Serum lipid levels in Sjögren's syndrome

Lipid Metabolism: An Emerging Player in Sjögren's Syndrome

Sjögren's syndrome (SS) is a chronic autoimmune disorder that primarily affects the exocrine glands. Due to the intricate nature of the disease progression, the exact mechanisms underlying SS are not completely understood. Recent research has highlighted the complex interplay between immune dysregulation and metabolic abnormalities in inflammatory diseases. Notably, lipid metabolism has emerged as a crucial factor in the modulation of immune function and the progression of autoimmune diseases, including SS. This review explores the prevalence of dyslipidemia in SS, emphasizing its role in the onset, progression, and prognosis of the disease. We specifically described the impact of altered lipid metabolism in exocrine glands and its association with disease-specific features, including inflammation and glandular dysfunction. Additionally, we discussed the potential clinical implications of lipid metabolism regulation, including the role of polyunsaturated fatty acids (PUFAs) and their deficits in SS pathogenesis. By identifying lipid metabolism as a promising therapeutic target, this review highlights the need for further research into lipid-based interventions for the management of SS.

Associations between metabolic disorders and Sjögren's disease

Sjögren's disease (SjD) is a systemic autoimmune disorder characterized by dry eyes and mouth caused by chronic inflammation and is often accompanied by various extra-glandular manifestations, including fatigue and diffuse pain. Although the pathogenesis of the disease remains elusive, several factors (e.g. environmental, genetic and hormonal factors, abnormal metabolic status) are associated with this condition. Accumulating evidence suggests a potential role of cholesterol metabolism in immune and non-immune modulation in various diseases. In this review, we summarize the current findings on the associations between cholesterol metabolism and SjD.

Dysregulated serum lipid profile is associated with inflammation and disease activity in primary Sjögren's syndrome: a retrospective study in China

PURPOSE

To investigate the relationship between the lipid profiles of patients with primary Sjögren's syndrome (pSS) and other clinical characteristics, laboratory examination, disease activity, and inflammatory factors. In addition, the risk factors for hyperlipidemia-related complications of pSS and the effect of hydroxychloroquine (HCQ) usage on the lipid profile were incorporated into this study.

METHODS

This is a single-center, retrospective study that included 367 patients who were diagnosed with pSS at Tongji Hospital, School of Medicine, Tongji University, China from January 2010 to March 2022. Initially, demographic information, clinical characteristics, medication records, and complications of the patients were gathered. A case-control analysis compared the 12 systems involvement (ESSDAI domain), clinical symptoms, and laboratory tests between pSS patients with and without dyslipidemia. A simple linear regression model was employed to investigate the relationship between serum lipid profile and inflammatory factors. Logistics regression analysis was performed to assess variables for hyperlipidemia-related complications of pSS. The paired t-test was then used to evaluate the improvement in lipid profile among pSS patients.

RESULTS

48.7 % of all pSS patients had dyslipidemia, and alterations in lipid levels were related to gender, age, and smoking status but not body mass index (BMI). Dyslipidemia is more prevalent in pSS patients who exhibit heightened autoimmunity and elevated levels of inflammation. Higher concentrations of multiple highly inflammatory factors correlate with a more severe form of dyslipidemia. Non-traditional cardiovascular risk factors may contribute to hyperlipidemia-related complications of pSS, such as increased, low complement 3 (C3) and low C4. According to our study, HCQ usage may protect against lipid-related disease in pSS.

CONCLUSION

Attention should be paid to the dyslipidemia of pSS. This research aims to clarify the population portrait of pSS patients with abnormal lipid profiles and provides insights into the correlation between metabolism and inflammation in individuals with pSS and the potential role they play in the advancement of the disease. These findings provide novel avenues for further understanding the underlying mechanisms of pSS pathogenesis.

Risk factors for cardiovascular disease in primary Sjögren's syndrome (pSS): a 20-year follow-up study

INTRODUCTION

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease characterized by a chronic grade of inflammation. Cardiovascular events represent the major causes of morbidity and mortality in patients with inflammatory rheumatic diseases; however, the significance and prevalence of cardiovascular disease in patients with pSS remain unclear.

OBJECTIVE

To determine the clinical significance of cardiovascular disease in pSS and analyze the risk of cardiovascular disease according to glandular/extraglandular involvement and positivity to anti-Ro/SSA and/or anti-La/SSB autoantibodies.

METHODS

A retrospective study including patients diagnosed with pSS fulfilling the 2016 ACR/EULAR classification criteria was followed and evaluated in our outpatient clinic between 2000 and 2022. The prevalence of cardiovascular risk factors with pSS was evaluated, and a possible association with clinical and immunological characteristics, the treatments received, and the impact on cardiovascular disease were determined. Univariate and multivariate regression analyses were performed in an attempt to determine potential risk factors associated with cardiovascular involvement.

RESULTS

A total of 102 pSS patients were included. Eighty-two percent were female, with a mean age of 65±24 years and a disease duration of 12.5 ±6 years. Thirty-six patients (36%) had at least one cardiovascular risk factor. Arterial hypertension was diagnosed in 60 (59%) patients, dyslipidemia in 28 (27%), diabetes in 15 (15%), obesity in 22 (22%), and hyperuricemia in 19 (18%). History of arrhythmia was found in 25 (25%), conduction defects in 10 (10%), arterial peripheral vascular disease in 7 (7%), venous thrombosis in 10 (10%), coronary artery disease in 24 (24%), and cerebrovascular disease in 22 (22%) of patients. Patients with extraglandular involvement had a higher prevalence of arterial hypertension (p=0.04), dyslipidemia (p=0.003), LDL mean values (p=0.038), hyperuricemia (p=0.03), and coronary artery disease (p=0.01) after adjusting for age, sex, disease duration, and the significant variables in the univariate analysis. Patients with Ro/SSA and La/SSB autoantibodies had a substantially higher risk of hyperuricemia (p=0.01), arrhythmia (p=0.01), coronary artery disease (p=0.02), cerebrovascular disease (p=0.02), and venous thrombosis (p =0.03). In the multivariate logistic regression analysis, higher odds of cardiovascular risk factors were associated with extraglandular involvement (p=0.02), treatment with corticosteroids (p=0.02), ESSDAI>13 (p=0.02), inflammatory markers including ESR levels (p 0.007), and serologic markers such as low C3 levels (p=0.03) and hypergammaglobulinemia (p=0.02).

CONCLUSIONS

Extraglandular involvement was associated with a higher prevalence of arterial hypertension, dyslipidemia, hyperuricemia, and coronary artery disease. Anti-Ro/SSA and anti-La/SSB seropositivity was associated with a higher prevalence of cardiac rhythm abnormalities, hyperuricemia, venous thrombosis, coronary artery disease, and cerebrovascular disease. Raised inflammatory markers, disease activity measured by ESSDAI, extraglandular involvement, serologic markers including hypergammaglobulinemia and low C3, and treatment with corticosteroids were associated with a higher risk for cardiovascular comorbidities. Key Points • Patients with pSS are vulnerable to cardiovascular risk factors. There is an interconnection between extraglandular involvement, disease activity, inflammatory markers, and cardiovascular risk comorbidities. • Anti-Ro/SSA and anti-La/SSB seropositivity was associated with a higher frequency of cardiac conduction abnormalities, coronary artery disease, venous thrombosis, and stroke. • Hypergammaglobulinemia, elevated ESR, and low C3 are associated with a higher prevalence of cardiovascular comorbidities. • Valid risk stratification tools to help with prevention and consensus on the management of CVDs in pSS patients are warranted.

PPARs/macrophages: A bridge between the inflammatory response and lipid metabolism in autoimmune diseases

Autoimmune diseases (AIDs) are a collection of pathologies that arise from autoimmune reactions and lead to the destruction and damage of the body's tissues and cellular components, ultimately resulting in tissue damage and organ dysfunction. The anti-inflammatory effects of the peroxisome proliferator-activated receptor (PPAR), a pivotal regulator of lipid metabolism, are crucial in the context of AIDs. PPAR mitigates AIDs by modulating macrophage polarization and suppressing the inflammatory response. Numerous studies have demonstrated the crucial involvement of lipid metabolism and phenotypic switching in classically activated (M1)/alternatively activated (M2)-like macrophages in the inflammatory pathway of AIDs. However, the precise mechanism by which PPAR, a critical mediator between of lipid metabolism and macrophage polarization, regulates macrophage polarization remains unclear. This review aimed to clarify the role of PPAR and macrophages in the triangular relationship among AIDs, lipid metabolism, and inflammatory response, and aims to summarize the mechanism of the PPAR-mediated macrophage activation and polarization, which impacts the progression and development of AIDs.

Exploring the Link between Plasma Levels of PCSK9, Immune Dysregulation and Atherosclerosis in Patients with Primary Sjögren's Syndrome

Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates lipid metabolism contributing to cardiovascular (CV) risk in the general population. The relationship between PCSK9 and CV risk in systemic autoimmune diseases has been poorly explored. We investigated the association between plasma PCSK9, measures of immune-inflammatory status and markers of atherosclerosis in 52 consecutive patients with primary Sjögren's syndrome (pSS) in comparison to healthy controls (HCs). Median plasma PCSK9 levels were significantly higher in pSS patients versus HCs (162 (79-255) vs. 53 (39-99) ng/mL). Significantly higher prevalence of subclinical atherosclerosis and lower of dyslipidaemia (61% vs. 85%, p = 0.042) characterized pSS patients versus HCs. In pSS, no significant correlation emerged between PCSK9 and disease activity, atherosclerosis and lipid levels. In HCs, PCSK9 significantly correlated with lipid levels and atherosclerosis. Interestingly, significantly higher PCSK9 levels were found in HCs with high-to-very-high as compared to low-to-moderate CV risk (p = 0.018) while a non-significant trend towards higher PCSK9 levels was detected in pSS patients with low-to-moderate as compared to high-to-very-high CV risk (p = 0.060). This is the first demonstration that pSS patients, despite lower prevalence of dyslipidaemia and higher CV risk profile, are characterized by a 3-fold increase in PCSK9 levels in comparison to HCs. As PCSK9 does not correlate with measures of CV risk, its role in CV morbidity in pSS needs further investigation.

Cardiac Manifestations of Sjogren's Syndrome: A Review of Literature

Sjogren's syndrome (SS) is a chronic inflammatory disorder of the exocrine glands. It is characterized by a lymphocytic infiltrate in the lacrimal and salivary glands causing keratoconjunctivitis sicca and xerostomia. Extra-glandular involvement may be present in about one-third of patients with primary Sjogren's syndrome (pSS). The most commonly affected organs are the thyroid, lungs, gastrointestinal tract, kidneys, skin, and nervous system. Cardiac manifestations of Sjogren's syndrome are rare and not well-described in the current literature. Most of the evidence is present in the form of case reports and small case series. However, recent studies have shown that patients with Sjogren's syndrome (SS) seem to have a greater overall risk of cardiovascular (CV) events. Although not conventionally considered a feature of the disease, cardiac manifestations can lead to increased morbidity and mortality in this patient population. In this review article, we study the association between cardiac diseases and primary Sjogren's syndrome.

Plasma lipidomics of primary biliary cholangitis and its comparison with Sjögren's syndrome

Background

Abnormal lipid metabolism is common in patients with primary biliary cholangitis (PBC). PBC and Sjögren's syndrome (SS) frequently coexist in clinical practice; however, the lipid characteristics of both diseases are unknown. Therefore, we aimed to analyze the plasma lipid profiles of both diseases.

Methods

Plasma samples from 60 PBC patients, 30 SS patients, and 30 healthy controls (HC) were collected, and untargeted lipidomics was performed using ultrahigh-performance liquid chromatography high-resolution mass spectrometry. Potential lipid biomarkers were screened through an orthogonal projection to latent structure discriminant analysis and further evaluated using receiver operating characteristic (ROC) analysis.

Results

A total of 115 lipids were differentially upregulated in PBC patients compared with HC. Seventeen lipids were positively associated with the disease activity of PBC, and ROC analysis showed that all of these lipids could differentiate between ursodeoxycholic acid (UDCA) responders and UDCA non-responders. The top six lipids based on the area under the curve (AUC) values were glycerophosphocholine (PC) (16:0/16:0), PC (18:1/18:1), PC (42:2), PC (16:0/18:1), PC (17:1/14:0), and PC (15:0/18:1). In comparison with SS, 44 lipids were found to be differentially upregulated in PBC. Additionally, eight lipids were found to have a good diagnostic performance of PBC because of the AUC values of more than 0.9 when identified from SS and HC groups, which were lysophosphatidylcholines (LysoPC) (16:1), PC (16:0/16:0), PC (16:0/16:1), PC (16:1/20:4), PC (18:0/20:3), PC (18:1/20:2), PC (20:0/22:5), and PC (20:1/22:5).

Conclusion

Our study revealed differentially expressed lipid signatures in PBC compared with HC and SS. PC is the main lipid species associated with disease activity and the UDCA response in patients with PBC.

Subclinical atherosclerosis in primary Sjögren's syndrome: comparable risk with diabetes mellitus

OBJECTIVES

It has been found that the risk of subclinical atherosclerosis in some connective tissue diseases (CTDs) was equivalent to type 2 diabetes mellitus (T₂DM). There is no clinical study focusing on the differences of subclinical atherosclerosis between primary Sjögren's syndrome (pSS) and T₂DM. Our aim is to investigate the prevalence of subclinical atherosclerosis in pSS patients, compare the differences in subclinical atherosclerosis between pSS and T₂DM patients, and determine the risk factors of subclinical atherosclerosis.

METHOD

A retrospective case-control study of 96 patients with pSS, 96 age- and sex-matched T₂DM patients and healthy individuals underwent evaluation, including clinical data and carotid ultrasound examination. Univariate and multivariate models were used to explore the related factors of carotid intima-media thickness (IMT) and carotid plaque.

RESULTS

Increased IMT scores were detected in patients with pSS and T₂DM compared to controls. The percentages of carotid IMT were detected in 91.7% of pSS and 93.8% of T₂DM patients versus 81.3% in the controls. Carotid plaques were detected in 82.3%, 82.3% and 66.7% of pSS, T₂DM, and controls, respectively. Age and the presence of pSS and T₂DM emerged as risk factors for IMT (adjusted OR = 1.25, 4.40, and 9.92, respectively). In addition, age, total cholesterol, and the presence of pSS and T₂DM emerged as risk factors for carotid plaque (adjusted OR = 1.14, 1.50, 4.18, and 3.79, respectively).

CONCLUSIONS

The prevalence of subclinical atherosclerosis in pSS patients was increased, which was comparable to that in T₂DM patients. The presence of pSS is associated with subclinical atherosclerosis. Key Points • The prevalence of subclinical atherosclerosis is higher in primary Sjögren' s syndrome. • The risk of subclinical atherosclerosis is similar in primary Sjögren's syndrome and diabetes mellitus patients. • Advanced age was an independent predictor of carotid IMT and plaque formation in primary Sjögren's syndrome. • Primary Sjögren's syndrome and diabetes mellitus are associated with atherosclerosis.

Cardiovascular Involvement in Sjögren’s Syndrome

Sjögren Syndrome (SS) seems to be associated with a greater “overall risk” of cardiovascular (CV) and cerebrovascular events. Although not conventionally considered a feature of the disease, CV events represent a major burden in SS patients. CV risk is the consequence of a complex combination of multiple factors, including traditional risk factors and disease-related mechanisms. A complex relationships between disease-related features, endothelial dysfunction and traditional risk factor has been suggested. Several drugs are available for treating the systemic manifestations of SS, however they have shown positive effects on different outcomes of the disease, but until today the data on the role of these drugs on CV events are scarse. Given these data, the aim of this review was to evaluate the risk of CV risk in primary SS and the effect of the drugs on this manifestation.

Comorbidities (excluding lymphoma) in Sjögren's syndrome

The information about comorbidities (excluding lymphoma) in primary Sjögren's syndrome (pSS) is relatively scarce. Cardiovascular disease, infections, musculoskeletal conditions or malignancy are likely the most relevant comorbid conditions in pSS. Different infections (particularly oral candidal infections) and fibromyalgia are extremely frequent in the daily clinical practice. On the other hand, the incidence of cardiovascular events and cancer in pSS is low, so information about them comes from large epidemiological studies or meta-analysis. For this reason, preclinical vascular disease is investigated by different techniques, demonstrating the presence of early atherosclerosis in pSS patients. Coronary events could be slightly more frequent in pSS than in the general population. The overall risk of malignancy in pSS patients seems to be slightly increased, likely due to excess occurrence of lymphoma. An association between pSS and thyroid cancer might exist, although it should be confirmed by further investigations.

Clinical Characteristics and Prognosis of Concomitant Primary Biliary Cholangitis and Autoimmune Diseases: A Retrospective Study

Objectives

Diagnosis and treatment of primary biliary cholangitis (PBC) are often complicated by hepatic and/or extrahepatic manifestations, which in turn affect the natural course and prognosis of PBC. This study evaluated the clinical characteristics and prognosis of PBC co-occurring with intrahepatic and extrahepatic autoimmune disease (AID).

Methods

Clinical data of patients with PBC who were admitted to the Beijing Ditan Hospital from September 2008 to December 2014 were retrospectively reviewed, assessed for other autoimmune diseases, and analyzed statistically. All patients received ursodeoxycholic acid (UDCA) treatment.

Results

Data from 505 patients were evaluated. Approximately 35.0% of patients had at least one additional AID. AIDs included Sjögren's syndrome (SS; 26.3%), autoimmune hepatitis (AIH; 7.1%), rheumatoid arthritis (RA; 1.4%), hypothyroidism (0.8%), Graves's thyroiditis (0.6%), systemic lupus erythematosus (SLE; 0.4%), and Hashimoto's thyroiditis (0.2%). No differences in response rates of UDCA were found between the PBC group and the PBC-SS group or PBC complicated with AID group (both P > 0.05). White blood cell (WBC, RR = 1.072, 95% CI: 1.016-1.130, P=0.011), platelet counts (PLT, RR = 0.995, 95% CI: 0.992-0.998, P=0.003), and prothrombin time and international normalized ratio (PT/INR, RR = 1.799, 95% CI: 1.010-3.206, P=0.046) were independent prognostic factors in patients with PBC. The overall survival time of patients in PBC-AIH and PBC-SS groups was shorter than that of those with PBC (P < 0.001).

Conclusions

AIH was the most common in hepatic comorbidity. SS was the most frequent extrahepatic comorbidity. WBC, PLT, and PT/INR were independent prognostic factors in patients with PBC. AID coexisted with PBC impaired patients' survival.

The Evaluation of Serum Lipids Profile in Patients with Pemphigus Vulgaris: A Case-Control Study

Background

Pemphigus vulgaris (PV) is a chronic autoimmune disease. Dyslipidemia, increased risk of atherosclerosis and higher cardiovascular morbidity, and mortality have been reported in several autoimmune conditions. It has been hypothesised that there might be an association between dyslipidemia and PV. Therefore, the objective of this study was to compare the serum lipid profile of patients with PV with healthy controls.

Methods

This case-control study was carried out on 113 patients with PV and 100 healthy controls. Total cholesterol, high-density lipoprotein (HDL) and triglycerides (TG) levels were measured and low-density lipoprotein (LDL), non-HDL cholesterol (non-HDL-C) and atherogenic index of plasma (AIP) were calculated. Chi-squared test and independent Student t-test (or their alternatives) were used for group comparison.

Results

The mean age and BMI of patients and controls were 47.7 ± 14.5 and 28 ± 6.2 and, 44.5 ± 18.5 and 25.5 ± 5.1, respectively. Total cholesterol, LDL, HDL, non-HDL-C and TG were statistically different between the two groups (P values < 0.001; < 0.001; < 0.001; < 0.001 and 0.021, respectively). However, AIP was not significantly different (P-value = 0.752).

Conclusion

The serum lipid profile was significantly higher in PV patients compared to healthy controls. Therefore, PV patients may be more prone to develop atherosclerosis and this finding can be important in the overall management of these patients.

Pharmacological management of cardiovascular risk in chronic inflammatory rheumatic diseases

INTRODUCTION

Cardiovascular comorbidity is a major burden in patients with chronic inflammatory rheumatic diseases and a significant determinant of their outcome. In addition to optimal management of the underlying inflammatory condition according to current guidelines, individual cardiovascular risk factors, particularly dyslipidaemia, hypertension, and impaired glucose tolerance should be assessed regularly and guide risk stratification and requirement for treatment.

AREAS DISCUSSED

We critically reviewed manuscripts and guidelines on the pharmacological management of dyslipidaemia, hypertension, and diabetes in patients with chronic inflammatory rheumatic diseases (PubMed, MEDLINE, EMBASE, Scopus, Web of Science and Google Scholar, up to 1 March 2020). Lifestyle changes are of paramount importance for the management of these risk factors. In the current narrative review, we discuss pharmacological therapies available and emerging therapies aiming to help patients achieve recommended targets, depending on their individual risk.

EXPERT OPINION

CVD risk is increased in people with chronic inflammatory rheumatic diseases. Cardiovascular risk factor management is an essential part of their care. Although relevant guidance exists, there are still major gaps in knowledge and risk factor management implementation in these patient groups. Some practical guidance based on our interpretation of existing data and experience in the field is provided in this review.

Low high-density lipoprotein cholesterol and high triglycerides lipid profile in neuromyelitis optica spectrum disorder: Associations with disease activity and disability

BACKGROUND

Altered lipid metabolism is a feature of systemic autoimmune diseases. Dyslipidemia is associated with the disease activity and progression in patients with multiple sclerosis. However, in neuromyelitis optica spectrum disorder (NMOSD), changes in the lipid profile and the associations between specific lipid levels and disease activity/disability are unknown.

METHODS

Serum samples (N = 148) were collected from 53 patients with aquaporin-4 (AQP4)-positive NMOSD when they were not treated with lipid lowering agents. Fasting lipid (total cholesterol, triglyceride [TG], high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol) levels were compared between 39 patients with NMOSD, not taking steroids, and 142 age-, sex-, and body mass index-matched healthy controls. In addition, we analyzed the differences in the lipid profile between attack and remission samples and the associations between lipid profiles and clinical outcome in all 148 samples from 53 patients. The generalized estimating equation was used.

RESULTS

Patients with NMOSD showed lower HDL-C and higher TG levels compared to healthy controls (p = 0.017 and p < 0.001, respectively). HDL-C level was significantly lower during attack than remission (β = -7.851; p = 0.035), and TG level had positive correlation with EDSS scores (β = 0.014; p = 0.002) regardless of disease activity status. However, enhanced lesions on magnetic resonance imaging were not associated with lipid profiles.

CONCLUSION

Dyslipidemia with low HDL-C and high TG correlated disease activity and disability in AQP4-positive NMOSD. It remains to be elucidated whether altered lipid metabolism contributes to deleterious immune response, possibly through inflammation, or is secondary to neurological disability in NMOSD.

Impaired HDL Function Amplifies Systemic Inflammation in Common Variable Immunodeficiency

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency, characterized by inadequate antibody responses and recurrent bacterial infections. Paradoxically, a majority of CVID patients have non-infectious inflammatory and autoimmune complications, associated with systemic immune activation. Our aim was to explore if HDL, known to have anti-inflammatory properties, had impaired function in CVID patients and thereby contributed to their inflammatory phenotype. We found reduced HDL cholesterol levels in plasma of CVID patients compared to healthy controls, particularly in patients with inflammatory and autoimmune complications, correlating negatively with inflammatory markers CRP and sCD25. Reverse cholesterol transport capacity testing showed reduced serum acceptance capacity for cholesterol in CVID patients with inflammatory and autoimmune complications. They also had reduced cholesterol efflux capacity from macrophages to serum and decreased expression of ATP-binding cassette transporter ABCA1. Human HDL suppressed TLR2-induced TNF release less in blood mononuclear cells from CVID patients, associated with decreased expression of transcriptional factor ATF3. Our data suggest a link between impaired HDL function and systemic inflammation in CVID patients, particularly in those with autoimmune and inflammatory complications. This identifies HDL as a novel therapeutic target in CVID as well as other more common conditions characterized by sterile inflammation or autoimmunity.

Epidermal Fatty Acid-Binding Protein: A Novel Marker in the Diagnosis of Dry Eye Disease in Sjögren Syndrome

Purpose: Sjögren syndrome (SS) is a chronic inflammatory autoimmune disease of the lacrimal and salivary glands. This study compared the concentrations of epidermal fatty-acid binding protein (E-FABP) in the saliva, serum, and tears of SS patients with dry eye and dry mouth, with those of healthy adults to investigate the usefulness of E-FABP as a diagnostic marker for SS. Design: Prospective, observational case series. Participants: The subjects were 11 new patients with untreated Sjogren syndrome and 12 healthy control individuals. Methods: The diagnosis of SS was in accordance with the Ministry of Health, Labour and Welfare (Japan) Diagnostic Criteria (1999). Saliva, serum, and tear specimens were collected during internal medicine, dental, and ophthalmological examinations. The ophthalmological tests included the Dry Eye-related Quality of life Score (DEQS), tear break-up time (BUT), vital staining with fluorescein (FS) and lissamine green (LG), and the Schirmer test-1. The E-FABP concentration in the tears, saliva, and serum was measured by enzyme-linked immunosorbent assay (ELISA). Main outcome measure: The E-FABP concentrations were compared between patients and controls. Results: There were significant differences between the patient and healthy control groups in all ophthalmological test results. There were no significant differences between the groups in the E-FABP concentrations in the saliva (p = 0.1513) or the serum (p = 0.4799), but the E-FABP concentration in the tears significantly differed between groups. The E-FABP concentration in tears tended to be significantly lower in patients with SS (mean, 323.5 ± 325.6 pg/mL) than healthy control subjects (mean, 4076 pg/mL; p = 0.0136). The E-FABP concentration in tears significantly correlated with the results of dry eye parameters. Conclusion: The E-FABP concentration in tears appears to be related to ocular surface epithelial damage and tear stability and may be a promising novel biomarker in the diagnosis of SS.

Evaluation of subclinical atherosclerosis by ultrasound radiofrequency data technology in patients with primary Sjögren's syndrome

Primary Sjögren's syndrome (pSS) is a chronic inflammatory autoimmune disease, and inflammation is highly associated with atherosclerosis and increased cardiovascular risk. Carotid intima-media thickness (CIMT) and arterial stiffness measurements are commonly used to detect subclinical atherosclerosis. The aim of this study was to non-invasively demonstrate the presence of subclinical atherosclerosis in patients with pSS through these measurements, using ultrasound (US) radiofrequency (RF) data technology. 30 pSS patients as the study group and 30 age-and sex-matched healthy volunteers as the control group were included in this study. The age of the participants in the entire sample ranged from 18 to 60 years, and no primary cardiovascular risk factors were present, such as diabetes mellitus, hypertension, hyperlipidemia, or obesity. The participants in the study and control groups were evaluated with doppler ultrasonography. Arterial stiffness and CIMT measurements were made from the bilateral common carotid arteries (CCA) using US RF data technology. No statistically significant difference was identified between the patients with pSS and the controls in terms of the right, left, and mean CCA IMT; the right side distensibility coefficient (DC) and compliance coefficient (CC); or the right- and left-side α and β stiffness indices values (p > 0.05). Compared to the control subjects, the pSS patients had higher right and left side pulsed wave velocity (PWV), the mean value of the right and the left sides α stiffness index, β stiffness index, and PWV (p < 0.05). The pSS patients' left DC, left CC, and the mean value of the right and left sides DC and CC were lower than controls (p < 0,05). It was found that patients with pSS show evidence of subclinical atherosclerosis. To determine this situation in patients with pSS, CIMT and PWV measurements may serve as a guide. Radiofrequency data technology represents a non-invasive approach to the accurate and quantitative measurement of CIMT elevation and decreases in vascular elasticity.

Increased risk of coronary heart disease among patients with primary Sjögren's syndrome: a nationwide population-based cohort study

To investigate the association between primary Sjögren’s syndrome (pSS) and coronary heart disease (CHD), and the influence of medications for pSS patients on risk of CHD. The authors identified 4175 patients with a new diagnosis of pSS between 2002 and 2013 from the National Health Insurance Research database. The control-to-case ratio was 4:1. The risk and cumulative incidences of CHD were calculated. The adjusted hazard ratio (HR) of CHD for pSS patients was 1.17 (1.03–1.34) after adjusting for age, sex, comorbidities, and medications. The cumulative incidence for CHD in the pSS group was significantly higher than that in the control group (log-rank p < 0.0001). The risk of CHD in pSS patients was increased with age by 4% per year, and 45- to 59-year-olds were at the highest risk (HR = 1.464, 1.195–1.794). The application of corticosteroids (HR = 1.45, 1.07–1.97) as well as NSAIDs (HR = 1.31, 1.05–1.65) both increased the risk of CHD among pSS patients. pSS is associated with an increased risk of subsequent CHD in Taiwan. Primary Sjögren’s syndrome might be an independent risk factor for CHD. Use of corticosteroids and NSAIDs in the treatment of pSS patients increased the risk of developing CHD.

Cardiovascular disease risk burden in primary Sjögren's syndrome: results of a population-based multicentre cohort study

OBJECTIVE

Systemic autoimmune diseases, in particular systemic lupus erythematosus and rheumatoid arthritis, are characterized by a high risk of premature cardiovascular (CV) events. Disease-related characteristics and traditional CV disease risk factors may contribute to atherosclerotic damage. However, there are limited data on the risk of overt CV events in primary Sjögren's syndrome (pSS).

METHODS

We retrospectively analysed a cohort of patients with 1343 pSS. Disease-related clinical and laboratory data, traditional CV disease risk factors and overt CV events were recorded. Prevalence of traditional CV disease risk factors and of major CV events was compared between a subgroup of 788 female patients with pSS aged from 35 to 74 years and 4774 age-matched healthy women.

RESULTS

Hypertension and hypercholesterolaemia were more prevalent, whereas smoking, obesity and diabetes mellitus were less prevalent, in women with pSS than in control subjects. Cerebrovascular events (2.5% vs. 1.4%, P = 0.005) and myocardial infarction (MI) (1.0% vs. 0.4%, P = 0.002) were more common in patients with pSS. In the whole population, central nervous system involvement (odds ratio (OR) 5.6, 95% confidence interval (CI) 1.35-23.7, P = 0.02) and use of immunosuppressive therapy (OR 1.9, 95% CI 1.04-3.70, P = 0.04) were associated with a higher risk of CV events. Patients with leucopenia had a higher risk of angina (P = 0.01).

CONCLUSIONS

pSS is associated with an increased risk of cerebrovascular events and MI. Disease-related clinical and immunological markers may have a role in promoting CV events.

Subclinical atherosclerosis and impaired bone health in patients with primary Sjogren's syndrome: prevalence, clinical and laboratory associations

Introduction

To determine the prevalence and clinical/laboratory associations of subclinical atherosclerosis and impaired bone health in primary Sjogren’s syndrome (SS).

Methods

64 consecutive patients with primary SS, 77 with rheumatoid arthritis (RA) and 60 healthy controls (HC) οf similar age and sex distribution were enrolled. Demographics, clinical/laboratory features, classical risk factors for atherosclerosis and osteoporosis (OP) were recorded. Intima-medial thickness scores (IMT) and carotid/femoral (C/F) plaque formation, as well as bone mineral density (BMD) and fractures were evaluated. Determinants of IMT/BMD levels and the presence of plaque were assessed by univariate and multivariate models. Serum levels of the Wnt signaling mediators Dickkopf-related protein 1(DKK1) and sclerostin were determined in primary SS patients and HC.

Results

Increased arterial wall thickening (IMT > 0.90 mm) and impaired bone health (defined as OP or osteopenia), were detected in approximately two-thirds of primary SS and RA patients, with a mean IMT value being significantly increased compared to HC. The presence of primary SS emerged as an independent risk factor for arterial wall thickening when traditional risk factors for cardiovascular disease (CVD) including age, sex, hypertension, smoking (pack/years), LDL and HDL levels were taken into account in a multivariate model [adjusted OR 95% (CI): 2.8 (1.04-7.54)]. In primary SS, age was revealed as independent predictor of increased IMT scores; age and lymphopenia as well as increased urine pH as independent determinants of C/F plaque formation and OP/osteopenia, respectively. An independent association of OP/osteopenia with plaque formation was observed when independent predictors for both variables were considered, with low DKK1 levels being associated with both plaque formation and lower BMD levels.

Conclusions

Comorbidities such as subclinical atherosclerosis and impaired bone health occur frequently in primary SS, in association with disease related features and traditional risk factors. Wnt signaling mediators are potentially involved in the pathogenesis of both entities.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0613-6) contains supplementary material, which is available to authorized users.

Cardiovascular risk factors in women with primary Sjögren's syndrome: United Kingdom primary Sjögren's syndrome registry results

Objective

To determine the prevalence of traditional cardiovascular risk factors using established definitions in a large cohort of clinically well-characterized primary Sjögren's syndrome (SS) patients and to compare them to healthy controls.

Methods

Data on cardiovascular risk factors in primary SS patients and controls were collected prospectively using a standardized pro forma. Cardiovascular risk factors were defined according to established definitions. The prevalence of cardiovascular risk factors in the primary SS group was determined and compared to that in the control group.

Results

Primary SS patients had a higher prevalence of hypertension (28–50% versus 15.5–25.6%; P < 0.01) and hypertriglyceridemia (21% versus 9.5%; P = 0.002) than age- and sex-matched healthy controls. Furthermore, a significant percentage (56%) of hypertensive patients expected to be on antihypertensive treatment according to best practice was not receiving it.

Conclusion

Primary SS patients are more than 2 times more likely to experience hypertension and hypertriglyceridemia than age- and sex-matched healthy controls. Additionally, hypertension is underdiagnosed and suboptimally treated in primary SS.

Effect of hydroxychloroquine on the lipid profile of patients with Sjögren syndrome

OBJECTIVE

Many studies have highlighted the hypolipidemic action of hydroxychloroquine (HCQ). We investigated the effect of HCQ on the lipid profile of patients with Sjögren syndrome (SS).

METHODS

The present retrospective observational study included 71 female patients with SS treated with HCQ. The levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol, triglycerides (TG), and atherogenic index (TC/HDL) were measured at baseline, after 6 months, and 1, 3, and 5 years after initiation of HCQ treatment. Analysis to investigate changes over time was performed in the entire patient group and in the separate subgroups: those receiving (21 patients) and those not receiving (50 patients) hypolipidemic treatment.

RESULTS

For the entire group of patients a statistically significant decrease in TC was noted (levels before treatment 220 ± 41 mg/dl, and at 5 yrs 206 ± 32 mg/dl, p = 0.006). A statistically significant difference was observed in the levels of HDL (57 ± 14 mg/dl vs 67 ± 17 mg/dl, p < 0.001) and in atherogenic index (4.0 ± 1.3 vs 3.3 ± 0.9, p < 0.001). Patients not receiving a hypolipidemic agent during the same period demonstrated a decrease in TC (214 ± 40 mg/dl vs 208 ± 34 mg/dl, p = 0.049), an increase in HDL levels (55 ± 15 mg/dl vs 67 ± 18 mg/dl, p < 0.001), and a decrease in atherogenic index (4.0 ± 1.4 vs 3.3 ± 0.9, p < 0.001). In the subgroup of patients receiving hypolipidemic treatment, the respective changes in their lipid profile were not significant in the first years but became significant in the long term.

CONCLUSION

Use of HCQ in patients with SS was related to a statistically significant decrease in TC, an increase in HDL, and improvement in the atherogenic index.

Altered lipid levels in untreated patients with early polymyositis

Background

Little is known so far on the lipid profile in polymyositis (PM) patients. Our aim is to identify lipid profiles in untreated patients with early PM, to assess the association between lipid profiles and C-reactive protein (a sensitive marker of inflammation) in these patients.

Methods and Findings

This work was conducted as a case-control study. Sixty untreated patients with PM and 60 age- and sex-matched healthy controls were included. The duration of PM was less than six months, and none of them had received intermittent or regular corticosteroids or disease-modifying antirheumatic drugs or biological agents prior to the study. Triglyceride (TG), total cholesterol (TC), LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C), and C-reactive protein (CRP) were assessed using standard techniques. Thirty patients (50%) had a decreased level of HDL-C and 47% had an increased level of TG. The levels of HDL-C, LDL-C, and TC in PM were significantly lower than in controls (P<0.001, P<0.01, P<0.001, respectively). The level of TG was significantly higher in PM than in controls (P<0.001). The level of very low LDL-cholesterol (VLDL-C), and the ratios of VLDL-C/LDL-C, TC/HDL-C, and LDL-C/HDL-C were significantly higher than in controls (all P<0.001). Serum CRP levels correlated negatively with HDL-C (r = −0.352, P = 0.006) and TC (r = −0.262, P = 0.043). After adjustment for age, gender, smoking, drinking, body mass index, and pulmonary fibrosis/infection, linear regression model demonstrated that CRP is associated with HDL-C among PM patients (P = 0.028).

Conclusions

Dyslipidemia is a common feature in patients with PM that is characterized by a decrease in HDL-C and an increase in TG, suggesting a high risk of atherosclerosis. The Inflammatory condition in PM may account for the metabolism of HDL-C.

Assessment of blood clot formation and platelet receptor function ex vivo in patients with primary Sjogren's syndrome

OBJECTIVES

Primary Sjögren's syndrome (pSS) shares clinical features and pathogenetic mechanisms with systemic lupus erythematosus (SLE). SLE is associated with an increased thromboembolic risk; however, it is unclear whether pSS patients are susceptible to thromboembolic diseases. In this study, we examined ex vivo blood clot formation (clot strength, rates of clot formation and lysis) in pSS using thromboelastography (TEG) and platelet aggregation to common agonists using multiple electrode aggregometry (MEA). We also investigated the relationship between TEG/MEA parameters and clinical/laboratory features of pSS.

DESIGN

Case control.

SETTING

Secondary care, single centre.

PARTICIPANTS

34 pSS patients, 11 SLE patients and 13 healthy volunteers (all women) entered and completed the study.

PRIMARY OUTCOMES

TEG and MEA parameters between three subject groups.

SECONDARY OUTCOMES

The relationships between TEG/MEA and clinical/laboratory parameters analysed using bivariate correlation analysis with corrections for multiple testing.

RESULTS

All TEG and MEA parameters were similar for the three subject groups. After corrections for multiple testing, interleukin (IL)-1α and Macrophage inflammatory proteins (MIP)-1α remain correlated inversely with clot strength (r=-0.686, p=0.024 and r=-0.730, p=0.012, respectively) and overall coagulability (r=-0.640, p=0.048 and r=-0.648, p=0.048). Stepwise regression analysis revealed that several cytokines such as MIP-1α, IL-17a, IL-1α and Interferon (IFN)-γ may be key predictors of clot strength and overall coagulability in pSS.

CONCLUSIONS

Clot kinetics and platelet receptor function are normal in pSS. Several cytokines correlate with clot strength and overall coagulability in pSS.

Risk factors for coronary heart disease in connective tissue diseases

Atherosclerosis and cardiovascular disease risk is enhanced in certain connective tissue diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic vasculitis and antiphospholipid syndrome. The reason for this accelerated process is likely to be multifactorial. Traditional risk factors are more prevalent in some of these patient groups compared with the general population (e.g. smoking in RA and hypertension in SLE). However, these factors do not fully explain that enhanced risk. Chronic inflammation associated with these disorders as well as some specific autoantibodies have been shown to contribute to this increased risk although their role remains controversial. The role of therapies is unclear and while steroids may exacerbate metabolic risk factors, the anti-inflammatory effects of traditional and more novel biological therapies may reduce overall cardiovascular risk in these populations. We recommend proactive screening for modifiable cardiovascular risk factors in patients with these conditions.

The role of dyslipidemia on ocular surface, lacrimal and meibomian gland structure and function

PURPOSE

Dyslipidemia is characterized by high lipid blood levels that are risk factors for cardiovascular diseases, which are leading causes of death. However, it is unclear whether dyslipidemia is a cause of the dry eye syndrome (DES). Therefore we determined in transgenic mice models of dyslipidemia, whether there is an association with DES development.

METHODS

Dyslipidemic models included male and female adult mice overexpressing apolipoprotein CIII (Apo CIII), LDL receptor knockout (LDLR-KO) and ApoE knockout (ApoE-KO). They were compared with age- and gender-matched C57BL/6 mice. Ocular health was evaluated based on corneal slit lamp assessment, phenol red thread test (PRT) and impression cytology. Blood lipid profiles and histology of meibomian and lacrimal glands were also evaluated. Effects of high-fat diet and aging were observed in LDLR-KO and ApoCIII strains, respectively.

RESULTS

Body weight and lacrimal gland weight were significantly higher in male mice compared to females of the same strain (P < 0.05). Body weight was significantly lower in LDLRKO mice receiving high lipid diet compared to their controls (P = 0.0043). ApoE-KO were hypercholesterolemic and ApoCIII hypertriglyceridemic while LDLR-KO showed increases in both parameters. The PRT test was lower in male LDLR-KO mice with high-fat diet than control mice with standard diet (P = 0.0273). Aging did not affect lacrimal structural or functional parameters of ApoCIII strain.

CONCLUSIONS

DES development is not solely dependent on dyslipidemia in relevant mice models promoting this condition. On the other hand, lacrimal gland structure and function are differentially impacted by lipid profile changes in male and female mice. This dissociation suggests that other factors beside dyslipidemia impact on tear film dysfunction and DES development.

Text-mining applied to autoimmune disease research: the Sjögren's syndrome knowledge base

Background

Sjögren’s syndrome is a tissue-specific autoimmune disease that affects exocrine tissues, especially salivary glands and lacrimal glands. Despite a large body of evidence gathered over the past 60 years, significant gaps still exist in our understanding of Sjögren’s syndrome. The goal of this study was to develop a database that collects and organizes gene and protein expression data from the existing literature for comparative analysis with future gene expression and proteomic studies of Sjögren’s syndrome.

Description

To catalog the existing knowledge in the field, we used text mining to generate the Sjögren’s Syndrome Knowledge Base (SSKB) of published gene/protein data, which were extracted from PubMed using text mining of over 7,700 abstracts and listing approximately 500 potential genes/proteins. The raw data were manually evaluated to remove duplicates and false-positives and assign gene names. The data base was manually curated to 477 entries, including 377 potential functional genes, which were used for enrichment and pathway analysis using gene ontology and KEGG pathway analysis.

Conclusions

The Sjögren’s syndrome knowledge base ( http://sskb.umn.edu) can form the foundation for an informed search of existing knowledge in the field as new potential therapeutic targets are identified by conventional or high throughput experimental techniques.

Dyslipidaemia in rheumatological autoimmune diseases

Autoimmunity forms the basis of many rheumatological diseases, and may contribute not only to the classical clinical manifestations but also to the complications. Many of the autoimmune rheumatological diseases, including rheumatoid arthritis and systemic lupus erythematosus are associated with an excess cardiovascular morbidity and mortality. Much of this excess cardiovascular risk can be attributed to atherosclerotic disease. Atherosclerosis is a complex pathological process, with dyslipidaemia and inflammation fundamental to all stages of plaque evolution. The heightened inflammatory state seen in conjunction with many rheumatological diseases may accelerate plaque formation, both through direct effects on the arterial wall and indirectly through inflammation-mediated alterations in the lipid profile. Alongside these factors, antibodies produced as part of the autoimmune nature of these conditions may lead to alterations in the lipid profile and promote atherosclerosis. In this review, we discuss the association between several of the rheumatological autoimmune diseases and dyslipidaemia, and the potential cardiovascular impact this may confer.

Cardiovascular risk factors in primary Sjögren's syndrome: a case-control study in 624 patients

We evaluated the prevalence and clinical significance of cardiovascular risk factors in a large series of patients with primary Sjögren’s syndrome (SS), focusing on the possible association with clinical and immunological SS features, the therapies administered, and the impact on cardiovascular disease. The study cohort included 312 patients fulfilling the 2002 classification criteria for primary SS, consecutively evaluated and followed in our department between 1984 and 2009. The control group consisted of 312 age- and sex-matched patients without systemic autoimmune diseases followed during the study period in a primary care centre.

In comparison with the age- and sex-matched control group, patients with primary SS showed a higher frequency of diabetes mellitus (27% versus 13%, p < 0.001) and hypertriglyceridaemia (22% versus 15%, p = 0.023), and a lower frequency of hypertension (30% versus 46%, p < 0.001) and smoking (19% versus 31%, p < 0.001). The adjusted, multivariate analysis showed that SS patients with at least three cardiovascular risk factors had a higher mean age at SS diagnosis (p < 0.001), a higher frequency of liver involvement (p = 0.01) and central nervous system involvement (p = 0.001), higher mean levels of C-reactive protein (CRP, p = 0.001), a lower percentage of circulating gamma globulins (p = 0.001), and had received corticosteroids more frequently (p = 0.003) in comparison with patients without cardiovascular risk factors. Patients who had received corticosteroids showed a higher frequency of hypertension (37% versus 25%, p = 0.032), diabetes mellitus (37% versus 21%, p = 0.002), and hypertriglyceridaemia (33% versus 15%, p < 0.001).

Patients with primary SS showed a twofold higher prevalence of diabetes mellitus and a 1.5-fold higher prevalence of hypertriglyceridaemia in comparison with primary care patients. Corticosteroid use was closely associated with cardiovascular risk factors. These results suggest that cardiovascular risk factors should be taken into account in the management of patients with primary SS and show the importance of recognizing and controlling both traditional and SS-related modifiable risk factors.

Accelerated atherosclerosis in systemic lupus erythematosus and other connective tissue diseases

Connective tissue diseases are associated with increased morbidity and mortality related to a higher rate of cardiovascular events and higher prevalence of subclinical atherosclerosis. Atherosclerosis is now considered a multifactorial process where autoimmunity and chronic inflammation play an important pathogenic role. In systemic autoimmune rheumatic diseases in general, and in systemic lupus erythematosus in particular, atherosclerosis cannot be explained by traditional cardiovascular risk factors alone. Cellular and humoral mechanisms, together with specific factors associated with the disease itself and/or its treatments, have been advocated to explain the acceleration of arterial wall organic damage in these patients. Endothelial dysfunction, carotid intima-media thickness and plaque evaluations provide accurate detection of atherosclerotic process at a preclinical stage, before appearance of clinical disease, allowing preventive measure introduction with the aim to modify the cardiovascular risk in subjects with systemic autoimmune rheumatic diseases.

Is there a link between inflammation and abnormal lipoprotein profile in Sjögren's syndrome?

OBJECTIVES

To investigate the lipoprotein profile of patients with primary Sjögren's syndrome (pSS) and its association with laboratory tests, including markers of inflammation.

METHODS

This is a cross-sectional study among patients with pSS and healthy controls. We analyzed the lipoprotein profile of 73 pSS patients compared to 65 healthy individuals in the control group. We further evaluated possible associations between dyslipidemia in pSS patients and laboratory parameters including: hypergammaglobulinemia, autoantibodies [antinuclear antibodies (ANA), rheumatoid factor (RF), anti-Ro, anti-La], and acute-phase reactants [C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR)].

RESULTS

Patients and controls were comparable regarding the demographic variables. Lipoprotein profile was similar between pSS patients and controls: total cholesterol (204.0+/-43.39 versus 206.5+/-42.76 mg/mL, P=0.73), LDL fraction (131.6+/-37.38 versus 130.62+/-38.24 mg/dL, P=0.88) and HDL fraction (49.7+/-13.5 versus 51+/-11.5mg/dL, P=0.56), triglycerides (129.3+/-81.0 versus 116.8+/-53.5mg/dL, P=0.29). However, patients with pSS had a strong trend to present dyslipidemia when compared to healthy individuals (76.7% versus 61.5%, P=0.06). The presence of dyslipidemia in pSS was associated with increased ESR (44.05+/-28.07 versus 28.28+/-18.00, P=0.03), but not with other laboratory markers of the disease and inflammation.

DISCUSSION/CONCLUSION

pSS patients frequently present abnormal lipid profile, which are associated with higher levels of ESR. Thus, similar to other systemic inflammatory diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), lipid profile should be evaluated in pSS patients, with the aim of initiating specific therapeutic strategy for prevention of cardiovascular events.

Comorbidities in patients with primary Sjogren's syndrome: a registry-based case-control study

OBJECTIVE

Although multiple diseases associated with primary Sjögren's syndrome (pSS) have been reported, reliable data regarding the prevalence of specific medical comorbidities among patients with pSS remain sparse. We investigated the prevalence and risk for a broad spectrum of medical conditions among patients with pSS in Taiwan.

METHODS

A total of 1974 patients with pSS were eligible for inclusion in the study group. We randomly selected 9870 enrollees matched with the study subjects, using the Taiwan National Health Insurance Research Dataset for 2006 and 2007, inclusive. Conditional logistic regression analyses conditioned on sex, age, monthly income, and level of urbanization of the patient's community were used to calculate the odds ratios (OR) of various comorbid conditions.

RESULTS

Pearson chi-square tests revealed that patients with pSS had significantly higher prevalence of hyperlipidemia, cardiac arrhythmias, headaches, migraines, fibromyalgia (FM), asthma, pulmonary circulation disorders, hypothyroidism, liver disease, peptic ulcers, hepatitis B, deficiency anemias, depression, and psychoses. Conditional regression analyses showed that, compared to patients without the condition, patients with pSS were more likely to have hyperlipidemia (OR 1.42), cardiac arrhythmias (OR 1.32), headaches (OR 1.47), migraines (OR 1.86), FM (OR 1.71), asthma (OR 1.54), pulmonary circulation disorders (OR 1.42), hypothyroidism (OR 2.37), liver disease (OR 1.89), peptic ulcers (OR 1.88), hepatitis B (OR 2.34), deficiency anemias (OR 1.33), depression (OR 2.57), and psychoses (OR 2.15).

CONCLUSION

The prevalence of several comorbidities was increased among the patients with pSS. Our study provides epidemiological data for comorbidities among pSS patients in an ethnic Chinese population.

[Vasculopathy in Sjögren's syndrome]

Sjögren's syndrome is a systemic autoimmune disease with a predominant involvement of exocrine glands leading to sicca symptoms. Extraglandular involvement occurs in about 40% of patients with skin, musculoskeletal, neurological and organ manifestations. Systemic vasculitic manifestations of Sjögren's syndrome can be assumed in approximately 5%-10% of patients. Leukocytoclastic or cryoglobulinemic vasculitis represent classic vasculitic manifestations of Sjögren's syndrome. In the pathogenesis of vasculitis, B-cell-driven autoimmune processes play a major role by producing autoantibodies against the Ro/SS-A and La/SS-B antigens and cryoglobulins. In patients with Sjögren's syndrome, manifestation of vasculitis, non-Hodgkin's lymphoma and glomerulonephritis, as well as positive cryoglobulins and decreased levels of complement factors, are considered negative prognostic markers. Various immunosuppressive strategies, usually in co-medication with glucocorticoids, are used for the treatment of vasculitis in Sjögren's syndrome. For refractory and severe manifestations, a B-cell-targeted therapy with Rituximab should be also considered.

Altered expression of genes functioning in lipid homeostasis is associated with lipid deposition in NOD mouse lacrimal gland

Functional atrophy and accompanying lymphocytic infiltration and destruction of the lacrimal gland (LG) are characteristics of Sjögren's Syndrome (SjS). The male NOD mouse is an experimental model for the autoimmune exocrinopathy that develops in the LG of SjS patients. Acinar cells in LG of male NOD mice aged 3-4 months were previously shown to accumulate lipid droplets. In the current study, analysis of lipid components revealed that the accumulated lipids were mostly cholesteryl esters (CE). Gene expression microarray analysis followed by real-time RT-PCR revealed alterations in the expression of several genes involved in lipid homeostasis in LG of 12-week-old male NOD mice relative to matched BALB/c controls. A series of upregulated genes including apolipoprotein E, apolipoprotein F, hepatic lipase, phosphomevalonate kinase, ATP-binding cassette D1 and ATP-binding cassette G1 were identified. Comparison of liver mRNAs to LG mRNAs in BALB/c and NOD mice revealed that the differential expressions were LG-specific. Gene expression profiles were also characterized in LGs of female mice, younger mice and immune-incompetent NOD SCID mice. Investigation of the cellular distribution of Apo-E and Apo-F proteins suggested that these proteins normally coordinate to mediate lipid efflux from the acinar cells but that dysfunction of these processes due to missorting of Apo-F may contribute to CE deposition. Finally, the initiation and extent of lipid deposition were correlated with lymphocytic infiltration in the LG of male NOD mice. We propose that impaired lipid efflux contributes to lipid deposition, an event that may contribute to the development and/or progression of dacryoadenitis in the male NOD mouse.

Induction of scavenger receptor class B type I is critical for simvastatin enhancement of high-density lipoprotein-induced anti-inflammatory actions in endothelial cells

Changes in plasma lipoprotein profiles, especially low levels of high-density lipoprotein (HDL), are a common biomarker for several inflammatory and immune diseases, including atherosclerosis and rheumatoid arthritis. We examined the effect of simvastatin on HDL-induced anti-inflammatory actions. HDL and sphingosine 1-phosphate (S1P), a bioactive lipid component of the lipoprotein, inhibited TNF alpha-induced expression of VCAM-1, which was associated with NO synthase (NOS) activation, in human umbilical venous endothelial cells. The HDL- but not S1P-induced anti-inflammatory actions were enhanced by a prior treatment of the cells with simvastatin in a manner sensitive to mevalonic acid. Simvastatin stimulated the expression of scavenger receptor class B type I (SR-BI) and endothelial NOS. As for S1P receptors, however, the statin inhibited the expression of S1P(3) receptor mRNA but caused no detectable change in S1P(1) receptor expression. The reconstituted HDL, a stimulator of SR-BI, mimicked HDL actions in a simvastatin-sensitive manner. The HDL- and reconstituted HDL-induced actions were blocked by small interfering RNA specific to SR-BI regardless of simvastatin treatment. The statin-induced expression of SR-BI was attenuated by constitutively active RhoA and small interfering RNA specific to peroxisome proliferator-activated receptor-alpha. Administration of simvastatin in vivo stimulated endothelial SR-BI expression, which was accompanied by the inhibition of the ex vivo monocyte adhesion in aortas from TNF alpha-injected mice. In conclusion, simvastatin induces endothelial SR-BI expression through a RhoA- and peroxisome proliferator-activated receptor-alpha-dependent mechanism, thereby enhancing the HDL-induced activation of NOS and the inhibition of adhesion molecule expression.

Identification of possible candidate genes regulating Sjögren's syndrome-associated autoimmunity: a potential role for TNFSF4 in autoimmune exocrinopathy

Introduction

Sjögren syndrome (SjS) is a systemic autoimmune disease in which an immunological attack primarily against the salivary and lacrimal glands results in the loss of acinar cell tissue and function, leading to stomatitis sicca and keratoconjunctivitis sicca. In recent years, two genetic regions, one on chromosome 1 (designated autoimmune exocrinopathy 2 or Aec2) and the second on chromosome 3 (designated autoimmune exocrinopathy 1 or Aec1) derived from nonobese diabetic (NOD) mice, have been shown to be necessary and sufficient to replicate SjS-like disease in nonsusceptible C57BL/6 mice.

Methods

Starting with the SjS-susceptible C57BL/6-derived mouse, referred to as C57BL/6.NOD-Aec1Aec2, we generated a large set of recombinant inbred (RI) lines containing portions of Aec2 as a means of identifying more precisely the genetic elements of chromosome 1 responsible for disease development.

Results

Disease profiling of these RI lines has revealed that the SjS susceptibility genes of Aec2 lie within a region located at approximately 79 ± 5 cM distal to the centromere, as defined by microsatellite markers. This chromosomal region contains several sets of genes known to correlate with various immunopathological features of SjS as well as disease susceptibility genes for both type 1 diabetes and systemic lupus erythematosus in mice. One gene in particular, tumor necrosis factor (ligand) superfamily member 4 (or Ox40 ligand), encoding a product whose biological functions correlate with both physiological homeostasis and immune regulations, could be a potential candidate SjS susceptibility gene.

Conclusions

These new RI lines represent the first step not only in fine mapping SjS susceptibility loci but also in identifying potential candidate SjS susceptibility genes. Identification of possible candidate genes permits construction of models describing underlying molecular pathogenic mechanisms in this model of SjS and establishes a basis for construction of specific gene knockout mice.