Prevalence of primary Sjögren's syndrome in patients undergoing evaluation for pulmonary arterial hypertension

Sex Dimorphism in Pulmonary Arterial Hypertension Associated With Autoimmune Diseases

Pulmonary hypertension is a rare, incurable, and progressive disease. Although there is increasing evidence that immune disorders, particularly those associated with connective tissue diseases, are a strong predisposing factor in the development of pulmonary arterial hypertension (PAH), there is currently a lack of knowledge about the detailed molecular mechanisms responsible for this phenomenon. Exploring this topic is crucial because patients with an immune disorder combined with PAH have a worse prognosis and higher mortality compared with patients with other PAH subtypes. Moreover, data recorded worldwide show that the prevalence of PAH in women is 2× to even 4× higher than in men, and the ratio of PAH associated with autoimmune diseases is even higher (9:1). Sexual dimorphism in the pathogenesis of cardiovascular disease was explained for many years by the action of female sex hormones. However, there are increasing reports of interactions between sex hormones and sex chromosomes, and differences in the pathogenesis of cardiovascular disease may be controlled not only by sex hormones but also by sex chromosome pathways that are not dependent on the gonads. This review discusses the role of estrogen and genetic factors including the role of genes located on the X chromosome, as well as the potential protective role of the Y chromosome in sexual dimorphism, which is prominent in the occurrence of PAH associated with autoimmune diseases. Moreover, an overview of animal models that could potentially play a role in further investigating the aforementioned link was also reviewed.

Pulmonary hypertension in connective tissue diseases: epidemiology, pathogenesis, and treatment

Pulmonary hypertension (PH) is a clinical condition characterized by increased pulmonary arterial pressure arising from a heterogeneous range of diseases that has a deteriorating effect on the quality of life and may cause early mortality if left untreated. Connective tissue disorders (CTD)-associated PH is the second most common cause of pulmonary arterial hypertension (PAH), after the idiopathic form, categorized as group I. Systemic scleroderma (SSc) accounts for 75% of CTD-associated PH cases. Although SSc ranks first place for CTD-associated PH, SSc is followed by systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD), having a lesser frequency of PH occurrence, while it occurs as a rare complication in cases with rheumatoid arthritis (RA) and inflammatory myositis. PH may also occur during non-SSc CTDs and even other rheumatic diseases, including Behcet's disease and adult-onset Still's disease, albeit to a lesser extent. The prognosis of CTD-associated PH is worse than the other forms of PH. Although, as in idiopathic pulmonary arterial hypertension (IPAH), the mechanism of CTD-related PH is associated with an increase in vasoconstrictors like endothelin-1 and a decrease in vasodilators like prostacyclin and nitric oxide production, inflammation, and autoimmune mechanisms also play a role in the development and progression of PH. This may lead to the involvement of more than one mechanism in CTD-associated PH. Knowing which mechanism is dominant is very important in determining the treatment option. This review will primarily focus on the epidemiology, risk factors, and prognosis of PH that develops during rheumatic diseases; the pathogenesis and treatment will be briefly mentioned in light of the newly published guidelines. Key Points • Pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD) in Western countries is the second most common type of PAH after idiopathic PAH (IPAH). • CTD-PH can be seen most often in systemic scleroderma (SSc), less in systemic lupus erythematosus (SLE), mixed CTD (MCTD), and rarely in other CTDs. • While current guidelines recommend annual transthoracic echocardiography as a screening test for asymptomatic SSc patients, screening for PH is not advised in the absence of symptoms suggestive of PH in other CTDs. • CTD-PH treatment can be divided into specific vasodilator PH treatments and immunosuppressive therapy. Current treatment guidelines recommend the same treatment algorithm for patients with CTD-associated PH as for patients with IPAH. Several case series have shown the beneficial effect of immunosuppressive agents in patients with SLE-PH and MCTD-PH.

Clinical characteristics and risk factors for primary Sjögrens syndrome complicated with pulmonary arterial hypertension

OBJECTIVES

Primary Sjögren's syndrome (pSS) is involved in pulmonary tissue. Pulmonary arterial hypertension (PAH) is one of the pulmonary complications caused by pSS. This study aims to investigate the clinical characteristics and risk factors for pSS complicated with PAH.

METHODS

We retrospectively analyzed 165 patients in the Second Xiangya Hospital of Central South University. They were divided into a pSS-PAH group (n=86) and a pSS group (n=79) according to pulmonary artery pressure detected by color doppler echocardiography. The clinical characteristics, laboratory test indexes, and risk factors were compared between the 2 groups.

RESULTS

Among 165 patients with pSS, 86 patients (52.12%) had PAH. Females were 79 (91.90%) patients in the pSS-PAH group, more than males. The patients in the pSS-PAH group were older than those in the pSS group (all P<0.05). The incidence of keratoconjunctivitis, alopecia, Raynaud's phenomenon, cough, chest tightness, shortness of breath, and dry skin was higher (all P<0.05), and the incidence of pulmonary infection, pulmonary cystic degeneration, respiratory failure, osteoporosis, arteriosclerosis, and hypertension were higher in the pSS-PAH group than those in the pSS group (all P<0.05). The laboratory indicators of pulmonary artery diameter, right atrium diameter, right ventricular contractile diameter and pulmonary artery systolic pressure were higher in the pSS-PAH group than those in the pSS group (all P<0.05), and the positive rates of anti-nuclear antibody, anti-SSA antibody, and anti-Ro-52 antibody were higher (all P<0.05). The incidence of restrictive ventilatory dysfunction and decreased lung diffusion volume in the pSS-PAH group was higher than that in the pSS group (both P<0.05). Advanced age (OR=1.094, 95% CI 1.053 to 1.137, P<0.001), concomitant keratoconjunctivitis (OR=2.075, 95% CI 1.054 to 4.088, P=0.035), hair loss (OR=2.655, 95% CI 1.368 to 5.152, P=0.004), dry skin (OR=2.696, 95% CI 1.364 to 5.332, P=0.004), high pulmonary artery systolic pressure (OR=1.185, 95% CI 1.125 to 1.248, P<0.001), respiratory failure (OR=2.279, 95% CI 1.137 to 4.570, P=0.020), osteoporosis (OR=2.087, 95% CI 1.025 to 4.248, P=0.043), atherosclerosis (OR=2.251, 95% CI 1.146 to 4.423, P=0.018), hypertension (OR=2.370, 95% CI 1.190 to 4.718, P=0.014), the increased antinuclear antibody (OR=2.155, 95% CI 1.094 to 4.245, P=0.026), the increased anti-SSA antibody (OR=2.565, 95% CI 1.292 to 5.091, P=0.007), the increased anti-RO-52 antibody (OR=2.623, 95% CI 1.278 to 5.383, P=0.009), and the decreased lung dispersion (OR=2.602, 95% CI 1.386 to 4.884, P=0.003), were all risk factors for PAH in pSS patients.

CONCLUSIONS

The incidence of pSS-PAH is high in this study. The advanced age, elevated pulmonary artery systolic pressure, concomitant keratoconjunctivitis, alopecia, dry skin, respiratory failure, osteoporosis, arteriosclerosis, and hypertension, increased anti-nuclear antibody, anti-SSA antibody, and anti-Ro-52 antibody, and decreased pulmonary dispersion suggest that the risk of PAH is significantly increased in patients with pSS.

Therapeutic Strategy for Patients with Concomitant Pulmonary Artery Hypertension and Hypertrophic Obstructive Cardiomyopathy: A Rare Case Report

Combined cases of hypertrophic obstructive cardiomyopathy (HOCM) and pulmonary arterial hypertension (PAH) are rare and have a management dilemma. Although preload is crucial in the management of HOCM, anti-PAH agents dramatically change the preload, leading to improving or worsening heart failure in patients with HOCM. We had a 74-year-old woman with Sjogren-syndrome-associated PAH. Her heart failure worsened following the initiation of anti-PAH agents due to an incremental preload on the left ventricle, whereas HOCM clinically developed following the termination of anti-PAH agents and progressing anorexia due to the progression of the left ventricular outflow obstruction. Careful monitoring of the left ventricular outflow obstruction during initiation/termination of anti-PAH agents and medical intervention to the HOCM are highly recommended.

Cardiovascular Disease in Primary Sjögren's Syndrome: Raising Clinicians' Awareness

In the ever evolving landscape of systemic immune mediated diseases, an increased awareness regarding the associated cardiovascular system impairment has been noted in recent years. Even though primary Sjögren's Syndrome (pSS) is one of the most frequent autoimmune diseases affecting middle-aged individuals, the cardiovascular profile of this specific population is far less studied, at least compared to other autoimmune diseases. Traditional cardiovascular risk factors and disease specific risk factors are inextricably intertwined in this particular case. Therefore, the cardiovascular risk profile in pSS is a multifaceted issue, sometimes difficult to assess. Furthermore, in the era of multimodality imaging, the diagnosis of subclinical myocardial and vascular damage is possible, with recent data pointing that the prevalence of such involvement is higher in pSS than in the general population. Nevertheless, when approaching patients with pSS in terms of cardiovascular diseases, clinicians are often faced with the difficult task of translating data from the literature into their everyday practice. The present review aims to synthesize the existing evidence on pSS associated cardiovascular changes in a clinically relevant manner.

The Role of Regulatory T Cells in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a chronic, incurable condition characterized by pulmonary vascular remodeling, perivascular inflammation, and right heart failure. Regulatory T cells (Tregs) stave off autoimmunity, and there is increasing evidence for their compromised activity in the inflammatory milieu of PAH. Abnormal Treg function is strongly correlated with a predisposition to PAH in animals and patients. Athymic Treg-depleted rats treated with SU5416, an agent causing pulmonary vascular injury, develop PAH, which is prevented by infusing missing CD4⁺CD25^highFOXP3⁺ Tregs. Abnormal Treg activity may also explain why PAH disproportionately affects women more than men. This mini review focuses on the role of Tregs in PAH with a special view to sexual dimorphism and the future promise of Treg therapy.

Endostatin and Vascular Endothelial Growth Factor-A165b May Contribute to Classification of Pulmonary Hypertension

Background: Pulmonary hypertension (PH) is characterized by dysregulation of small pulmonary arteries. In addition to endostatin (ES), placenta growth factor (PlGF), vascular endothelial growth factor-A (VEGF-A), and the anti-angiogenesis isoform of VEGF-A (VEGF-A₁₆₅b) are associated with PH. However, the usefulness of these biomarkers in PH in unknown. We investigated whether these 4 biomarkers are related to PH classification. Methods and Results: Between July 2015 and August 2017, 33 control patients and 107 PH patients were enrolled in the study. Among the PH patients, 48 had pulmonary arterial hypertension (PAH), 5 had left heart disease-associated PH (LHD-PH), 4 had lung disease-associated PH (LD-PH), and 50 had chronic thromboembolic PH (CTEPH). Among the PAH patients, 16 had idiopathic PAH (IPAH) and 17 had connective tissue disease-associated PAH (CTD-PAH). PlGF, total VEGF-A, and VEGF-A₁₆₅b levels were measured in the control and PH groups. ES was only measured in the PH group. VEGF-A₁₆₅b levels were significantly higher in the LD-PH group than in the PAH, LHD-PH, and CTEPH groups (all P<0.001). PlGF levels were significantly higher in the CTD-PAH group than in the IPAH and control groups. ES levels were significantly correlated with the 6-min walk distance (P<0.001), B-type natriuretic peptide (P<0.001), and pulmonary vascular resistance (P=0.008). Conclusions: ES could detect CTD-PAH in PAH and may be an indicator of PH severity. VEGF-A₁₆₅b was useful in detecting LD-PH.

A case of pulmonary arterial hypertension complicated by anti-neutrophil cytoplasmic antibody-associated vasculitis and systemic sclerosis

Pulmonary arterial hypertension (PAH) is a rare complication of ANCA-associated vasculitis (AAV). We report a 37-year-old man with PAH complicated by both AAV and SSc who presented with dyspnea, cardiac enlargement, positive myeloperoxidase (MPO)-ANCA, anti-centromere antibodies, proteinuria, and urinary casts. Elevated pulmonary arterial pressure (58/22/34 mmHg) and low PAWP (2 mmHg) were confirmed by right heart catheterization. Treatment with glucocorticoids (GC) decreased urinary protein and serum MPO-ANCA; however, PAH did not respond to GC. Therefore, a combination of beraprost, bosentan, and tadalafil was needed. The differences in responses to GC suggest that the pathophysiology of nephropathy is different from that of PAH. We considered that nephropathy was associated with AAV but that PAH was associated with SSc in the present case. We discuss the pathophysiology and treatment response of PAH complicated by AAV, referring to nine past cases.

Sjogren's Syndrome and Pulmonary Disease

Sjogren's syndrome is an autoimmune connective tissue disease targeting the exocrine glands and frequently affecting the respiratory system. The pulmonary disease is the most important extra-glandular manifestation as it carries most of the morbidity and mortality. Typically, it affects the small airways ranging from mild to severe respiratory symptoms. The upper airways are also commonly involved, predisposing sinusitis to occur more frequently than in the normal population. Lymphocytic interstitial pneumonia was initially thought to be the prevailing parenchymal disease; however, multiple cohorts report non-interstitial pneumonia to be the most frequent subtype of interstitial lung disease. In the review of high-resolution computed tomography scans, cystic lesions are commonly found and associate with both the small airways and parenchymal disease. Under their presence, amyloidosis or lymphomas should be considered in the differential. Overall, Sjogren's syndrome has a higher risk for lymphoma, and in lungs this condition should be thought of, especially when the images reveal pulmonary nodularity, lymphocytic interstitial pneumonia and lymphadenopathy. Although, pulmonary artery hypertension was traditionally and exceptionally linked with Sjogren's syndrome, together with systemic lupus erythematosus, they are now acknowledged to be the most common pulmonary vascular disease in east Asian populations, even over patients with systemic sclerosis. Although there are no controlled prospective trials to treat pulmonary disease in Sjogren's syndrome, the mainstay treatment modality still falls on glucocorticoid therapy (systemic and inhaled), combined with immune modulators or alone. Most of the evidence sustains successful outcomes based on reported cases or case series.

Primary Sjögren's Syndrome and Cardiovascular Disease

Sjögren's syndrome is a rheumatic autoimmune disease that primarily affects middle-aged women and runs a slowly progressing course with sicca symptoms being the prevalent manifestation. Premature atherosclerosis and increased cardiovascular (CV) morbidity and mortality are frequently encountered in rheumatic diseases characterized by significant systemic inflammation, such as the inflammatory arthritides, systemic vasculitides and systemic lupus erythematosus. In the same context, chronic inflammation and immune aberrations underlying Sjögren's syndrome are also reported to be associated with augmented risk of atherosclerosis. Increased CV disease (CVD) frequency has been found in recent meta-analyses. The involvement of the CV system is not a common feature of Sjögren's syndrome; however, specific manifestations, such as autoantibody-mediated heart block, pericarditis, pulmonary arterial hypertension and dysautonomia, have been described. This review focuses on studies addressing CV morbidity in Sjögren's syndrome and presents current data regarding distinct CV features of the disease.

Autoantibody clustering of lupus-associated pulmonary hypertension

Objective

To define the SLE phenotype associated with pulmonary hypertension using multiple autoantibodies.

Methods

207 (8%) patients with SLE with pulmonary hypertension, defined as a right ventricular systolic pressure greater than 40 mm Hg on transthoracic echocardiogram or as pulmonary artery dilatation on CT of the chest, were identified from the Hopkins Lupus Cohort (94.2% female; 56.5% African–American, 39% Caucasian; mean age 45.6 years). 53 patients were excluded from the clustering analysis due to incomplete autoantibody profiles. Agglomerative hierarchical clustering algorithm with Ward’s method was used to cluster the patients with pulmonary hypertension, based on their autoantibodies. Autoantibodies used in the clustering analysis included lupus anticoagulant, anticardiolipin, anti-beta 2 glycoprotein I, antidouble-stranded DNA, anti-Sm (anti-Smith), antiribonucleoprotein, false positive-rapid plasma reagin, anti-Ro, anti-La and hypocomplementaemia (C3 ever low or C4 ever low). The Dunn index was used to internally validate the clusters. Bootstrap resampling derived the mean Jaccard coefficient for each cluster. All analyses were performed in R V.3.6.1 using the packages cluster, fpc and gplots.

Results

A significantly higher prevalence of pulmonary hypertension in African–American patients with SLE, compared with Caucasian patients with SLE (11.5% vs 5.9%, p<0.0001), was found. Based on equivalent Dunn indices, the 154 patients with SLE-associated pulmonary hypertension with complete autoantibody data were divided into five clusters, three of which had mean Jaccard coefficients greater than 0.6. Hypocomplementaemia, renal disorder and age at diagnosis significantly differed across clusters. One cluster was defined by antiphospholipid antibodies. One cluster was defined by anti-Ro and anti-La. One cluster had low frequencies of all antibodies.

Conclusion

SLE-associated pulmonary hypertension disproportionately affects African–American patients. Pulmonary hypertension in SLE is defined by five autoantibody clusters. Antiphospholipid antibodies, anti-Ro and anti-La positivity, serological activity, and age at pulmonary hypertension diagnosis significantly differed across clusters, possibly indicating different pathophysiological mechanisms.