Association of synovial fluid and urinary C2C-HUSA levels with surgical outcomes post-total knee arthroplasty.

OBJECTIVES: After total knee arthroplasty (TKA), ∼30% of knee osteoarthritis (KOA) patients show little symptomatic improvement. Earlier studies have correlated urinary (u) type 2 collagen C terminal cleavage peptide assay (C2C-HUSA), which detects a fragment of cartilage collagen breakdown, with KOA progression. This study determines whether C2C levels in urine, synovial fluid, or their ratio, are associated with post-surgical outcomes. METHODS: From a large sample of 489 subjects, diagnosed with primary KOA undergoing TKA, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores were collected at baseline (time of surgery) and one-year post-TKA. Baseline urine (u) and synovial fluid (sf) were analysed using the IBEX-C2C-HUSA assay, with higher values indicating higher amounts of cartilage degradation. For urine, results were normalised to creatinine. Furthermore, subjects' changes in WOMAC scores were categorised based on percent reduction in pain or improvement in function, compared to baseline, such that >66.7%, >33.3 to ≤66.7%, and ≤33.3% denoted "strong", "moderate" and "mild/worse" responses, respectively. Associations of individual biofluid C2C-HUSA levels, or their ratio, with change in WOMAC pain and function scores up to one-year post-TKA, or category of change, were analysed by linear, logistic, or cumulative odds models. RESULTS: Higher baseline uC2C-HUSA levels or a lower ratio of baseline sfC2C-HUSA to uC2C-HUSA were associated with improvements in WOMAC pain by linear multivariable modelling [odds ratio -0.40 (95% confidence interval -0.76, -0.05) p = 0.03; 0.36 (0.01, 0.71), p = 0.04, respectively], while sfC2C-HUSA alone was not. However, lower ratios of sfC2C-HUSA to uC2C-HUSA were associated with improvements in WOMAC function [1.37 (0.18, 2.55), p = 0.02], while sfC2C-HUSA and uC2C-HUSA alone were not. Lower ratios of sfC2C-HUSA to uC2C-HUSA were also associated with an increased likelihood of a subject being categorised in a group where TKA was beneficial in both univariable [pain, 0.81 (0.68, 0.96), p = 0.02; function, 0.92 (0.85, 0.99), p = 0.035] and multivariable [pain, 0.81 (0.68, 0.97) p = 0.02; function, 0.92 (0.85, 1.00), p = 0.043] ordinal modelling, while sfC2C-HUSA and uC2C-HUSA alone were not. CONCLUSIONS: Overall, ratios of baseline sfC2C-HUSA to uC2C-HUSA, and baseline uC2C-HUSA, may play an important role in studying post-TKA surgical outcomes.

Emerging molecular biomarkers in osteoarthritis pathology.

Osteoarthritis (OA) is the most common form of arthritis resulting in joint discomfort and disability, culminating in decline in life quality. Attention has been drawn in recent years to disease-associated molecular biomarkers found in readily accessible biofluids due to low invasiveness of acquisition and their potential to detect early pathological molecular changes not observed with traditional imaging methodology. These biochemical markers of OA have been found in synovial fluid, blood, and urine. They include emerging molecular classes, such as metabolites and noncoding RNAs, as well as classical biomarkers, like inflammatory mediators and by-products of degradative processes involving articular cartilage. Although blood-based biomarkers tend to be most studied, the use of synovial fluid, a more isolated biofluid in the synovial joint, and urine as an excreted fluid containing OA biomarkers can offer valuable information on local and overall disease activity, respectively. Furthermore, larger clinical studies are required to determine relationships between biomarkers in different biofluids, and their impacts on patient measures of OA. This narrative review provides a concise overview of recent studies of OA using these four classes of biomarkers as potential biomarker for measuring disease incidence, staging, prognosis, and therapeutic intervention efficacy.

Evaluation of Tele-rheumatology during the COVID-19 Pandemic in Asian Population: A Pilot Study.

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic autoimmune condition associated with a potential for deformities. It is one of the common conditions to seek health care. Hence, the present study was conducted to assess the telemedicine services for patients suffering from rheumatoid arthritis during the COVID-19 pandemic in an Asian Indian population. METHODS: A prospective study was conducted (March 2020-June 2020) in the telemedicine department of a premier northern Indian tertiary care institution. Out of the total patients enrolled (N = 7577) in telemedicine services, 122 rheumatoid arthritis patients (1.6%) were followed for 1 month to assess change in functional status by modified Health Assessment Questionnaire (mHAQ). Telephonic interviews of the enrolled patients were conducted to determine the level of understanding of advice given by consultants, barriers during the consultation, and satisfaction with teleconsultations for rheumatology clinics. RESULTS: For the native people, language of the clinicians was the main barrier (20%) in telerheumatology. Saving of time and money was observed as beneficial factors for patients. More than three-quarters of all rheumatoid arthritis patients were ready to use teleconsultation in the near future. A similar proportion of patients were in support for the recommendation of these services to other persons. CONCLUSION: We report the successful use of telemedicine services in the evaluation and management of rheumatic diseases in the current COVID-19 pandemic situation.

Clinico-genetic model to predict methotrexate intolerance in rheumatoid arthritis.

INTRODUCTION: Methotrexate is the gold-standard DMARD in rheumatoid arthritis but is often associated with "mild" adverse effects like intolerance or laboratory abnormalities. Although non-life threatening, they are responsible for drug discontinuation in 17-50%. There is limited data on clinical and genetic markers that predict their occurrence. METHODS: This prospective study enrolled patients with active rheumatoid arthritis. They were started on methotrexate at a weekly dose of 15 mg, escalated gradually to reach 25 mg which was continued till the end of the study. Intolerance (symptomatic adverse effects) was ascertained by a questionnaire at 4, 8, 16, and 24 weeks. Laboratory testing for occurrence of cytopenia and/or transaminitis was done at the same study visits. Seven SNPs in four genes involved in methotrexate handling were genotyped using real-time polymerase chain reaction. RESULTS: This study included 110 patients with rheumatoid arthritis who received methotrexate for 24 weeks; the final mean weekly methotrexate dose was 22.0 ± 4.0 mg. Methotrexate intolerance occurred in 40 (37%), common being nausea (and vomiting) in 29 and anxiety (and dizziness) in 9. It was associated with lower BMI at baseline (21.5 ± 3.7, 23.8 ± 4.6 kg/m2, p = 0.01). FPGS rs10106 was significantly associated with intolerance with an allelic odds ratio (95% CI) of 2.02 (1.14-3.57) and the recessive genetic model (AA+AG versus GG) with an odds ratio of 3.8 (95% CI 1.5-9.6, p = 0.004). A model including both BMI and FPGS rs10106 could modestly predict methotrexate intolerance with an accuracy of 66.3%. CONCLUSIONS: A clinical-genetic model including BMI and SNP FPGS 10101 was found to have a modest prediction ability for methotrexate intolerance.Key Points• Methotrexate intolerance (symptomatic adverse effects) was common and occurred in 37% patients over 6 months.• SNP FPGS rs10106 and low body mass index were associated with methotrexate intolerance.• Clinico-genetic model had a modest ability of 66% for predicting intolerance.

Methotrexate preferentially affects Tc1 and Tc17 subset of CD8 T lymphocytes.

Rheumatoid arthritis is considered a T-lymphocyte-mediated disease. However, studies have focussed on CD4 T-lymphocytes, ignoring CD8 T-lymphocytes despite the latter being found abundantly in the synovium. Specifically, there is little data of the effect of methotrexate, the gold-standard DMARD, on various CD8 cytokine T-lymphocyte subsets and conflicting data on CD4 subsets. In this prospective study, patients with active rheumatoid arthritis, who were 18 to 65 years of age, were treated with methotrexate (up to 25 mg per week) for 24 weeks. At baseline and 24 weeks, frequencies of CD8+IFNγ+, CD8+IL17+, CD8+IL4+, corresponding CD4 subsets and plasma levels of IFNγ, IL-12, IL-10, IL-4 and IL-17 were determined by flow cytometry. These are summarised as median (IQR = interquartile range, 25th-75th percentile) and paired data compared using Wilcoxon signed rank test. This study included 67 patients (F/M = 4:1) with rheumatoid arthritis, 57 (85%) being RF positive and 20 receiving prednisolone at baseline. Mean (± SD) dose of methotrexate at 24 weeks was 22.9 ± 3.0 mg per week. On treatment with methotrexate, there was a significant (p = 0.04) decline in CD8+IFNγ+ cells from 37.2 (IQR 19.4-60.2) to 22.7% (IQR 8.5-49.7) and a marginal increase in CD8+IL17+ cells from 0.3 (IQR 0.1-0.6) to 0.4 (IQR 0.2-1.2), p = 0.006. There was no significant change in the other subsets. There was also a significant decline in circulating levels of IL-12, IL-10 and IL-17 and marginal increase in IL-4. On evaluating by response, non-responders but not responders had a significant increase in CD8+IL17+ (p = 0.01). There is a significant decline of CD8+IFNγ+ T cells and marginal increase in CD8+IL17+ T cells after methotrexate. Change in Tc1 subset may be mediated through reduction in IL-12 levels.

Do SNPs in folate pharmacokinetic pathway alter levels of intracellular methotrexate polyglutamates and affect response? A prospective study in Indian patients.

This study investigated the impact of seven polymorphisms in genes of folate transport and (de)glutamation pathway on methotrexate polyglutamate levels and response in patients with rheumatoid arthritis. This prospective study included patients with rheumatoid arthritis. They were treated with methotrexate (up to 25 mg per week) for 24 weeks and categorized by EULAR response criteria into responders (good and moderate) and non-responders. Using real-time Taqman discrimination assay, SNPs were genotyped-rs1045642 (ABCB1 3435C>T), rs1128503 (ABCB1 1236C>T), rs10106 (FPGS 1994A>G), rs1544105 (FPGS G>A), rs11545078 (GGH 452C>T), rs3758149 (GGH -401C>T), and rs1051266 (RFC1 80G>A). RBC methotrexate polyglutamate1-5(MTX-glu1-5) levels were determined at 4, 8, 16, and 24 weeks using by reverse phase HPLC using C-18 column followed by post column photo-oxidation. This study included 117 patients with rheumatoid arthritis (M:F = 14:103). The mean dose of methotrexate at 24 weeks was 22.0 ± 4.0 mg, with data on DAS28(3) at 24 weeks available in 96 patients-61 responders and 35 non-responders. Minor allele of GGH 452C>T had an association with non-response (odds ratio 2.9, 95% CI 1.4-5.6) and assuming the dominance of C, the recessive genetic model found GGH 452C>T CC genotype (odds ratio 9.5, 95% CI 1.2 to 76.0) was significantly associated with response. However, there was no difference in MTX-glu1-5 levels among the various genotypes of this SNP (p = 0.9). Other SNPs were neither associated with response nor with alteration in methotrexate polyglutamate levels. On logistic regression, GGH 452C>T CC genotype and DAS28(3) at baseline were independent predictors of response. GGH 452C>T CC genotype was associated with response to methotrexate. None of the SNPs affected MTX-glu1-5levels.

High Methotrexate Triglutamate Level Is an Independent Predictor of Adverse Effects in Asian Indian Rheumatoid Arthritis Patients-A Preliminary Study.

BACKGROUND: It is unclear whether erythrocyte methotrexate polyglutamate levels (MTX-glun) are associated with response or adverse effects to methotrexate in rheumatoid arthritis. This preliminary study evaluated their utility in Asian Indian patients over 24 weeks. METHODS: Rheumatoid arthritis patients were started on oral methotrexate at a dose of 15 mg/wk, which was escalated to 25 mg by 12 weeks and continued till 24 weeks. Erythrocyte (RBC) MTX-glu1 to MTX-glu5 levels (nmol/L RBC) were determined at 4, 8, 16, and 24 weeks by using reverse-phase high-performance liquid chromatography. Area under the concentration curve (AUC) of MTX-glu1-5, MTX-glu3-5, and MTX-glu3 levels was compared between groups with regards to response and adverse effects. RESULTS: This study included 117 patients with mean (SD) age of 42.7 (±11.9) years and disease duration of 2.0 (1.7) years. Mean (SD) RBC MTX-glu1-5 levels at 4, 8, 16, and 24 weeks were 93 (±29), 129 (±46), 143 (±49), and 159 (±65) nmol/L RBC; the highest individual polyglutamate was MTX-glu3 (40%). There was significant correlation between MTX-glu1-5 (r = 0.38, P < 0.001) and MTX-glu3 (r = 0.49, P < 0.001) with methotrexate dose. There was no significant difference of AUC MTX-glun between responders and nonresponders. However, AUC MTX-glu3 was significantly (P = 0.03) higher in patients with adverse effects. On logistic regression, AUC of MTX-glu3 [odds ratio = 1.004 (95% confidence interval 1.002-1.007)] and methotrexate dose at 24 weeks were independent predictors of adverse effects. CONCLUSIONS: In this preliminary study, higher levels of RBC MTX-glu3 were found to be the independent predictors for adverse effects in rheumatoid arthritis patients.

Comparison of two different folic acid doses with methotrexate--a randomized controlled trial (FOLVARI Study).

INTRODUCTION: There is reasonable evidence that folic acid 5-10 mg per week leads to reduction in methotrexate (MTX) toxicity in rheumatoid arthritis (RA). However, this is based on studies conducted with lower MTX dosage than used currently. It is unclear whether higher doses of folic acid may be better in reducing toxicity. METHODS: This was a double-blind randomized controlled trial of 24 weeks duration. To be eligible, patients should have rheumatoid arthritis (1987 American College of Rheumatology criteria), be 18-75 years of age, not be on MTX and have active disease as defined by 'Modified Disease Activity Score using three variables' (DAS28(3)) > 3.2. MTX was started at 10 mg/week and escalated to 25 mg/week by 12 weeks. Folic acid was given at a dose of 10 mg (FA10) or 30 mg per week (FA30). Co-primary endpoints were incidence of toxicity (undesirable symptoms and laboratory abnormalities) and change in disease activity by 24 weeks. Intention-to-treat and per-protocol analyses were performed. RESULTS: Among 100 patients enrolled, 51 and 49 were randomized to FA10 and FA30 respectively. By 24 weeks, there were 6 patient withdrawals in either group and mean(±SD) dose of MTX was 22.8 ± 4.4 and 21.4 ± 4.6 mg per week (p = 0.1). Frequency of patients with undesirable symptoms was non-significantly lower by 7.4% (95% confidence interval -27.4 to 12.7%) in FA10 compared to FA30. There was also no difference in frequency of transaminitis (>Upper limit of normal (ULN)) (42.6, 45.7%, p = 0.7) or transminitis as per primary endpoint (>2xULN) (10.6, 8.7%, p = 1.0) or cytopenias (4.3, 4.3%, p = 0.9). There was no difference in the primary end-point of occurrence of any adverse effect (symptom or laboratory) in FA10 and FA30 (46.8, 54.3%, p = 0.5). At 24 weeks, DAS28(3) declined in both groups by a similar extent (-1.1 ± 1.0, -1.3 ± 1.0, p = 0.2) and 'European League Against Rheumatism' good or moderate response occurred in 56.9 and 67.4% (p = 0.3). CONCLUSIONS: Even with the high doses of MTX used in current practice, there was no additional benefit (or harm) of a higher dose of folic acid (30 mg/week) over a usual dose (10 mg/week). TRIAL REGISTRATION: Clinicaltrials.gov NCT01583959 Registered 15 March 2012.

Low serum levels of myeloid progenitor inhibitory factor-1 predict good response to methotrexate in rheumatoid arthritis.

Background. Although the benchmark in the treatment of rheumatoid arthritis remains methotrexate, only 70% of patients respond. Thus, there is a need for predictive biomarkers. This study planned to evaluate serum levels of myeloid progenitor inhibitory factor-1 (MPIF-1) and monocyte chemoattractant protein 2 (MCP-2)-as biomarkers. Methods. Patients with rheumatoid arthritis (RA) having high disease activity (DAS28-3v ≥ 5.1) were treated with oral methotrexate (MTX) for 12 weeks. Disease activity was measured by DAS28-3v (Modified Disease Activity Score 3 variables). Serum samples were stored at baseline and 12 weeks. Results. This study included 46 patients (F : M = 35 : 11) having mean (±SD) age of 42.6 ± 11.3 yrs, disease duration of 4.7 ± 4.5 yrs, and DAS28-3v of 6.1 ± 0.8. Serum MPIF1 was elevated in patients compared to controls (1636.7 ± 1009.7, 441.2 ± 173.8 pg/mL, P < 0.001), but there was no difference in MCP2 levels (31.4 ± 11.9, 33.8 ± 24.0 pg/mL). Baseline MPIF-1 level was lower in good responders (ΔDAS28-3v ≥ 1.2, N = 9) compared to poor responders (ΔDAS28-3v < 0.6, N = 27) (1171.0 ± 670.8, 1816.7 ± 1154.1 pg/mL, P = 0.05). On ROC analysis, baseline MPIF1 performed reasonably to predict good response; that is, ΔDAS28-3v ≥ 1.2 (AUC 0.68, 95% CI 0.50-0.87). Conclusions. Lower baseline MPIF1 level predicted a good response to methotrexate at 12 weeks.