Background. Myostatin is a regulator of muscle size. To date, there have been no published studies focusing on the relation between myostin levels and myopenia in rheumatoid arthritis (RA). Objective. Evaluate the value of serum myostatin as a biomarker of cachexia and low skeletal muscle mass (LSMM) in RA patients, along with whether high serum myostatin is associated to these conditions after adjusting for potential confounders. Methods. This cross-sectional study included 161 female RA patients and 72 female controls. In the RA group, we assessed several potential risk factors for LSMM and rheumatoid cachexia. Dual-energy X-ray absorptiometry was used to quantify the skeletal muscle mass index (SMMI) (considering kg/m²) and the presence of rheumatoid cachexia (a fat-free mass percentile and fat mass percentile of the reference population). Serum myostatin concentrations were determined by ELISA. To identify a cut-off for high serum myostatin levels, we performed ROC curve analysis. Multivariable logistic regression analysis was used to identify the risk factors for LSMM and rheumatoid cachexia. The risk was expressed as odds ratios (ORs) and their 95% confidence intervals (95% CIs). Results. Compared to the controls, the RA group had a higher proportion of LSMM and exhibited high serum myostatin levels ( ). ROC curve analysis showed that a myostatin ng/mL was the most efficient cut-off for identifying rheumatoid cachexia (sensitivity: 53%, specificity: 71%) and LSMM (sensitivity: 43%, specificity: 77%). In the multivariable logistic regression, RA with high myostatin levels (≥17 ng/mL) was found to increase the risk of cachexia ( , 95% CI: 1.24-6.29; ) and LSMM ( , 95% CI: 1.17-7.89; ). Conclusions. High serum myostatin levels increase the risk of LSMM and rheumatoid cachexia. We propose that high myostatin levels are useful biomarkers for the identification of patients in risk of rheumatoid cachexia and myopenia.

The objective of this study was to investigate the usefulness of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) in predicting short-term therapeutic response to methotrexate (MTX) in rheumatoid arthritis (RA). Patients with active RA, with Disease Activity Score-28 joints (DAS-28) >3.2, starting oral MTX, were included. We measured at baseline, 3 and 6 mo: DAS-28, Health Assessment Questionnaire–Disability Index (HAQ-DI), patient’s perception of disease severity, morning stiffness and pain, as well as modifications in sTREM-1 levels. A reduction in DAS-28 > 1.2 at 3 or 6 mo was considered adequate response. A significant decrease in DAS-28 was observed at 3 and 6 mo. HAQ-DI also decreased at 3 and 6 mo. No significant changes were observed in sTREM-1 levels at 3 or 6 mo. Using as cut-off a baseline value of sTREM-1 levels > 390 pg/ml, we obtained low values of sensitivity (61.5%), specificity (59.3%), positive predictive value (59.3%) and negative predictive value (61.5%) for adequate response to MTX at 3 mo. We found no clinical value of sTREM-1 levels in predicting therapeutic response to MTX in RA. Further studies should evaluate if sTREM-1 levels are predictive for other outcomes, including higher structural damage or good response to biologics.

Background: Rheumatoid arthritis (RA) in elderly population represents a challenge for physicians in terms of therapeutic management. Methotrexate (MTX) is the first-line treatment among conventional synthetic-disease-modifying anti-rheumatic drugs (cs-DMARDs); however, it is often associated with adverse events (AEs). Therefore, the objective of this study was to identify the incidence and risk factors of MTX discontinuation due to AEs in elderly patients with RA in a long-term retrospective cohort study. Methods: Clinical sheets from elderly RA patients taking MTX from an outpatient rheumatology consult in a university centre were reviewed. To assess MTX persistence, we used Kaplan–Meir curves and Cox regression models to identify the risk of withdrawing MTX due to adverse events. Results: In total, 198 elderly RA patients who reported using MTX were included. Of them, the rates of definitive suspension of MTX due to AEs were 23.0% at 5 years, 35.6% at 10 years and 51.7% at 15 years. The main organs and system involved were gastrointestinal (15.7%) and mucocutaneous (3.0%). Factors associated with withdrawing MTX due to AEs were MTX dose ≥ 15 mg/wk (adjusted HR: 2.46, 95% CI: 1.22–4.96, p = 0.012); instead, the folic acid supplementation was protective for withdrawal (adjusted HR: 0.28, 95% CI: 0.16–0.49, p < 0.001). Conclusions: Higher doses of MTX increase the risk of withdrawals in elderly RA, while folic acid supplementation reduces the risk. Therefore, physicians working in therapeutic management for elderly patients using MTX must focus on using lower MTX doses together with the concomitant prescription of folic acid.

Rheumatoid arthritis (RA) is a chronic inflammatory disease that affects synovial joints and that frequently involves extra-articular organs. A multiplicity of interleukins (IL) participates in the pathogenesis of RA, including IL-6, IL-1β, transforming growth factor-beta (TGF-β), and tumor necrosis factor (TNF)-α; immune cells such as monocytes, T and B lymphocytes, and macrophages; and auto-antibodies, mainly rheumatoid factor and anti-citrullinated protein antibodies (ACPAs). Skeletal muscle is also involved in RA, with many patients developing muscle wasting and sarcopenia. Several mechanisms are involved in the myopenia observed in RA, and one of them includes the effects of some interleukins and myokines on myocytes. Myostatin is a myokine member of the TGF-β superfamily; the overproduction of myostatin acts as a negative regulator of growth and differentiates the muscle fibers, limiting their number and size. Recent studies have identified abnormalities in the serum myostatin levels of RA patients, and these have been found to be associated with muscle wasting and other manifestations of severe RA. This review analyzes recent information regarding the relationship between myostatin levels and clinical manifestations of RA and the relevance of myostatin as a therapeutic target for future research.

Background: The Perri Auditory Verbal Learning Test (Perri-AVLT) is a cognitive tool that is used to assess verbal learning and memory. To date, demographically adjusted norms for Perri-AVLT have not been identified for Mexican adults. Objectives: This study aimed to 1) estimate the means, standard deviations, and ranges for Perri-AVLT raw scores, 2) develop regression-based norms from healthy participants to enable demographic adjustments for clinical interpretation, and 3) assess test-retest reliability. Methods: The sample included 430 participants (380 cognitively normal individuals and 50 clinical cases) aged 18–59 years from Mexico (Jalisco, Guanajuato and Mexico City). The participants completed the Perri-AVLT. A multivariate regression-based norming approach was used to evaluate the effects of age, sex, and years of education on test performance. Results: Healthy participants aged ≤ 39 years performed significantly better than those aged ≥ 40 years did in all the Perri-AVLT trials. Age and years of education were significant predictors of performance, with older age associated with lower scores and more years of education associated with greater word recall on the Perri-AVLT. Conclusion: We provided normative data for the Perri-AVLT after performing regression analyses adjusted for sociodemographic factors. These norms can be used to evaluate verbal learning and memory in early-to-midlife Mexican adults. This information can support neuropsychologists in the context of cognitive assessment, rehabilitation and research.

Background: The relationship between serum glycoprotein syndecan-1 and disease activity in rheumatoid arthritis (RA) is still unknown. This study aimed to evaluate whether serum syndecan-1 concentrations are associated with moderate/severe disease activity. Methods: Study Design: This was a cross-sectional study. Seventy-five adult women with RA were classified into (a) moderate/severe RA based on the disease activity score, using the erythrocyte sedimentation rate (DAS28-ESR ≥ 3.2, n = 50), and (b) RA in remission (DAS28-ESR < 2.6, n = 25). Twenty-five healthy women were taken as the reference group. Syndecan-1 levels were determined using enzyme-linked immunosorbent assay (ELISA). High values of serum syndecan-1 levels (≥24 ng/mL) were used to identify the utility values of this biomarker. Results: The patients with RA had higher levels of syndecan-1 than the controls (p < 0.001). RA patients with active disease had higher syndecan-1 levels than RA patients in remission (57.6 vs. 23.5 ng/mL, respectively; p = 0.002). High syndecan-1 concentrations demonstrated the following utility values for identifying disease activity: sensitivity, 84% (95%CI: 71–93); specificity, 52% (95%CI: 31–72); positive predictive value, 78% (95%CI: 70–84); and negative predictive value, 62% (95%CI: 44–77). Conclusions: High syndecan-1 levels have good sensitivity and positive predictive value for identifying disease activity; however, their specificity is limited. Future prospective studies are needed to assess whether syndecan-1 levels can predict treatment failure in RA.