Pain and high sensitivity C reactive protein in patients with chronic low back pain and acute sciatic pain

Systemic low-grade C-reactive protein is associated with proximal symptom spread in carpal tunnel syndrome

Introduction

Neuropathic pain is a highly prevalent condition associated with persistent disability. Some patients with neuropathic pain experience symptom spread outside neuroanatomical boundaries; these patients report more severe sensory symptoms and greater disability. However, the mechanisms behind such symptom spread are not fully understood.

Objective

We used pre-surgical carpal tunnel syndrome (CTS) as a human model system of neuropathic pain to identify differences in the concentration of serologic inflammatory mediators between patients with CTS with territorial symptoms and those with proximal symptom spread to either the elbow or shoulder/neck.

Methods

We performed a post-hoc analysis, comparing levels of serologic inflammatory mediators in a discovery cohort among 3 symptoms spread profiles (n = 55; n = 25 no spread, n = 21 spread to elbow, n = 9 spread to shoulder/neck). We then de-novo analysed the significantly dysregulated mediators in an independent validation cohort (n = 72; n = 34 no spread, n = 16 spread to elbow, n = 22 spread to shoulder/neck).

Results

The discovery cohort revealed higher serum concentrations of C-reactive protein (CRP) and interleukin-6 in patients with any symptom spread proximal to the wrist; interferon-γ was higher in patients with symptom spread to the elbow compared with those without proximal spread. The validation study replicated the association of higher CRP concentrations in patients with proximal spread to the elbow (no spread: median [interquartile range] 2.5 [5.4]; spread to elbow 6.2 [4.6]; spread to shoulder/neck 2.6 [3.7], P = 0.006). No other markers replicated in the validation cohort.

Conclusions

Our findings suggest that proximal symptom spread in the context of neuropathic symptoms is associated with low-grade inflammation.

Factors associated with long head of the biceps tendon tear severity and predictive insights for grade II tears in rotator cuff surgery

BACKGROUND

In rotator cuff repair, the long head of the biceps tendon (LHB) is commonly used as graft material. However, factors influencing LHB tear severity are poorly understood, and predicting grade II LHB tears is challenging. This study aimed to identify these factors preoperatively.

METHODS

The demographics, medical parameters, and pain severity of 750 patients who underwent arthroscopic surgery from January 2010 to February 2021 were evaluated to determine the factors associated with LHB tear severity and grade II tears. Both overall and largeto-massive rotator cuff tear (RCT) cohorts underwent ordinal and binary logistic regression analyses. Predictive accuracy for grade II LHB tears was determined using the area under the receiver operating characteristic curve (AUC).

RESULTS

In the overall cohort, high-sensitivity C-reactive protein (hs-CRP) >1 mg/L (P<0.001), subscapularis tear (P<0.001), hypothyroidism (P=0.031), and the tangent sign (P=0.003) were significantly associated with LHB tear severity, and hs-CRP>1 mg/L, subscapularis tear, and Patte retraction degree were significantly associated with grade II LHB tears (P<0.001). In the large-to-massive RCT cohort, hs-CRP>1 mg/L, hypertension, and age ≥50 years (P<0.05) were significantly associated with LHB tear severity, and hs-CRP>1 mg/L (P<0.001) and hypertension (P=0.026) were significantly associated with grade II LHB tears. In both cohorts, hs-CRP >1 mg/L demonstrated good predictive accuracy for grade II LHB tears (AUCs: 0.72 and 0.70).

CONCLUSIONS

Serum hs-CRP >1 mg/L is associated with LHB tear severity and serves as a reliable predictor of grade II LHB tears, facilitating preoperative assessment of the LHB as potential graft material in arthroscopic rotator cuff repair. Level of evidence: III.

Race-specific associations: inflammatory mediators and chronic low back pain

ABSTRACT

Chronic low back pain (cLBP) is a global health crisis that disproportionately burdens non-Hispanic Black (NHB) individuals, compared with those who identify as non-Hispanic White (NHW). Despite the growing personal and societal impact of cLBP, its biological underpinnings remain poorly understood. To elucidate the biological factors that underlie the racial disparities in cLBP, this study sought to determine whether inflammatory mediators associated with pain interference (PI), pain at rest (PAR), and movement-evoked pain (MEP) differ as a function of racial identity. Blood samples were collected from 156 individuals with cLBP (n = 98 NHB participants, n = 58 NHW participants). Enzyme-linked immunosorbent assay and multiplex assays were used to quantify concentrations of proinflammatory (fibrinogen, C-reactive protein [CRP], serum amyloid A, tumor necrosis factor α [TNF-α], and interleukin [IL]-1α, IL-1β, and IL-6) and anti-inflammatory markers (IL-4 and IL-13). Spearman rho correlations were used to assess associations among markers of inflammation and PI, PAR, and MEP using the Brief Pain Inventory-Short Form. Analyses revealed that for NHW patients, CRP, serum amyloid A, and IL-6 were positively associated with cLBP outcomes and IL-4 was inversely associated with PAR and MEP. However, for NHB patients, only IL-1α was positively associated with PAR. Our findings suggest that, while there are associations between inflammation and cLBP outcomes, the biomarkers that underlie the inflammation could very well differ as a function of racialized minority group. However, more research with racially inclusive samples is needed to elucidate the mechanisms that may contribute to racial disparities in cLBP.

Composite Biomarkers, Behavioral Symptoms, and Comorbidities in Axial Low Back Pain: A Systematic Review

PURPOSE

Proinflammatory cytokines play a critical role in chronic inflammation and pain and contribute to behavioral symptoms (depressive symptoms, anxiety, fatigue, sleep disturbance) and comorbidities (diabetes, cardiac diseases, cancer). Evidence is lacking on the specific proinflammatory cytokines associated with these behavioral symptoms/comorbidities co-occurring with axial low back pain (aLBP). This review aimed to systematically analyze the following: (1) specific proinflammatory cytokines associated with aLBP in adults, (2) associations among proinflammatory cytokines and behavioral symptoms in aLBP, and (3) relationships among proinflammatory cytokines and comorbidities in aLBP, to develop a new clinical framework for future diagnostic and intervention targets for patients with aLBP.

METHODS

Electronic databases, including PubMed/MEDLINE, ProQuest Nursing & Allied Health Source, and CINAHL Complete (EBSCO) were searched for the period January 2012 to February 2023. Eligible studies included cross-sectional, case-control, longitudinal, and cohort studies in which proinflammatory cytokines were reported in adults above 18 years with aLBP. Intervention studies and randomized controlled trails were excluded. The Joanna Briggs Institute (JBI) criteria were used for quality evaluation.

RESULTS

Findings from 11 studies showed 3 proinflammatory cytokines associated with pain intensity in adult patients with aLBP: C-Reactive Protein (CRP), Tumor Necrosis Factor (TNF-α), and Interleukin (IL-6). Some studies assessed associations between proinflammatory cytokines and depressive symptoms; none explored the association of proinflammatory cytokines with fatigue, anxiety, sleep disturbance, or comorbidities (diabetes, cardiac diseases, and cancer) in aLBP.

CONCLUSIONS

Proinflammatory cytokines in aLBP can serve as composite biomarkers for pain, associated symptoms, and comorbidities and may serve as a target for future interventions. There is need for well-designed studies assessing associations among chronic inflammation, behavioral symptoms, and comorbidities.

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.

Predicting chronic postsurgical pain: current evidence and a novel program to develop predictive biomarker signatures

ABSTRACT

Chronic pain affects more than 50 million Americans. Treatments remain inadequate, in large part, because the pathophysiological mechanisms underlying the development of chronic pain remain poorly understood. Pain biomarkers could potentially identify and measure biological pathways and phenotypical expressions that are altered by pain, provide insight into biological treatment targets, and help identify at-risk patients who might benefit from early intervention. Biomarkers are used to diagnose, track, and treat other diseases, but no validated clinical biomarkers exist yet for chronic pain. To address this problem, the National Institutes of Health Common Fund launched the Acute to Chronic Pain Signatures (A2CPS) program to evaluate candidate biomarkers, develop them into biosignatures, and discover novel biomarkers for chronification of pain after surgery. This article discusses candidate biomarkers identified by A2CPS for evaluation, including genomic, proteomic, metabolomic, lipidomic, neuroimaging, psychophysical, psychological, and behavioral measures. Acute to Chronic Pain Signatures will provide the most comprehensive investigation of biomarkers for the transition to chronic postsurgical pain undertaken to date. Data and analytic resources generatedby A2CPS will be shared with the scientific community in hopes that other investigators will extract valuable insights beyond A2CPS's initial findings. This article will review the identified biomarkers and rationale for including them, the current state of the science on biomarkers of the transition from acute to chronic pain, gaps in the literature, and how A2CPS will address these gaps.

Assessing the causal relationship between genetically determined inflammatory biomarkers and low back pain risk: a bidirectional two-sample Mendelian randomization study

Background

Observational studies have suggested an association between inflammatory markers and low back pain (LBP), but the causal relationship between these factors remains uncertain.

Methods

We conducted a bidirectional two-sample Mendelian randomization analysis (MR) study to investigate whether there is a causal relationship between inflammatory markers and low back pain. We obtained genetic data for CRP, along with its upstream inflammatory markers IL-6, IL-8, and IL-10, as well as low back pain from publicly available genome-wide association studies (GWAS). We applied several MR methods, including inverse variance weighting, weighted median, MR-Egger, Wald Ratio, and MR-PRESSO, to test for causal relationships. Sensitivity analyses were also conducted to assess the robustness of the results.

Results

Our analyses utilizing the Inverse Variance Weighted (IVW) method, the MR-Egger method, and the weighted median method indicated that IL-6 may be associated with an increased risk of LBP (Effect Size: -0.009, 95% Confidence Interval: -0.013-0.006, p = 9.16e-08); however, in the reverse direction, there was no significant causal effect of LBP on inflammatory markers.

Conclusion

Our study used a Mendelian randomization approach and found that elevated IL-6 levels may reduce the risk of LBP.

Role of C-reactive protein in the bone marrow of Modic type 1 changes

Modic type 1 changes (MC1) are vertebral bone marrow lesions and associate with low back pain. Increased serum C-reactive protein (CRP) has inconsistently been associated with MC1. We aimed to provide evidence for the role of CRP in the tissue pathophysiology of MC1 bone marrow. From 13 MC1 patients undergoing spinal fusion at MC1 levels, vertebral bone marrow aspirates from MC1 and intrapatient control bone marrow were taken. Bone marrow CRP, interleukin (IL)-1, and IL-6 were measured with enzyme-linked immunosorbent assays; lactate dehydrogenase (LDH) was measured with a colorimetric assay. CRP, IL-1, and IL-6 were compared between MC1 and control bone marrow. Bone marrow CRP was correlated with blood CRP and with bone marrow IL-1, IL-6, and LDH. CRP expression by marrow cells was measured with a polymerase chain reaction. Increased CRP in MC1 bone marrow (mean difference: +0.22 mg CRP/g, 95% confidence interval [CI] [-0.04, 0.47], p = 0.088) correlated with blood CRP (r = 0.69, p = 0.018), with bone marrow IL-1β (ρ = 0.52, p = 0.029) and IL-6 (ρ = 0.51, p = 0.031). Marrow cells did not express CRP. Increased LDH in MC1 bone marrow (143.1%, 95% CI [110.7%, 175.4%], p = 0.014) indicated necrosis. A blood CRP threshold of 3.2 mg/L detected with 100% accuracy increased CRP in MC1 bone marrow. In conclusion, the association of CRP with inflammatory and necrotic changes in MC1 bone marrow provides evidence for a pathophysiological role of CRP in MC1 bone marrow.

Prevalence of chronic pain in hemodialysis patients and its correlation with C-reactive protein: a cross-sectional study

End-stage renal disease (ESRD) is a common chronic disease worldwide that requires hemodialysis. Patients may face chronic pain and poor quality of life. Therefore, a better understanding of these variables in hemodialysis patients is essential to provide a good intervention. We aim to determine how common chronic pain is in hemodialysis patients and its correlation with sociodemographics, C-reactive protein (CRP), calcium, phosphorus, albumin, and parathyroid hormone. A cross-sectional study of hemodialysis patients was conducted in Palestine. Data collection took place between November 2020 and May 2021. We used the brief pain inventory score to assess chronic pain, and lab tests detected CRP levels. Data were collected using a convenience sampling technique. There were two hundred sixty-one patients in the present study. The mean age of the patients was 51 years, with 63.6% being men. 47.1% of them reported having chronic pain. Gender (p = 0.011), social status (p = 0.003), educational status (p = 0.010), and number of chronic diseases (p = 0.004) indicated a significant relationship with the severity score of pain. Furthermore, sex (p = 0.011), social status (p = 0.003), and number of chronic diseases (p = 0.002) were significantly associated with the pain interference score. Additionally, Person's test indicated significant correlations between CRP and pain severity (p < 0.001) and with pain interference (p < 0.001). Albumin was significantly and negatively correlated with pain severity (p = 0.001) and pain interference (p < 0.001). Multiple linear regression analysis revealed that patients who had a higher CRP level and many chronic diseases were more likely to have a higher pain severity score. However, pain severity was the only predictor for pain interference. Our results suggest that there is a significant correlation between the existence of chronic pain in hemodialysis patients and increased CRP levels. However, further investigations are needed with a larger number of patients in more than one dialysis unit to confirm this correlation and management of chronic pain in patients with HD.

Monomeric CRP regulates inflammatory responses in human intervertebral disc cells

Aims

CRP is an acute-phase protein that is used as a biomarker to follow severity and progression in infectious and inflammatory diseases. Its pathophysiological mechanisms of action are still poorly defined. CRP in its pentameric form exhibits weak anti-inflammatory activity. The monomeric isoform (mCRP) exerts potent proinflammatory properties in chondrocytes, endothelial cells, and leucocytes. No data exist regarding mCRP effects in human intervertebral disc (IVD) cells. This work aimed to verify the pathophysiological relevance of mCRP in the aetiology and/or progression of IVD degeneration.

Methods

We investigated the effects of mCRP and the signalling pathways that are involved in cultured human primary annulus fibrosus (AF) cells and in the human nucleus pulposus (NP) immortalized cell line HNPSV-1. We determined messenger RNA (mRNA) and protein levels of relevant factors involved in inflammatory responses, by quantitative real-time polymerase chain reaction (RT-qPCR) and western blot. We also studied the presence of mCRP in human AF and NP tissues by immunohistochemistry.

Results

We demonstrated that mCRP increases nitric oxide synthase 2 (NOS2), cyclooxygenase 2 (COX2), matrix metalloproteinase 13 (MMP13), vascular cell adhesion molecule 1 (VCAM1), interleukin (IL)-6, IL-8, and Lipocalin 2 (LCN2) expression in human AF and NP cells. We also showed that nuclear factor-κβ (NF-κβ), extracellular signal-regulated kinase 1/2 (ERK1/2), and phosphoinositide 3-kinase (PI3K) are at play in the intracellular signalling of mCRP. Finally, we demonstrated the presence of mCRP in human AF and NP tissues.

Conclusion

Our results indicate, for the first time, that mCRP can be localized in IVD tissues, where it triggers a proinflammatory and catabolic state in degenerative and healthy IVD cells, and that NF-κβ signalling may be implicated in the mediation of this mCRP-induced state.

Cite this article: Bone Joint Res 2023;12(3):189–198.

Persistent postoperative pain at 1 year after orthopedic surgery and its association with functional disability

PURPOSE

Orthopedic hip, knee, and spinal surgeries have a relatively high incidence of persistent postoperative pain, with the highest risk observed in Asian ethnicity. This study aimed to investigate the distribution of persistent pain at 1 year after surgery and its associated factors and effects on functional disability.

METHODS

This secondary analysis of a prospective observational study included 297 patients aged ≥ 55 years who underwent elective total hip arthroplasty, total knee arthroplasty, and spine and spinal cord surgeries under general anesthesia. Data were collected perioperatively and at 3 months and 1 year postoperatively to assess persistent postoperative pain on a numerical rating scale.

RESULTS

At 1 year postoperatively, 34.6% (103/297) of patients reported pain, with a score of ≥ 1 and a mean score of 1.2. Multivariable negative binomial regression analysis revealed that less preoperative bodily pain (risk ratio [RR], 0.97; 95% confidence interval [CI] 0.94-0.99), preoperative C-reactive protein (CRP) level (RR, 1.19; 95% CI 1.01-1.39), and spine and spinal cord surgeries (RR, 2.48; 95% CI 1.30-4.75) increased the risk of persistent pain at 1 year after surgery, which was a significant factor for predicting the 12-item World Health Organization Disability Assessment Schedule 2.0 score (p < 0.001).

CONCLUSION

The mean score for persistent pain at 1 year after surgery on the numerical rating scale was 1.2. Worse preoperative bodily pain, higher preoperative serum CRP level, and spine and spinal cord surgeries increased the persistent pain score at 1 year after surgery, which was associated with functional disability CLINICAL TRIAL REGISTRATION: This prospective observational study was registered on the University Hospital Medical Information Network (31 December 2015; UMIN000021671).

Evaluation of Bodily Pain Associated with Polycystic Ovary Syndrome: A Review of Health-Related Quality of Life and Potential Risk Factors

Polycystic ovary syndrome (PCOS) is the most common reproductive disease affecting the hormone and metabolic status of women. Its associated symptoms are diverse among the patients, including hyperandrogenism, insulin resistance, anovulation, infertility, obesity, hirsutism, acne, and more. In addition, PCOS can potentially increase the risk of dysmenorrhea, endometriosis, endometrioma, and irritable bowel syndrome, which are highly related to pelvic pain and sexual difficulty. However, little known is whether PCOS exacerbates other chronic bodily pain or contributes to hyperalgesia. Health-related quality of Life (HRQoL) reflects the life satisfaction and quality derived by an individual from mental, physical, emotional, and social activities under specific conditions. In this study, we reviewed pain perception from HRQoL of PCOS patients (SF-36). The review data evidently indicated that pain perception is significantly more prevalent in patients with PCOS than in healthy controls, and obesity and infertile status could be the rationales associated with pain development. Nevertheless, underlying causes remain undetermined due to the limited information from SF-36. Furthermore, we reviewed pathophysiologic factors to pain development or exacerbation, such as the deregulation of inflammation levels, adipokines, and insulin resistance. Although current evidence of pain perception and pathophysiologic risk factors are solid in PCOS, patients' pain perception is often ignored in clinical settings. Clinicians should note the perception and treatment of pain in PCOS patients. The correlation or causality between pain and PCOS warrants further clinical examination and basic studies, thereby providing new insights into this topic in the context of clinical diagnosis and health care.

Comparison of the C-Reactive Protein Level and Visual Analog Scale Scores between Piezosurgery and Rotatory Osteotomy in Mandibular Impacted Third Molar Extraction

This study aimed to compare the C-reactive protein level and visual analog scale scores of piezo- and rotatory-based surgical extraction of the third molar. As a split-mouth study, the comparative groups consisted of 25 patients, each of whom underwent surgical removal of the third molar by piezo on one side and rotatory bur on the other side. C-reactive protein levels were quantitatively assessed (enzyme-linked immunosorbent assay) before and immediately post-extraction. The immediate postoperative blood sample (baseline) C-reactive protein levels were compared with 24 h and 72 h post-op samples, both within and between the groups. Pain was assessed using the visual analog scale at 24 h and 72 h post-operatively. The C-reactive protein levels were lower in the piezo group than in the rotatory group, although the difference was not significant (p > 0.05). The visual analog scale score was significantly (p < 0.01) lower in the piezo group than in the rotatory group. The C-reactive protein levels increased in both the rotary and piezo groups from the pre-op to the immediate post-op value, but in the piezo group, the levels dropped back after 24 h. On the contrary, in the rotatory group, the C-reactive level kept increasing until 24 h; the visual analog scale score dropped significantly from 24 to 72 h for both the rotatory and piezo groups. Surgical techniques that could spare the surrounding soft tissues, such as the piezo, could aid in reducing overall postoperative morbidity.

Multi-Site Observational Study to Assess Biomarkers for Susceptibility or Resilience to Chronic Pain: The Acute to Chronic Pain Signatures (A2CPS) Study Protocol

Chronic pain has become a global health problem contributing to years lived with disability and reduced quality of life. Advances in the clinical management of chronic pain have been limited due to incomplete understanding of the multiple risk factors and molecular mechanisms that contribute to the development of chronic pain. The Acute to Chronic Pain Signatures (A2CPS) Program aims to characterize the predictive nature of biomarkers (brain imaging, high-throughput molecular screening techniques, or "omics," quantitative sensory testing, patient-reported outcome assessments and functional assessments) to identify individuals who will develop chronic pain following surgical intervention. The A2CPS is a multisite observational study investigating biomarkers and collective biosignatures (a combination of several individual biomarkers) that predict susceptibility or resilience to the development of chronic pain following knee arthroplasty and thoracic surgery. This manuscript provides an overview of data collection methods and procedures designed to standardize data collection across multiple clinical sites and institutions. Pain-related biomarkers are evaluated before surgery and up to 3 months after surgery for use as predictors of patient reported outcomes 6 months after surgery. The dataset from this prospective observational study will be available for researchers internal and external to the A2CPS Consortium to advance understanding of the transition from acute to chronic postsurgical pain.

Systemic inflammatory markers in neuropathic pain, nerve injury, and recovery

ABSTRACT

The role that inflammation plays in human nerve injury and neuropathic pain is incompletely understood. Previous studies highlight the role of inflammation in the generation and maintenance of neuropathic pain, but the emerging evidence from the preclinical literature for its role in the resolution of neuropathic pain remains to be explored in humans. Here, we use carpal tunnel syndrome (CTS) as a human model system of nerve injury and neuropathic pain to determine changes in serum cytokine protein levels and gene expression levels before (active stage of disease) and after carpal tunnel decompression surgery (recovery). Fifty-five patients with CTS were studied, and 21 healthy age-matched and gender-matched participants served as controls. In the active stage of the disease (CTS before surgery vs healthy controls), PTGES2 mRNA was decreased in patients (adjusted P = 0.013), while transforming growth factor-β and C-C motif chemokine ligand 5 protein levels were increased (adjusted P = 0.016 and P = 0.047, respectively). In the resolution phase (CTS before surgery vs after surgery), IL-9 mRNA was increased after surgery (adjusted P = 0.014) and expression of IL-6 mRNA and IL-4 protein levels were increased before surgery (adjusted P = 0.034 and P = 0.002, respectively). IL-9 mRNA expression negatively correlated with several (neuropathic) pain scores. By contrast, protein levels of IL-4 positively correlated with pain scores. In conclusion, we demonstrate specific dysregulation of systemic cytokine expression in both the active and resolution phases of nerve injury and neuropathic pain. IL-9 represents an interesting candidate associated with resolution of nerve injury and neuropathic pain.

Shoulder Lesions Do Not Increase Inflammatory Biomarkers in Patients Undergoing Surgery for Glenohumeral Instability: An Exploratory Study

Circulating protein biomarkers have demonstrated utility as a diagnostic tool in predicting musculoskeletal disease severity, but their utility in the evaluation of shoulder lesions associated with shoulder instability is unknown. Thus, the purpose of this exploratory study was to determine whether preoperative biomarkers of cartilage turnover and inflammation are associated with specific shoulder lesions in shoulder instability. Thirty-three patients (29.9 ± 9.4 years of age, 4.5 ± 4.7 dislocations) undergoing surgical treatment for shoulder instability were assessed for the presence or absence of associated shoulder lesions. Biomarkers including cartilage oligomeric matrix protein (COMP), C-reactive protein (HS-CRP), interleukin-8 (IL-8), and macrophage inflammatory protein-1β (MIP-1b) were collected at the time of surgery. Patients with Hill-Sachs lesions had a 31% increase in COMP plasma levels (p=0.046). No other significant differences were observed for COMP, HS-CRP, IL-8, and MIP-1b with any shoulder lesion including Hill-Sachs lesions, capsular injuries, bony Bankart lesions, and SLAP lesions. In conclusion, inflammatory biomarkers including HS-CRP, IL-8, and MIP-1b were not associated with specific shoulder lesions, while biomarkers of cartilage turnover (COMP) were only elevated in Hill-Sachs lesions. These findings suggest that these biomarkers may have limited utility as prognostic indicators in patients with shoulder instability, though large-scale and longitudinal studies are still necessary.

Relationship between systemic inflammation and recovery over 12 months after an acute episode of low back pain

BACKGROUND CONTEXT

Individual characteristics can influence outcomes after injury. Our previous work in individuals with early-acute low back pain (LBP) identified subgroups (clusters) with specific biopsychosocial features that recovered poorly or well by 6 months.

PURPOSE

This study extends on that work by revealing the short- and long-term trajectories of recovery and systemic inflammation of these participant clusters: (1) "inflammatory & poor sleep" (Cluster 1), "high TNF & depression" (Cluster 2), "high pain & high pain-related fear" (Cluster 3), and "low pain & low pain-related fear" (Cluster 4).

STUDY DESIGN/SETTING

Longitudinal cohort study.

PATIENT SAMPLE

Eighty-three individuals within 2 weeks of an acute episode of LBP - grouped into their a priori-defined cluster.

OUTCOME MEASURES

General participant characteristics (sex, age, body mass index, smoking history, previous LBP history); self-reported LBP (0-10 numerical rating scale, LBP-related disability (Roland-Morris Disability Questionnaire), depression (Center for Epidemiological Studies Depression Scale, pain catastrophizing (Pain Catastrophizing Scale), fear avoidance (Fear Avoidance Beliefs Questionnaire), pain self-efficacy (Pain Self-Efficacy Questionnaire), and sleep (Pittsburgh Sleep Quality Index); systemic inflammatory biomarkers (C-reactive protein [CRP], interleukin-6 [IL-6], interleukin-1β, tumor necrosis factor [TNF]).

METHODS

Participants provided blood for the measurement of CRP/cytokines, and completed questionnaires related to their pain/disability, psychological and sleep status. Blood measures were repeated 3-monthly for 9 months, and pain/disability were self-reported fortnightly for 12 months. Recovery (change in pain) and CRP/cytokines were longitudinally compared between clusters using mixed-models. Associations between baseline factors and follow-up CRP/cytokines levels were assessed with multiple regression.

RESULTS

Clusters 1 and 2 were associated, but oppositely, with recovery over the 12-months. Cluster 1 reported most recovery at every 3-monthly interval, whereas Cluster 2 reported least recovery. Cluster 1 had elevated CRP (and IL-6) at baseline that continued to decrease from 3 to 9 months. TNF was elevated early and persistently in Cluster 2. Baseline factors other than inflammation generally failed to predict follow-up inflammation.

CONCLUSIONS

Findings support the early role of CRP (and perhaps IL-6) in control of inflammation and recovery, and a pathological role of persistent TNF overexpression, which may be perpetuated by depressive-like behaviors.

Psychometric validation of the Polish version of the Central Sensitization Inventory in subjects with chronic spinal pain

BACKGROUND

Central sensitization is an amplification of neuronal signaling within the central nervous system. The Central Sensitization Inventory was introduced in 2012. A Polish version of the CSI (CSI-Pol) was developed in 2019, but it was not psychometrically validated. The aim of this study was to validate the CSI-Pol in a sample of Polish-speaking patients with chronic spinal pain and compare them with a group of healthy control subjects.

METHODS

The CSI-Pol was administered to 151 patients with chronic spinal pain recruited from two centers. It was re-administered 7 days later. The psychometric properties were then evaluated, including test-retest reliability, construct validity, factor structure and internal consistency. We correlated the CSI-Pol with functional scales, depression and social support scales and compared CSI-Pol scores in the clinical subjects with 30 healthy control subjects recruited from medical staff and their families.

RESULTS

The CSI-Pol demonstrated excellent internal consistency (Cronbach's α =0,933) and test-retest reliability (Intraclass Correlation Coefficients - ICC =0.96), as well as significant positive associations with other patient-reported scales, including the Neck Disability Index (r = 0.593), Revised Oswestry Low Back Pain Disability Questionnaire (r = 0.422), and other measures of functional and depressive states. An exploratory factor analysis resulted in a 4-factor model. CSI-Pol scores in the clinical sample (35.27 ± 17.25) were significantly higher than the control sample (23.3 ± 8.9).

CONCLUSION

The results of this study suggest that the CSI-Pol may be a useful clinical tool for assessing central sensitization related symptoms and guiding appropriate treatment in Polish-speaking patients with spinal pain.

How Well Do Current Laboratory Biomarkers Inform Clinical Decision-Making in Chronic Pain Management?

OBJECTIVE

Decision-making in chronic pain patients involves a combination of subjective and objective criteria, including patient history, physical examination, imaging, and patient response to prior treatments, clinical experience, probabilities, and recognition of patterns. However, there is a distinct lack of objective laboratory biomarkers in use in routine clinical care. The objective was to review the literature to identify and describe specific biomarkers in chronic pain management.

METHODS

This is a narrative review of the literature regarding the use of laboratory biomarkers in chronic pain. A librarian-assisted literature search of the PubMed, Science Direct, and Google Scholar databases was performed and resulted in 304 possible manuscripts. We included manuscripts assessing laboratory collected biomarkers from urine, serum, cerebrospinal fluid, and saliva. After screening and review of the initial literature search results, a total of 75 manuscripts were included in the narrative review.

CONCLUSION

The studies reviewed suggested that specific biomarkers may help identify those patients at risk of disease development and function as a prognostic indicator for disease progression and treatment response. However, additional research is necessary before specific recommendations can be made, and current clinical decision-making is modified.

Effect of neurogenic acupoint cupping on high sensitive C-reactive protein and pain perception in female chronic pelvic pain: A randomized controlled trial

OBJECTIVES

To determine the effect of neurogenic acupoint dry cupping therapy on high sensitive C-reactive protein (hs-CRP) level, pain perception & intensity, and life impact of pelvic pain in women with chronic pelvic pain (CPP), with regard to the biological and neurophysiological impacts of dry cupping on acupoint.

METHODS

Thirty women with CPP were randomly divided into two equal groups; the study group received dry cupping on neurogenic acupoints plus lifestyle modifications for 8 weeks (n=15), while the control group received only lifestyle modifications for 8 weeks (n=15). Women were assessed pre- and post-rehabilitation program with the hs-CRP blood test, the short-form McGill Pain Questionnaire (SF-MPQ), and the pelvic pain impact questionnaire (PPIQ).

RESULTS

Comparing both groups post-treatment revealed that there were significant reductions in levels of hs-CRP, and scores of SF-MPQ & PPIQ (p<0.05) in the study group compared with the control group. Also, there were significant positive correlations between hs-CRP and both SF-MPQ "Visual Analogue Scale (VAS), Present Pain Intensity (PPI) index & Pain Rating Index (PRI)" and PPIQ (p<0.05).

CONCLUSION

Neurogenic acupoint cupping therapy had significantly improving effects on the degree of inflammation, pain perception & intensity, and life impact of pelvic pain in women with CPP.

Can High-Sensitivity C-Reactive Protein Levels Predict Functional Outcome Following Epidural Steroid Injection in Patients with Lumbar Disc Disease?

Study Design

Prospective cohort study.

Purpose

Inflammatory cytokines produced at the site of disc herniation are considered as pain generators in patients with lumbar disc disease. Whether a high-sensitivity C-reactive protein (hs-CRP) assay can be used in order to predict the quantum of inflammation surrounding nerve roots is a matter of investigation. This study aimed to evaluate the association of hs-CRP level and functional outcomes measured by the Modified Oswestry Low Back Pain Disability Questionnaire (MODY) before and after epidural steroid injection (ESI) in patients with lumbar disc disease.

Overview of Literature

Although many studies examining the role of hs-CRP levels and lumbar pain have been published previously, the results are equivocal, and there is no clear consensus regarding which patients will benefit from an ESI.

Methods

This was a prospective study, with 77 patients in the study group and 23 participants in the control group. Baseline hs-CRP levels were obtained for both groups. Study group patients received a single ESI and were subjected to detailed pre- and post-procedure evaluation using MODY scores. For this group, hs-CRP levels were measured at 1 and 2 months after injection.

Results

Out of 77 patients, 52 had acute and 25 had chronic low back pain. Thirty-six patients with acute pain obtained significant improvement, while 16 had an insignificant response to the ESI. None of the chronic cases had a significant response. The mean baseline hs-CRP (mg/L) among the study group (29.83±10.43) was significantly higher than for the controls (10.26±2.783). The baseline hs-CRP among acute cases, where post ESI MODY score at 2 months had significant reduction, was 32.19±5.126, and those with insignificant reduction was 18.13±7.949 (p<0.001).

Conclusions

Baseline hs-CRP levels can be used to prognosticate the outcome following ESI in patients with acute lumbar disc disease, with radicular pain refractory to physiotherapy and analgesics.

Association of Serum Minerals, Vitamin D, Total Protein, and Inflammatory Mediators and Severity of Low Back Pain

BACKGROUND

Low back pain (LBP) is a multifactorial disorder with multiple etiologies, which are not fully understood. In this study, we aimed to evaluate the relationship between serum levels of minerals, total protein, vitamin D (vit D), and inflammatory mediators with LBP and its severity.

MATERIALS AND METHODS

This case-control study was derived from the study nested in the Fasa Cohort Study. Overall, 148 individuals with LBP were compared with 150 individuals without LBP. Blood samples were evaluated for serum protein, iron (Fe), aluminum (Al), copper (Cu), phosphorus, vit D, IL-1B, IL-6, high-sensitive C-reactive protein (HS-CRP), and TNF-alpha. Severity of pain was measured with the McGill and Oswestry questionnaires.

RESULTS

The mean age of participants in the case and control groups was 49.2 ± 6.1 and 47.57 ± 5.85 years, respectively. In the case group, 61 patients (48.8%) were male. The mean serum levels of Fe, Al, vit D, Cu, IL-1B, IL-6, HS-CRP, and TNF-alpha were significantly different between case and control groups (P≤0.05). However, there were no significant differences between studied groups in the term of sex and serum phosphorus (P>0.05). Regarding pain severity, age was correlated with McGill score (r=0.18), body mass index with Oswestry (r=0.21), Fe with McGill (r=-0.15) and Oswestry (r=-0.13), protein with McGill (r=0.32) and Oswestry (r=-0.32), Al with McGill (r=0.56) and Oswestry (r=0.45), IL-1B with McGill (r=0.19) and Oswestry (r=0.13), TNF-alpha with McGill (r=0.34) and Oswestry (r=0.26), IL-6 with Oswestry (r=0.13), HS-CRP with McGill (r=0.60) and Oswestry (r=0.46), and vit D was correlated with McGill (r=0.21) and Oswestry scores (r=0.17). Higher Fe (odds ratio [OR]: 0.99), protein (OR: 0.47), Al (OR: 0.11), and vit D levels (OR: 0.97) were protective against LBP (P<0.001). Higher IL-1B (OR: 1.01), TNF-alpha (OR: 1.03), and HS-CRP (OR: 1.0003) presented as risk factors for LBP (P<0.001).

CONCLUSION

Our study revealed except phosphorous, all the serum levels minerals and inflammatory markers was significantly different in LBP patients compared to healthy individuals. Also, in the LBP patients, serum levels of Fe, total protein, Al, and vit D aside to inflammatory mediators (i.e., IL-1B, TNF-alpha, and HS-CRP) shows a marked association with severity of LBP.

Is There Any Relationship Between Cervical Disc Herniation and Blood Inflammatory Response?

Objective Inflammation plays an important role in the pathophysiology of disc herniation. The aim of this study was to evaluate blood neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and C-reactive protein (CRP) levels in cervical disc herniation (CDH) patients. Materials and methods We retrospectively analyzed the medical records of 126 patients with neck pain who were treated as inpatients at the Neurosurgery Department of Harran University Faculty of Medicine. The NLR, PLR, and CRP levels during hospital admissions were documented. Results The study included 73 patients with CDH and neck pain, 53 patients with normal cervical MR examination and neck pain, and 50 healthy control subjects. The group with cervical disc hernia had a significantly higher mean serum leucocyte count, neutrophil count, NLR, and CRP level compared to those with a normal MR but neck pain and the control group. NLR was significantly higher in the multi-level CDH group compared to the control group, while the single-level CDH and multi-level CDH had no significant difference with respect to mean serum inflammatory parameters. Conclusion Higher NLR and CRP in patients with CDH compared to patients with neck pain but normal cervical MR and the controls may be due to a developing inflammatory response. It may be speculated that among patients with neck pain, those with non-elevated NLR and CRP levels may have normal neck MR imaging, and in patients with elevated NLR and CRP levels, early protective approaches may play a preventive role in disc degeneration and cervical disc hernia development.

OASIS-a randomised, placebo-controlled trial of oral glucocorticoids for leg pain in patients with acute sciatica: trial protocol

INTRODUCTION

Sciatica is a lower spine condition characterised by radiating leg pain below the knee. It may be accompanied by motor and sensory loss in the distribution of a spinal nerve. There are few effective treatments for sciatica. Orally administered glucocorticoids have shown some promise, however, any beneficial effects need to be confirmed and weighed against drug safety and cost-effectiveness, in a high-quality, definitive trial.

METHODS AND ANALYSIS

The Oral Steroids In Sciatica (OASIS) trial is a randomised, placebo-controlled, double-blind trial that will evaluate a tapering regimen of oral prednisolone in 200 participants with acute sciatica. Participants will be recruited on presentation to general practice, specialist outpatient clinics or hospital emergency departments and randomised to receive orally administered prednisolone 50 mg per day, up to 3 days then tapering to cessation over 10 days, or placebo, for a maximum of 13 days, in addition to guideline advice. Participants will be followed for 1 year. The primary endpoint will be leg pain intensity at 2 weeks. Secondary outcomes will include back pain intensity, disability, time to recovery, quality of life and treatment success rate. Adverse events will be assessed and a cost-effectiveness analysis will be conducted.

ETHICS AND DISSEMINATION

Ethical approval has been granted from the Human Research Ethics Committee, The University of Sydney. Trial results will be disseminated by publications and conference presentations and via the media.

TRIAL REGISTRATION NUMBER

ACTRN12619001716156.

Association Between High-Sensitivity C-Reactive Protein and Idiopathic Adhesive Capsulitis

BACKGROUND

Chronic inflammation is implicated in the development of idiopathic adhesive capsulitis (IAC), whose association with high-sensitivity C-reactive protein (CRP), an inflammation marker, is undetermined. This study's purposes were to investigate the association between high-sensitivity CRP levels and IAC and to determine the metabolic factors associated with high-sensitivity CRP.

METHODS

This case-control study examined a group of 202 patients with IAC and without intrinsic shoulder lesions or extrinsic causes and a control group of 606 age and sex-matched persons seeking general check-ups at our health promotion center during the same period as the case group. Control subjects had normal shoulder function and no previously diagnosed adhesive capsulitis; no medication for diabetes, dyslipidemia, and thyroid abnormalities; and no history of trauma or of shoulder surgery. The studied variables were body mass index; diabetes; thyroid abnormalities; dyslipidemias; triglyceride/high-density lipoprotein (TG/HDL) >3.5; serum levels of thyroid hormone, fasting glucose, and glycosylated hemoglobin A1c (HbA1c); and high-sensitivity CRP >1.0 mg/L. Multivariable conditional logistic regression analysis evaluated the matched sets of subjects. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined for the studied variables possibly affecting IAC.

RESULTS

Serum high-sensitivity CRP >1.0 mg/L was significantly associated with IAC (OR, 2.47 [95% CI, 1.65 to 3.70]) after adjusting for diabetes, fasting glucose level, HbA1c, dyslipidemia, TG/HDL >3.5, and thyroid-stimulating hormone (p ≤ 0.031). Diabetes (OR, 1.71 [95% CI, 1.09 to 3.33]), fasting glucose level (OR, 1.54 [95% CI, 1.12 to 2.12]), HbA1c (OR, 2.00 [95% CI, 1.25 to 3.22]), hypertriglyceridemia (OR, 1.70 [95% CI, 1.03 to 3.41]), hypo-high-density lipoproteinemia (OR, 1.98 [95% CI, 1.04 to 3.79]), and TG/HDL >3.5 (OR, 1.37 [95% CI, 1.06 to 1.88]) were significantly associated with high-sensitivity CRP >1.0 mg/L in patients with IAC (p ≤ 0.039).

CONCLUSIONS

Serum high-sensitivity CRP >1.0 mg/L is an independent associated marker for IAC. Dyslipidemia, insulin resistance, and hyperglycemia, which are recognized factors associated with IAC, are also associated with high-sensitivity CRP >1.0 mg/L in these patients, supporting the interaction of chronic systemic inflammation in IAC.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A systematic review of the role of inflammatory biomarkers in acute, subacute and chronic non-specific low back pain

Background

Low back pain (LBP) is one of the greatest contributors to disability in the world and there is growing interest on the role of biomarkers in LBP. To purpose of this review was to analyze available evidence on the relationship between inflammatory biomarkers, clinical presentation, and outcomes in patients with acute, subacute and chronic non-specific low back pain (NSLBP).

Methods

A search was performed in Medline, Embase, Cinahl and Amed databases. Studies which measured levels of inflammatory biomarkers in participants with NSLBP were included. Two reviewers independently screened titles and abstracts, full-texts, and extracted data from included studies. Methodological quality was assessed using the Newcastle Ottawa Quality Assessment Scale. Level of evidence was assessed using the modified GRADE approach for prognostic studies.

Results

Seven primary studies were included in this review. All results assessed using the modified GRADE demonstrated low to very low quality evidence given the small number of studies and small sample. Three studies examined C-reactive protein (CRP), one of which found significantly higher CRP levels in an acute NSLBP group than in controls and an association between high pain intensity and elevated CRP. Three studies examined tumor necrosis factor alpha (TNF-α), two of which found elevated TNF-α in chronic NSLBP participants compared to controls. Two studies examined interleukin 6 (IL-6), none of which found a significant difference in IL-6 levels between NSLBP groups and controls. Two studies examined interleukin 1 beta (IL-β), none of which found a significant difference in IL-β levels between NSLBP groups and controls.

Conclusions

This review found evidence of elevated CRP in individuals with acute NSLBP and elevated TNF-Α in individuals with chronic NSLBP. There are a limited number of high-quality studies evaluating similar patient groups and similar biomarkers, which limits the conclusion of this review.

Molecular Signature of the Immune Response to Yoga Therapy in Stress-related Chronic Disease Conditions: An Insight

The world Health Organization defines health as complete well-being in terms of physical, mental and social, and not merely the absence of disease. To attain this, individual should adapt and self-mange the social, physical and emotional challenges of life. Exposure to chronic stress due to urbanization, work stress, nuclear family, pollution, unhealthy food habits, lifestyle, accidental death in the family, and natural calamities are the triggering factors, leading to hormonal imbalance and inflammation in the tissue. The relationship between stress and illness is complex; all chronic illnesses such as cardiovascular disease and asthma have their root in chronic stress attributed by inflammation. In recent times, yoga therapy has emerged as an important complementary alternative medicine for many human diseases. Yoga therapy has a positive impact on mind and body; it acts by incorporating appropriate breathing techniques and mindfulness to attain conscious direction of our awareness of the present moment by meditation, which helps achieve harmony between the body and mind. Studies have also demonstrated the important regulatory effects of yoga therapy on brain structure and functions. Despite these advances, the cellular and molecular mechanisms by which yoga therapy renders its beneficial effects are inadequately known. A growing body of evidence suggests that yoga therapy has immunomodulatory effects. However, the precise mechanistic basis has not been addressed empirically. In this review, we have attempted to highlight the effect of yoga therapy on immune system functioning with an aim to identify important immunological signatures that index the effect of yoga therapy. Toward this, we have summarized the available scientific evidence showing positive impacts of yoga therapy. Finally, we have emphasized the efficacy of yoga in improving physical and mental well-being. Yoga has been a part of Indian culture and tradition for long; now, the time has come to scientifically validate this and implement this as an alternative treatment method for stress-related chronic disease.

Comparative efficacy of analgesic gel phonophoresis and ultrasound in the treatment of temporomandibular joint disorders

Aim

The aim of this study is to determine the efficacy of phonophoresis in patients with temporomandibular disorders.

Objective

To prove that phonophoresis could be an effective treatment modality in in patients with temporomandibular disorders.

Procedure

Fifty patients diagnosed clinically and radiographically as temporomandibular disorder were randomly assigned into either of the two groups, namely, (Group A) plain ultrasound and (Group B) phonophoresis. Acoustic gel containing no pharmacological agent was applied in the ultrasound group, whereas a gel containing aceclofenac was applied in the phonophoresis group. Each group was treated three times a week for 2 weeks. The assessment of pain and inflammation both before and after treatment were done using the visual analog scale (VAS) and Creactive protein (CRP).

Results

Intergroup comparison was done and analyzed statistically using independent ttest. Intragroup comparison was done using paired ttest. A significant difference in VAS scores and CRP levels before and after treatment were seen within both ultrasound phonophoresis PH groups. No significant difference was noted statistically between ultrasound and phonophoresis group.

Conclusion

The results of this study suggests that though plain ultrasound as well as phonophoresis with aceclofenac gel are effective in the management of temporomandibular disorders. Phonophoresis was found be slightly superior as evident in VAS scores and CRP levels though not statistically significant.

Association of high sensitivity C-reactive protein with tearing of the long head of the biceps tendon

Background

This study proposed to investigate whether high-sensitivity C-reactive protein (hs-CRP) is an independent risk factor for long head of biceps tendon (LHBT) tear and whether hs-CRP can increase accuracy in diagnosing LHBT tear.

Methods

This study involved 582 shoulders of 557 consecutive patients who received arthroscopic examinations at the authors’ institution between January 2010 and July 2018. The strengths of associations between LHBT tear and various factors were determined by calculating the odds ratios (ORs), with 95% confidence intervals (CIs), using logistic regression analyses. The studied variables were demographic, physical, social, metabolic, comorbidity, hs-CRP, and pain on a visual analog scale (VAS) factors, as well as those related to rotator cuff tear (RCT). Significant factors in the multivariable logistic analysis were evaluated to determine their diagnostic values, including their likelihood ratios and post-test probabilities for LHBT tear.

Results

In the multivariable analysis, five variables were significant: age, retraction degree of Patte, subscapularis tendon tear, hs-CRP > 1 mg/L, and pain VAS (p ≤ 0.01). The best combination of determinations for diagnosing LHBT tear, which yielded a strong positive likelihood ratio of 19.07 and a high post-test probability of 96%, was age ≥ 67 years, subscapularis tendon tear, grade of Patte ≥2, hs-CRP > 1, and pain VAS ≥ 7.

Conclusions

Serum hs-CRP > 1 mg/L is an independent risk factor for LHBT tear, along with the expected risk factors of age, subscapularis tendon tear, retraction degree of Patte, and pain VAS. Serum hs-CRP > 1 mg/L increases the diagnostic accuracy for LHBT tear.

Level of evidence

Level IV, Clinical case series.

The association between insomnia, c-reactive protein, and chronic low back pain: cross-sectional analysis of the HUNT study, Norway

BACKGROUND AND AIMS

Chronic low back pain (chronic LBP) is the number one cause for years lived with disability among 301 diseases and injuries analyzed by The Global Burden of Disease study 2013. Insomnia is highly prevalent among people with chronic LBP. To explain the sleep-pain relationship, theoretical models propose that insomnia symptoms may be associated with increased basal inflammation, operationalized as c-reactive protein (CRP) and lead to further pain and disrupted sleep. We aimed to determine the associations between insomnia, chronic LBP, and inflammation (operationalized as CRP), whilst controlling for age, body mass index, smoking, physical activity, depression, anxiety and osteoarthritis.

METHODS

A cross-sectional analysis of the third Nord-Trøndelag Health Study (2006-2008), a rural population survey of 50,666 participants in Norway aged 20-96 years. Insomnia (dichotomous) was defined according to the Diagnostic and Statistical Manual of Mental Disorders 5th Edition, and chronic LBP (dichotomous) as low back pain or stiffness lasting at least 3 months. Data for CRP were obtained from non-fasting serum samples and assessed via latex immunoassay methodology. We excluded participants with the following self-reported chronic somatic diseases: chronic heart failure, chronic obstructive pulmonary disease, rheumatoid arthritis, fibromyalgia or ankylosing spondylosis. Possible associations between presence of insomnia and presence of chronic LBP (dependent), and the level of CRP and presence of chronic LBP (dependent), were assessed using logistic regression models. The possible association between insomnia and CRP (dependent) was assessed using linear regression. Multivariable analyses were conducted adjusting for confounders stated in our aim that achieved p ≤ 0.2 in univariate regressions. We performed stratified analyses for participants with "Normal" (<3 mg/L) "Elevated" (3-10 mg/L) and "Very High" (>10 mg/L) levels of CRP.

RESULTS

In our total included sample (n = 30,669, median age 52.6, 54% female), 6.1% had insomnia (n = 1,871), 21.4% had chronic LBP (n = 6,559), and 2.4% had both (n = 719). Twenty four thousand two hundred eighty-eight (79%) participants had "Normal" CRP, 5,275 (17%) had "Elevated" CRP, and 1,136 (4%) had "Very High" CRP. For participants with "Normal" levels of CRP, insomnia was associated with higher levels of CRP (adjusted B = 0.04, 95%CI [0.00-0.08], p = 0.046), but not for people with "Elevated" or "Very High" levels of CRP. There was an association between CRP and presence of chronic LBP in the total sample (adjusted OR = 1.01, [1.00-1.01], p = 0.013) and for people with "Normal" CRP (1.05, [1.00-1.10, p = 0.034]. Insomnia was associated with the presence of chronic LBP in the total sample (adjusted OR = 1.99, 95%CI [1.79-2.21], <0.001) and for people with "Normal", "Elevated" and "Very High".

CONCLUSIONS

Individuals with insomnia have twice the odds of reporting chronic LBP. Insomnia, CRP and chronic LBP appear to be linked but the role of CRP appears to be limited. Longitudinal studies may help further explore the causal inference between insomnia chronic LBP, and inflammation.

IMPLICATIONS

Given the strong relationship between insomnia and chronic LBP, screening and management of comorbid insomnia and chronic LBP should be considered in clinical practice. Further longitudinal studies are required to explore whether the presence of insomnia and increased inflammation affects the development of chronic LBP.

Protein Cytokines, Cytokine Gene Polymorphisms, and Potential Acute Coronary Syndrome Symptoms

The purpose of this study was to determine whether relationships exist among protein cytokines, cytokine gene polymorphisms, and symptoms of potential acute coronary syndrome (ACS). Participants included 438 patients presenting to the emergency department (ED) whose symptoms triggered a cardiac evaluation (206 ruled in and 232 ruled out for ACS). Presence or absence of 13 symptoms was recorded upon arrival. Levels of tumor necrosis factor α (TNF-α), interleukin (IL)-6, and IL-18 were measured for all patients. A pilot analysis of 85 patients (ACS = 49; non-ACS = 36) genotyped eight single-nucleotide polymorphisms (SNPs; four TNF and four IL6 SNPs). Logistic regression models were tested to determine whether cytokines or SNPs predicted symptoms. Increased levels of TNF-α and IL-6 were associated with a decreased likelihood of chest discomfort for all patients. Increased levels of IL-6 were associated with a lower likelihood of chest discomfort and chest pressure for ACS patients, and an increased likelihood of shoulder and upper back pain for non-ACS patients. Elevated IL-18 was associated with an increased likelihood of sweating in patients with ACS. Of the four TNF SNPs, three were associated with shortness of breath, lightheadedness, unusual fatigue, and arm pain. In all, protein cytokines and TNF polymorphisms were associated with 11 of 13 symptoms assessed. Future studies are needed to determine the predictive ability of cytokines and related SNPs for a diagnosis of ACS or to determine whether biomarkers can identify patients with specific symptom clusters.

Inflammatory biomarkers in patients with sciatica: a systematic review

BACKGROUND

This systematic review focusses on inflammation as an underlying pathogenic mechanism in sciatica. We addressed two questions in particular: (1) what inflammatory biomarkers have been identified in patients with sciatica in the literature so far? 2) is there an association between the level of inflammatory activity and clinical symptoms?

METHODS

The search was conducted up to December 19th 2018 in MEDLINE, EMBASE, CENTRAL and Web of Science. The study selection criteria: (1) observational cohort studies, cross-sectional studies and randomized clinical trials (RCT), (2) adult population (≥ 18 years) population with sciatica, (3) concentrations of inflammatory biomarkers measured in serum, cerebrospinal fluid (CSF) or biopsies, and (4) evaluation of clinically relevant outcome measures (pain or functional status). Three reviewers independently selected studies and extracted data regarding the study characteristics and the outcomes. Risk of Bias was evaluated using an adjusted version of the Quality in Prognosis Studies (QUIPS) tool.

RESULTS

In total 16 articles fulfilled the criteria for inclusion: 7 cross sectional observational studies and 9 prospective cohort studies that included a total of 1212 patients. With regard to question 1) the following markers were identified: interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-17, IL-21, tumor necrosis factor-α (TNF-α), phospholipase A2, high sensitivity C-reactive protein (hsCRP), C-X-C motif chemokine 5 (CXCM5), CX3CL1, CCL2, epidermal growth factor (EGF), and monocyte chemotactic protein 4 (MCP-4). With regard to question 2) several positive correlations were found in longitudinal studies: a strong positive correlation between inflammatory mediators or byproducts and pain (measured by visual analogue scale, VAS) was found for IL-21 in two studies (r > 0,8), and moderate positive correlations for TNF-a in both serum (r = 0,629) and biopsy (r = 0.65); severe pain (VAS > 4) is associated with increased hsCRP levels among patients with sciatica (adjusted OR = 3.4 (95% CI, 1.1 to 10).

CONCLUSION

In this systematic review there was considerable heterogeneity in the type of biomarkers and in the clinical measurements in the included studies. Taking into account the overall risk of bias of the included studies there is insufficient evidence to draw firm conclusions regarding the relationship between inflammation and clinical symptoms in patients with sciatica.

Discogenic Back Pain: Literature Review of Definition, Diagnosis, and Treatment

Discogenic back pain is multifactorial; hence, physicians often struggle to identify the underlying source of the pain. As a result, discogenic back pain is often hard to treat—even more so when clinical treatment strategies are of questionable efficacy. Based on a broad literature review, our aim was to define discogenic back pain into a series of more specific and interacting pathologies, and to highlight the need to develop novel approaches and treatment strategies for this challenging and unmet clinical need. Discogenic pain involves degenerative changes of the intervertebral disc, including structural defects that result in biomechanical instability and inflammation. These degenerative changes in intervertebral discs closely intersect with the peripheral and central nervous systems to cause nerve sensitization and ingrowth; eventually central sensitization results in a chronic pain condition. Existing imaging modalities are nonspecific to pain symptoms, whereas discography methods that are more specific have known comorbidities based on intervertebral disc puncture and injection. As a result, alternative noninvasive and specific diagnostic methods are needed to better diagnose and identify specific conditions and sources of pain that can be more directly treated. Currently, there are many treatments/interventions for discogenic back pain. Nevertheless, many surgical approaches for discogenic pain have limited efficacy, thus accentuating the need for the development of novel treatments. Regenerative therapies, such as biologics, cell‐based therapy, intervertebral disc repair, and gene‐based therapy, offer the most promise and have many advantages over current therapies. © 2019 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research

Elevated High-Sensitivity C-Reactive Protein And Interleukin-6 Plasma As Risk Factors For Symptomatic Lumbar Osteoarthritis In Postmenopausal Women

AIM

To determine whether elevated high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and erythrocyte sedimentation rate (ESR), as risk factors of symptomatic lumbar osteoarthritis (OA) in estrogen deficiency postmenopausal women.

METHODS

A case-control study was conducted between January and June 2017. The inclusion criteria include post-menopausal women with estrogen deficiency with low back pain. Exclusion criteria were: patients with a history of undergoing bilateral oophorectomy, taking hormonal replacement therapy or corticosteroid, malignancies, and lumbosacral spine trauma. The blood examinations were taken to measure IL-6 level by ELISA, hs-CRP level by spectrophotometry and ESR by modified Westergren method.

RESULTS

A group of 44 pairs of subjects were divided equally into case and control groups showed that in estrogen deficiency postmenopausal women, an increased level of hs-CRP increased the risk for symptomatic lumbar OA (OR = 2.83, CI95% = 1.065-8.776, p = 0.034). Also, a high level of IL-6 increased the risk of symptomatic lumbar OA (OR = 2.7, CI95% = 0.991-8.320, p = 0.033). No such significant findings were found for an increased ESR level.

CONCLUSION

Elevated level of plasma hs-CRP and IL-6 were concluded as risk factors for symptomatic lumbar OA in post-menopausal women.

The association between pro-inflammatory biomarkers and nonspecific low back pain: a systematic review

BACKGROUND CONTEXT

About 85% of the patients with low back pain seeking medical care have nonspecific low back pain (NsLBP), implying that no definitive cause can be identified. Nonspecific low back pain is defined as low back pain and disability which cannot be linked to an underlying pathology, such as cancer, spinal osteomyelitis, fracture, spinal stenosis, cauda equine, ankylosing spondylitis, and visceral-referred pain. Many pain conditions are linked with elevated serum levels of pro-inflammatory biomarkers. Outcomes of interest are NsLBP and the level of pro-inflammatory biomarkers.

PURPOSE

To unravel the etiology and get better insight in the prognosis of NsLBP, the aim of this study was to assess the association between pro-inflammatory biomarkers and the presence and severity of NsLBP.

STUDY DESIGN

A systematic literature search was made in Embase, Medline, Cinahl, Webof-science, and Google scholar up to January 19th 2017.

METHODS

Included were cross-sectional and cohort studies reporting on patients aged over 18 years with NsLBP, in which one or more pro-inflammatory biomarkers were measured in blood plasma. The methodological quality of the included studies was assessed using the Newcastle Ottawa Scale. A best-evidence synthesis was used to summarize the results from the individual studies, meaning that the included studies were ranked according to the consistency of the findings and according to their methodological quality score using the Newcastle Ottawa Scale.

RESULTS

Included were 10 studies which assessed four different pro-inflammatory biomarkers. For the association between the presence of NsLBP and C-reactive protein (CRP), interleukin 6 (IL-6) and tumor necrosis factor (TNF)-α limited, conflicting and moderate evidence, respectively, was found. For the association between the severity of NsLBP and CRP and IL-6, moderate evidence was found. For the association between the severity of NsLBP and TNF-α and RANTES Regulated on Activation, Normal T Cell Expressed and Secreted conflicting and limited evidence, respectively, was found.

CONCLUSIONS

This study found moderate evidence for (i) a positive association between the pro-inflammatory biomarkers CRP and IL-6 and the severity of NsLBP, and (ii) a positive association between TNF-α and the presence of NsLBP. Conflicting and limited evidence was found for the association between TNF-α and Regulated on Activation, Normal T Cell Expressed and Secreted and severity of NsLBP, respectively.

Exploration of the Inter-Relationships Between Obesity, Physical Inactivity, Inflammation, and Low Back Pain

STUDY DESIGN

Retrospective analysis wherein 103 patients were considered, and 76 patients were included: 49 were classified as chronic non-specific low back pain (CNSLBP) (Study group) and 27 had identifiable cases of specific chronic low back pain (LBP) (Control group).

OBJECTIVE

Elucidate markers of systemic inflammation in patients with CNSLBP.

SUMMARY OF BACKGROUND DATA

Mechanisms of LBP are poorly understood. Pro-inflammatory cytokines are increased in obesity and involved with pain modulation; we previously proposed a theoretical model of their mediating role in LBP.

METHODS

Demographic information was acquired via questionnaire, chart review, and blood test data. Univariate analysis identified factors associated with CNSLBP and markers of systemic inflammation. A receiver operating curve and Youden Index were used to select optimal cut-off points for elevated C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Multivariable logistic regression analysis calculated the adjusted strength of relationship between factors that were proposed in our theoretical model for CNSLBP.

RESULTS

Unadjusted CRP was significantly correlated with ESR (R = 0.63, P < 0.0001) and body mass index (BMI) (R = 0.38, P = 0.0015). Physically inactive patients had significantly higher CRP (6.1 vs. 1.2, P = 0.0050). ESR was significantly correlated with number of comorbidities (R = 0.34, P = 0.0047), BMI (R = 0.38, P = 0.0014), and age (R = 0.36, P = 0.0026). Physically inactive patients (10.4 vs. 3.6, P = 0.0001) and females (11.2 vs. 6.4, P = 0.0422) had significantly higher ESR. Adjusted analyses indicated significant relationships between physical inactivity and markers of systemic inflammation (adjusted odds ratios for ESR and CRP: 15.9, P = 0.0380; 15.2, P = 0.0272, respectively), and between elevated CRP and CNSLBP (adjusted odds ratio: 8.0, P = 0.0126).

CONCLUSION

Systemic inflammation may act as a mediator for physical inactivity and obesity in the pathogenesis of CNSLBP.

LEVEL OF EVIDENCE

2.

Low back pain, obesity, and inflammatory markers: exercise as potential treatment

Low back pain is a health issue with significant impact to patients and society. This narrative review aims to synthesize the relationship between obesity, low-grade inflammation and low back pain. It is known that a sedentary lifestyle is a risk factor for obesity and related disorders. The adipose tissue of obese people secretes a range of cytokines of character pro- and anti-inflammatory, with many molecular effects. In addition, pro-inflammatory cytokines are sensitizers of C-reactive protein (CRP), a marker of acute inflammation that can be linked to the musculoskeletal pain sensation individuals with back pain. Another inflammatory marker deserves mention, prostaglandin E2. Prostaglandin E2 is important in the process of triggering actions such as pyrexia, sensation of pain and inflammation, which are exhibited in low back pain condition. The potential for exercises and physical activity to control these mediators and act as a preventative measure for back pain are important because they work as a nonpharmacological strategy to this target audience. There are two types of exercise discussed in this review, the moderate-intensity continuous training and high-intensity interval training.

Inflammatory biomarkers of low back pain and disc degeneration: a review

Biomarkers are biological characteristics that can be used to indicate health or disease. This paper reviews studies on biomarkers of low back pain (LBP) in human subjects. LBP is the leading cause of disability, caused by various spine-related disorders, including intervertebral disc degeneration, disc herniation, spinal stenosis, and facet arthritis. The focus of these studies is inflammatory mediators, because inflammation contributes to the pathogenesis of disc degeneration and associated pain mechanisms. Increasingly, studies suggest that the presence of inflammatory mediators can be measured systemically in the blood. These biomarkers may serve as novel tools for directing patient care. Currently, patient response to treatment is unpredictable with a significant rate of recurrence, and, while surgical treatments may provide anatomical correction and pain relief, they are invasive and costly. The review covers studies performed on populations with specific diagnoses and undefined origins of LBP. Since the natural history of LBP is progressive, the temporal nature of studies is categorized by duration of symptomology/disease. Related studies on changes in biomarkers with treatment are also reviewed. Ultimately, diagnostic biomarkers of LBP and spinal degeneration have the potential to shepherd an era of individualized spine medicine for personalized therapeutics in the treatment of LBP.

Volatility and change in chronic pain severity predict outcomes of treatment for prescription opioid addiction

BACKGROUND AND AIMS

Buprenorphine-naloxone (BUP-NLX) can be used to manage prescription opioid addiction among persons with chronic pain, but post-treatment relapse is common and difficult to predict. This study estimated whether changes in pain over time and pain volatility during BUP-NLX maintenance would predict opioid use during the taper BUP-NLX taper.

DESIGN

Secondary analysis of a multi-site clinical trial for prescription opioid addiction, using data obtained during a 12-week BUP-NLX stabilization and 4-week BUP-NLX taper.

SETTING

Community clinics affiliated with a national clinical trials network in 10 US cities.

PARTICIPANTS

Subjects with chronic pain who entered the BUP-NLX taper phase (n = 125) with enrollment occurring from June 2006 to July 2009 (52% male, 88% Caucasian, 31% married).

MEASUREMENTS

Outcomes were weekly biologically verified and self-reported opioid use from the 4-week taper phase. Predictors were estimates of baseline severity, rate of change and volatility in pain from weekly self-reports during the 12-week maintenance phase.

FINDINGS

Controlling for baseline pain and treatment condition, increased pain [odds ratio (OR) = 2.38, P = 0.02] and greater pain volatility (OR = 2.43, P = 0.04) predicted greater odds of positive opioid urine screen during BUP-NLX taper. Increased pain (IRR = 1.40, P = 0.04) and greater pain volatility [incidence-rate ratio (IRR) = 1.66, P = 0.009] also predicted greater frequency of self-reported opioid use.

CONCLUSIONS

Adults with chronic pain receiving out-patient treatment with buprenorphine-naloxone (BUP-NLX) for prescription opioid addiction have an elevated risk for opioid use when tapering off maintenance treatment. Those with relative persistence in pain over time and greater volatility in pain during treatment are less likely to sustain abstinence during BUP-NLX taper.

Systemic inflammatory profiles and their relationships with demographic, behavioural and clinical features in acute low back pain

Systemic inflammation is linked with development and persistence of many pathological pain states. Although chronic phase inflammatory responses are well reported, the acute phase has received limited attention. Here we investigated circulating pro-inflammatory cytokines and C-reactive protein (CRP), and explored their relationships with symptom severity and other factors in acute low back pain (LBP). Ninety-nine individuals within two weeks of onset of acute LBP and 55 pain-free controls completed questionnaires related to their pain (visual analogue scale, VAS) and disability, behaviour, sleep quality and psychological status. CRP, interleukin-6 (IL-6), tumor necrosis factor (TNF) and interleukin-1β (IL-1β) were measured from serum samples. Biomarkers were compared between LBP and control participants, and in a separate analysis, for those with "high-pain" (VAS ⩾4) and "low-pain" (VAS <4). The relationships between biomarkers and all other variables, including other cytokines/CRP were assessed. CRP was higher in LBP than controls and in those with high- than low-pain (p<0.01). IL-6 was higher in those with high- than low-pain (p<0.05), but not controls. Various pain and non-pain factors were associated with each biomarker differently. These findings suggest systemic CRP and IL-6 are important contributors to inflammation in the early post-onset phase of LBP and that various factors can shape these responses.

Quantitative sensory testing and pain-evoked cytokine reactivity: comparison of patients with sickle cell disease to healthy matched controls

Sickle cell disease (SCD) is an inherited blood disorder associated with significant morbidity, which includes severe episodic pain, and, often, chronic pain. Compared to healthy individuals, patients with SCD report enhanced sensitivity to thermal detection and pain thresholds and have altered inflammatory profiles, yet no studies to date have examined biomarker reactivity after laboratory-induced pain. We sought to examine this relationship in patients with SCD compared to healthy control participants. We completed quantitative sensory testing in 83 patients with SCD and sequential blood sampling in 27 of them, whom we matched (sex, age, race, body mass index, and education) to 27 healthy controls. Surprisingly, few quantitative sensory testing differences emerged between groups. Heat pain tolerance, pressure pain threshold at the trapezius, thumb, and quadriceps, and thermal temporal summation at 45°C differed between groups in the expected direction, whereas conditioned pain modulation and pain ratings to hot water hand immersion were counterintuitive, possibly because of tailoring the water temperature to a perceptual level; patients with SCD received milder temperatures. In the matched subsample, group differences and group-by-time interactions were observed in biomarkers including tumor necrosis factor alpha, interleukin-1ß, interleukin-4, and neuropeptide Y. These findings highlight the utility of laboratory pain testing methods for understanding individual differences in inflammatory cytokines. Our findings suggest amplified pain-evoked proinflammatory cytokine reactivity among patients with SCD relative to carefully matched controls. Future research is warranted to evaluate the impact of enhanced pain-related cytokine response and whether it is predictive of clinical characteristics and the frequency/severity of pain crises in patients with SCD.

Allostatic load and pain severity in older adults: Results from the English Longitudinal Study of Ageing

Pain is common in older adults, is frequently experienced as stressful, and is associated with increased morbidity and mortality. Stress regulatory systems are adaptive to challenge and change, allostasis, until demands exceed the adaptive capacity contributing to dysregulation, resulting in a high allostatic load. A high allostatic load is associated with increased risk of morbidity and mortality. Pain severity, based on the average intensity of frequent pain, was hypothesized to be positively associated with AL. Four formulations of AL were investigated. Cross-sectional data from Wave 4 (2008-2009) of the English Longitudinal Study of Aging (ELSA) were analyzed. Covariates in the model included age, sex, education, smoking status, alcohol consumption, activity level, depression and common comorbid health conditions. A total of 5341 individuals were included; mean age 65.3(±9.2) years, 55% female, 62.4% infrequent or no pain, 12.6% mild pain, 19.1% moderate pain, and 5.9% severe pain. Severe pain was associated with greater AL defined by all four formulations. The amount of variance explained by pain severity and the covariates was highest when allostatic load was defined by the high risk quartile (12.9%) and by the clinical value (11.7%). Findings indicate a positive relationship between pain severity and AL. Further investigation is needed to determine if there is a specific AL signature for pain that differs from other health conditions.

Serum C-reactive protein levels predict regional brain responses to noxious cold stimulation of the hand in chronic whiplash associated disorders

BACKGROUND AND AIMS

Whiplash Associated Disorders (WAD) are a costly health burden. The condition is characterised by sensory disturbances such as widespread hyperalgesia likely indicative of central hyperexcitability. Recently elevated levels of pro-inflammatory biomarkers have also found in acute and chronic WAD. The aim of this cross-sectional study was to investigate the relationship between inflammatory biomarkers and pain processing in people with persistent whiplash associated disorders (WAD).

METHODS

Twenty one participants with chronic whiplash (>3 months) were recruited. Venous blood samples were collected and assays performed for C-reactive protein (CRP) and TNF-α. Blood oxygen level-dependent (BOLD) contrast images of the brain were acquired with a Siemens 1.5T MRI scanner during repeated 24s stimulus blocks of innocuous or painful stimuli (thumbnail pressure and cold stimulation of dorsum of hand) separated by 36s inter-stimulus intervals. Stimulus intensities used during scanning were at the level of participants' thresholds for moderate pain. Parameter estimates representing BOLD signal increases during painful events from each participant were tested for associations with inflammatory biomarkers.

RESULTS

Clinically relevant levels of CRP and TNF-α were found in 33% and 38% of participants. Levels of CRP showed a positive correlation with levels of cold pain activation in brain regions including the anterior insula, posterior parietal cortex, caudate and thalamus (p_corrected<0.05). Levels of TNF-α were not related to activation levels during either noxious pressure or cold. Pressure pain activations also did not show a relationship with CRP levels.

CONCLUSIONS

Shared variance between inflammation and increased levels of regional pain-related activation in people with persistent whiplash symptoms is apparent for cold, but not pressure stimuli.

IMPLICATIONS

The results highlight cold pain processing as an important aspect of whiplash chronicity, although the implications of this modality-specific effect are not readily apparent.

Age differences in cytokine expression under conditions of health using experimental pain models

Older adults are at an increased risk to develop frequent and prolonged pain. Emerging evidence proposes a link between immune changes and pain, which is consistent with the inflammation theory of aging and the increased incidence of age-related diseases. This study tested the hypothesis that older adults show greater immune responses to experimental pain compared to younger individuals. Study subjects (8 younger and 9 older healthy adults) underwent 3 experimental sessions using well-validated human experimental pain models: the cold pressor task (CPT), focal heat pain (FHP), and a non-painful thermal control. Blood was collected through an indwelling catheter at baseline and 3, 15, 30, 45, 60, and 90 min post-stimuli administration. Pro-inflammatory cytokines (TNF-α IL-6 and IL-8) peaked at the same time points for both groups, with greater elevations among older subjects for TNF-α and IL-8 in both pain models and elevations in IL-6 only for CPT. Anti-inflammatory cytokines (IL-4, IL-5, and IL-10) generally peaked later for the older subjects, with increased elevations for FHP but not the CPT. These data are consistent with the assertion that age-related immune system dysregulation may account for the increased prevalence of pain in older adults.

Markers of inflammation and fibrinolysis in relation to outcome after surgery for lumbar disc herniation. A prospective study on 177 patients

PURPOSE

The role of inflammation and fibrinolysis for the development of back pain and sciatica has been discussed. The aim of this study was to assess the relationship between markers of inflammation and fibrinolysis, to predict the outcome after surgery for lumbar disc herniation.

METHODS

177 patients were recruited. High sensitive C-reactive protein (hsCRP), plasminogen activator inhibitor 1 (PAI-1), fibrinogen, and D-dimer were analyzed preoperatively. Visual analogue scale (VAS) for back and leg pain, Oswestry Disability Index (ODI), and EuroQol 5 Dimensions (EQ-5D) were assessed preoperatively and at 6 weeks, 6-, 12-, and 24- months postoperatively. Dichotomization was made at the median for the laboratory analyses, and between the worst quartile and the other three quartiles for the outcome variables. Logistic regression was used to determine the odds ratios (OR) and 95 % confidence intervals (CI).

RESULTS

The associations between PAI-1 and outcome seemed to be most prominent at the 6 and 12-month follow-up. When being in the upper half of PAI-1, the OR for being in the worst quartile of VAS back pain 12 months postoperatively was 3.33 (1.56-7.10). The corresponding OR for VAS leg pain was 2.46 (1.18-5.10), for ODI 2.83 (1.35-5.94) and for EQ-5D 2.73 (1.30-5.75). The OR for hsCRP was 2.10 (1.03-4.29) for being in the worst quartile of VAS back pain. Fibrinogen or D-dimer was not associated with any outcome variable.

CONCLUSIONS

High PAI-1, a marker of fibrinolysis, was fairly consistently associated with poor outcome, while hsCRP, fibrinogen, and D-dimer were not.

Increased insomnia symptoms predict the onset of back pain among employed adults

Background

Back pain is among the most prevalent pain disorders causing chronic disability among adults, and insomnia is a common co-morbidity. However, whether insomnia precedes back pain or vice versa remains unclear. The current study tested the temporal association between insomnia and back pain.

Methods

A longitudinal design was used to investigate whether changes in insomnia over time predict the onset of back pain and vice versa. The study was conducted on a cohort of active healthy working adults (N = 2,131, 34% women) at three time points (T1, T2, and T3) over a period of 3.7 years (range = 2.2–5.12) years. Logistic regression analysis was used to test whether increased insomnia symptoms from T1 to T2 predicted the onset of new back pain. Ordinary least squares regression was used to test whether the existence of back pain at T2 predicted an increase in insomnia from T2 to T3.

Results

The results indicated that after controlling for socioeconomic variables, self-reported health, lifestyle behaviors, and anthropometrics, a T1–T2 increase in insomnia symptoms was associated with a 1.40-fold increased risk of back pain at T3 (OR = 1.40; 95% CI = 1.10–1.71). No support was found for reverse causation; i.e., that back pain predicts subsequent increase in insomnia.

Conclusions

Insomnia appears to be a risk factor in the development of back pain in healthy individuals. However, no evidence of reverse causation was found.

Assessment of Vitamin D status In Patients of Chronic Low Back Pain of Unknown Etiology

Low back pain is very disabling and dispiriting because of the physical impediment it causes and its psychological effects. Innumerable factors have been implicated in its etiology. In spite of improvements in diagnostic modalities, a considerable number of such cases fall in the ambiguous zone of unknown etiology or 'idiopathic.'Early diagnosis of low back pain will allow effective prevention and treatment to be offered. This study was conducted to assess the contribution of vitamin D levels and other biochemical factors to chronic low back pain in such cases. All patients attending the orthopedics OPD for low back pain in whom a precise anatomical cause could not be localized, were prospectively enrolled in this study. We measured serum levels of glucose, calcium, phosphorus, uric acid, rheumatoid factor, C reactive protein, alkaline phosphatase, total protein, albumin and 25 (OH) D concentrations in 200 cases and 200 control samples. The patients showed significantly lower vitamin D levels compared to controls with p value < 0.0001. The maximum number of low back pain patients were in the age group of 31-50 years (42 %).The average BMI was 23.27 ± 5.17 kg/sq m, 73 % of total patient population were females and 27 % were known case of type 2 diabetes mellitus. Calcium, alkaline phosphatase, was positively correlated with vitamin D and glucose showed a negative correlation with vitamin D in the patient population. The problem of low back pain provides a challenge to health care providers. The problem in developing countries is compounded by ignorance to report for early treatment and occupational compulsions in rural areas and sedentary lifestyle in urban youth. The authors strongly recommend early frequent screening for vitamin D along with glucose, protein, albumin, calcium, phosphorus, CRP as part of general health checkup for non-specific body pain, especially low back pain.

The association of pain with protein inflammatory biomarkers: a review of the literature

BACKGROUND

Pain is a key diagnostic criterion in many medical conditions. In the absence of self-reported pain, measurement of a proxy for pain, such as an inflammatory biomarker, could aid in diagnosis and disease management.

OBJECTIVES

The aim was to determine if there is an association between inflammatory biomarkers and self-reported pain in individuals with medical conditions associated with the symptom of pain and to clarify whether inflammatory biomarkers might aid in the diagnostic process.

METHODS

An integrative literature review was conducted. PubMed, CINAHL, and Cochrane databases were searched for articles published between January 2000 and September 2012. Inclusion criteria were original research testing a relationship between inflammatory biomarkers and pain, pain measurement, laboratory measure of inflammatory biomarkers, and a prospective single-group experimental design or comparative nonrandomized or randomized design. Excluded were studies describing an association between inflammatory biomarkers and treatment, risk, and generation; pathophysiology; or genetic polymorphisms/transcripts. Ten studies meeting inclusion criteria were reviewed.

RESULTS

In most of the studies, baseline elevations in both proinflammatory and anti-inflammatory cytokines were reported in painful conditions compared with healthy controls. In half of the studies, higher levels of proinflammatory markers (C-reactive protein, tumor necrosis factor-alpha, interleukin-2 [IL-2], IL-6, IL-8, IL-10, and CD40 ligand) were associated with greater pain. Proinflammatory cytokines decreased after treatment for pain in only two studies.

DISCUSSION

The association between inflammatory markers varied in the direction and magnitude of expression, which may be explained by differences in designs and assays, disease condition and duration, variations in symptom severity, and timing of measurement. Elevation in anti-inflammatory cytokines in the presence of pain represents a homeostatic immune response. Further study is required to determine the value of cytokines as biomarkers of pain.