Anti-cyclic citrullinated peptide antibodies and paraoxonase-1 polymorphism in rheumatoid arthritis

Association between Paraoxonase/Arylesterase Activity of Serum PON-1 Enzyme and Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

Background: A decrease in serum paraoxonase (PON-1) and arylesterase (ARE) activity has been reported in rheumatoid arthritis (RA) patients and linked to chronic inflammation and impaired antioxidant defense. Methods: A systematic review and meta-analysis were performed to critically appraise the current evidence on plasma/serum concentrations of PON-1 and ARE activity in RA patients and healthy controls. The Web of Science, PubMed, Scopus, and Google Scholar databases were searched from inception to November 2021. We used random-effects meta-analysis. The risk of bias was estimated using the Joanna Briggs Institute Critical Appraisal Checklist tool. The certainty of the evidence was assessed with GRADE. The study complied with the PRISMA statements and was registered in PROSPERO (CRD42022345380). Results: Seventeen studies reported PON-1 activity (1144 RA patients, 797 controls) and ten reported ARE activity (1367 RA patients, 1037 controls). RA patients had significantly lower PON-1 (SMD = −1.32, 95% CI −1.94 to −0.70; p < 0.001) and ARE activity (SMD = −0.91, 95% CI −1.37 to −0.46; p < 0.001). There was substantial heterogeneity (PON, I2 97%; ARE, 95.7%, p < 0.001 for both). There was no publication bias. The pooled SMD values did not significantly change after sensitivity analysis. The certainty of the evidence was very low due to the observational nature of the studies and the large heterogeneity. Conclusion: Our meta-analysis has shown that both serum PON-1 and ARE activity are significantly lower in RA patients, suggesting a deficit in antioxidant defense mechanisms in this disease.

Effects of One-Year Tofacitinib Therapy on Lipids and Adipokines in Association with Vascular Pathophysiology in Rheumatoid Arthritis

Background: Cardiovascular (CV) morbidity, mortality and metabolic syndrome are associated with rheumatoid arthritis (RA). A recent trial has suggested increased risk of major CV events (MACE) upon the Janus kinase (JAK) inhibitor tofacitinib compared with anti-tumor necrosis factor α (TNF-α) therapy. In our study, we evaluated lipids and other metabolic markers in relation to vascular function and clinical markers in RA patients undergoing one-year tofacitinib therapy. Patients and methods: Thirty RA patients treated with either 5 mg or 10 mg bid tofacitinib were included in a 12-month follow-up study. Various lipids, paraoxonase (PON1), myeloperoxidase (MPO), thrombospondin-1 (TSP-1) and adipokine levels, such as adiponectin, leptin, resistin, adipsin and chemerin were determined. In order to assess flow-mediated vasodilation (FMD), common carotid intima-media thickness (IMT) and arterial pulse-wave velocity (PWV) ultrasonography were performed. Assessments were carried out at baseline, and 6 and 12 months after initiating treatment. Results: One-year tofacitinib therapy significantly increased TC, HDL, LDL, APOA, APOB, leptin, adipsin and TSP-1, while significantly decreasing Lp(a), chemerin, PON1 and MPO levels. TG, lipid indices (TC/HDL and LDL/HDL), adiponectin and resistin showed no significant changes. Numerous associations were found between lipids, adipokines, clinical markers and IMT, FMD and PWV (p < 0.05). Regression analysis suggested, among others, association of BMI with CRP and PWV (p < 0.05). Adipokines variably correlated with age, BMI, CRP, CCP, FMD, IMT and PWV, while MPO, PON1 and TSP-1 variably correlated with age, disease duration, BMI, RF and PWV (p < 0.05). Conclusions: JAK inhibition by tofacitinib exerts balanced effects on lipids and other metabolic markers in RA. Various correlations may exist between metabolic, clinical parameters and vascular pathophysiology during tofacitinib treatment. Complex assessment of lipids, metabolic factors together with clinical parameters and vascular pathophysiology may be utilized in clinical practice to determine and monitor the CV status of patients in relation with clinical response to JAK inhibition.

Changes of Metabolic Biomarker Levels upon One-Year Anti-TNF-α Therapy in Rheumatoid Arthritis and Ankylosing Spondylitis: Associations with Vascular Pathophysiology

Background: Cardiovascular (CV) morbidity, mortality, and metabolic syndrome are associated with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Here, lipids and other metabolic markers in relation to vascular function and clinical markers were evaluated in RA and AS patients undergoing one-year anti-TNF therapy. Patients and methods: Fifty-three patients including 36 RA patients treated with either etanercept (ETN) or certolizumab pegol (CZP) and 17 AS patients treated with ETN were included in a 12-month follow-up study. Various lipids, paraoxonase (PON) and arylesterase (ARE) activities, myeloperoxidase (MPO) and adipokine levels were determined overtime. Ultrasonography was performed to determine flow-mediated vasodilation (FMD), common carotid intima-media thickness (ccIMT), and arterial pulse-wave velocity (PWV) in all patients. All assessments were performed at baseline and 6 and 12 months after treatment initiation. Results: Anti-TNF therapy decreased ARE activity, MPO, adiponectin, and chemerin levels after 12 months (p < 0.05). Lipids, PON activity, and leptin remained unchanged. Regression analyses suggested variable associations of IMT, PWV, and FMD with ARE, MPO, leptin, and lipids (p < 0.05). On the other hand, these metabolic parameters were significantly associated with disease duration, CV history, CRP, obesity, PWV, and IMT (p < 0.05). One-year anti-TNF treatment together with baseline leptin (p = 0.039) or CRP (p = 0.016) levels determined 12 months of lipid changes overtime. TNF inhibition together with baseline disease activity determined ARE activity changes (p = 0.046). Anti-TNF therapy and baseline chemerin levels determined IMT changes overtime (p = 0.003). Conclusions: Assessment of various metabolic parameters together with disease activity, CRP, and ultrasound-based techniques may exert additional value in determining CV burden and in monitoring the effects of biologics on preclinical vascular pathophysiology.

Immunological tests and their interpretation in uveitis

Uveitis is a complex disorder including both infectious and non-infectious etiologies. Clinical diagnosis is a challenge because many diseases share common clinical signs. Laboratory support is crucial for confirming the clinical diagnosis. Laboratory diagnosis includes direct tests and indirect tests. For example smear, culture, and molecular diagnostics demonstrate the pathogens, hence they are direct tests. Immunologic tests employ an antigen to detect presence of antibodies to a pathogen, or an antibody to detect the presence of an antigen, of the pathogen in the specimens. The immunological tests used in laboratories are made by producing artificial antibodies that exactly “match” the pathogen in question. When these antibodies come into contact with a sample they bind to the matching pathogen if found in the sample. Hence they are grouped under indirect evidence. There are several investigations in uveitis to reach the confirmed diagnosis including microbiological, immunological, imaging and molecular diagnostic testing. In this section we will discuss immunological investigations of infectious and non-infectious uveitis.

Biomarkers of lipid metabolism in patients with juvenile idiopathic arthritis: relationship with disease subtype and inflammatory activity

BACKGROUND

To describe the biomarkers of lipid metabolism in children and adolescents with polyarticular and systemic JIA and to relate them to diseases subtypes, diseases activity markers, and nutritional status.

METHODS

A cross-sectional study including 62 JIA patients was performed. The following variables were evaluated: disease activity and medications used, body mass index, height for age (z-score), skin folds (bicipital, tricipital, subscapular and suprailiac), food intake based on three 24-h food recalls, lipid profile (total cholesterol (CT), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and non-HDL (N-HDLc), glycemia and insulin, erythrocyte sedimentation rate (ESR), ultrasensitive C-reactive protein (us-CRP) and apolipoproteins A-I and B (Apo A-I and Apo B).

RESULTS

Dyslipidemia was observed in 83.3% of the patients. Based on classical lipid profile, low HDL-c levels was the most frequently alteration observed. Inadequate levels of LDL-c, Apo B and NHDL-c were significantly more frequent in the systemic JIA subtype when compared to the polyarticular subtype (p = 0.017, 0.001 and 0.042 respectively). Patients on biological therapy had a better adequacy of Apo A-I concentrations. The ESR showed a negative correlation with Apo A-I level (r = - 0.25, p = 0.047).

CONCLUSION

We concluded that dyslipidemia is common in patients with JIA, especially in systemic subtype. The systemic subtype and an elevated ESR were associated with lower concentrations of Apo A-I, suggesting the participation of the inflammatory process.

Oxidative Stress Biomarkers and Peripheral Endothelial Dysfunction in Rheumatoid Arthritis: A Monocentric Cross-Sectional Case-Control Study

Previous studies have suggested that oxidative stress may heighten atherosclerotic burden in rheumatoid arthritis (RA), but direct evidence is lacking.

OBJECTIVE

To evaluate the relationship between established plasma oxidative stress biomarkers and peripheral endothelial dysfunction (ED), a marker of early atherosclerosis, in RA.

METHODS

Paroxonase-1 (PON-1), protein-SH (PSH), and malondialdehyde (MDA) were measured in 164 RA patient s and 100 age- and sex-matched healthy controls without previous cardiovascular events. Peripheral ED, evaluated by flow-mediated pulse amplitude tonometry, was defined by log-transformed reactive hyperemia index (Ln-RHI) values < 0.51.

RESULTS

PON-1 activity and PSH concentrations were significantly reduced in RA patients compared to controls. In regression analysis, increased plasma MDA levels were significantly associated with reduced Ln-RHI [B coefficient (95% CI) = -0.003 (-0.005 to -0.0008), p = 0.008] and the presence of peripheral ED (OR (95% CI) = 1.75 (1.06-2.88), p = 0.028). Contrary to our expectations, increased PON-1 activity was significantly associated, albeit weakly, with the presence of ED (OR (95% CI) = 1.00 (1.00-1.01), p = 0.017).

CONCLUSIONS

In this first evidence of a link between oxidative stress and markers of atherosclerosis, MDA and PON-1 showed opposite associations with peripheral vasodilatory capacity and the presence of ED in RA. Further studies are needed to determine whether this association predicts atherosclerotic events in the RA population.

PON-1 haplotype (-108C>T, L55M, and Q192R) modulates the serum levels and activity PONase promoting an atherogenic lipid profile in rheumatoid arthritis patients

INTRODUCTION/OBJECTIVE

Paraoxonase 1 (PON1) promotes antioxidant and antiatherogenic activity related to the hydrolysis of oxidized lipids of low-density lipoproteins. In rheumatoid arthritis (RA) patients, it has been reported that low PON1 activity is related to an impaired lipid profile, increasing cardiovascular risk (CVR). The goal of this study was to analyze the effect of common PON1 polymorphisms and haplotypes on enzymatic activity, PON1 serum levels (PON1s), and lipid parameters related to atherogenic profile in RA patients.

METHODS

A cross-sectional study was carried out on 250 Mexican patients with RA. The lipid profile was determined by colorimetric tests. The PON1 activity (CMPAase) was measured by spectrophotometry. The levels of PON1s were determined by ELISA, and the polymorphisms in the PON-1 gene (-108C>T, L55M, and Q192R) were genotyped by the PCR-RFLP method. The haplotypes were estimated and statistical analysis was performed.

RESULTS

The median of the CMPAase activity and PON1 levels was 13.91 U/mL and 24.75 ng/mL, respectively. The CMPAase activity was significantly lower in carriers of -108TT and 192QQ genotypes (β = - 4.09, P = 0.001 and β = - 3.73, P = 0.002, respectively); moreover, the PON1 levels were lower in 192Q allele carriers (P < 0.01). The TLQ haplotype was associated with CMPAase activity < 13.91 U/mL (OR = 2.29, P < 0.001), as well as with levels of PON1s < 24.75 ng/mL (OR = 1.65, P = 0.017). In this study, the CMPAase activity (< 13.91 U/mL) showed a positive association with lower levels of high-density lipoprotein cholesterol (HDL-c; < 40/50 mg/dL), and with a triglycerides/HDL-c ratio > 3%, and a total cholesterol/HDL-c ratio > 4.5/5%, all representatives of an atherogenic risk lipid profile.

CONCLUSIONS

PON1 polymorphisms modulate the CMPAase activity and PON1 levels in Mexican patients with RA. The CMPAase activity < 13.91 U/mL is associated with an atherogenic lipid profile, independently of inflammation markers and treatment with anti-rheumatic drugs. Key Points •The haplotype TLQ is a marker for low PONase activity in rheumatoid arthritis. •The haplotype TLQ is a marker for low PON1 serum levels in rheumatoid arthritis. •The enzymatic PON1 activity represents the best marker for an atherogenic lipid profile in rheumatoid arthritis, in comparison with PON1 levels. •The haplotype TLQ is a marker of low PON1 activity, levels of PON1s, and atherogenic lipid profile, independent of treatment therapy in rheumatoid arthritis.

Rheumatoid factor versus anti - cyclic citrullinated peptide antibody as screening tool for rheumatoid arthritis in an ophthalmic clinic

Patients with moderate to severe dry eyes are often screened at the Dry Eye Clinic to rule out connective tissue diseases. Rheumatoid factor (RF) is one of the screening tools to rule out rheumatoid arthritis (RA). Patients who turn out positive for the RF are often subjected to anti-CCP antibody evaluation for confirmation of disease. This article tries to highlight 3 cases of negative and anti-CCP antibody positive cases which presented to the ophthalmic clinic, unaware of their systemic status. Though RF is the cheapest modality to screen for RA, it is not always a reliable marker. One should order anti-CCP antibody for patients where suspicion is high, despite RF being normal.

Autoantibodies as Diagnostic Markers and Mediator of Joint Inflammation in Arthritis

Rheumatoid arthritis is a systemic, polygenic, and multifactorial syndrome characterized by erosive polyarthritis, damage to joint architecture, and presence of autoantibodies against several self-structures in the serum and synovial fluid. These autoantibodies (anticitrullinated protein/peptide antibodies (ACPAs), rheumatoid factors (RF), anticollagen type II antibodies, antiglucose-6 phosphate isomerase antibodies, anticarbamylated protein antibodies, and antiacetylated protein antibodies) have different characteristics, diagnostic/prognostic value, and pathological significance in RA patients. Some of these antibodies are present in the patients' serum several years before the onset of clinical disease. Various genetic and environmental factors are associated with autoantibody production against different autoantigenic targets. Both the activating and inhibitory FcγRs and the activation of different complement cascades contribute to the downstream effector functions in the antibody-mediated disease pathology. Interplay between several molecules (cytokines, chemokines, proteases, and inflammatory mediators) culminates in causing damage to the articular cartilage and bones. In addition, autoantibodies are proven to be useful disease markers for RA, and different diagnostic tools are being developed for early diagnosis of the clinical disease. Recently, a direct link was proposed between the presence of autoantibodies and bone erosion as well as in the induction of pain. In this review, the diagnostic value of autoantibodies, their synthesis and function as a mediator of joint inflammation, and the significance of IgG-Fc glycosylation are discussed.

Gadolinium-based contrast agents: in vitro paraoxonase 1 inhibition, in silico studies

Medications show their biological effects by interaction with enzymes, which have been known to play an essential role in the pathogenesis of many diseases. Inhibition or induction of drug metabolizing enzymes has an essential place in the drug design for many kinds of diseases including cardiovascular, neurological, metabolic, and cancer. The main goal of the current study is to contribute to this growing drug design field by observing PON1-drug interactions. In recent years, the safety of gadolinium-based contrast agents (GBCAs) used in magnetic resonance imaging (MRI) has discussed. In the present study, paraoxonase 1 (PON1) enzyme was purified from human serum by simple chromatographic methods with 4095.24 EU mg^-1 protein specific activity. The inhibitory activities of gadoteric acid, gadopentetic acid, gadoxetate disodium, and gadodiamide were investigated on PON1 activity of the enzyme. IC₅₀ values were found in the range of 51.28 ± 0.14 to 285.80 ± 0.96 mM. K_i constants were found as 67.95 ± 0.60 mM, 104.97 ± 0.96 mM, 202.33 ± 1.75 mM, and 299.43 ± 2.64 mM for gadoteric acid, gadopentetic acid, gadoxetate disodium, and gadodiamide, respectively. While the inhibition types are determined as competitive of gadoxetate disodium and gadodiamide by the Lineweaver-Burk curves, it was noncompetitive for other compounds. In addition, the molecular docking analyses of gadoxetate disodium and gadodiamide were carried out to understand the binding interactions on the active site of the PON1 enzyme. The structure-activity relationship (SAR) of the drugs was established on the basis of different substituents and their positions in the compounds.

Thiol/Disulfide homeostasis in patients with rheumatoid arthritis

BACKGROUND

Oxidative stress may play an important role in rheumatoid arthritis (RA) etiopathogenesis. The thiol group is a very strong antioxidant. In this study, we aimed to investigate the presence of oxidative stress in patients with RA by evaluating thiol/disulfide homeostasis.

MATERIAL AND METHODS

A total of 50 female RA patients and 50 healthy female controls were included in this study. Thiol and disulfide values were calculated utilizing novel methods.

RESULTS

Native thiol (p < 0.001) and total thiol (p < 0.001) levels of RA patients were significantly lower compared to values in the control group. However, the disulfide (p < 0.001) levels of RA patients were strongly higher than in healthy individuals. A negative correlation was found between thiol and disease activity score-28 among the patients, whereas a positive correlation was found between disulfide and disease activity score-28 among the patients.

CONCLUSION

We found that the thiol-disulfide rate deteriorated in RA patients, with the proportion of disulfide increasing. There is a strong correlation between the decrease in thiol levels, increase in disulfide levels and the disease activity scores.

Diagnostic value of anti-citrullinated fibrinogen antibody in rheumatoid arthritis: A meta-analysis

AIM

To evaluate the overall diagnostic value of anti-citrullinated fibrinogen (ACF) antibody in patients with rheumatoid arthritis (RA).

METHODS

Published studies were systematically retrieved from PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), Wan Fang, China Biology Medicine (CBM) disc, and Chinese VIP databases. QUADAS-2 tool was applied to evaluate the quality of eligible studies. Subgroup analysis and meta-regression were used to explore the sources of heterogeneity. Egger's test was used to evaluate for the presence of publication bias.

RESULTS

Seven studies were included in this meta-analysis. The pooled sensitivity, specificity, pooled positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio of ACF were 0.61 (95% CI: 0.57-0.64), 0.93 (95% CI: 0.92-0.94), 9.33 (95% CI: 5.15-16.92), 0.39 (95% CI: 0.30-0.53) and 24.58 (95% CI: 11.47-52.64), respectively. The area under the curve was 0.8018. The results of subgroup analysis and meta-regression indicated that the factors we analyzed might not be the leading causes of heterogeneity. No significant publication bias was found.

CONCLUSION

The ACF antibody had a moderate diagnostic accuracy on RA.

Correlation of High-Density Lipoprotein-Associated Paraoxonase 1 Activity With Systemic Inflammation, Disease Activity, and Cardiovascular Risk Factors in Psoriatic Disease

OBJECTIVE

To compare the activity of high-density lipoprotein (HDL)-associated paraoxonase 1 (PON1) in patients with psoriasis (PsO) and patients with psoriatic arthritis (PsA), and to evaluate the association of PON1 activity with the extent of disease activity and severity of the cardiovascular disease (CVD) burden in these patients.

METHODS

Serum levels of paraoxonase and arylesterase activity (both measures of PON1 function in humans) were measured in patients with PsA (n = 198, 51.0% male) and patients with PsO (n = 145, 50.3% male) who were enrolled in a longitudinal psoriatic disease biorepository. Data on PsA disease activity (using the Disease Activity Score in 28 joints [DAS28], Clinical Disease Activity Index, and painful/swollen joint counts), preexistent CVD and CVD risk factors (including diabetes, dyslipidemia, hypertension, and smoking), Framingham Risk Scores for CVD, quality of life measures, and laboratory test findings (erythrocyte sedimentation rate, C-reactive protein level, and lipid profiles) were recorded.

RESULTS

Serum arylesterase activities were significantly lower in patients with PsO and patients with PsA (mean ± SD 111.1 ± 25.5 μmoles/minute/ml and 124.4 ± 33.4 μmoles/minute/ml, respectively) compared to healthy controls (144.3 ± 33.4 μmoles/minute/ml) (each P < 0.001 versus healthy controls). Serum arylesterase activity decreased in parallel with increasing levels of disease activity (DAS28 scores, P = 0.012), older age (P = 0.013), higher body mass index (P = 0.042), greater incidence of metabolic syndrome (P = 0.004) and hypertension (P = 0.014), and worsening Framingham Risk Scores (P = 0.001). However, no correlation was seen between serum arylesterase activity and the extent of disease activity or CVD burden in patients with PsO. Serum paraoxonase activity trended lower both in patients with PsO and in patients with PsA (each P = 0.073 versus healthy controls). However, no association was seen between serum paraoxonase activity and the extent of disease activity or CVD burden in either of the patient cohorts.

CONCLUSION

PON1 activity is decreased in psoriatic diseases. In the PsA cohort, decreases in arylesterase activity correlated with increasing severity of joint disease and CVD burden. Arylesterase activity, as compared to paraoxonase activity, appeared to serve as a more sensitive predictor of preexisting CV risk factors in the PsA cohort. However, this correlation was not observed in the PsO population.

A Retrospective Study: The Significance of Combined Testing of Serum Markers for Diagnosis of Rheumatoid Arthritis

Background

There have been few studies on the value of various antibody combinations in rheumatoid arthritis (RA) diagnosis, and a lack of studies with large sample sizes, especially in the Chinese population. This study retrospectively evaluated the diagnostic value of a combined assay of five auto-antibodies [anti-cyclic citrullinated peptide (anti-CCP), anti-keratin (AKA), anti-RA 33, glucose-6-phosphate isomerase (GPI), and rheumatoid factor (RF)] for RA.

Material/Methods

Data were obtained from 5,725 patients with rheumatic diseases in Southwest Hospital of Chongqing from 2011 to 2014. Detection of the five serological markers was performed for all study patients using the appropriate method for each antibody.

Results

It was found that of the 5,725 patients, the positive rates for RF, anti-CCP, anti-RA 33, AKA, and GPI were 52.5%, 40.1%, 12.8%, 12.0%, and 50.0% respectively. In RA patients, the positive rates were 83.3%, 68.5%, 16.6%, 20.8%, and 77.9% respectively, which were all significantly higher than those detected in patients with the other diseases (p<0.01). The areas under the receiver operator characteristic (ROC) curve for RF, anti-CCP, anti-RA 33, AKA, and GPI were 0.857, 0.831, 0.528, 0.602, and 0.822 respectively, indicating that these five serological markers display favorable diagnostic value for RA. There were positive correlations between anti-CCP antibody and RF and GPI (p<0.01) and between RF and GPI (p<0.01), but no correlation between anti-RA 33 and AKA (p<0.01). The specificity of the combination of anti-CCP, AKA, and GPI was 100% for RA diagnosis.

Conclusions

The combined assay of serological markers significantly improved the diagnostic specificity for RA. The diagnostic value of RF for RA was the highest and the combined assay for anti-CCP, AKA, and GPI had the highest specificity for RA diagnosis.

Antibodies to paraoxonase 1 are associated with oxidant status and endothelial activation in rheumatoid arthritis

Anti-paraoxonase 1 (PON1) antibodies could be a potential missing link between oxidative status, inflammation and cardiovascular disease (CVD) in rheumatoid arthritis (RA) patients. Therefore, they could represent an emerging clinical biomarker of CV risk in this condition.

Therapeutic potential of folic acid supplementation for cardiovascular disease prevention through homocysteine lowering and blockade in rheumatoid arthritis patients

Rheumatoid arthritis (RA) is a chronic inflammatory disease that preferentially affects joints, and characterized by an approximately two-fold increased risk of cardiovascular diseases compared with the general population. Beyond classical cardiovascular risk factors, systemic inflammatory markers are primarily involved. Hence, anti-inflammatory strategies such as homocysteine-lowering interventions are warranted. Indeed, hyperhomocysteinemia is commonly found in RA patients as a result of both genetic and non-genetic factors including older age, male gender, disease-specific features and disease-modifying antirheumatic drugs. Most importantly in the pathophysiology of hyperhomocysteinemia and its related cardiovascular diseases in RA, there is a bi-directional link between immuno-inflammatory activation and hyperhomocysteinemia. As such, chronic immune activation causes B vitamins (including folic acid) depletion and subsequent hyperhomocysteinemia. In turn, hyperhomocysteinemia may perpetrate immuno-inflammatory stimulation via nuclear factor ƙappa B enhancement. This chronic immune activation is a key determinant of hyperhomocysteinemia-related cardiovascular diseases in RA patients. Folate, a homocysteine-lowering therapy could prove valuable for cardiovascular disease prevention in RA patients in the near future with respect to homocysteine reduction along with blockade of subsequent oxidative stress, lipid peroxidation, and endothelial dysfunction. Thus, large scale and long term homocysteine-lowering clinical trials would be helpful to clarify the association between hyperhomocysteinemia and cardiovascular diseases in RA patients and to definitely state conditions surrounding folic acid supplementation. This article reviews direct and indirect evidence for cardiovascular disease prevention with folic acid supplementation in RA patients.

Ocular manifestations of rheumatoid arthritis and their correlation with anti-cyclic citrullinated peptide antibodies

Purpose

To study the ocular manifestations of rheumatoid arthritis and to correlate the role of anti-cyclic citrullinated peptide antibody (anti-CCP antibody) with the ocular manifestations.

Methods

Three-hundred and ninety-two eyes of the 196 rheumatoid arthritis patients who attended the ophthalmology outpatient department underwent a detailed ocular examination using slit lamp biomicroscopy and ophthalmoscopy. The tear function of all the patients was assessed using Schirmer’s test, tear film break-up time and ocular surface staining. The anti-CCP antibody titers for all the rheumatoid arthritis patients were estimated using enzyme-linked immunosorbent assay tests.

Results

Seventy-seven patients (135 eyes, 39%) out of the 196 patients studied had ocular manifestations typical of rheumatoid arthritis. Dry eye was the most common manifestation (28%, 54 patients). Of the patients, 78% was females (60 patients). The mean duration of rheumatoid arthritis in patients with ocular manifestations was 5.4±2.7 years and without ocular manifestations was 2.1±1.6years. Three percent of the patients had episcleritis (six patients). Scleritis was present in 2% of the patients (four patients). Peripheral ulcerative keratitis and sclerosing keratitis was present in 1% of the population each (two patients each). Eighty-five percent (66 patients) had bilateral manifestations 15% (eleven patients) had unilateral manifestations. There was a strong association between the presence of anti-CCP antibodies and ocular manifestations of rheumatoid arthritis which was shown by the statistically significant P-value of <0.0001.

Conclusion

Ocular manifestations are a significant part of the extra-articular manifestation of rheumatoid arthritis. Dry eye was the most common ocular manifestation. There was a statistically significant association between the presence of anti-CCP antibodies specific to rheumatoid arthritis and the ocular manifestations.