bone loss in RA has been believed to be a consequence of inflammation, both bone erosion and pain can occur years before the symptom onset. Here, we have addressed the disconnection between inflammation, pain, and bone erosion by using a combination of 2 monoclonal antibodies isolated from B cells of patients with RA. We have found that mice injected with B02/B09 monoclonal antibodies (mAbs) developed a long-lasting mechanical hypersensitivity that was accompanied by bone erosion in the absence of joint edema or synovitis. Intriguingly, we have noted a lack of analgesic effect of naproxen and a moderate elevation of few inflammatory factors in the ankle joints suggesting that B02/B09-induced pain-like behavior does not depend on inflammatory processes. By contrast, we found that inhibiting osteoclast activity and acid-sensing ion channel 3 signaling prevented the development of B02/B09-mediated mechanical hypersensitivity. Moreover, we have identified secretory phospholipase A2 and lysophosphatidylcholine 16:0 as critical components of B02/B09-induced pain-like behavior and shown that treatment with a secretory phospholipase A2 inhibitor reversed B02/B09-induced mechanical hypersensitivity and bone erosion. Taken together, our study suggests a potential link between bone erosion and pain in a state of subclinical inflammation and offers a step forward in understanding the mechanisms of bone pain in diseases such as RA.

Achieving pain control in early rheumatoid arthritis with baricitinib monotherapy or in combination with methotrexate versus methotrexate monotherapy

Objectives

This post hoc analysis assessed speed, magnitude and maintenance of pain improvement in patients with early rheumatoid arthritis (RA) receiving baricitinib, baricitinib and methotrexate (MTX), or MTX over 1 year. Cumulative pain and quality of life benefits were also assessed.

Methods

Randomised, double-blind, phase 3 study RA-BEGIN (NCT01711359) compared baricitinib 4 mg (N=159), baricitinib 4 mg +MTX (N=215) and MTX (N=210) in patients with RA who had no or limited prior disease-modifying antirheumatic drug treatment. Pain was assessed on a 0–100 mm Visual Analogue Scale (VAS). Proportion of patients with ≥30%, ≥50% and ≥70% pain improvement from baseline; ≤20 mm and ≤10 mm on the pain VAS; and time to achieve pain improvement thresholds were assessed over 52 weeks, as were Patient Global Assessment (PtGA) and 36-Item Short Form Health Survey Physical Component Score (SF-36 PCS) outcomes.

Results

Baricitinib monotherapy or combination with MTX provides greater (least square mean changes (LSM) from baseline −40 mm and −43 mm, respectively) and more rapid (median 12 and 8 weeks to ≥70% improvement, respectively) pain relief than MTX alone (LSM −31 mm, median 20 weeks to ≥70% improvement) over 52 weeks. Baricitinib, alone or combination, provides 9–10 additional weeks of limited to no pain, similar gain in achievable wellness measured through PtGA, and 5–7 additional weeks with change in SF-36 PCS ≥5 vs MTX over 1 year.

Conclusions

Patients treated with baricitinib reported significantly greater and more rapid pain relief, more weeks with limited to no pain, and clinically meaningful improvements in physical health than patients treated with MTX alone over 1 year.

Unmet Needs in Rheumatoid Arthritis: A Subgroup of Patients With High Levels of Pain, Fatigue, and Psychosocial Distress 3 Years After Diagnosis

Objective

The study objective was to identify subgroups of patients with rheumatoid arthritis (RA) based on their health status 3 years after diagnosis and to assess potential associations to clinical presentation at diagnosis.

Methods

This observational study included patients with RA with 3‐year follow‐up data from the Swedish Epidemiological Investigation of RA study, collected from 2011 to 2018. Hierarchical agglomerative cluster analysis, based on symptoms of pain, fatigue, sleep quality, mood disturbances, and overall health‐related quality of life (HRQoL), was used to identify subgroups 3 years after diagnosis. Modified Poisson regression was used to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for the associations between the subgroups and patient characteristics at diagnosis.

Results

A total of 1055 individuals constituted the study population, of whom 1011 had complete data on the clustering variables and were therefore eligible for analysis (73% women, median age 58 years). The following three clusters were identified: cluster 1 (466 patients with good health status), cluster 2 (398 patients in an intermediate group), and cluster 3 (147 patients with high levels of pain and fatigue together with markedly impaired HRQoL). Cluster 3 was associated to higher baseline pain (RR: 3.71 [95% CI: 2.14‐6.41]), global health (RR: 6.60 [95% CI: 3.53‐12.33]), and the Stanford Health Assessment Questionnaire (RR: 4.40 [95% CI: 2.46‐7.87]), compared with cluster 1 (highest compared with lowest quartiles). An inverse association was seen for baseline swollen joint count (RR: 0.51 [95% CI: 0.34‐0.85]).

Conclusion

A subgroup of patients with RA experience high levels of pain, fatigue, and psychosocial distress 3 years after diagnosis. This subgroup already displayed pronounced pain and functional disabilities at diagnosis.

Pain-like behavior in the collagen antibody-induced arthritis model is regulated by lysophosphatidic acid and activation of satellite glia cells

Inflammatory and neuropathic-like components underlie rheumatoid arthritis (RA)-associated pain, and lysophosphatidic acid (LPA) is linked to both joint inflammation in RA patients and to neuropathic pain. Thus, we investigated a role for LPA signalling using the collagen antibody-induced arthritis (CAIA) model. Pain-like behavior during the inflammatory phase and the late, neuropathic-like phase of CAIA was reversed by a neutralizing antibody generated against LPA and by an LPA_1/3 receptor inhibitor, but joint inflammation was not affected. Autotaxin, an LPA synthesizing enzyme was upregulated in dorsal root ganglia (DRG) neurons during both CAIA phases, but not in joints or spinal cord. Late-phase pronociceptive neurochemical changes in the DRG were blocked in Lpar1 receptor deficient mice and reversed by LPA neutralization. In vitro and in vivo studies indicated that LPA regulates pain-like behavior via the LPA₁ receptor on satellite glia cells (SGCs), which is expressed by both human and mouse SGCs in the DRG. Furthermore, CAIA-induced SGC activity is reversed by phospholipid neutralization and blocked in Lpar1 deficient mice. Our findings suggest that the regulation of CAIA-induced pain-like behavior by LPA signalling is a peripheral event, associated with the DRGs and involving increased pronociceptive activity of SGCs, which in turn act on sensory neurons.

Does wearing arthritis gloves help with hand pain and function? A qualitative study into patients’ views and experiences

Objectives

Arthritis gloves are frequently prescribed to people with undifferentiated inflammatory (UIA) or rheumatoid arthritis (RA), to help reduce hand pain and improve function. Nested within a randomised controlled trial testing the effectiveness of arthritis gloves (Isotoner gloves versuss loose-fitting placebo gloves) in people with RA and UIA, this qualitative study aimed to explore participants’ views on the impact of wearing arthritis gloves on their hand pain and function.

Methods

Semi-structured one-to-one interviews were conducted with purposively selected participants following 12-weeks of glove wear. Participants and the interviewer were blinded to the treatment allocation. Interviews were audio-recorded, transcribed verbatim and analysed using thematic analysis.

Results

Participants (intervention n = 10; control n = 9) recruited from 13 NHS hospital sites in the UK participated in the interviews. Two main themes, with sub-themes, were elicited from the data: (1) Mechanisms determining glove use: ‘As soon as your joints get a bit warmer, the pain actually eases’ (thermal qualities; glove-use in daily activities; glove-use during sleep); and (2) Ambivalence about benefits of arthritis gloves: ‘I suppose a normal pair of gloves would do the same sort of thing?’ (are they a help or hindrance?; aesthetic appeal; future use of gloves).

Conclusion

Participants had ambivalent views on the impact of both the intervention and loose-fitting placebo gloves on their hand pain and function, identifying warmth as the main benefit. Ordinary mid-finger length gloves widely accessible from high street suppliers could deliver warmth and provide perceived benefits to hand pain and function.

Clinical Trial Registration

ISRCTN, ISRCTN25892131; Registered 05/09/2016: retrospectively registered.

Mesenchymal Stem Cell-Based Therapy for Rheumatoid Arthritis

Mesenchymal stem cells (MSCs) have great potential to differentiate into various types of cells, including but not limited to, adipocytes, chondrocytes and osteoblasts. In addition to their progenitor characteristics, MSCs hold unique immunomodulatory properties that provide new opportunities in the treatment of autoimmune diseases, and can serve as a promising tool in stem cell-based therapy. Rheumatoid arthritis (RA) is a chronic systemic autoimmune disorder that deteriorates quality and function of the synovium membrane, resulting in chronic inflammation, pain and progressive cartilage and bone destruction. The mechanism of RA pathogenesis is associated with dysregulation of innate and adaptive immunity. Current conventional treatments by steroid drugs, antirheumatic drugs and biological agents are being applied in clinical practice. However, long-term use of these drugs causes side effects, and some RA patients may acquire resistance to these drugs. In this regard, recently investigated MSC-based therapy is considered as a promising approach in RA treatment. In this study, we review conventional and modern treatment approaches, such as MSC-based therapy through the understanding of the link between MSCs and the innate and adaptive immune systems. Moreover, we discuss recent achievements in preclinical and clinical studies as well as various strategies for the enhancement of MSC immunoregulatory properties.

Effects on health-related quality of life in the randomized, controlled crossover trial ADIRA (Anti-inflammatory Diet In Rheumatoid Arthritis)

Background

Patients with Rheumatoid Arthritis (RA) often report impaired health-related quality of life (HrQoL) such as difficulties in daily life, pain, fatigue and an affected social life. Even when lowering disease activity, pharmacological treatment does not always resolve these factors.

Objective

To investigate if a proposed anti-inflammatory diet improves HrQoL in patients with RA.

Design

In this controlled crossover trial, 50 patients were randomized to start with either an intervention diet (anti-inflammatory) or a control diet (usual Swedish intake) for ten weeks followed by a wash out period before switching to the other diet. Participants received food equivalent to ~1100 kcal/day, five days/week, and instructions to consume similarly for the remaining meals. HrQoL was evaluated using Health Assessment Questionnaire (HAQ), 36-item Short Form Survey (SF-36), Visual Analogue Scales (VAS) for pain, fatigue and morning stiffness, and a time scale for morning stiffness.

Results

Forty-seven participants completed ≥1 diet period and were included in the main analyses. No significant difference between intervention and control diet at end of diet periods was observed for any outcome. However, significant improvements were obtained for SF-36 Physical Functioning (mean:5.79, SE: 2.12, 95% CI: 1.58, 10.01) during the intervention diet period. When excluding participants with anti-rheumatic medication changes, the differences between diet periods increased for most outcomes, favoring the intervention diet period, and the difference for SF-36 Physical Functioning became significant (n = 25, mean:7.90, 95% CI:0.56, 15.24, p = 0.036).

Conclusions

In main analyses, the proposed anti-inflammatory diet did not significantly improve HrQoL for patients with RA compared to control diet. In sub-analyses, significant improvements in physical functioning were detected. Larger studies with consistent medication use and in populations more affected by the disease may be needed to obtain conclusive evidence.

Serum chemerin levels: A potential biomarker of joint inflammation in women with rheumatoid arthritis

Background

Chemerin has a potential role in perpetuating inflammation in autoimmune diseases. Nevertheless, to date, there is no conclusive information on whether high chemerin levels increase the severity of rheumatoid arthritis (RA). Therefore, this study evaluated whether serum chemerin is a biomarker of disease activity in RA patients.

Methods

Study design: cross-sectional. The assessment included clinical and laboratory characteristics, body mass index (BMI) and fat mass. The severity of the disease activity was identified according to the DAS28-CRP index as follows: A) RA with a DAS28-CRP≤2.9 (remission/mild activity) and B) RA with a DAS28-CRP>2.9 (moderate/severe activity). Serum chemerin concentrations were measured by ELISA, and ≥103 ng/mL was considered a high level. Logistic regression analysis was applied to determine whether high chemerin levels were associated with disease activity in RA after adjusting for confounders. Multiple regression analysis was performed to identify variables associated with chemerin levels.

Results

Of 210 RA patients, 89 (42%) subjects had moderate/severe disease activity and had higher serum chemerin levels than patients with low disease activity or remission (86 ± 34 vs 73± 27; p = 0.003). Serum chemerin correlated with the number of swollen joints (r = 0.15; p = 0.03), DAS28-CRP (r = 0.22; p = 0.002), and C-reactive protein levels (r = 0.14; p = 0.04), but no correlation was observed with BMI and fat mass. In the adjusted logistic regression analysis, high chemerin levels (≥103 ng/mL) were associated with an increased risk of moderate/severe disease activity (OR: 2.76, 95% CI 1.35–5.62; p = 0.005). In the multiple regression analysis, after adjusting for potential confounders, serum chemerin levels were associated with higher DAS28-CRP (p = 0.002).

Conclusions

Higher chemerin levels increased the risk of moderate and severe disease activity in RA. These results support the role of chemerin as a marker of inflammation in RA. Follow-up studies will identify if maintaining low chemerin levels can be used as a therapeutic target.

Residual Pain in the Context of Selecting and Switching Biologic Therapy in Inflammatory Rheumatic Diseases

For many years, inflammatory rheumatic diseases (IRDs) represented a source of disappointment in medical care caused by the mediocre efficacy of the available treatments. Some of these diseases, like Rheumatoid Arthritis (RA) or Ankylosing Spondylitis (AS), caused fear in the general population, especially due to associated joint deformities and subsequent disabilities. However, in the last 20 years, a new successful class of antirheumatic drugs has become available: biologic Disease-Modifying Antirheumatic Drugs (bDMARDs). Due to this innovative treatment, the days are over when joint and spine deformities defined the condition of a person with RA or AS. Nonetheless, expectations are higher today, and other clinical problems, (not entirely solved by bDMARDs), seem to drive the drug selection during the span of rheumatic diseases. Most of these issues are covered by the term "unmet needs." One of the most intriguing of such needs is the residual pain (RP) in patients that are otherwise in the biological remission of the disease. Present in a significant proportion of the patients that enter remission status, RP is poorly understood and managed. In recent years, new data has become available in this area and new conceptual clarifications have occurred. In this review, we explain the various nature of RP and the necessity of treatment diversification in such situations. All in all, we believe this condition is far more complex than simple pain and includes other clinical aspects, too (like fatigue or mood changes) so the terms Post-Remission Syndrome (PRS), and PRS pain might be more appropriate.

Pain in rheumatoid arthritis: a seven-year follow-up study of pain distribution and factors associated with transition from and to chronic widespread pain

Objective: To study transitions from and to chronic widespread pain (CWP) over 7 years in patients with rheumatoid arthritis (RA).Method: Two postal questionnaires were sent to patients included in the BARFOT (Better Anti-Rheumatic Pharmacotherapy) study, the first in 2010 and the second in 2017. The questionnaires assessed pain, number of tender and swollen joints, functional disability, health-related quality of life (HRQoL), pharmacological treatment, lifestyle factors, and patient-reported body mass index (BMI). The responders to both questionnaires were divided into three groups according to the reported pain duration and distribution: patients having no chronic pain (NCP), chronic regional pain (CRP), and CWP.Results: In all, 953 patients answered the questionnaires at both time-points. One-third (324) of the patients reported CWP in 2010, and 140 (43%) of the patients had transition to NCP or CRP in 2017. In multivariate logistic regression models, adjusting for age, gender, and disease duration, transition from CWP was associated with normal BMI, fewer tender joints, less pain, less fatigue, fewer pain regions, less disability, better HRQoL, and biologic treatment. In 2010, 628 patients reported NCP or CRP, whereas 114 of them reported CWP in 2017. Transition to CWP was associated with female gender, obesity, more tender and swollen joints, higher pain-related variables, worse disability, and worse HRQoL.Conclusion: There are modifiable factors associated with transitions from and to CWP that could be identified. Paying attention to these factors could improve pain treatment in the management of RA.

Contribution of abnormal BMI to adverse health-related quality of life outcomes after a 52-week therapy in patients with SLE

OBJECTIVES

To investigate whether abnormal BMI is associated with adverse health-related quality of life (HRQoL) outcome, including severe fatigue, after 52 weeks of standard therapy plus belimumab or placebo in patients with SLE.

METHODS

We analysed data from the BLISS-52 (NCT00424476) and BLISS-76 (NCT00410384) trials (n = 1684). Adverse HRQoL was defined as SF-36 scores ≤ the fifth percentile in age- and sex-matched US population-based subjects, and FACIT-F scores <30. We compared BMI groups using the Pearson's χ2 test, and assessed independence with multivariable logistic regression analysis.

RESULTS

Overweight (BMI ≥25 kg/m2) and obese (BMI ≥30 kg/m2) patients showed increased likelihood to exhibit adverse SF-36 physical component summary (OR: 1.8; 95% CI: 1.4, 2.3; P <0.001 and OR: 2.4; 95% CI: 1.8, 3.2; P <0.001, respectively) and FACIT-F (OR: 1.3; 95% CI: 1.1, 1.6; P = 0.010 and OR: 1.5; 95% CI: 1.2, 2.0; P = 0.002, respectively) scores at week 52. Underweight was associated with adverse SF-36 mental component summary scores, also after adjustment for sex, ancestry, age, disease duration, disease activity, organ damage and prednisone dose during the study period (OR: 2.1; 95% CI: 1.2, 3.6; P = 0.007). Addition of belimumab to standard therapy independently protected against adverse SF-36 general health (OR: 0.8; 95% CI: 0.6, 1.0; P = 0.025) and FACIT-F < 30 (OR: 0.8; 95% CI: 0.6, 1.0; P = 0.018).

CONCLUSION

Overweight and obesity contributed to adverse physical and mental HRQoL outcomes after therapeutic intervention in SLE patients, and underweight contributed to adverse mental HRQoL outcome. A protective effect of belimumab against adverse general health and severe fatigue was implicated.

Pain Over Two Years After Start of Biologic Versus Conventional Combination Treatment in Early Rheumatoid Arthritis: Results From a Swedish Randomized Controlled Trial

OBJECTIVE

To compare the pain course between methotrexate (MTX)-refractory early rheumatoid arthritis (RA) patients randomized to infliximab (IFX) versus sulfasalazine (SSZ) plus hydroxychloroquine (HCQ).

METHODS

The randomized, controlled, open-label Swedish Pharmacotherapy (SWEFOT) trial enrolled new-onset RA patients from October 2002 to December 2005. After 3 months of receiving MTX, patients not reaching low disease activity (Disease Activity Score in 28 joints score ≤3.2) were randomized to adding IFX (n = 128) or SSZ plus HCQ (n = 130) and followed for 21 months. Here, outcomes included area under the curve (AUC) for visual analog scale (VAS) scores for pain, unacceptable pain (VAS pain score >40 mm [range 0-100]), and unacceptable pain despite inflammation control (refractory pain; VAS pain score >40 plus C-reactive protein level <10 mg/liter). Between-group differences were analyzed with multivariate regression models.

RESULTS

Overall, 50% of randomized patients (n = 258) in the crude setting reported unacceptable pain at randomization, declining to 29% at 21 months (P < 0.001), when refractory pain constituted 82% of all unacceptable pain. Comparing randomized arms (intent-to-treat analysis), the AUC for VAS pain was lower in the MTX plus IFX group (P = 0.01), and at 21 months, 32% of patients receiving MTX plus IFX and 45% receiving MTX plus SSZ plus HCQ had unacceptable pain (adjusted relative risk 0.68 [95% confidence interval 0.51, 0.90]; P = 0.008). Regarding refractory pain, no between-group differences were observed.

CONCLUSION

Despite active combination treatment, almost one-third of new-onset RA patients reported unacceptable pain after 21 months, and refractory pain constituted more than 4/5 of this pain load. Adding IFX versus SSZ plus HCQ to MTX reduced both cumulative pain and unacceptable pain at 21 months, suggesting less long-term pain for the biologic therapy. These results display insufficient effects of current treatment strategies on inflammation-independent pain components, warranting alternative approaches in affected patients.

Predictors of unacceptable pain with and without low inflammation over 5 years in early rheumatoid arthritis-an inception cohort study

Objectives

Pain is a major symptom in patients with rheumatoid arthritis (RA). In early RA, pain is usually due to synovitis, but can also persist despite effective anti-inflammatory treatment. The objective of this study was to investigate the pain course over time and predictors of unacceptable pain and unacceptable pain with low inflammation, in patients with early RA.

Methods

An inception cohort of 232 patients with early RA, recruited in 1995–2005, was followed in a structured programme for 5 years. Pain was assessed using a visual analogue scale (VAS; 0–100). Unacceptable pain was defined as VAS pain > 40 based on the patient acceptable symptom state (PASS) and low inflammation as CRP < 10 mg/l. Baseline predictors of unacceptable pain were evaluated using logistic regression analysis.

Results

Pain improved significantly during the first 6 months, but then remained basically unchanged. Thirty-four per cent of the patients had unacceptable pain 5 years after inclusion. Baseline predictors of unacceptable pain after 5 years were lower swollen joint counts [odds ratio (OR) 0.71 per standard deviation (95% confidence interval (CI) 0.51–0.99)] and higher VAS for pain and global assessment of disease activity. Unacceptable pain with low inflammation after 5 years was negatively associated with anti-CCP antibodies [OR 0.50 (95% CI 0.22–0.98)].

Conclusion

Over one third of the patients had unacceptable pain 5 years after inclusion. Lower swollen joint count was associated with unacceptable pain at 5 years. The results may be explained by the positive effects of treatment on pain related to inflammation. Non-inflammatory long-lasting pain appears to be a greater problem in anti-CCP-negative patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02550-7.

Adverse Health-Related Quality of Life Outcome Despite Adequate Clinical Response to Treatment in Systemic Lupus Erythematosus

Objective: To determine the prevalence of adverse health-related quality of life (HRQoL) outcomes in patients with SLE who achieved an adequate clinical response after a 52-week long standard therapy plus belimumab or placebo, and identify contributing factors.

Methods: We included patients who met the primary endpoint of the BLISS-52 (NCT00424476) and BLISS-76 (NCT00410384) trials, i.e., SLE Responder Index 4 (total population: N = 760/1,684; placebo: N = 217/562; belimumab 1 mg/kg: N = 258/559; belimumab 10 mg/kg: N = 285/563). Adverse HRQoL outcomes were defined as SF-36 scale scores ≤ the 5th percentile derived from age- and sex-matched population-based norms, and FACIT-Fatigue scores <30. We investigated factors associated with adverse HRQoL outcomes using logistic regression analysis.

Results: We found clinically important diminutions of HRQoL in SLE patients compared with matched norms and high frequencies of adverse HRQoL outcomes, the highest in SF-36 general health (29.1%), followed by FACIT-Fatigue (25.8%) and SF-36 physical functioning (25.4%). Overall, frequencies were higher with increasing age. Black/African American and White/Caucasian patients reported higher frequencies than Asians and Indigenous Americans, while Hispanics experienced adverse HRQoL outcome less frequently than non-Hispanics. Established organ damage was associated with adverse physical but not mental HRQoL outcomes; particularly, damage in the cardiovascular (OR: 2.12; 95% CI: 1.07–4.21; P = 0.032) and musculoskeletal (OR: 1.41; 95% CI: 1.01–1.96; P = 0.041) domains was associated with adverse SF-36 physical component summary. Disease activity showed no impact on HRQoL outcomes. In multivariable logistic regression analysis, addition of belimumab to standard therapy was associated with lower frequencies of adverse SF-36 physical functioning (OR: 0.59; 95% CI: 0.39–0.91; P = 0.016) and FACIT-F (OR: 0.53; 95% CI: 0.34–0.81; P = 0.004).

Conclusions: Despite adequate clinical response to standard therapy plus belimumab or placebo, a substantial proportion of SLE patients still reported adverse HRQoL outcomes. While no impact was documented for disease activity, established organ damage contributed to adverse outcome within physical HRQoL aspects and add-on belimumab was shown to be protective against adverse physical functioning and severe fatigue.

Widespread non-joint pain in early rheumatoid arthritis

Objective: The aim of the study was to assess the development of widespread non-joint pain (WNP) in a cohort of patients with early rheumatoid arthritis (RA), the associated health-related quality of life (HRQoL), and clinical and demographic risk factors for WNP.Method: Incident cases with RA, from the Swedish population-based study Epidemiological Investigation of Rheumatoid Arthritis (EIRA), with a follow-up of at least 3 years, constituted the study population. WNP was defined as pain outside the joints in all four body quadrants and was assessed at the 3 year follow-up. Patients who reported WNP were compared to patients without WNP regarding HRQoL, measured by the Short Form-36, at 3 years, and clinical and demographic characteristics at the time of RA diagnosis.Results: A total of 749 patients constituted the study sample, of whom 25 were excluded after reporting already having severe pain before RA diagnosis. At the 3 year follow-up, 8% of the patients reported having WNP as well as statistically significant worse HRQoL. At the time of RA diagnosis, the patients with WNP had worse pain and pain-related features, while no difference was seen in the inflammatory parameters.Conclusion: WNP occurs in a substantial subset of patients with RA, also early in the course of the disease, and the HRQoL for these patients is significantly reduced. Patients who develop WNP at 3 years are already distinguishable at the time of diagnosis by displaying more pronounced pain ratings together with an average level of inflammatory disease activity.

Machine-learning-based knowledge discovery in rheumatoid arthritis-related registry data to identify predictors of persistent pain

Early detection of patients with chronic diseases at risk of developing persistent pain is clinically desirable for timely initiation of multimodal therapies. Quality follow-up registries may provide the necessary clinical data; however, their design is not focused on a specific research aim, which poses challenges on the data analysis strategy. Here, machine-learning was used to identify early parameters that provide information about a future development of persistent pain in rheumatoid arthritis (RA). Data of 288 patients were queried from a registry based on the Swedish Epidemiological Investigation of RA. Unsupervised data analyses identified the following 3 distinct patient subgroups: low-, median-, and high-persistent pain intensity. Next, supervised machine-learning, implemented as random forests followed by computed ABC analysis-based item categorization, was used to select predictive parameters among 21 different demographic, patient-rated, and objective clinical factors. The selected parameters were used to train machine-learned algorithms to assign patients pain-related subgroups (1000 random resamplings, 2/3 training, and 1/3 test data). Algorithms trained with 3-month data of the patient global assessment and health assessment questionnaire provided pain group assignment at a balanced accuracy of 70%. When restricting the predictors to objective clinical parameters of disease severity, swollen joint count and tender joint count acquired at 3 months provided a balanced accuracy of RA of 59%. Results indicate that machine-learning is suited to extract knowledge from data queried from pain- and disease-related registries. Early functional parameters of RA are informative for the development and degree of persistent pain.

First Validation of the Full PROMIS Pain Interference and Pain Behavior Item Banks in Patients With Rheumatoid Arthritis

OBJECTIVE

Pain interference and pain behavior are highly relevant outcomes in patients with rheumatoid arthritis (RA). The Patient-Reported Outcomes Measurement Information System (PROMIS) is a universally applicable set of item banks measuring patient-reported health, and if applied as computerized adaptive tests (CATs), more efficiently and precisely than current instruments. The objective was to study the psychometric properties of the Dutch-Flemish PROMIS pain interference (PROMIS-PI) and the PROMIS pain behavior (PROMIS-PB) item banks in patients with RA.

METHODS

A total of 2,029 patients with RA completed the full PROMIS-PI (version 1.1, 40 items), and 1,554 patients completed the full PROMIS-PB (version 1.1, 39 items). The following psychometric properties were studied: unidimensionality, local dependence, monotonicity and graded response model (GRM) fit, cross-cultural validity (differential item functioning [DIF] for language [Dutch versus Flemish]), other forms of measurement invariance, construct validity, reliability, and floor and ceiling effects.

RESULTS

The PROMIS-PI and PROMIS-PB banks were sufficiently unidimensional (Omega-hierarchical [Omega-H] 0.99, 0.95, and explained common variance 0.95, 0.78, respectively), had negligible local dependence (0.3-1.4% of item pairs), good monotonicity (H 0.75, 0.46), and a good GRM model fit (no misfitting items). Furthermore, both item banks showed good cross-cultural validity (no DIF for language), measurement invariance (no DIF for age, sex, administration mode, and disease activity), good construct validity (all hypotheses met), high reliability (>0.90 in the range of patients with RA), and an absence of floor and ceiling effects (0% minimum or maximum score, respectively).

CONCLUSION

Both PROMIS-PI and PROMIS-PB banks showed good psychometric properties in patients with RA and can be used as CATs in research and clinical practice.

Physician Prescribing Patterns and Risk of Future Long-Term Opioid Use Among Patients With Rheumatoid Arthritis: A Prospective Observational Cohort Study

OBJECTIVE

To identify the extent to which opioid prescribing rates for patients with rheumatoid arthritis (RA) vary in the US and to determine the implications of baseline opioid prescribing rates on the probability of future long-term opioid use.

METHODS

We identified patients with RA from physicians who contributed ≥10 patients within the first 12 months of participation in the Corrona RA Registry. The baseline opioid prescribing rate was calculated by dividing the number of patients with RA reporting opioid use during the first 12 months by the number of patients with RA providing data that year. To estimate odds ratios (ORs) for long-term opioid use, we used generalized linear mixed models.

RESULTS

During the follow-up period, long-term opioid use was reported by 7.0% (163 of 2,322) of patients of physicians with a very low rate of opioid prescribing (referent) compared to 6.8% (153 of 2,254) of patients of physicians with a low prescribing rate, 12.5% (294 of 2,352) of patients of physicians with a moderate prescribing rate, and 12.7% (307 of 2,409) of patients of physicians with a high prescribing rate. The OR for long-term opioid use after the baseline period was 1.16 (95% confidence interval [95% CI] 0.79-1.70) for patients of low-intensity prescribing physicians, 1.89 (95% CI 1.27-2.82) for patients of moderate-intensity prescribing physicians, and 2.01 (95% CI 1.43-2.83) for patients of high-intensity prescribing physicians, compared to very low-intensity prescribing physicians.

CONCLUSION

Rates of opioid prescriptions vary widely. Our findings indicate that baseline opioid prescribing rates are a strong predictor of whether a patient will become a long-term opioid user in the future, after controlling for patient characteristics.

Association of Pain Centralization and Patient-Reported Pain in Active Rheumatoid Arthritis

OBJECTIVE

Pain is a significant burden for patients with rheumatoid arthritis (RA) despite advancements in treatment. We undertook this study to examine the independent contribution of pain centralization to the pain experience of patients with active RA.

METHODS

A total of 263 RA patients with active disease underwent quantitative sensory testing (QST), including assessment of extraarticular pressure pain thresholds (PPTs), temporal summation (TS), and conditioned pain modulation (CPM). The pain experience was assessed by a pain intensity numeric rating scale and the Patient-Reported Outcomes Measurement Information System pain interference computerized adaptive test. We examined associations between QST measures and pain intensity and pain interference. Multiple linear regression models were adjusted for demographic and clinical variables, including swollen joint count and C-reactive protein level.

RESULTS

Patients with the lowest PPTs (most central dysregulation) reported higher pain intensity than patients with the highest PPTs (adjusted mean difference 1.02 [95% confidence interval (95% CI) 0.37, 1.67]). Patients with the highest TS (most central dysregulation) had higher pain intensity than those with the lowest TS (adjusted mean difference 1.19 [95% CI 0.54, 1.84]). CPM was not associated with differences in pain intensity. PPT and TS were not associated with pain interference. Patients with the lowest CPM (most centrally dysregulated) had lower pain interference than patients with the highest CPM (adjusted mean difference -2.35 [95% CI -4.25, -0.44]).

CONCLUSION

Pain centralization, manifested by low PPTs and high TS, was associated with more intense pain. Clinicians should consider pain centralization as a contributor to pain intensity, independent of inflammation.

Systematic Literature Review of Residual Symptoms and an Unmet Need in Patients With Rheumatoid Arthritis

Objective

To evaluate the nature and burden of residual disease in rheumatoid arthritis (RA) in patients who meet treatment targets. Second, for those who did not meet targets, to evaluate how much is due to patient symptoms.

Methods

Prospective and retrospective studies were searched in Medline, Embase, and Cochrane Library in the English language from January 1, 2008 to April 18, 2018; conference abstracts (from January 2016 to April 2018) and reference lists of relevant studies were also screened.

Results

Of 8,339 records identified, 55 were included in the review; 53 were unique studies, including 10 randomized controlled trials. Of these, 48 reported on patients who achieved low disease activity (LDA) or remission. Studies varied in population, treatment goals, and outcome reporting. The proportions of patients with residual symptoms in these studies varied by the definitions used for LDA or remission and were more often reported in patients with LDA than those in remission. The most commonly reported outcome measures were functional disability (n = 34 studies), tender or swollen joints (n = 18), pain (n = 17), patient global assessment (n = 15), and fatigue (n = 14). However, few studies reported the percentage of patients achieving a specific threshold, which could then be used to easily define the presence of residual symptoms.

Conclusion

Residual symptoms are present in some patients despite their achieving LDA or remission, highlighting an unmet need, especially with respect to improving pain, fatigue, and function. Standardized reporting in future observational studies would facilitate better understanding of this issue in defined RA populations.

Unacceptable pain in the BARFOT inception cohort of patients with rheumatoid arthritis: a long-term study

Objectives: Pain is the most common and troublesome complaint in rheumatoid arthritis (RA). This study aimed to assess the prevalence and clinical implications of unacceptable pain in an inception cohort of patients with RA. Method: This study followed 477 patients from the BARFOT (Better Anti-Rheumatic FarmacOTherapy) early RA cohort for 15 years. Unacceptable pain was defined as ≥ 40 mm on a visual analogue scale for pain, while tolerable pain denoted no pain or pain below this cut-off, according to the patient acceptable symptom state concept. Results: Unacceptable pain was frequent. At the 15 year follow-up visit, 34% had unacceptable pain. Patients with unacceptable pain had, compared with patients with tolerable pain, significantly more disease activity, worse patient global assessment, and worse function on the Health Assessment Questionnaire and Signals of Functional Impairment, but the degree of joint destruction was similar. Disease-modifying anti-rheumatic drug treatment was similar, but patients with unacceptable pain were more often treated with corticosteroids. At 15 years, patients with unacceptable pain who were in remission (33%) had less inflammation and better function than those not in remission, suggesting the presence of non-inflammatory causes of pain. Conclusions: In this cohort of patients with RA, pain was frequent and severe, with negative effects on experienced health and function. Unacceptable pain was frequent and occurred also in patients in remission, indicating that pain in RA is multifactorial and should always be regarded as an important concern in itself. The cause of pain should be recognized and treated appropriately.

Anti-inflammatory Diet In Rheumatoid Arthritis (ADIRA)-a randomized, controlled crossover trial indicating effects on disease activity

BACKGROUND

Many patients with rheumatoid arthritis (RA) report symptom relief from certain foods. Earlier research indicates positive effects of food and food components on clinical outcomes in RA, but insufficient evidence exists to provide specific dietary advice. Food components may interact but studies evaluating combined effects are lacking.

OBJECTIVES

We aimed to investigate if an anti-inflammatory diet reduces disease activity in patients with RA.

METHODS

In this single-blinded crossover trial, 50 patients with RA were randomly assigned to an intervention diet containing a portfolio of suggested anti-inflammatory foods, or a control diet similar to the general dietary intake in Sweden, for 10 wk. After a 4-mo washout period the participants switched diet. Food equivalent to ∼50% of energy requirements was delivered weekly to their homes. For the remaining meals, they were encouraged to consume the same type of foods as the ones provided during each diet. Primary outcome was change in Disease Activity Score in 28 joints-Erythrocyte Sedimentation Rate (DAS28-ESR). Secondary outcomes were changes in the components of DAS28-ESR (tender and swollen joints, ESR, and visual analog scale for general health) and DAS28-C-reactive protein.

RESULTS

In the main analysis, a linear mixed ANCOVA model including the 47 participants completing ≥1 diet period, there was no significant difference in DAS28-ESR between the intervention and control periods (P = 0.116). However, in unadjusted analyses, DAS28-ESR significantly decreased during the intervention period and was significantly lower after the intervention than after the control period in the participants who completed both periods (n = 44; median: 3.05; IQR: 2.41, 3.79 compared with median: 3.27; IQR: 2.69, 4.28; P = 0.04, Wilcoxon's Signed Rank test). No significant differences in the components were observed.

CONCLUSIONS

This trial indicates positive effects of a proposed anti-inflammatory diet on disease activity in patients with RA. Additional studies are required to determine if this diet can cause clinically relevant improvements.This trial was registered at clinicaltrials.gov as NCT02941055.

Defining Pain That Does Not Interfere With Activities Among Rheumatoid Arthritis Patients

OBJECTIVE

The objectives of this study were to: 1) characterize the distribution of noninterfering pain (defined as the pain intensity level at which individuals can function without interference) across different aspects of life among patients with rheumatoid arthritis (RA), and 2) identify clinical characteristics associated with differing levels of noninterfering pain.

METHODS

Patients with RA in FORWARD, The National Databank for Rheumatic Diseases completed 8 items from the Patient-Reported Outcomes Measurement Information System (PROMIS) pain interference item bank that asked about interference with activities. If subjects reported pain interference, they were asked, "At what level would pain no longer interfere with this activity?" on a scale of 0 to 10. Subjects were also asked, "At what level of pain would you be able to do everything you want to do?" Multiple linear regression analyses examined associations between clinical characteristics and noninterfering pain.

RESULTS

A total of 3,949 patients with RA completed the questionnaires. Pain interference was most common for daily activities and least common for ability to concentrate. The mean ± SD level at which pain no longer interfered with activities ranged from 2.7 ± 2.1 for ability to fall/stay asleep to 3.1 ± 2.0 for social activities. Overall, the mean ± SD threshold for noninterfering pain was 2.8 ± 1.9. The mean ± SD level of pain at which patients could do everything they wanted to do was 2.3 ± 1.9. More severe pain intensity was associated with higher noninterfering pain.

CONCLUSION

The mean pain level that did not interfere with activities was 3. High pain intensity was associated with high self-reported noninterfering pain.

Occupational balance and its association with life satisfaction in men and women with rheumatoid arthritis

INTRODUCTION

Despite improved treatments and reduced disability, people with rheumatoid arthritis (RA) experience difficulties in daily life, which may negatively affect their balance of everyday life activities (occupational balance). The aim of this study was to describe occupational balance and its association with self-rated life satisfaction in men and women with RA.

METHODS

A survey, including demographic and health-related questions, was sent to 1,277 people who met the following criteria: with RA >4 years, aged 18-80 years, included in the Swedish Rheumatology Quality Register (SRQ), and had at least one registered visit to the participating rheumatology units in the year before inclusion. The 682 who answered all items in the Occupational Balance Questionnaire (OBQ) were included in the study. Their answers were analysed with descriptive statistics, and logistic regression analyses were conducted on men and women separately.

RESULTS

Significantly higher occupational balance was identified in those participants who were >65 years, had no children at home, had a lower disease activity score, were not continuously stressed and reported low pain intensity. The results of the logistic regression analyses of both genders showed that higher occupational balance was significantly associated with a higher probability for rating themselves as being satisfied with life as a whole.

CONCLUSION

Occupational balance was identified as related to satisfaction with life as a whole, which is valuable information for health professionals. Enhanced occupational balance may be achieved in people with RA by working towards reducing their stress and pain.

Brain Correlates of Continuous Pain in Rheumatoid Arthritis as Measured by Pulsed Arterial Spin Labeling

OBJECTIVE

Central nervous system pathways involving pain modulation shape the pain experience in patients with chronic pain. The aims of this study were to understand the mechanisms underlying pain in patients with rheumatoid arthritis (RA) and to identify brain signals that may serve as imaging markers for developing targeted treatments for RA-related pain.

METHODS

Patients with RA and matched control subjects underwent functional magnetic resonance imaging, using pulsed arterial spin labeling. The imaging conditions included 1) resting state, 2) low-intensity stimulus, and 3) high-intensity stimulus. Stimuli consisted of mechanical pressure applied to metacarpophalangeal (MCP) joints with an automated cuff inflator. The low-intensity stimulus was inflation to 30 mm Hg. The high-intensity stimulus was the amount of pressure required to achieve a pain intensity rating of 40 on a 100-point scale for each RA patient, with the same amount of pressure used in the matched control.

RESULTS

Among RA patients, regional cerebral blood flow (rCBF) in the medial frontal cortex and dorsolateral prefrontal cortex increased during both low-pressure and high-pressure stimulation. No rCBF changes were observed in pain-free controls. Region-of-interest analyses in RA patients showed that baseline rCBF in the medial frontal cortex was negatively correlated with the pressure required for the high-intensity stimulus and positively correlated with pain induced by the low-intensity stimulus. Baseline rCBF was also marginally correlated with disease activity). Regional CBF during high pain was positively correlated with pain severity and pain interference.

CONCLUSION

In response to clinically relevant joint pain evoked by pressure applied to the MCP joint, neural processing in the medial frontal cortex increases and is directly associated with clinical pain in patients with RA.

Altered cerebral pain processing of noxious stimuli from inflamed joints in rheumatoid arthritis: An event-related fMRI study

OBJECTIVE

To our knowledge, this is the first study assessing brain activation in response to painful stimulation over disease-relevant (finger joint) vs. neutral area (thumb nail) in patients suffering from rheumatoid arthritis (RA) compared to healthy controls (HC).

METHOD

Thirty-one RA patients and 23 HC underwent functional magnetic resonance imaging (fMRI) while stimulated with subjectively calibrated painful pressures corresponding to a pain sensation of 50 mm on a 100 mm VAS scale (P50) at disease-affected finger joint and thumbnail (left hand), and corresponding sites in HC.

RESULTS

Compared to controls, RA patients had significantly increased pain sensitivity (lower P50) at the inflamed joints but not at the thumbnail. RA patients exhibited significantly less activation in regions related to pain- and somatosensory processing (S1, M1, anterior insula, S2, SMG and MCC) during painful joint stimulation, compared to HC. No group difference in cerebral pain processing was found for the non-affected thumbnail. Within RA patients, significantly less brain activation was found in response to painful stimulation over disease-affected joint compared to non-affected thumbnail in bilateral S1, bilateral S2, and anterior insula. Further, RA patients exhibited a right-sided dlPFC deactivation, psycho-physiologically interacting (PPI) with the left dlPFC in response to painful stimulation at disease-affected joints.

CONCLUSION

The results indicate normal pain sensitivity and cerebral pain processing in RA for non-affected sites, while the increased sensitivity at inflamed joints indicate peripheral/spinal sensitization. Brain imaging data suggest that disease-relevant pain processing in RA is marked by aberrations and a failed initiation of cortical top-down regulation.

Neuroimmune interactions in chronic pain - An interdisciplinary perspective

It is widely accepted that communication between the nervous and immune systems is involved in the development of chronic pain. At each level of the nervous system, immune cells have been reported to accompany and frequently mediate dysfunction of nociceptive circuitry; however the exact mechanisms are not fully understood. One way to speed up progress in this area is to increase interdisciplinary cross-talk. This review sets out to summarize what pain research has already learnt, or indeed might still learn, from examining peripheral and central nociceptive mechanisms using tools and perspectives from other fields like immunology, inflammation biology or the study of stress.

Risk factors for development and persistence of chronic widespread pain in spondyloarthritis: a population-based two-year follow-up study

Objective: To study chronic widespread pain (CWP) over time in patients with spondyloarthritis (SpA), and to identify risk factors for development and persistence of CWP.Methods: In this cohort study with baseline and 2.5 year follow-up postal surveys, patients with ankylosing spondylitis (AS) and undifferentiated spondyloarthritis (USpA) (47% women) answered questions regarding pain, and were categorized as no chronic pain (NCP), chronic regional pain (CRP), or CWP. For each risk factor candidate (disease duration, body mass index, smoking, and patient-reported outcome measures), logistic regression analyses with CWP as the main outcome were performed separately, together with a basic model including age, gender, and SpA subgroup.Results: Altogether, 644 patients could be categorized at both time-points, yielding similar prevalence estimates at baseline and follow-up, although 38% transitioned between pain groups. Risk factors (odds ratio; 95% confidence interval) for development of CWP included more pain regions (1.36; 1.20‒1.53), higher pain intensity (1.35; 1.20‒1.52), worse fatigue (1.25; 1.13‒1.38), and worse global health (1.35; 1.19‒1.54). Persistent CWP was reported by 72%. In addition to factors predicting development of CWP, higher age (1.02; 1.00‒1.04), female gender (1.82; 1.06‒3.10), and anxiety (1.07; 1.00-1.14) also predicted persistence.Conclusion: The prevalence of CWP remained high over time, but with individual transitions between the pain groups. The development and persistence of CWP were predicted by more pain and worse health, with the addition of female gender and higher age for persistent CWP. Special attention and treatment alternatives for patients with SpA and concomitant CWP are essential in the clinic.