Connective tissue disease-associated pulmonary hypertension: A comprehensive review

Economic burden of pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) in Finland

Objectives

Given that pulmonary arterial hypertension (PAH) and chronic thromboembolic hypertension (CTEPH) are rare yet severe subtypes of pulmonary hypertension significantly impacting patients' lives, this study analyzed the total societal costs of these conditions in Finland.

Methods

PAH (n = 247) and CTEPH (n = 177) patients diagnosed between 2008 and 2019 were analyzed for primary and specialty outpatient visits, emergency visits, hospitalizations, home and institutional care, sick leaves, disability pensions, and drug costs for 5 years before and after diagnosis.

Results

In PAH and CTEPH, annual specialty care number of outpatient visits increased from 3.8 and 3.3 (5 years before diagnosis) to 13.8 and 9.5 one-year post-diagnosis, then decreased to 9.2 and 4.0 at 5 years post-diagnosis. Annual inpatient days rose from 2.8 and 2.7 to 16.1 and 19.7 pre-diagnosis, then fell to 10.2 and 3.5 post-diagnosis, respectively. Within 5 years post-diagnosis, in working-age 70 % PAH and 42 % CTEPH patients received disability pensions. Drug therapy accounted for most costs (67 % in PAH and 60 % in CTEPH), followed by inpatient care, disability pensions, and outpatient care. Total costs were significantly lower for CTEPH, especially after pulmonary endarterectomy. Among PAH subtypes, the highest costs were in patients with PAH associated with connective tissue diseases.

Conclusions

PAH and CTEPH cause a significant economic burden on patients and society with considerable differences depending on the PAH subtype and whether the patient has undergone PEA operation or not.

Molecular Hydrogen Therapy in Sjögren's Syndrome With Pulmonary Arterial Hypertension and Right-sided Heart Failure: A Case Report of Improved Immune Markers Including Treg, B Cells and Plasma Cell

BACKGROUND/AIM

Connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH) is a severe complication characterized by elevated pulmonary artery pressure, which can lead to right heart failure and death, if untreated. Standard treatments often fail to adequately manage symptoms, highlighting the need for novel therapeutic approaches. This study investigated the efficacy of molecular hydrogen (H2) therapy in a patient with CTD-PAH.

CASE REPORT

We present the case of a 56-year-old female with CTD-PAH, diagnosed in 2013 with Sjogren's syndrome complicated by interstitial lung disease (ILD) and PAH. Despite treatment with sildenafil, bosentan, macitentan, iloprost, and corticosteroids, her condition deteriorated, resulting in severe dyspnea and cardiogenic shock in 2020. In May 2023, molecular hydrogen therapy was initiated as an adjuvant treatment. The patient received daily hydrogen capsules, which led to increased CD127+ Treg cells, reduced anti-Ro antibodies, and decreased B cell subsets. Her clinical symptoms stabilized without adverse effects.

CONCLUSION

This case highlights the potential benefits of molecular hydrogen therapy in CTD-PAH. H2 therapy exhibiting anti-inflammatory and immunomodulatory effects, leading to improved immune cell profiles and stabilizing clinical symptoms in a patient unresponsive to conventional treatments. Further research is needed to elucidate the mechanisms of H2 therapy and validate its efficacy in larger cohorts. Molecular hydrogen therapy shows promise as a safe adjunctive treatment for CTD-PAH, offering a new approach for managing this challenging condition.

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.

Exploring the Genetic Association Between Connective Tissue Diseases and the Risk of Pulmonary Arterial Hypertension: A Mendelian Randomization Analysis

This study aimed to explore the potential causal link between genetic predisposition to various connective tissue diseases (CTDs), namely systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), polymyositis (PM), dermatomyositis (DM), systemic sclerosis (SSc), mixed connective tissue disease (MCTD), and rheumatoid arthritis (RA), and the incidence of pulmonary arterial hypertension (PAH) utilizing Mendelian randomization (MR). Employing a two-sample MR approach, genetic variants associated with CTDs served as instrumental variables to investigate the exposure-outcome relationship, with GWAS data sourced from the FinnGen Biobank. Comprehensive statistical analyses, including the inverse variance weighted (IVW) method, were conducted, alongside heterogeneity, pleiotropy, and sensitivity tests to ensure the robustness and validity of findings. The results revealed that in the Finnish population, no significant causal associations were identified between PAH and SLE, SS, PM, DM, MCTD, or RA. Notably, a significant association was observed between SSc and an increased risk of PAH (IVW: OR = 1.278, 95% CI = 1.061-1.540, p = 0.010). However, this finding was not replicated in other European populations. These results indicate the unique genetic and pathological pathways underlying SSc-associated PAH, emphasizing the need for tailored screening and management protocols in this patient group.

The role of immune cells in the pathogenesis of connective tissue diseases-associated pulmonary arterial hypertension

Connective tissue diseases-related pulmonary arterial hypertension (CTD-PAH) is a disease characterized by an elevated pulmonary artery pressure that arises as a complication of connective tissue diseases. The number of patients with CTD-PAH accounts for 25.3% of all PAH patients. The main pathological features of CTD-PAH are thickening of intima, media and adventitia of pulmonary arterioles, increased pulmonary vascular resistance, autoimmune activation and inflammatory reaction. It is worth noting that abnormal immune activation will produce autoantibodies and release cytokines, and abnormal immune cell recruitment will promote inflammatory environment and vascular remodeling. Therefore, almost all forms of connective tissue diseases are related to PAH. In addition to general therapy and targeted drug therapy for PAH, high-dose glucocorticoid combined with immunosuppressant can quickly alleviate and stabilize the basic CTD-PAH disease. Given this, the development of therapeutic approaches targeting immune dysregulation and heightened inflammation is recognized as a promising strategy to prevent or reverse the progression of CTD-PAH. This review explores the potential mechanisms by which immune cells contribute to the development of CTD-PAH and examines the clinical application of immunosuppressive therapies in managing CTD-PAH.

Review of Pulmonary Manifestations in Antisynthetase Syndrome

Antisynthetase syndrome (ASyS) is now a widely recognized entity within the spectrum of idiopathic inflammatory myopathies. Initially described in patients with a triad of myositis, arthritis, and interstitial lung disease (ILD), its presentation can be diverse. Additional common symptoms experienced by patients with ASyS include Raynaud's phenomenon, mechanic's hand, and fever. Although there is a significant overlap with polymyositis and dermatomyositis, the key distinction lies in the presence of antisynthetase antibodies (ASAs). Up to 10 ASAs have been identified to correlate with a presentation of ASyS, each having manifestations that may slightly differ from others. Despite the proposal of three classification criteria to aid diagnosis, the heterogeneous nature of patient presentations poses challenges. ILD confers a significant burden in patients with ASyS, sometimes manifesting in isolation. Notably, ILD is also often the initial presentation of ASyS, requiring pulmonologists to remain vigilant for an accurate diagnosis. This article will comprehensively review the various aspects of ASyS, including disease presentation, diagnosis, management, and clinical course, with a primary focus on its pulmonary manifestations.

Connective tissue disease-associated pulmonary hypertension: A comprehensive review

Connective tissue diseases (CTDs) can be associated with various forms of pulmonary hypertension, including pulmonary arterial hypertension (PAH), pulmonary veno-occlusive disease, pulmonary venous hypertension, interstitial lung disease-associated pulmonary hypertension, chronic thromboembolic pulmonary hypertension, and sometimes a combination of several processes. The prevalence of PAH varies among the different CTDs, with systemic sclerosis (SSc) having the highest at 8%-12%. The most recent European Society of Cardiology/European Respiratory Society guidelines recommend routine annual screening for PAH in SSc and CTDs with SSc features. As CTDs can be associated with a myriad of presentations of pulmonary hypertension, a thorough evaluation to include a right heart catheterization to clearly delineate the hemodynamic profile is essential in developing an appropriate treatment plan. Treatment strategies will depend on the predominant phenotype of pulmonary vasculopathy. In general, management approach to CTD-PAH mirrors that of idiopathic PAH. Despite this, outcomes of CTD-PAH are inferior to those of idiopathic PAH, with those of SSc-PAH being particularly poor. Reasons for this may include extrapulmonary manifestations of CTDs, including renal disease and gastrointestinal involvement, concurrent interstitial lung disease, and differences in the innate response of the right ventricle to increased pulmonary vascular resistance. Early referral for lung transplant evaluation of patients with CTD-PAH, particularly SSc-PAH, is recommended. It is hoped that in the near future, additional therapies may be added to the armamentarium of effective treatments for CTD-PAH. Ultimately, a better understanding of the pathogenesis of CTD-PAH will be required to develop targeted therapies for this morbid condition.