Is blood neutrophil-lymphocyte ratio an independent predictor of knee osteoarthritis severity?

Older age at anterior cruciate ligament reconstruction associates with a lower systemic inflammation response index after surgery

Purpose

The purpose of this study was to investigate the association of age at anterior cruciate ligament reconstruction (ACLR) with systemic indices of the immune system and inflammation after surgery.

Methods

This study consisted of a retrospective, cohort design. Patients (male and female, ≥18 years) that underwent ACLR at a single academic institution and with complete blood cell (CBC) count data obtained ≥ 1-year after surgery were included. Patients with a documented diagnosis of knee osteoarthritis (OA) before ACLR were excluded, while those with a documented diagnosis of knee OA after ACLR were included in this study. The systemic inflammation response index (SIRI), systemic immune-inflammatory index (SII), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) were calculated from the CBC data. Patients (n = 198) were separated into groups based on age at ACLR: (1) 18-29 y (n = 96), (2) 30-39 y (n = 50), or (3) ≥40 y (n = 52).

Results

Subject characteristics (patient sex, height, body mass, and body mass index), follow-up interval, time from ACLR to CBC assessment, and concomitant procedures performed at ACLR were not significantly different between age groups. The PLR, NLR, MLR, and SII were not significantly different between groups, while the SIRI was significantly lower in the 30-39 (p < 0.01) and ≥40 y (p < 0.01) groups compared to the 18-29 y group. An older age at ACLR (i.e., 30-39 y and ≥40 y) was associated with an increased occurrence (11.5 and 12 %, respectively) of a knee OA diagnosis following surgery compared to that in the younger age group (18-29 y, 1.0 %; p = 0.04).

Conclusion

We conclude that an older age at ACLR associated with a lower systemic inflammatory response index at a minimum of 1-year following surger.

Level of evidence

Level III.

Role of neutrophil to lymphocyte ratio in osteoarthritis: A systematic review and meta-analysis

BACKGROUND

Osteoarthritis (OA) involves low-grade inflammation. The neutrophil-to-lymphocyte ratio (NLR) may serve as a simple biomarker, but its role in OA remains unclear.

AIM

To review the existing scientific literature on the role of NLR in OA, a classic age-related disorder, to perform a meta-analysis of the available data.

METHODS

The electronic databases PubMed, ProQuest, and Scopus were systematically searched from inception to March 1, 2024. The inclusion criteria were retrospective and prospective case-control studies involving human subjects with OA and healthy controls. The included studies needed to provide NLR levels for both OA patients and healthy controls and perform a comparative analysis of NLR levels between these groups.

RESULTS

According to the PRISMA guidelines, fifteen articles were included in the meta-analysis after multiple screenings. The pooled results demonstrated a significant overall elevation of NLR in OA patients compared to healthy controls. (standardized mean difference = 0.39, 95% confidence interval: 0.03-0.75, P = 0.03). However, the subgroup analysis shows no significant differences in NLR levels when considering study design (retrospective vs prospective) and OA severity (severe vs mild-moderate). This suggests variability and potential limitations in using NLR as a consistent marker across different study types and OA severity.

CONCLUSION

Our study found that OA patients have higher NLR than healthy individuals. However, NLR did not significantly differ by study type or disease severity, suggesting its limited use in indicating OA severity.

Is there a relationship between blood inflammation markers and the severity of knee osteoarthritis?

Objectives

This study aims to evaluate the monocyte-to-lymphocyte ratio (MLR), neutrophil-to-lymphocyte ratio (NLR), plateletto-lymphocyte ratio (PLR), and C-reactive protein (CRP)-to-albumin ratio levels between individuals with mild to moderate knee osteoarthritis (OA) and those with severe knee OA.

Patients and methods

One hundred eighty-two participants (131 females, 51 males; mean age: 67.7±10.2 years; range, 43 to 91 years) affected by knee OA were involved in the cross-sectional retrospective study between January 2018 and January 2021. Kellgren and Lawrence (K-L) classification was performed in accordance with two-view (lateral and anteroposterior) plain radiograph examinations of each knee. The patients were grouped as follows: 98 patients had mild to moderate knee OA (K-L Grades 1-2), and 84 had severe knee OA (K-L Grades 3-4). Demographic data, neutrophil, monocyte, platelet, and lymphocyte levels, erythrocyte sedimentation rate, albumin, and CRP levels were documented. C-reactive protein-to-albumin ratio, NLR, MLR, and PLR levels were calculated.

Results

The MLR was significantly elevated in the severe knee OA group (p=0.047). A significant positive relationship was found with disease stage, MLR (r=0.206; p=0.005), and NLR levels (r=0.158; p=0.033). Receiver operating characteristic curve analyses for blood MLR demonstrated a sensitivity of 57% and specificity of 60%.

Conclusion

The study results suggest that while MLR and NLR may reflect the inflammatory response in knee OA, they are not highly diagnostic inflammatory markers that can be used to evaluate the severity or prognosis of the disease.

Eosinophil-to-Lymphocyte Ratio and Eosinophil Count as New Predictive Markers for Osteoarthritis

Purpose

Despite the association between peripheral blood inflammatory biomarkers and a range of inflammatory diseases, the role of these biomarkers in osteoarthritis (OA) progression remains unclear. Additionally, whether alterations in these inflammatory markers impact the prognosis of OA patients remains an understudied area. The aim of our study was to investigate the specific associations between peripheral blood inflammatory markers and OA progression and OA-related mortality.

Methods

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) database from 1999 through 2018. The primary outcomes were all-cause mortality, cardiac mortality, and renal disease mortality, with information on the corresponding mortality rates for each participant obtained through association with the National Death Index (NDI). Multivariate logistic regression models were used to examine the relationship between peripheral blood lymphocyte counts and OA, and restricted cubic spline (RCS) analysis was utilized to assess whether there was a nonlinear relationship with OA and mortality of OA patients. Interaction and stratified analyses were employed to explore the association between peripheral blood leukocyte counts and OA.

Results

This study included 1077 OA patients and 21,612 non-OA participants. In model 3 fully adjusted for covariates, eosinophil-to-lymphocyte ratio (ELR) and eosinophil (EOS) were positive risk factors promoting the development of OA (OR = 3.26, 95% CI: 1.49-7.14; OR = 1.79, 95% CI: 1.12-2.88). In stratified models for age, sex, BMI, smoking status, and alcohol consumption, the associations of ELR and EOS with OA were significantly different. RCS curves showed a J-shaped relationship between ELR and EOS and all-cause mortality in patients with OA. ELR was also found to significantly up-regulate cardiac mortality and renal mortality in patients with OA (OR = 3.92, 95% CI: 1.68-9.14; OR = 22.55, 95% CI: 6.55-77.70), while EOS was only significantly positively correlation (OR = 3.68, 95% CI: 1.94-7.01).

Conclusion

A significant relationship was found between ELR, EOS and OA. In addition, ELR and EOS were identified as potential predictors of mortality from different causes in patients with OA.

Association of peripheral inflammatory indicators with osteoarthritis risk

Objectives

Numerous studies have established the role of inflammation in osteoarthritis (OA) progression, yet limited research explores the association between systemic inflammatory indicators and pre-diagnosis OA risk. This study aimed to investigate the association between peripheral inflammatory indicators and the risk of OA using data from the UK Biobank.

Methods

The study analyzed data from 417,507 participants in the UK Biobank, including neutrophil count, lymphocyte count, monocyte count, platelet count, and C-reactive protein meter. Additionally, derived ratios such as NLR(neutrophils-lymphocytes ratio), PLR(Platelets-lymphocytes ratio), SII(systemic immune-inflammation index), and LMR (lymphocytes-monocytes ratio) were examined. Cox proportional hazards models and restricted cubic spline models were used to assess both linear and nonlinear associations.

Results

Over a mean follow-up period of 12.7 years, a total of 49,509 OA events were identified. The findings revealed that CRP (HR:1.06, 95%CI:1.05-1.07), NLR (HR:1.02, 95%CI:1.01-1.03), PLR (HR:1.02, 95%CI:1.01-1.03), and SII (HR:1.03, 95%CI:1.01-1.04) were associated with an increased risk of OA, while LMR (HR:0.97, 95%CI:0.96-0.99) showed a significant negative correlation with OA risk. Subgroup analyses further emphasized that these associations were significant across most of the population. Although neutrophils, lymphocytes, monocytes, and platelets showed a nominal association with the risk of OA, the results were unreliable, especially for specific joint OA.

Conclusion

The study provides evidence of a significant association between elevated peripheral inflammatory indicators and OA risk. These findings underscore the importance of low-grade chronic inflammation in OA development. The potential clinical utility of these indicators as early predictors of OA is suggested, warranting further exploration.

Inflammatory burden index: associations between osteoarthritis and all-cause mortality among individuals with osteoarthritis

BACKGROUND

The newly described inflammatory burden index (IBI) reflects a patient's inflammatory burden. This study aimed to estimate the association between IBI, osteoarthritis (OA), and all-cause mortality in patients with OA.

METHODS

We extracted the data of adults from the National Health and Nutrition Examination Survey database between 1999 and 2018. After using appropriate survey weights to correct for sample bias, we conducted multivariate logistic regression analyses to explore the association between IBI and OA across three models: in the unadjusted model, partially adjusted model (adjusting age, sex, race, education level, marital status, PIR, BMI, smoking status, drinking status, stroke, CVD, DM, and hypertension) and fully adjusted model (which included additional variables: HBA1C, ALT, AST, BUN, TC, and HDL). And the odds ratios (OR) and 95% confidence intervals (CI) were calculated. Similarly, using comparable survey weights and covariates adjustments, we employed Cox proportional hazards regression analysis to investigate the association between IBI and all-cause mortality in the other 3 models. The Cox proportional hazards regression models were fitted to calculate the hazard ratios (HR) and 95% CI of the association between IBI and all-cause mortality. A restricted cubic spline (RCS) was used to explore the nonlinear relationships between association effects. Subgroup analysis was performed to validate the reliability of their effects.

RESULTS

In total, 22,343 eligible participants were included. Multiple logistic regression models revealed that participants with the highest IBI had 2.54 times (95%CI, 2.23, 2.90)) higher risk of OA than those with the lowest IBI in Model 1, whereas the OR was 1.21 (95%CI, 1.03, 1.42) in Model 2 and 1.23 (95%CI,1.05, 1.45) in Model 3. Multiple Cox regression models showed participants with the highest IBI had 186% (95%CI, 1.50, 2.31) times risk of developing all-cause death than those with the lowest IBI in Model 1. This trend remained stable in Models 2 (HR,1.54; 95%CI,1.22, 1.95) and 3 (HR, 1.41; 95%CI, 1.10, 1.80). The RCS revealed a significant positive association between IBI and OA risk. With respect to the association between IBI and all-cause mortality, a slight decrease in mortality was observed from the lowest quartile to the second quartile of IBI, and the mortality risk increased with increasing IBI. Subgroup analyses showed that age, cardiovascular disease, and hypertension were pivotal in the association of IBI with all-cause mortality, whereas the association of IBI with OA remained stable after stratification by other factors such as sex, race, education level, marital, smoking, and drinking status, hypertension, and most serological indices.

CONCLUSIONS

This study provides evidence of a positive association between IBI, OA, and all-cause mortality. IBI may be a promising signature for assessing the inflammatory burden in patients with OA, which, in turn, is conducive to precise references for high-risk population recognition, anti-inflammatory guidance, and reducing mortality intervention.

Depression heightened the association of the systemic immune-inflammation index with all-cause mortality among osteoarthritis patient

BACKGROUND

Systemic immune-inflammatory index (SII) has been recognized as a novel inflammatory indicator in numerous diseases. It remains unknown how SII affects all-cause mortality among patients with osteoarthritis (OA). In this prospective cohort study, we intended to examine the relationship of SII with all-cause mortality among OA populations and assess the interaction between depression and SII.

METHODS

Data was collected from National Health and Nutrition Examination Survey (NHANES) in 2005-2018. The National Death Index (NDI) provided vital status records. Multivariable Cox regression analyses with cubic spines were applied to estimate the association between SII and all-cause and CVD mortality. Stratified analysis and interaction tests assessed the interaction of SII and depression on all-cause mortality.

RESULTS

In total 3174 OA adults were included. The lowest quartile Q1 (HR:1.44, 95%CI:1.02-2.04) and highest quartile Q4 (HR:1.44, 95%CI:1.02-2.04) of SII presented a higher risk of death compared with those in second quartile Q2 (Ref.) and third quartile Q3 (HR:1.23, 95%CI:0.89-1.68. Restricted cubic splines analysis revealed a U-shaped association of SII with all-cause mortality, the inflection points were 412.93 × 109/L. The interaction test observed a more significant relationship of SII with all-cause mortality in depression patients than in non-depression patients, indicating that depression can modify this association.

LIMITATIONS

First, the observational study design failed to make causal inferences. Second, the baseline SII cannot reflect the long-term level of inflammation. Finally, there may be potential bias.

CONCLUSION

SII was U-shaped associated with all-cause mortality in OA patients, and this association was significantly heightened by depression.

Synovial fluid monocyte-to-lymphocyte ratio in knee osteoarthritis patients predicts patient response to conservative treatment: a retrospective cohort study

BACKGROUND

Biomarkers that predict the treatment response in patients with knee osteoarthritis are scarce. This study aimed to investigate the potential role of synovial fluid cell counts and their ratios as biomarkers of primary knee osteoarthritis.

METHODS

This retrospective study investigated 96 consecutive knee osteoarthritis patients with knee effusion who underwent joint fluid aspiration analysis and received concomitant intra-articular corticosteroid injections and blood tests. The monocyte-to-lymphocyte ratio (MLR) and neutrophil-to-lymphocyte ratio (NLR) were calculated. After 6 months of treatment, patients were divided into two groups: the responder group showing symptom resolution, defined by a visual analog scale (VAS) score of ≤ 3, without additional treatment, and the non-responder group showing residual symptoms, defined by a VAS score of > 3 and requiring further intervention, such as additional medication, repeated injections, or surgical treatment. Unpaired t-tests and univariate and multivariate logistic regression analyses were conducted between the two groups to predict treatment response after conservative treatment. The predictive value was calculated using the area under the receiver operating characteristic curve, and the optimal cutoff value was determined.

RESULTS

Synovial fluid MLR was significantly higher in the non-responder group compared to the responder group (1.86 ± 1.64 vs. 1.11 ± 1.37, respectively; p = 0.02). After accounting for confounding variables, odds ratio of non-responder due to increased MLR were 1.63 (95% confidence interval: 1.11-2.39). The optimal MLR cutoff value for predicting patient response to conservative treatment was 0.941.

CONCLUSIONS

MLR may be a potential biomarker for predicting the response to conservative treatment in patients with primary knee osteoarthritis.

Comparative analysis of late-stage rheumatoid arthritis and osteoarthritis reveals shared histopathological features

OBJECTIVES

Osteoarthritis (OA) is a debilitating and heterogeneous condition, characterized by various levels of articular cartilage degradation, osteophytes formation, and synovial inflammation. Multiple evidences suggest that synovitis may appear early in the disease development and correlates with disease severity and pain, therefore representing a relevant therapeutic target. In a typical synovitis-driven joint disease, namely rheumatoid arthritis (RA), several pathotypes have been described by our group and associated with clinical phenotypes, disease progression, and response to therapy. However, whether these pathotypes can be also observed in the OA synovium is currently unknown.

METHODS

Here, using histological approaches combined with semi-quantitative scoring and quantitative digital image analyses, we comparatively characterize the immune cell infiltration in a large cohort of OA and RA synovial tissue samples collected at the time of total joint replacement.

RESULTS

We demonstrate that OA synovium can be categorized also into three pathotypes and characterized by disease- and stage-specific features. Moreover, we revealed that pathotypes specifically reflect distinct levels of peripheral inflammation.

CONCLUSIONS

In this study, we provide a novel and relevant pathological classification of OA synovial inflammation. Further studies investigating synovial molecular pathology in OA may contribute to the development of disease-modifying therapies.

Individual immune cell and cytokine profiles determine platelet-rich plasma composition

OBJECTIVE

Platelet-rich plasma (PRP) therapy is increasingly popular to treat musculoskeletal diseases, including tendinopathies and osteoarthritis (OA). To date, it remains unclear to which extent PRP compositions are determined by the immune cell and cytokine profile of individuals or by the preparation method. To investigate this, we compared leukocyte and cytokine distributions of different PRP products to donor blood samples and assessed the effect of pro-inflammatory cytokines on chondrocytes.

DESIGN

For each of three PRP preparations (ACP®, Angel™, and nSTRIDE® APS), products were derived using whole blood samples from twelve healthy donors. The cellular composition of PRP products was analyzed by flow cytometry using DURAClone antibody panels (DURAClone IM Phenotyping Basic and DURAClone IM T Cell Subsets). The MESO QuickPlex SQ 120 system was used to assess cytokine profiles (V-PLEX Proinflammatory Panel 1 Human Kit, Meso Scale Discovery). Primary human chondrocyte 2D and 3D in vitro cultures were exposed to recombinant IFN-γ and TNF-α. Proliferation and chondrogenic differentiation were quantitatively assessed.

RESULTS

All three PRP products showed elevated portions of leukocytes compared to baseline levels in donor blood. Furthermore, the pro-inflammatory cytokines IFN-γ and TNF-α were significantly increased in nSTRIDE® APS samples compared to donor blood and other PRP products. The characteristics of all other cytokines and immune cells from the donor blood, including pro-inflammatory T cell subsets, were maintained in all PRP products. Chondrocyte proliferation was impaired by IFN-γ and enhanced by TNF-α treatment. Differentiation and cartilage formation were compromised upon treatment with both cytokines, resulting in altered messenger ribonucleic acid (mRNA) expression of collagen type 1A1 (COL1A1), COL2A1, and aggrecan (ACAN) as well as reduced proteoglycan content.

CONCLUSIONS

Individuals with elevated levels of cells with pro-inflammatory properties maintain these in the final PRP products. The concentration of pro-inflammatory cytokines strongly varies between PRP products. These observations may help to unravel the previously described heterogeneous response to PRP in OA therapy, especially as IFN-γ and TNF-α impacted primary chondrocyte proliferation and their characteristic gene expression profile. Both the individual's immune profile and the concentration method appear to impact the final PRP product.

TRIAL REGISTRATION

This study was prospectively registered in the Deutsches Register Klinischer Studien (DRKS) on 4 November 2021 (registration number DRKS00026175).

Are inflammatory parameters an independent predictor of hip osteoarthritis severity? A prospective cross-sectional study

OBJECTIVE

This study aimed to investigate the relationship between the presence of hip osteoarthritis and the neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, monocyte-lymphocyte ratio, and neutrophil-monocyte ratio.

METHODS

Participants with hip osteoarthritis and healthy controls aged 45-75 years were recruited in the study. The participants with hip osteoarthritis were divided into two groups: mild/moderate hip osteoarthritis and severe hip osteoarthritis. Complete blood parameters of the participants were recorded, and neutrophil-lymphocyte ratio, neutrophil-monocyte ratio, monocyte-lymphocyte ratio, and platelet-lymphocyte ratio were calculated. Pain severity was evaluated using a visual analog scale.

RESULTS

A total of 76 participants with hip osteoarthritis and 59 healthy controls were included in the study. The mean age of the participants was 57.6±6.11 years. Mean neutrophil-lymphocyte ratio and neutrophil-monocyte ratio values were statistically significantly different between the hip osteoarthritis group and healthy control group (p<0.05). Platelet-lymphocyte ratio, monocyte-lymphocyte ratio, erythrocyte sedimentation rate, and C-reactive protein values were not significantly different between the groups. Also, there was no difference between all inflammatory parameters and hip osteoarthritis severity (p>0.05).

CONCLUSIONS

Neutrophil-lymphocyte ratio and neutrophil-monocyte ratio values were higher in patients with hip osteoarthritis than in healthy controls. Mean platelet-lymphocyte ratio, monocyte-lymphocyte ratio, erythrocyte sedimentation rate, and C-reactive protein values did not change according to the presence of hip osteoarthritis. Not all hematological indices give valuable information regarding the severity of hip osteoarthritis.

A Simple Nomogram for Predicting Osteoarthritis Severity in Patients with Knee Osteoarthritis

Objective

To explore the influencing factors of knee osteoarthritis (KOA) severity and establish a KOA nomogram model.

Methods

Inpatient data collected in the Department of Joint Surgery, Chengde Medical University Affiliated Hospital from January 2020 to January 2022 were used as the training cohort. Patients with knee osteoarthritis who were admitted to the Third Hospital of Hebei Medical University from February 2022 to May 2022 were taken as the external validation group of the model. In the training group, the least absolute shrinkage and selection operator (LASSO) method was used to screen the factors of KOA severity to determine the best prediction index. Then, after combining the significant factors from the LASSO and multivariate logistic regressions, a prediction model was established. All potential prediction factors were included in the KOA severity prediction model, and the corresponding nomogram was drawn. The consistency index (C-index), area under the receiver operating characteristic (ROC) curve (AUC), GiViTi calibration band, net classification improvement (NRI) index, and integrated discrimination improvement (IDI) index evaluation of a model predicted KOA severity. Decision curve analysis (DCA) and clinical influence curves were used to study the model's potential clinical value. The validation group also used the above evaluation indexes to measure the diagnostic efficiency of the model. Spearman correlation was used to investigate the relationship between nomogram-related markers and osteoarthritis severity.

Results

The total sample included 572 patients with knee osteoarthritis, including 400 patients in the training cohort and 172 patients in the validation cohort. The nomogram's predictive factors were age, pulse, absolute value of lymphocytes, mean corpuscular haemoglobin concentration (MCHC), and blood urea nitrogen (BUN). The C-index and AUC of the model were 0.802. The GiViTi calibration band (P = 0.065), NRI (0.091), and IDI (0.033) showed that the modified model can distinguish between severe KOA and nonsevere KOA. DCA showed that the KOA severity nomogram has clinical application value with threshold probabilities between 0.01 and 0.78. The external verification results also show the stability and diagnosis of the model. Age, pulse, MCHC, and BUN are correlated with osteoarthritis severity.

Conclusions

A nomogram model for predicting KOA severity was established for the first time that can visually identify patients with severe KOA and is novel for indirectly evaluating KOA severity by nonimaging means.

Neutrophil-to-Lymphocyte Ratio Is Not Associated with Severity of Coronary Artery Disease and Is Not Correlated with Vitamin D Level in Patients with a History of an Acute Coronary Syndrome

Coronary artery disease (CAD), the leading cause of death worldwide, has an underlying cause in atherosclerosis. The activity of this inflammatory process can be measured with neutrophil-to-lymphocyte ratio (NLR). The anti-inflammatory and anti-atherogenic properties of vitamin D affect many mechanisms involved in CAD. In this study, we investigated the association between NLR, vitamin D concentration, and severity of CAD in a group of patients with a history of myocardial infarction (MI). NLR was higher in patients with acute coronary syndrome (ACS) in comparison to those with stable CAD (median: 2.8, range: 0.96−24.3 vs. median: 2.3, range: 0.03−31.6; p < 0.05). No associations between NLR and severity of CAD (p = 0.14) in the cohort and in the subgroups with stable CAD (p = 0.40) and ACS (p = 0.34) were observed. We found no correlation between vitamin D level and NLR neither in the whole study group (p = 0.29) nor in subgroups of patients with stable CAD (p = 0.84) and ACS (p = 0.30). NLR could be used as prognostic biomarker of consecutive MI in patients with CAD and a history of MI.

Elevated Serum Uric Acid Increases the Risk of Ischemic Stroke Recurrence and Its Inflammatory Mechanism in Older Adults

Background

Serum uric acid (UA) has been reported to be associated with ischemic stroke and inflammation. However, whether or not UA is related to the recurrence of ischemic stroke, and whether inflammation plays a role in the relationship between them remain inconclusive.

Objective

We sought to explore the relationship between UA and the recurrence of ischemic stroke and to define the role of neutrophil-to-lymphocyte ratio (NLR) in the aforementioned relationship.

Methods

A total of 8,995 patients were included in this study. Basic information and blood samples were collected, and whether or not each participant experienced ischemic stroke recurrence within 3 years was documented. Patients were stratified into three groups according to their UA level, as follows: ≤ 266, 267–339, and ≥ 340 μmol/L. COX regression and restricted cubic spline regression models were used to evaluate the clinical correlation between UA and ischemic stroke recurrence, mediation analysis and interaction and joint analysis were used to evaluate the role of NLR in the association of UA and ischemic stroke recurrence, and sensitivity and subgroup analyses were performed to test the robustness of the data.

Results

Ischemic stroke recurrence was related to male sex, older age, higher UA level, higher NLR, hypertension, diabetes, and cardiovascular disease. Following adjustment for potential confounders, a high level of UA (≥ 340 μmol/L) increased the risk of recurrence by 92.6% in patients with previous ischemic stroke. We also found that NLR affects the association between UA and the recurrence of ischemic stroke in older adults, suggesting that patients with high NLR and high UA levels are at greater risk for ischemic stroke recurrence.

Conclusion

UA level is non-linearly associated with recurrence, and NLR has an additive interaction between UA and ischemic stroke recurrence.

Welch-weighted Egger regression reduces false positives due to correlated pleiotropy in Mendelian randomization

Modern population-scale biobanks contain simultaneous measurements of many phenotypes, providing unprecedented opportunity to study the relationship between biomarkers and disease. However, inferring causal effects from observational data is notoriously challenging. Mendelian randomization (MR) has recently received increased attention as a class of methods for estimating causal effects using genetic associations. However, standard methods result in pervasive false positives when two traits share a heritable, unobserved common cause. This is the problem of correlated pleiotropy. Here, we introduce a flexible framework for simulating traits with a common genetic confounder that generalizes recently proposed models, as well as a simple approach we call Welch-weighted Egger regression (WWER) for estimating causal effects. We show in comprehensive simulations that our method substantially reduces false positives due to correlated pleiotropy while being fast enough to apply to hundreds of phenotypes. We apply our method first to a subset of the UK Biobank consisting of blood traits and inflammatory disease, and then to a broader set of 411 heritable phenotypes. We detect many effects with strong literature support, as well as numerous behavioral effects that appear to stem from physician advice given to people at high risk for disease. We conclude that WWER is a powerful tool for exploratory data analysis in ever-growing databases of genotypes and phenotypes.

TNF-α Carried by Plasma Extracellular Vesicles Predicts Knee Osteoarthritis Progression

Objectives

To identify plasma extracellular vesicles (EVs) associated with radiographic knee osteoarthritis (OA) progression.

Methods

EVs of small (SEV), medium (MEV) and large (LEV) sizes from plasma of OA participants (n=30) and healthy controls (HCs, n=22) were profiled for surface markers and cytokine cargo by high-resolution flow cytometry. The concentrations of cytokines within (endo-) and outside (exo-) EVs were quantified by multiplex ELISA. EV associations with knee radiographic OA (rOA) progression were assessed by multivariable linear regression (adjusted for baseline clinical variables of age, gender, BMI and OA severity) and receiver operating characteristic (ROC) curve analysis.

Results

Based on integrated mean fluorescence intensity (iMFI), baseline plasma MEVs carrying CD56 (corresponding to natural killer cells) predicted rOA progression with highest area under the ROC curve (AUC) 0.714 among surface markers. Baseline iMFI of TNF-α in LEVs, MEVs and SEVs, and the total endo-EV TNF-α concentration, predicted rOA progression with AUCs 0.688, 0.821, 0.821, 0.665, respectively. In contrast, baseline plasma exo-EV TNF-α (the concentration in the same unit of plasma after EV depletion) did not predict rOA progression (AUC 0.478). Baseline endo-EV IFN-γ and exo-EV IL-6 concentrations were also associated with rOA progression, but had low discriminant capacity (AUCs 0.558 and 0.518, respectively).

Conclusions

Plasma EVs carry pro-inflammatory cargo that predict risk of knee rOA progression. These findings suggest that EV-associated TNF-α may be pathogenic in OA. The sequestration of pathogenic TNF-α within EVs may provide an explanation for the lack of success of systemic TNF-α inhibitors in OA trials to date.

Molecular Classification of Knee Osteoarthritis

Knee osteoarthritis (KOA) is the most common form of joint degeneration with increasing prevalence and incidence in recent decades. KOA is a molecular disorder characterized by the interplay of numerous molecules, a considerable number of which can be detected in body fluids, including synovial fluid, urine, and blood. However, the current diagnosis and treatment of KOA mainly rely on clinical and imaging manifestations, neglecting its molecular pathophysiology. The mismatch between participants' molecular characteristics and drug therapeutic mechanisms might explain the failure of some disease-modifying drugs in clinical trials. Hence, according to the temporal alteration of representative molecules, we propose a novel molecular classification of KOA divided into pre-KOA, early KOA, progressive KOA, and end-stage KOA. Then, progressive KOA is furtherly divided into four subtypes as cartilage degradation-driven, bone remodeling-driven, inflammation-driven, and pain-driven subtype, based on the major pathophysiology in patient clusters. Multiple clinical findings of representatively investigated molecules in recent years will be reviewed and categorized. This molecular classification allows for the prediction of high-risk KOA individuals, the diagnosis of early KOA patients, the assessment of therapeutic efficacy, and in particular, the selection of homogenous patients who may benefit most from the appropriate therapeutic agents.

Extracellular Vesicles as Biological Indicators and Potential Sources of Autologous Therapeutics in Osteoarthritis

Along with cytokines, extracellular vesicles (EVs) released by immune cells in the joint contribute to osteoarthritis (OA) pathogenesis. By high-resolution flow cytometry, we characterized 18 surface markers and 4 proinflammatory cytokines carried by EVs of various sizes in plasma and synovial fluid (SF) from individuals with knee OA, with a primary focus on immune cells that play a major role in OA pathogenesis. By multiplex immunoassay, we also measured concentrations of cytokines within (endo) and outside (exo) EVs. EVs carrying HLA-DR, -DP and -DQ were the most enriched subpopulations in SF relative to plasma (25–50-fold higher depending on size), suggesting a major contribution to the SF EV pool from infiltrating immune cells in OA joints. In contrast, the CD34⁺ medium and small EVs, reflecting hematopoietic stem cells, progenitor cells, and endothelial cells, were the most significantly enriched subpopulations in plasma relative to SF (7.3- and 7.7-fold higher). Ratios of EVs derived from neutrophils and lymphocytes were highly correlated between SF and plasma, indicating that plasma EVs could reflect OA severity and serve as systemic biomarkers of OA joint pathogenesis. Select subsets of plasma EVs might also provide next generation autologous biological products for intra-articular therapy of OA joints.

Novel inflammatory markers in the blood of patients with knee synovitis

OBJECTIVE

Synovitis is a joint disease that seriously affects patient quality of life, but there are currently no diagnostic markers. The albumin to fibrinogen ratio (AFR) and monocyte to lymphocyte ratio (MLR) are non-invasive and cost-effective markers for various systemic inflammatory diseases. However, these markers have not yet been investigated for synovitis. This cross-sectional study evaluated the predictive ability of AFR and MLR in patients with non-specific knee synovitis.

METHODS

One hundred fifty-five patients with knee synovitis and 108 healthy control patients were enrolled. Patient characteristics, blood parameters, AFRs, and MLRs were assessed, and the diagnostic value of these factors was determined.

RESULTS

Among 125 patients included, patients with synovitis had a lower AFR and higher MLR than control subjects. The diagnostic values of AFR and MLR were 0.86 and 0.84, respectively, and higher compared with other parameters by receiver operating characteristic curve assessments. Additionally, MLR was negatively correlated with AFR. Late-stage patients showed significantly lower AFRs and significantly higher MLRs than early-stage patients. Binary logistic regression analyses indicated that AFR was an independent predictor for synovitis severity.

CONCLUSIONS

The AFR and MLR had high diagnostic value for knee synovitis. The AFR was an independent predictor for synovitis severity.

Association between Oncostatin M Expression and Inflammatory Phenotype in Experimental Arthritis Models and Osteoarthritis Patients

Pro-inflammatory cytokines are considered to play a major role in osteoarthritis (OA), yet so far, the specific cytokines involved in the pathology of OA have not been identified. Oncostatin M (OSM) is a cytokine from the interleukin 6 (IL-6) family that has been shown to be elevated in synovial fluid of most rheumatoid arthritis (RA) patients, but only in a limited subset of OA patients. Little is known about OSM in the different joint tissues during OA and how its expression correlates with hallmarks of disease. Here, we mapped OSM expression in the joint tissues of two rat models of arthritis: an acute inflammatory model and an instability-induced osteoarthritic model. OSM expression was correlated with hallmarks of OA, namely cartilage damage, synovitis, and osteophyte formation. Reanalysis of an existing dataset on cytokine profiling of OA synovial fluid was performed to assess pattern differences between patients positive and negative for OSM. In the inflammatory model, OSM expression correlated with synovitis and osteophyte formation but not with cartilage damage. On the contrary, in the instability model of OA, an increase in synovitis, cartilage damage, and osteophyte formation was observed without changes in OSM expression. In line with these findings, synovial fluid of OA patients with detectable OSM contained higher levels of other inflammatory cytokines, namely interferon gamma (IFN-γ), IL-1α and tumor necrosis factor alpha (TNF-α), likely indicating a more inflammatory state. Taken together these data indicate OSM might play a prominent role in inflammatory phenotypes of OA.

Frequency, pattern, and associations of generalized osteoarthritis among Nigerians with knee osteoarthritis

BACKGROUND

Osteoarthritis (OA) is a common degenerative condition leading to significant pain, functional limitation, and economic loss. Generalized OA (GOA) is associated with greater morbidity and accounts for 5-25% of total OA cases depending on definition used. This paper aims to determine the frequency and pattern of GOA, compare clinical and laboratory parameters of GOA and non-GOA subjects, then identify independent associations of GOA among Nigerians with knee OA.

METHODS

A cross-sectional study of 180 knee OA patients with knee and generalized OA defined using ACR criteria. Questionnaire administration was followed by physical examination and appropriate radiographs. Data was summarized using tables and figures. Multivariate regression was done to identify independent GOA associations with statistical significance p<0.05. Ethical approval was obtained for the study.

RESULTS

There were 180 participants with mean age 59.7±9.1 years. Twenty-eight patients (15.6%) had GOA of which 26 were female. The hip/knee/spine pattern was the commonest while hand OA was rare. Comparisons showed that GOA patients were significantly older with longer pain duration, higher pain score, more Heberden's nodes, and greater fatigue. There were no significant differences between both groups in levels of inflammatory markers and other laboratory parameters. Further analysis identified joint stiffness as the only independent association of GOA (OR 3.34, p=0.01).

CONCLUSION

A 15.6% frequency of GOA was identified among knee OA sufferers with the hip/knee/spine pattern most frequent. Nigerians with GOA are predominantly females with a large joint phenotype. Joint stiffness was the only independent association of GOA observed. Key Points • Generalized osteoarthritis occurs in 15.6% of Nigerian patients with knee osteoarthritis. • Females are predominantly affected with a large joint phenotype involving the hip/knee/spine. • Joint stiffness is an independent association of generalized osteoarthritis.

Hematological Inflammatory Markers in Patients with Pemphigus Vulgaris

BACKGROUND

Emerging evidence indicates that several hematological markers can be used to evaluate treatment response, prediction, and early relapse detection in different inflammatory conditions. This study aimed to investigate the correlation between the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, platelet-to-neutrophil ratio, mean platelet volume, and disease activity in patients with pemphigus vulgaris.

METHODS

Fifty-six patients (20 men, 36 women; mean age 54 ± 14 years) diagnosed with pemphigus vulgaris were included in this retrospective study. Patients were divided into those treated and not treated with rituximab (groups 1 and 2), and into those who did and did not develop relapse (groups 3 and 4). The neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, platelet-to-neutrophil ratio and mean platelet volume were evaluated at the time of diagnosis, remission, and relapse. The relationship between each marker and disease stage was analyzed using the Wilcoxon rank-sum test for pairwise comparisons.

RESULTS

The neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio showed a positive correlation with disease activity, while the platelet-to-neutrophil ratio and mean platelet volume showed a negative correlation. The neutrophil-to-lymphocyte ratio significantly decreased in remission (p < 0.001) and significantly increased in relapse (p < 0.01). The platelet-to-lymphocyte ratio significantly decreased in remission (p < 0.001) and showed no significant change in relapse. The platelet-to-neutrophil ratio significantly increased in remission (p < 0.001) and significantly decreased at relapse (p < 0.001). The mean platelet volume significantly increased in remission (p < 0.001) and decreased non-significantly at relapse. A more significant decrease in the neutrophil-to-lymphocyte ratio in remission was found in patients not treated with rituximab. No significant differences were observed between patients who developed relapse and those who did not.

CONCLUSION

Our results suggest that the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, platelet-to-neutrophil ratio, and mean platelet volume can be useful markers for monitoring treatment response, while the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio can also assist in detecting early relapse.

Neutrophil to lymphocyte ratio and fracture severity in young and middle-aged patients with tibial plateau fractures

PURPOSE

The neutrophil-to-lymphocyte ratio (NLR) has recently been found to be closely associated with the severity of trauma. This study aimed to analyze the correlation between the imaging severity of isolated tibial plateau fractures (TPFs) and the NLR in the blood.

METHODS

A total of 223 patients with isolated TPFs were enrolled in this retrospective study over five years. The data at hospital admission were extracted from an electronic database. Schatzker classification was performed according to the imaging data by two experienced orthopaedic surgeons. All patients were divided into two groups: group 1 included patients with mild-to-moderate fractures (Schatzker types I-IV), and group 2 included patients with severe fractures (Schatzker types V-VI). The NLR levels at hospital admission were statistically compared between the two groups.

RESULTS

The blood NLR, hemoglobin level, red blood cell count, neutrophil count, platelet count, time from injury to admission, total protein, and Na+ levels were significantly different among the two groups. According to the receiver operating characteristic (ROC) curve, the cutoff for the NLR was 5.8. ROC curve analysis showed that the sensitivity of an NLR ≥ 5.8 to predict severe TPFs was 53.4%, and the specificity was 70.7%. In the multivariate analysis, NLR ≥ 5.8 and haemoglobin < lower limit appeared to be independent predictors of severe TPFs.

CONCLUSIONS

Our study is the first to demonstrate that the NLR level appears to be a useful biomarker for predicting the severity of isolated TPFs in young and middle-aged adults.

Multiple preoperative biomarkers are associated with incidence of surgical site infection following surgeries of ankle fractures

The aim of the study was to investigate the epidemiologic characteristics of surgical site infection (SSI) following surgeries of ankle fractures. This was a retrospective study. Patients who underwent surgeries for ankle fractures in our hospital between January 2016 and June 2019 were included. Inpatient medical records were inquired for data collection, including demographics, comorbidities, injury-related data, laboratory biomarkers, and confirmation of the SSI cases. Univariate analyses and multivariate logistic regression analyses were used to identify the independent risk factors. Among the 1532 patients, 45 had a postoperative SSI, indicating the incidence rate of 2.9%. About 18% of SSIs were identified after discharge. Twenty percent of SSIs were caused by mixed bacteria, and 39% were caused by drug-resistant bacteria. In the final multivariate model, 7 factors including 5 biomarkers were identified to be independently associated with SSI: gender (male vs female, OR, 2.69; 95% CI, 1.33-4.76), perioperative blood transfusion (OR. 3.02; 95% CI, 1.30-7.04), albumin <35 g/L (OR, 2.87; 95% CI, 1.31-6.31), lower high-density lipoprotein cholesterol (HDL-C) (OR, 2.34; 95% CI, 1.19-4.60), haemoglobin (OR, 2.16; 95% CI, 1.03-4.67), elevated alanine aminotransferase (OR, 2.09; 95% CI, 1.10-3.95) and neutrophile/lymphocyte rate (NLR, OR, 3.45; 95% CI, 1.33-6.74). These epidemiologic data on SSI may help counsel patients about the risk of SSI, individualised assessment of the risk factors, and accordingly the risk stratification.

Inflammatory and Oxidative Stress Markers-Mirror Tools in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic progressive autoimmune disease, associated with significant morbidity, mainly due to progressive damage and consequent disability. Oxidative stress is an important part of RA pathophysiology, as in autoimmune disease the interaction between immune response and endogenous/exogenous antigens subsequently induce the production of reactive oxygen species. The oxidative stress process seems to be positively strongly correlated with inflammation and accelerated joint destruction. We were asking ourselves if the oxidative stress biomarkers are the mirror tools of disease activity, outcome, and inflammation level in a group of RA patients under standard or biological therapy compared to healthy age-matched controls. In order to do this, the oxidative stress damage biomarkers (lipids peroxide and protein carbonyl level), antioxidant defense capacity, and pro-inflammatory status of plasma were quantified. In this study, we took into account the complete picture of RA diseases and assessed, for the first time, the inflammatory level in correlation with the oxidative stress level and antioxidant capacity of RA patients. Our results revealed that protein oxidation through carbonylation is significantly increased in RA groups compared to controls, and both protein carbonyl Pcarb and thiobarbituric acid reactive substance (TBARS) are reliable markers of ROS damage. Therefore, it is unanimous that neutrophil/lymphocyte ratio (NLR), monocyte/lymphocyte ratio ( MLR), platelet/lymphocyte ratio (PltLR) correlated with Pcarb, and TBARS can provide a view of the complex phenomenon represented by proteins/lipids damage, key contributors to disease outcome, and an increased awareness should be attributed to these biomarkers.

Cathepsin g Degrades Both Glycosylated and Unglycosylated Regions of Lubricin, a Synovial Mucin

Lubricin (PRG4) is a mucin type protein that plays an important role in maintaining normal joint function by providing lubrication and chondroprotection. Improper lubricin modification and degradation has been observed in idiopathic osteoarthritis (OA), while the detailed mechanism still remains unknown. We hypothesized that the protease cathepsin G (CG) may participate in degrading lubricin in synovial fluid (SF). The presence of endogenous CG in SF was confirmed in 16 patients with knee OA. Recombinant human lubricin (rhPRG4) and native lubricin purified from the SF of patients were incubated with exogenous CG and lubricin degradation was monitored using western blot, staining by Coomassie or Periodic Acid-Schiff base in gels, and with proteomics. Full length lubricin (∼300 kDa), was efficiently digested with CG generating a 25-kDa protein fragment, originating from the densely glycosylated mucin domain (∼250 kDa). The 25-kDa fragment was present in the SF from OA patients, and the amount was increased after incubation with CG. A CG digest of rhPRG4 revealed 135 peptides and 72 glycopeptides, and confirmed that the protease could cleave in all domains of lubricin, including the mucin domain. Our results suggest that synovial CG may take part in the degradation of lubricin, which could affect the pathological decrease of the lubrication in degenerative joint disease.

The relationship of platelet to lymphocyte ratio and neutrophil to monocyte ratio to radiographic grades of knee osteoarthritis

OBJECTIVE

Accumulating data show that platelet to lymphocyte ratio (PLR) and neutrophil to monocyte ratio (NMR) undergo changes during inflammation in various diseases; however, the clinical features remain unclear in knee osteoarthritis (OA) patients. The purpose of our study was to evaluate PLR and NMR in knee OA patients, and assess their relationship to knee OA's radiographic grades.

METHODS

A retrospective study on 132 adult knee OA patients and 162 healthy controls (HC) was performed. All clinical characteristics of the knee OA patients were obtained from their medical records. PLR and NMR were compared between knee OA patients and HC by non-parametric tests. Correlations of PLR and NMR with Kellgren-Lawrence (KL) classification (KL grade 2, KL grade 3, and KL grade 4) were also analyzed through a Spearman correlation test. Ordinal polytomous logistic regression was used to determine independent factors influencing radiographic grades of knee OA patients.

RESULTS

PLR was increased significantly in knee OA patients, while a statistical difference in NMR was not observed. However, PLR was not relevant to KL grades, while NMR was negatively correlated with these (r = -0.330, P < 0.01) and was independently associated with KL grades of knee OA.

CONCLUSION

PLR could reflect the inflammation response of knee OA. NMR emerged as an independent factor and could be used as a potential marker indicating the severity of knee OA.

Diagnostic value of the blood monocyte-lymphocyte ratio in knee osteoarthritis

Objective

Knee osteoarthritis (KOA) is a chronic inflammatory disease. The monocyte–lymphocyte ratio (MLR) was reported to be a non-invasive, cost-effective marker in various systemic diseases, but it has not yet been investigated in KOA. This cross-sectional study evaluated the diagnostic value of MLR in KOA.

Methods

Two hundred and five KOA patients and 120 healthy control subjects were enrolled. Patient data, including age, sex, blood cell counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) levels, red blood cell distribution width, and the Kellgren–Lawrence (KL) score were recorded.

Results

One hundred nineteen patients (55 men, 64 women) were included, with a mean age of 55.47 ± 9.23 years. KOA patients showed a significantly higher MLR, neutrophil–lymphocyte ratio (NLR), and platelet–lymphocyte ratio (PLR) than controls. The MLR area under the curve was 0.81, which was higher than that of NLR and PLR. Multiple logistic regression analysis revealed blood MLR as an independent predictor of KOA. Correlation analysis showed that MLR was positively correlated with ESR and CRP levels. MLR and NLR were significantly higher in KL4 patients than in KL1–3 patients.

Conclusions

MLR has a high diagnostic value for KOA, so could be a reliable disease marker.

Comparison of blood platelet distribution width and neutrophil-lymphocyte ratio in patients with different grades of knee osteoarthritis

OBJECTIVE

The aim of this study was to compare platelet distribution width (PDW) and neutrophil to lymphocyte ratio (NLR) values in mild-to-moderate and severe knee osteoarthritis (OA).

METHODS

This was a retrospective study of patients with knee OA according to the Kellgren-Lawrence (KL) grading system. Of 465 patients, 231 were excluded (62 due to not meeting the inclusion criteria and 169 due to the lack of simultaneous haemogram and radiographic evaluations). Demographic characteristics and PDW and NLR values were recorded. The patients were then divided into two groups: KL grade 1-3 (mild-to-moderate OA) and KL grade 4 (severe OA).

RESULTS

In severe knee OA patients, blood PDW (13.44 ± 2.58, p= 0.01) and NLR values (2.16 ± 0.84, p= 0.04) were elevated as compared with those in mild-to-moderate knee OA patients. Blood PDW and NLR values of ⩾ 12.5 and ⩾ 2.1, respectively, were taken as cut-offs based on a receiver operating characteristics (ROC) curve analysis. In the ROC curve analysis, blood NLR ⩾ 2.1 had 60% sensitivity and 64.8% specificity, and PDW ⩾ 12.5 had 61% sensitivity and 58% specificity in predicting severe knee OA. In a univariate analysis, age (p< 0.001), PDW ⩾ 12.5 (p= 0.029) and blood NLR ⩾ 2.1 (p= 0.030) emerged as significant predictors of the severe knee OA.

CONCLUSION

The results suggested that the blood PDW and NLR are novel inflammatory markers that can predict the radiographic severity of knee OA in clinical practice.

A novel biomarker in patients with knee osteoarthritis: adropin

Adropin is newly discovered peptide hormone. Osteoarthritis (OA) is a kind of joint disease characterized by progressive joint cartilage loss and joint pain. The present study was carried out to investigate adropin and tumor necrosis factor alpha (TNF-α) levels and the relationship between adropin in patients with knee OA classified by Kellgren-Lawrence (KL). A total of 60 knee OA patients and 30 healthy controls were included in this study. KL grading was carried out using the radiographic findings. Demographic characteristics and laboratory parameters were recorded. Adropin and TNF-α levels were determined by using enzyme-linked immunosorbent assay (ELISA). Adropin level was lower in the knee OA patients compared with the healthy controls (p < 0.001), whereas TNF-α level was higher (p < 0.001). Adropin level was negatively correlated with TNF-α level, blood white blood cell (WBC) count, and neutrophil-lymphocyte ratio (NLR). However, there was a significant decrease in adropin level and an increase in TNF-α level parallel to the increase in the KL grade. In addition, serum adropin level was found to be significantly lower in KL grade 1 groups compared with healthy controls (p < 0.01). There was a decrease in adropin level parallel to the increase in the body mass index (BMI), and there was a statistically significant decrease in adropin level in knee OA patients higher than BMI > 30 (p < 0.01). Mean NLR of KL grade 4 was significantly increased compared with other grades (p < 0.05). The consequence of the present study suggested that serum adropin level could be used as a new biomarker indicating the early grade of knee OA.

Osteoarthritis biomarkers: year in review

OBJECTIVE

To summarise important findings from biomarker studies relevant to osteoarthritis (OA), published between April 2016 and March 2017; to consider these findings in the context of new discoveries and technologies, and clinical and scientific need in OA.

DESIGN

Studies were selected by PubMed search, conducted between 01/04/2016 and 01/03/2017. MeSH terms [biomarker] AND [OA] were used; the search was restricted to Human, English language and Full Text Available publications, which yielded 50 eligible publications. Any biomarker was considered, including non-proteins and other clinical measurements.

RESULTS

Three main areas are overviewed: 1) Studies examining highly validated biomarkers, in the FNIH OA Biomarkers Consortium and elsewhere, particularly their ongoing application and validation. Control reference intervals, work on predictive validity and other longitudinal studies examining prognostic value of biomarkers in large cohorts are reviewed. 2) Novel studies relating to biomarkers of inflammation are discussed, including complement, the performance of markers of so-called 'cold inflammation' and results from clinical trials including biomarkers. 3) Discovery studies, including whole blood RNA, proteomics and metabolomics are reviewed, with an emphasis on new technologies.

CONCLUSIONS

Discovery, characterisation and qualification of various biomarkers is ongoing; several novel protein and non-protein candidate biomarkers have been reported this year. Biomarkers provide us with an opportunity to better diagnose and stratify the disease, via established panels or new discovery approaches. Improving quality of sampling and testing, and measuring large numbers of markers simultaneously in large cohorts would seem likely to identify new clinically applicable biomarkers, which are still much needed in this disease.

Comparisons of neutrophil-, monocyte-, eosinophil-, and basophil- lymphocyte ratios among various systemic autoimmune rheumatic diseases

This study was aimed to evaluate levels of neutrophil- (NLR), monocyte- (MLR), eosinophil- (ELR), and basophil-lymphocyte ratio (BLR) and their association with inflammatory markers in systemic autoimmune rheumatic diseases (SARDs). A total of 1139 SARD patients and 170 healthy individuals were enrolled. Clinical and laboratory data were extracted. NLR and MLR were significantly increased, but BLR decreased in most SARD patients (p < 0.05). ELR were significantly decreased in systemic lupus erythematosus (SLE) patients, but increased in those with other SARDs (p < 0.001). In SLE patients, C-reactive protein (CRP) showed positive correlation with NLR, MLR, and BLR. IgG negatively correlated with NLR, and did positively with ELR. IgM negatively correlated with NLR and MLR. In those with rheumatoid arthritis (RA), ankylosing spondylitis (AS), and osteoarthritis (OA), NLR and MLR positively correlated with erythrocyte sedimentation rate (ESR) and CRP. In primary Sjögren's syndrome (pSS) patients, ESR showed positive correlation with NLR and MLR. IgA had positive correlation with BLR. In polymyositis/dermatomyositis (PM/DM) patients, ESR and CRP positively correlated with NLR. Additionally, significant correlations were also found between CRP and BLR, IgG and ELR, IgM and ELR. In systemic sclerosis (SSc) patients, clear correlations were only observed between CRP and NLR or MLR. In mixed connective tissue disease (MCTD) patients, NLR positively correlated with ESR and CRP, while NLR and MLR did negatively with IgM. In polymyalgia rheumatic (PMR) patients, MLR positively correlated with CRP, while ELR did negatively with IgG. This study demonstrated increased NLR and MLR and deceased BLR in most SARDs, decreased ELR in SLE and increased ELR in other SARDs. Furthermore, NLR and MLR may be useful tools to reflect inflammatory status of SARDs.

Evaluation of blood neutrophil-lymphocyte ratio and platelet distribution width as inflammatory markers in patients with fibromyalgia

Fibromyalgia syndrome (FMS) is characterized by chronic widespread pain and systemic symptoms. The aetiology and pathogenesis of fibromyalgia are not yet fully understood. Blood neutrophil/lymphocyte ratio (NLR) is a marker of systemic inflammatory response. Platelet distribution width (PDW) and mean platelet volume (MPV) are the determinants of platelet activation and studied as markers in inflammatory diseases. The aim of the present study was to evaluate levels of NLR,PDW and MPV in patients with fibromyalgia. A total of 197 FMS patients and 53 healthy controls are included in the study. Demographic characteristics, erythrocyte sedimentation rate, C-reactive protein, neutrophil, lymphocyte and platelet counts, platelet distribution width and mean platelet volume levels were recorded. In the patient group, the blood NLR and MPV were significantly higher and the PDW was significantly lower compared to the control group. In the roc curve analysis, blood PDW ≥had 90.4% sensitivity and 90% specificity in predicting fibromyalgia. The results of this study suggest NLR and PDW as promising inflammatory markers indicating fibromyalgia and may be beneficial in facilitating the diagnosis of FMS patients.

Associations between body composition and nutritional assessments and biochemical markers in patients with chronic radiation enteritis: a case-control study

Background

Chronic radiation enteritis (CRE) is defined as loss of absorptive capacity after irradiation due to chronic inflammation and damage of intestinal mucosa, which may lead to varying degrees of malnutrition. The aim of this study was to evaluate the potential correlation between the nutritional status and systemic inflammation in patients with CRE.

Methods

Medical records of 92 patients with CRE and 184 age- and sex-matched controls in a single center from January 2010 to October 2015 were retrospectively reviewed. All enrolled subjects underwent nutritional status analysis, including three different nutritional indices: Nutritional Risk Screening-2002 (NRS-2002), Patient-generated Subjective Global Assessment (PG-SGA) and Controlling Nutritional Status (CONUT), bioelectrical impedance spectroscopy (BIS), and biochemical markers, within 24 h of admission.

Results

The results showed that NRS-2002, PG-SGA and CONUT were all positively correlated with neutrophil/lymphocyte ratio (NLR) (r = 0.304, 0.384 and 0.425, all p < 0.001) and C-reactive protein (CRP) (r = 0.357, 0.479 and 0.230, all p < 0.001), while negatively correlated with albumin (r = −0.612, −0.727 and −0.792, all p < 0.001) and total cholesterol (TC) (r = −0.485, −0.545 and −0.473, all p < 0.001) in patients with CRE, respectively. Body cell mass (BCM) has been deemed a key body composition parameter. It was positively correlated with albumin (r = 0.489, p < 0.001) and TC (r = 0.237, p < 0.001), while negatively correlated with NLR (r = −0.140, p = 0.02) and CRP (r = −0.215, p < 0.001). A multivariate linear regression analysis showed that values of intracellular water (β coefficient = 0.760, p < 0.001), extracellular water (β coefficient = 0.006, p = 0.011), protein (β coefficient = 0.235, p < 0.001) and CRP (β coefficient = 0.001, p = 0.009) were independent determinants of BCM.

Conclusion

This study revealed that BIS combined with nutritional assessments and biochemical markers were appropriate methods to assess the nutritional and inflammatory status in patients with CRE. Furthermore, the nutritional status was verified to be significantly correlated with systemic inflammation.