Background: Patients with rheumatoid arthritis (RA) have an increased risk of cardiovascular (CV) events and CV mortality. Subclinical carotid atherosclerosis is independently associated with rates of incident CV events among patients with RA. The complement system has been related to both the etiopathogenesis of RA and CV disease. In this study, we aimed to evaluate the association between a comprehensive assessment of the complement system and carotid intima media thickness and carotid plaque in patients with RA. Methods: 430 patients with RA were recruited. Functional assays of the three pathways of the complement system, utilizing new-generation techniques, were assessed. Additionally, serum levels of individual components of the complement system belonging to the three pathways were measured: C1q (classical), lectin (lectin), C2, C4, and C4b (classical and lectin), factor D and properdin (alternative), C3 and C3a (common), C5, C5a, and C9 (terminal), as well as regulators factor I and C1-inhibitor. Subclinical carotid atherosclerosis was evaluated by ultrasonography. Multivariable linear regression analysis was conducted to investigate the association between the complement system and carotid intima media thickness and carotid plaque. Results: After multivariable adjustment, which included traditional CV risk factors and disease-related data, C3a and C5a exhibited significant positive correlations with carotid intima media thickness. Additionally, higher values of C1-inhibitor, properdin, C3, C5, and C5a were independently associated with the presence of carotid plaque. Conclusion: The complement system and subclinical carotid atherosclerosis are linked in patients with RA.

Transforming growth factor beta (TGF-β) is a highly pleiotropic cytokine that has broad anti-inflammatory and immunosuppressive effects. In patients with systemic lupus erythematosus (SLE), the immunosuppressive effect of TGF-β1 is thought to be dysfunctional. In the present work, we aimed to study the relationship between the serum levels of TGF-β1 with the characteristics of the disease as well as with the patterns of activity, damage, or severity of the disease. Two hundred and eighty-four patients with well-characterized SLE were recruited. The serum levels of TGF-β1 were assessed. A multivariable linear regression analysis was performed to analyze the relation of disease characteristics to TGF-β1. The Katz severity index (beta coefficient 179 [95% confidence interval 7–350] pg/mL, p = 0.041) and SLEDAI activity index (beta coefficient 96 [95% CI 20–171] pg/mL, p = 0.014) were associated with higher serum levels of TGF-β1 after the multivariable analysis. When the disease-specific features were studied, ocular and cardiovascular manifestations were positively associated with serum TGF-β1 levels. In contrast, gastrointestinal and musculoskeletal involvements were associated with lower levels of circulating TGF-β1. Among patients with SLE, the serum levels of TGF-β1 were highly associated with disease-related manifestations.

Background/Objectives: Patients with periodontitis have been found to have higher salivary concentrations of malondialdehyde, a biomarker of lipid hyperoxidation, compared to healthy subjects. However, the association between salivary malondialdehyde levels and periodontitis, independently of other risk factors, has not been analyzed. Therefore, the novel objective of our study was to explore this possible association by performing a logistic regression analysis. Material and Methods: This observational, prospective study was carried out in a private dental practice. Salivary malondialdehyde levels were measured in subjects with periodontitis (characterized by periodontal tissue loss) and in subjects without periodontitis (either periodontally healthy or with localized gingivitis in <30% of sites). A multivariate regression analysis was carried out to determine the factors associated with periodontitis. Variables with a p-value ≤ 0.05 in the comparison between subjects with and without periodontitis were included in the regression analysis. Results: A total of 119 subjects were included, 63 with periodontitis and 56 without (35 periodontally healthy subjects and 21 patients with localized gingivitis). In the multiple binomial regression analysis, salivary malondialdehyde levels > 0.77 nmol/mL were identified as a predictor of periodontitis (p = 0.03), after controlling for age (p < 0.001), diabetes mellitus (p = 0.81), arterial hypertension (p = 0.43), smoking status (never smoked p = 0.08), and cardiovascular disease (p = 0.88). Conclusions: To our knowledge, this is the first study to report that salivary malondialdehyde levels are associated with periodontitis, independently of other known risk factors.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder identified by hematological abnormalities including anemia, leukopenia, and thrombocytopenia. Complement system disturbance is implicated in the pathogenesis of SLE. In this work, we aim to study how a full assessment of the complement system, which includes the evaluation of its three pathways, relates to blood cell counts in a population of patients with SLE. New-generation functional assays of the classical, alternative, and lectin pathways of the complement system were conducted in 284 patients with SLE. Additionally, serum levels of inactive molecules (C1q, C2, C3, C4, factor D) and activated molecules (C3a), as well as regulators (C1-inhibitor and factor H), were evaluated. Complete blood cell counts were analyzed. Multivariable linear regression analysis was performed to study the relationship of hematological profiles with this full characterization of the complement system. After multivariable adjustments that included age, sex, SLICC-DI (damage), and SLEDAI (activity) scores, as well as the use of aspirin, prednisone, methotrexate, azathioprine, and mycophenolate mofetil, several relationships were observed between the C pathways and the individual products and blood cells profile. Lower values of C1q and C2 were associated with lower hemoglobin levels. Lower leukocyte counts showed significantly lower values of C4, C1 inhibitor, C3, factor D, and alternative pathway functional levels. Neutrophil counts showed significant negative relationships only with the alternative pathway and C1-inh. In the case of lymphocytes, associations were found, especially with functional tests of the classical and alternative pathways, as well as with C2, C4, C3, and C3a. On the contrary, for platelets, significance was only observed, after multivariable adjustment, with lower C2 concentrations. In conclusion, the serum complement system and hematological profile in SLE are independently linked, after adjustment for disease activity and damage. These relationships are basically negative and are predominantly found in lymphocytes.

Background: Transforming growth factor beta (TGF-β1) is a multifunctional cytokine that has anti-inflammatory and immunosuppressive effects. TGF-β1 has been linked to cardiovascular disease in the general population. The immunosuppressive effect of TGF-β1 is believed to be dysregulated in patients with systemic lupus erythematosus (SLE). In the present work, we aimed to study the relationship of serum levels of TGF-β1 with subclinical carotid atherosclerosis in patients with SLE. Methods: The study included 284 patients with SLE. Serum levels of TGF-β1 and subclinical carotid atherosclerosis (by carotid ultrasonography) were evaluated. In addition, the complete lipid profile and insulin resistance were analyzed. Multivariable linear and logistic regression analysis was performed to establish the relationship of TGF-β1 with carotid subclinical atherosclerosis adjusting for traditional cardiovascular risk factors that included lipid profile and insulin resistance. Results: Circulating TGF-β1 was positively and significantly associated with higher levels of LDL:HDL cholesterol ratio and atherogenic index. TGF-β1 was also associated with significantly lower levels of HDL cholesterol and apolipoprotein A1. Remarkably, TGF-β1 was associated with the presence of carotid plaque not only after adjustment for demographics (age, sex, body mass index, diabetes, hypertension, and aspirin use) but also after adjustment for relationships of TGF-β1 with lipid profile molecules, insulin resistance, and SLEDAI disease score (odds ratio 1.14 [95% confidence interval 1.003–1.30], p = 0.045). Conclusion: TGF-β1 serum levels are positively and independently associated with the presence of subclinical atherosclerosis disease in patients with SLE.

The complement (C) system is implicated in the etiopathogenesis of rheumatoid arthritis (RA). However, there is a lack of studies characterizing all three C pathways in RA patients. This study aimed to evaluate the association between an in-depth examination of the C system and RA patient characteristics, focusing on disease activity and the presence of rheumatoid factor and anti-citrullinated protein autoantibodies (ACPA). In a cohort of 430 RA patients, functional assays of the three C pathways (classical, alternative, and lectin) and serum levels of their components were assessed. Components included C1q (classical); factor D and properdin (alternative); lectin (lectin); C1-inhibitor; C2, C4, and C4b (classical and lectin); C3, C3a, and C4b (common); and C5, C5a, and C9 (terminal). A multivariable linear regression analysis showed significant positive correlations between C-reactive protein and C system proteins and functional assays, especially in the terminal and common pathways. Disease activity, measured by scores with or without acute phase reactants, positively correlated with the classical pathway functional test and terminal pathway products. Conversely, rheumatoid factor or ACPA presence was associated with lower classical pathway values and decreased C3a and C4b levels, suggesting complement depletion. In conclusion, RA disease activity increases C molecules and functional complement assays, while rheumatoid factor or ACPA positivity is linked to C consumption. Our study offers a detailed analysis of the complement system’s role in RA, potentially guiding the development of more targeted and effective treatment strategies.