Pain Reports最新文献

[This corrects the article DOI: 10.1097/PR9.0000000000001181.].

Objective: Depressive symptoms and chronic pain commonly co-occur among adolescents and share similar proposed underlying processes, including elevation of proinflammatory cytokines. In this study, we investigate how profiles of 4 commonly measured proinflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α) differ between adolescents with primary chronic pain disorders and pain-free peers. We explored relationships between these cytokines and depressive symptoms, perceived distress (PD), pain severity, functional disability (FD), pain catastrophizing (Pcat), and fear of pain (FOP). Potential mediating effects of cytokines on the relationship between depressive symptoms and FD were also examined.

Methods: Differences in cytokine profiles between groups were compared through t-tests. Relationships between cytokine profiles and outcomes were assessed through partial correlations. Bootstrapping mediation analysis assessed whether cytokines mediated the relationship between depressive symptoms and functional disability. Our sample included 78 youth (chronic pain n = 54, Mage = 14 years; pain-free n = 24; Mage = 16 years).

Results: We found that (1) IL-6 levels were higher among adolescents with chronic pain than pain-free peers; (2) higher IL-1β and IL-6 levels were associated with greater PD among adolescents with and without pain; (3) among the pain group, higher IL-6 levels were associated with greater PD, pain severity, and FD; (4) among the pain group, higher IL-1β levels were associated with greater depressive symptoms, PD, Pcat, and FOP. Mediation effects were not significant.

Conclusion: Our findings suggest that IL-1β and IL-6 play critical roles in the pain experience. Interleukin-6 is more strongly associated with physical symptoms, and IL-1β is more related to fear-avoidance.

Introduction: The central nervous system (CNS) contributes to pain perception across musculoskeletal conditions. The central aspects of pain (CAP) questionnaire captures a single score associated with quantitative sensory testing (QST) evidence of CNS dysfunction validated in knee osteoarthritis.

Objectives: Given the different pathophysiology of rheumatoid arthritis (RA), an inflammatory polyarthritis, this cross-sectional study assessed CAP's psychometric properties and its association with pain in RA.

Methods: Adults with RA were recruited from Nottinghamshire, London, and Cardiff. Participants completed CAP and reported pain using a numerical rating scale. A subgroup underwent additional assessments, including quantitative sensory testing (QST; Pressure Pain detection Threshold, Temporal Summation, Conditioned Pain Modulation), Disease Activity Score-28, C-reactive protein, questionnaires addressing pain and related characteristics, and Central Sensitization Inventory short form (CSI-9). Cronbach alpha, confirmatory factor (CFA), and Rasch measurement theory assessed CAP's reliability and validity. Multivariable linear regression modelled contributions to pain by inflammation indices and CAP or CSI-9.

Results: The 380 participants (73% female, median 63 years) reported average pain over the past 4 weeks of 6/10 and a CAP score of 9/16. Central aspects of pain demonstrated acceptable reliability (ICC_(2,1) = 0.71), CFA fit (comparative fit index = 0.99, Tucker-Lewis index = 0.99, root mean square error of approximation = 0.034, standardized root mean residuals = 0.03), and internal consistency (α = 0.82). Central aspects of pain was significantly associated with pain (0.50 ≤ β ≤ 0.57) but not QST. Central aspects of pain explained 33% of pain variance, rising to 42% with inflammation, age, sex, and body mass index. Central Sensitization Inventory-9 correlated with pain, not QST and explained less pain variance than CAP.

Conclusion: Central aspects of pain is reliable and valid for use with people with RA and explains RA pain variance better than inflammation or CSI-9.

Introduction: Low back pain (LBP) is a leading global factor in disability among older adults. Movement-evoked pain (MEP) is potentially an important mediator in the disability pathway but is predominantly tested in the laboratory.

Objectives: We aimed to explore MEP in the natural environment ("daily" MEP) and its correlation with laboratory MEP, along with potential psychological and immunological influences.

Method: Thirty-five older adults with persistent LBP attended a single laboratory session. Pain catastrophizing, pain-related fear of movement, and pain self-efficacy were measured by questionnaire. Resting inflammation and inflammatory reactivity to painful movement were evaluated using serum interleukin-6, tissue necrosis factor alpha, and C-reactive protein (CRP). Laboratory MEP was defined by aggregate pain intensity with a movement provocation test. Daily MEP was measured for the next 7 days using ecological momentary assessment.

Results: Laboratory MEP was strongly correlated with daily MEP (ρ = 0.780, P = <0.001). C-reactive protein (Hedges [g] = 0.266) and interleukin-6 (g = 0.433) demonstrated small to moderate reactivity to painful movement. After controlling for age and multimorbidity, pain catastrophizing and pain self-efficacy explained 24% to 37% variance in laboratory and daily MEP. Resting inflammatory markers were not associated with MEP; however, C-reactive protein reactivity to painful movement explained 19% to 25% variance in laboratory and daily MEP.

Conclusion: Preliminary indication is that laboratory and daily MEP may be proxy measures for one another, and that MEP is influenced by psychological and immunological factors. Future studies will aim to (1) validate findings among older adults with persistent LBP and (2) for clinical phenotyping, clarify complex relationships among psychological and immunological factors with disability pathway components like MEP.

Introduction: Psychosocial function in people with chronic low back pain (cLBP) is often impaired, indicating poor well-being. Fear-avoidance beliefs (FAB) are common concomitants of cLBP. Fear-avoidance beliefs are gaining attention as a potential prognostic factor for chronification and resulting disability in cLBP. This article aims to examine the associations of back function with FAB.

Methods: This study presents data from a cohort study (DRKS00027907). In the present cross-sectional analyses, we included 914 participants (480 nonchronic LBP [ncLBP], 227 cLBP, 207 asymptomatic). Fear-avoidance beliefs were assessed using the fear-avoidance belief questionnaire (FABQ). The association between the FAB and clinical measures (Ott and Schober test, the sit-to-stand test [STS], and the finger-floor distance [FFD]) were analyzed. Back shape and function were also measured using a noninvasive device. The association between FABQ scores and clinical measures was assessed using age, body mass index, sex, and pain intensity-adjusted multiple linear regression models.

Results: Associations between FAB and both clinical (Ott, Schober, STS, FFD) and noninvasive device measures were small. All relevant clinical measures were attenuated in individuals with elevated FAB.

Discussion: We were able to demonstrate the association of both back shape and function in both clinical tests and noninvasive device measurements with self-reported fear-avoidance beliefs. However, the effect sizes were small. This may be attributed to the different assessment methods (objective vs self-report), resulting in reduced common method variance. In addition to the FAB, there may be other factors (eg, altered neuronal pathways; actual avoidance behavior such as reduced physical activity) that contribute to functional impairment.

Introduction: Ocular pain is a common complaint to eye care providers, associated with a variety of ocular conditions, among which dry eye disease (DED) is affecting millions of people worldwide. Despite being highly prevalent, ocular pain is not managed adequately in the clinic.

Objectives: The aim of this study was to investigate the analgesic potential of neurokinin-1 receptor (NK1R) antagonism in DED.

Methods: Dry eye disease was induced in mice, and an NK1R antagonist L-733,060 was topically administered twice daily throughout the study for 14 days. Hyperalgesia and allodynia were assessed using the eye-wiping test and palpebral ratio measurements. Corneas were collected for measuring substance P (SP) levels by enzyme-linked immunosorbent assay (ELISA) and imaging nerves by immunostaining. Trigeminal ganglions (TG) were collected to determine SP levels by ELISA and transient receptor potential cation channel subfamily V member 1 (TRPV1), transient receptor potential cation channel subfamily M (melastatin) member 8, c-Fos, and activating transcription factor 3 (ATF3) mRNA levels by real-time polymerase chain reaction.

Results: Treating DED mice with L-733,060 resulted in a significant reduction in eye wipe behavior, a significant increase in palpebral ratio, and significant decreases in SP levels in both the cornea and TG compared with the vehicle-treated group. In addition, NK1R antagonist treatment significantly suppressed the upregulation of TRPV1, ATF3, and c-Fos and prevented corneal nerve loss.

Conclusion: Neurokinin-1 receptor antagonism effectively reduced ocular nociception, decreased neuronal activation, and preserved corneal nerves in mice with DED. These findings suggest that blockade of SP signaling pathway is a promising therapeutic strategy for managing DED pain.

Introduction: Alexithymia is elevated in chronic pain and relates to poor pain-related outcomes. However, despite concerns from other clinical populations, the psychometric properties of alexithymia measures have not been rigorously established in chronic pain.

Objective: This study examined the psychometric properties of the Toronto Alexithymia Scale-20 Item (TAS-20) and the Perth Alexithymia Questionnaire (PAQ) in adults with chronic pain.

Methods: An online sample of adults with chronic pain across the United States (N = 1453) completed the TAS-20, PAQ, and related questionnaires at baseline, 3-month follow-up, and 12-month follow-up.

Results: Both measures showed good temporal stability, convergent validity (with emotion regulation scores), divergent validity (with depression and anxiety scores), and criterion validity. Some concerns were raised about the TAS-20: the original 3-factor structure showed a poor model fit; the Externally Oriented Thinking subscale of the TAS-20 had poor factor loadings and unacceptable internal consistency; and, we identified several TAS-20 items that may slightly inflate the predictive validity of the TAS-20 on pain-related outcomes. The original 5-factor structure of the PAQ showed a good fit; each PAQ subscale had good factor loadings and excellent internal consistency.

Conclusions: Both the TAS-20 and PAQ had psychometric strengths. Our data raised some concern for the use of TAS-20 subscales; the PAQ may be a psychometrically stronger option, particularly for investigators interested in alexithymia subscale analysis in people with chronic pain.