Prospective Study Of Rheumatoid Arthritis Patients Research Articles

Association between skeletal muscle mitochondrial dysfunction and insulin resistance in patients with rheumatoid arthritis: a case–control study

BackgroundInsulin resistance affects a substantial proportion of patients with rheumatoid arthritis (RA). Skeletal muscle mitochondrial dysfunction results in the accumulation of lipid intermediates that interfere with insulin signaling. We therefore sought to determine if lower oxidative phosphorylation and muscle mitochondrial content are associated with insulin resistance in patients with RA.MethodsThis was a cross-sectional prospective study of RA patients. Matsuda index from the glucose tolerance test was used to estimate insulin sensitivity. Mitochondrial content was measured by citrate synthase (CS) activity in snap-frozen muscle samples. Mitochondrial function was measured by using high-resolution respirometry of permeabilized muscle fibers and electron transport chain complex IV enzyme kinetics in isolated mitochondrial subpopulations.ResultsRA participants demonstrated lower insulin sensitivity as measured by the Matsuda index compared to controls [median 3.95 IQR (2.33, 5.64) vs. 7.17 (5.83, 7.75), p = 0.02]. There was lower muscle mitochondrial content among RA vs. controls [median 60 mU/mg IQR (45, 80) vs. 79 mU/mg (65, 97), p = 0.03]. Notably, OxPhos normalized to mitochondrial content was higher among RA vs. controls [mean difference (95% CI) = 0.14 (0.02, 0.26), p = 0.03], indicating a possible compensatory mechanism for lower mitochondrial content or lipid overload. Among RA participants, the activity of muscle CS activity was not correlated with the Matsuda index (ρ = − 0.05, p = 0.84), but it was positively correlated with self-reported (IPAQ) total MET-minutes/week (ρ = 0.44, p = 0.03) and Actigraph-measured time on physical activity (MET rate) (ρ = 0.47, p = 0.03).ConclusionsMitochondrial content and function were not associated with insulin sensitivity among participants with RA. However, our study demonstrates a significant association between muscle mitochondrial content and physical activity level, highlighting the potential for future exercise interventions that enhance mitochondrial efficiency in RA patients.

Clinical impact of musculoskeletal ultrasound on rheumatoid arthritis in routine care.

To evaluate the impact of musculoskeletal ultrasound (MSUS) in the management of rheumatoid arthritis (RA) patients and to investigate factors affecting treatment strategy by the referring rheumatologist. Prospective study of RA patients evaluated at a MSUS clinic over a 6-month period. Data extraction included demographics, current treatment and MSUS findings. Pre- and post-MSUS follow-up of 3months data were analyzed. Patients were classified into 2 groups based on the decision of the referring rheumatologist to change the treatment after the MSUS examination. Comparisons between groups were performed in a univariate analysis. We used logistic regression models to investigate factors associated with changes in clinical management. A total of 64 RA patients were included. Mean age was 61.9years and 83.6% were female. Main referral indication was assessment of disease activity (89%). Overall, MSUS led to subsequent therapeutic actions by the referring rheumatologist in 41 (64.1%) patients, and to a change in the clinical impression of the complaint that generated the referral in 7 (11.5%) patients. The detection of power Doppler (PD), the 28 swollen joint count and the presence of radiographic erosions were significantly associated with a subsequent clinical action. In the multivariate analysis only PD remained significant (odds ratio=3.29; 95% CI: 1.05-10.26). Disease activity evaluation is the most common indication for MSUS examination, with the presence of PD the factor most frequently associated with changes in therapeutic management. This study highlights the impact of MSUS, especially the use of PD, to support treatment decisions in RA routine care.

Incidence, risk factors and validation of the RABBIT score for serious infections in a cohort of 1557 patients with rheumatoid arthritis.

Predicting serious infections (SI) in patients with rheumatoid arthritis (RA) is crucial for the implementation of appropriate preventive measures. Here we aimed to identify risk factors for SI and to validate the RA Observation of Biologic Therapy (RABBIT) risk score in real-life settings. A multi-centre, prospective, RA cohort study in Greece. Demographics, disease characteristics, treatments and comorbidities were documented at first evaluation and one year later. The incidence of SI was recorded and compared with the expected SI rate using the RABBIT risk score. A total of 1557 RA patients were included. During follow-up, 38 SI were recorded [incidence rate ratio (IRR): 2.3/100 patient-years]. Patients who developed SI had longer disease duration, higher HAQ at first evaluation and were more likely to have a history of previous SI, chronic lung disease, cardiovascular disease and chronic kidney disease. By multivariate analysis, longer disease duration (IRR: 1.05; 95% CI: 1.005, 1.1), history of previous SI (IRR: 4.15; 95% CI: 1.7, 10.1), diabetes (IRR: 2.55; 95% CI: 1.06, 6.14), chronic lung disease (IRR: 3.14; 95% CI: 1.35, 7.27) and daily prednisolone dose ≥10 mg (IRR: 4.77; 95% CI: 1.47, 15.5) were independent risk factors for SI. Using the RABBIT risk score in 1359 patients, the expected SI incidence rate was 1.71/100 patient-years, not different from the observed (1.91/100 patient-years; P = 0.97). In this large real-life, prospective study of RA patients, the incidence of SI was 2.3/100 patient-years. Longer disease duration, history of previous SI, comorbidities and high glucocorticoid dose were independently associated with SI. The RABBIT score accurately predicted SI in our cohort.

Calprotectin (S100A8/A9) and S100A12 are associated with measures of disease activity in a longitudinal study of patients with rheumatoid arthritis treated with infliximab

Objectives: The pro-inflammatory proteins calprotectin (a heterocomplex of S100A8/A9) and S100A12 have been associated with disease activity in rheumatoid arthritis (RA). The aim of this study was to compare their potential as biomarkers in a prospective study of RA patients starting with infliximab as their first biological disease-modifying anti-rheumatic drug (DMARD).Method: Thirty-nine RA patients were examined and serum samples collected when starting with infliximab and after 3, 6, and 12 months. Calprotectin and S100A12 were analysed by enzyme-linked immunosorbent assays (ELISAs) and, together with C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), measured at all time points. A disease activity score of 28 joints (DAS28) was calculated. Radiographs of the hands, wrists, and feet were taken at baseline and after 3 years, and assessed according to the modified Sharp/van der Heijde (SvH) score. Responsiveness was evaluated according to the European League of Associations for Rheumatology (EULAR) response criteria based on 28 joints.Results: Both S100 proteins were significantly higher in seropositive than in seronegative patients (p = 0.01). Calprotectin correlated significantly with CRP (ρ = 0.51–0.75), ESR (ρ = 0.32–0.52), and DAS28 (ρ = 0.32–0.62). S100A12 correlated with calprotectin (ρ = 0.62–0.77) and CRP (ρ = 0.32–0.63). The S100 proteins, and especially calprotectin (ρ = 0.23–0.39), showed weak associations with radiographic progression, unlike CRP/ESR. None of the S100 proteins could predict responsiveness.Conclusions: Calprotectin showed the strongest correlation with measures of disease activity and may be better than S100A12 when evaluating disease activity in RA patients. More extensive studies are needed to further compare the predictive value of the S100 proteins relative to radiographic progression.

RENACER study: Assessment of 12-month efficacy and safety of 168 certolizumab PEGol rheumatoid arthritis-treated patients from a Spanish multicenter national database

Objective: To assess effectiveness and safety of certolizumab PEGol (CZP) in rheumatoid arthritis (RA) patients after 12 months of treatment and to detect predictors of response.Methods: Observational longitudinal prospective study of RA patients from 35 sites in Spain. Variables (baseline, 3- and 12-month assessment): sociodemographics, previous Disease Modifying Anti-Rheumatic Drug (DMARD) and previous Biological Therapies (BT) use; TJC, SJC, ESR, CRP, DAS28, SDAI. Response variables: TJC, SJC, CRP, ESR, and steroids dose reductions, EULAR Moderate/Good Response, SDAI response and remission, DAS28 remission. Safety variables: discontinuation due to side-effects. Descriptive, comparative and Logistic regression analyses were performed.Results: We included 168 patients: 79.2% women, mean age 54.5 years (±13.2 SD), mean disease duration 7.5 years (±7.3 SD). Mean number of prior DMARD: 1.4 (±1.2 SD), mean number of prior BT was 0.8 (±1.1). Mean time on CZP was 9.8 months (±3.4 SD). A total of 71.4% were receiving CZP at 12-month assessment. Baseline predictors of response: lower prior number DMARD; low number prior BT; higher CRP, ESR, TJC, SJC, DAS28 and SDAI (p < 0.05) scores. A 25/46.4% Moderate/Good Response, a 20% SDAI remission, and a 44% DAS28 remission were observed. We observed 48 discontinuations (28.6%), 31 due to partial or complete ineffectiveness, and 17 due to side-effects.Conclusions: CZP showed benefit in severe RA patients, with significant reduction of all effectiveness parameters, despite the high prevalence of previous BT exposure in our series. We found CRP, ESR, prior DMARD/BT number, TJC, SJC, DAS28, and SDAI as baseline predictors of response. CZP was mostly well tolerated.