Pulmonary arterial hypertension in the setting of scleroderma is different than in the setting of lupus: A review

Immunotherapy for Pulmonary Arterial Hypertension: From the Pathogenesis to Clinical Management

Pulmonary hypertension (PH) is a progressive cardiovascular disease, which may lead to severe cardiopulmonary dysfunction. As one of the main PH disease groups, pulmonary artery hypertension (PAH) is characterized by pulmonary vascular remodeling and right ventricular dysfunction. Increased pulmonary artery resistance consequently causes right heart failure, which is the major reason for morbidity and mortality in this disease. Although various treatment strategies have been available, the poor clinical prognosis of patients with PAH reminds us that further studies of the pathological mechanism of PAH are still needed. Inflammation has been elucidated as relevant to the initiation and progression of PAH, and plays a crucial and functional role in vascular remodeling. Many immune cells and cytokines have been demonstrated to be involved in the pulmonary vascular lesions in PAH patients, with the activation of downstream signaling pathways related to inflammation. Consistently, this influence has been found to correlate with the progression and clinical outcome of PAH, indicating that immunity and inflammation may have significant potential in PAH therapy. Therefore, we reviewed the pathogenesis of inflammation and immunity in PAH development, focusing on the potential targets and clinical application of anti-inflammatory and immunosuppressive therapy.

Pulmonary Hypertension in Connective Tissue Diseases Other than Systemic Sclerosis

Pulmonary hypertension (PH) is a known complication of certain connective tissue diseases (CTDs), with systemic sclerosis (SSc) being the most common in the Western world. However, PH in association with non-SSc CTD such as systemic lupus erythematous, mixed connective tissue disease, and primary Sjögren's syndrome constitutes a distinct subset of patients with inherently different epidemiologic profiles, pathophysiologic mechanisms, clinical features, therapeutic options, and prognostic implications. The purpose of this review is to inform a practical approach for clinicians evaluating patients with non-SSc CTD-associated PH.The development of PH in these patients involves a complex interplay between genetic factors, immune-mediated mechanisms, and endothelial cell dysfunction. Furthermore, the broad spectrum of CTD manifestations can contribute to the development of PH through various pathophysiologic mechanisms, including intrinsic pulmonary arteriolar vasculopathy (pulmonary arterial hypertension, Group 1 PH), left-heart disease (Group 2), chronic lung disease (Group 3), chronic pulmonary artery obstruction (Group 4), and unclear and/or multifactorial mechanisms (Group 5). The importance of diagnosing PH early in symptomatic patients with non-SSc CTD is highlighted, with a review of the relevant biomarkers, imaging, and diagnostic procedures required to establish a diagnosis.Therapeutic strategies for non-SSc PH associated with CTD are explored with an in-depth review of the medical, interventional, and surgical options available to these patients, emphasizing the CTD-specific considerations that guide treatment and aid in prognosis. By identifying gaps in the current literature, we offer insights into future research priorities that may prove valuable for patients with PH associated with non-SSc CTD.

A prognostic model for systemic lupus erythematosus-associated pulmonary arterial hypertension: CSTAR-PAH cohort study

BACKGROUND

Pulmonary arterial hypertension is a major cause of death in systemic lupus erythematosus, but there are no tools specialized for predicting survival in systemic lupus erythematosus-associated pulmonary arterial hypertension.

RESEARCH QUESTION

To develop a practical model for predicting long-term prognosis in patients with systemic lupus erythematosus-associated pulmonary arterial hypertension.

METHODS

A prognostic model was developed from a multicenter, longitudinal national cohort of consecutively evaluated patients with systemic lupus erythematosus-associated pulmonary arterial hypertension. The study was conducted between November 2006 and February 2020. All-cause death was defined as the endpoint. Cox regression and least absolute shrinkage and selection operators were used to fit the model. Internal validation of the model was assessed by discrimination and calibration using bootstrapping.

RESULTS

Of 310 patients included in the study, 81 (26.1%) died within a median follow-up of 5.94 years (interquartile range 4.67-7.46). The final prognostic model included eight variables: modified World Health Organization functional class, 6-min walking distance, pulmonary vascular resistance, estimated glomerular filtration rate, thrombocytopenia, mild interstitial lung disease, N-terminal pro-brain natriuretic peptide/brain natriuretic peptide level, and direct bilirubin level. A 5-year death probability predictive algorithm was established and validated using the C-index (0.77) and a satisfactory calibration curve. Risk stratification was performed based on the predicted probability to improve clinical decision-making.

CONCLUSIONS

This new risk stratification model for systemic lupus erythematosus-associated pulmonary arterial hypertension may provide individualized prognostic probability using readily obtained clinical risk factors. External validation is required to demonstrate the accuracy of this model's predictions in diverse patient populations.

The PH-ILD Detection tool: External validation and use in patients with ILD

Pulmonary hypertension (PH) results in increased morbidity and mortality in patients with interstitial lung disease (ILD). Early recognition of PH in this population is essential for planning diagnostic testing, initiating therapy, and evaluating for lung transplantation. The previously developed PH-ILD Detection tool has significant potential in the evaluation and treatment of ILD patients; the aim of this study was to validate the tool in an independent, multicenter cohort of patients. We conducted a retrospective review of prospectively collected data from 161 ILD patients. Patients were stratified into low- (n = 78, 48.4%), intermediate- (n = 54, 33.5%), and high-risk (n = 29, 18.0%) groups based on the score obtained with the tool. Intermediate- and high-risk patients underwent follow-up echocardiogram (TTE); 49.4% (n = 41) had an abnormal TTE suggestive of underlying PH. These patients underwent right heart catheterization; PH-ILD was diagnosed in 73.2% (n = 30) of these cases. The PH-ILD Detection tool has a sensitivity of 93.3%, specificity of 90.9%, and area-under-the-curve of 0.921 for diagnosing PH in ILD patients, validating the findings from the original study and establishing the tool as a fundamental resource for early recognition of PH in ILD patients.

Immunosuppression for the treatment of pulmonary hypertension in patients with systemic lupus erythematosus: A systematic review

PURPOSE

To conduct a systematic review with meta-analysis to determine the effects of immunosuppression on Group 1 Pulmonary Arterial Hypertension in patients with systemic lupus erythematosus (SLE).

METHODS

We searched Medline, Embase, Web of Science, Clinicaltrials.gov, and Cochrane Central Register of Controlled Trials (CENTRAL) with a search strategy developed by a medical librarian. We included retrospective, cross-sectional, case-control, prospective studies, and randomized controlled trials (RCTs) in our analysis and only included studies that contained data for patients with SLE. We included any immunosuppressive agents (including but not limited to cyclophosphamide, glucocorticoids, mycophenolate mofetil, azathioprine, and rituximab) We assessed for risk of bias and certainty of evidence. Outcomes included hemodynamics (as measured by pulmonary arterial hypertension), functional status, 6 minute walk test (6MWT), quality of life, mortality, and serious adverse events.

RESULTS

We included three studies. One RCT and two single-arm interventional observational studies. The RCT had a high risk of bias whereas the two single-arm interventional studies were graded as fair quality. Meta-analysis could not be conducted because of insufficient data. The RCT showed significant improvements in hemodynamics (as measured by pulmonary arterial pressures) and functional status. One observational study showed improvements in hemodynamics, functional status, and 6MWT. There were insufficient data for serious adverse events, mortality, and quality of life.

CONCLUSIONS

Despite a high prevalence and with a poor prognosis, there is a paucity of data for the role of immunosuppression in the treatment of Group 1 Pulmonary Arterial Hypertension in SLE. More high-quality studies are needed, especially to investigate serious adverse events and quality of life.

Serum Biomarkers in Connective Tissue Disease-Associated Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening complication of connective tissue diseases (CTDs) characterised by increased pulmonary arterial pressure and pulmonary vascular resistance. CTD-PAH is the result of a complex interplay among endothelial dysfunction and vascular remodelling, autoimmunity and inflammatory changes, ultimately leading to right heart dysfunction and failure. Due to the non-specific nature of the early symptoms and the lack of consensus on screening strategies-except for systemic sclerosis, with a yearly transthoracic echocardiography as recommended-CTD-PAH is often diagnosed at an advanced stage, when the pulmonary vessels are irreversibly damaged. According to the current guidelines, right heart catheterisation is the gold standard for the diagnosis of PAH; however, this technique is invasive, and may not be available in non-referral centres. Hence, there is a need for non-invasive tools to improve the early diagnosis and disease monitoring of CTD-PAH. Novel serum biomarkers may be an effective solution to this issue, as their detection is non-invasive, has a low cost and is reproducible. Our review aims to describe some of the most promising circulating biomarkers of CTD-PAH, classified according to their role in the pathophysiology of the disease.

Pulmonary hypertension in patients with interstitial lung disease: a tool for early detection

Pulmonary hypertension (PH) complicates the treatment of interstitial lung disease (ILD) patients resulting in poor functional status and worse outcomes. Early recognition of PH in ILD is important for initiating therapy and considering lung transplantation. However, no standard exists regarding which patients to screen for PH-ILD or the optimal method to do so. The aim of this study was to create a risk assessment tool that could reliably predict PH in ILD patients. We developed a PH-ILD Detection tool that incorporated history, exam, 6-min walk distance, diffusion capacity for carbon monoxide, chest imaging, and cardiac biomarkers to create an eight-component score. This tool was analyzed retrospectively in 154 ILD patients where each patient was given a score ranging from 0 to 12. The sensitivity (SN) and specificity (SP) of the PH-ILD Detection tool and an area-under-the-curve (AUC) were calculated. In this cohort, 74 patients (48.1%) had PH-ILD. A score of ≥6 on the PH-ILD Detection tool was associated with a diagnosis of PH-ILD (SN: 86.5%; SP: 86.3%; area-under-the-curve: 0.920, p < 0.001). The PH-ILD Detection tool provides high SN and SP for detecting PH in ILD patients. With confirmation in larger cohorts, this tool could improve the diagnosis of PH in ILD and may suggest further testing with right heart catheterization and earlier intervention with inhaled treprostinil and/or lung transplant evaluation.

Predicting the Risk of Pulmonary Arterial Hypertension in Systemic Lupus Erythematosus: A Chinese Systemic Lupus Erythematosus Treatment and Research Group Cohort Study

OBJECTIVE

Pulmonary arterial hypertension (PAH) is a life-threatening complication of systemic lupus erythematosus (SLE). However, there is no algorithm to identify those at high risk. This study was undertaken to develop a prediction model for PAH in patients with lupus that provides individualized risk estimates.

METHODS

A multicenter, longitudinal cohort study was undertaken from January 2003 to January 2020. The study collected data on 3,624 consecutively evaluated patients diagnosed as having SLE. The diagnosis of PAH was confirmed by right-sided heart catheterization. Cox proportional hazards regression and least absolute shrinkage and selection operator were used to fit the model. Model discrimination, calibration, and decision curve analysis were performed for validation.

RESULTS

Ninety-two lupus patients (2.54%) developed PAH during a median follow-up of 4.84 years (interquartile range 2.42-8.84). The final prediction model included 5 clinical variables (acute/subacute cutaneous lupus, arthritis, renal disorder, thrombocytopenia, and interstitial lung disease) and 3 autoantibodies (anti-RNP, anti-Ro/SSA and anti-La/SSB). A 10-year PAH probability-predictive nomogram was established. The model was internally validated by Harrell's concordance index (0.78), the Brier score (0.03), and a satisfactory calibration curve. According to the net benefit and predicted probability thresholds, we recommend annual screening in high-risk (>4.62%) lupus patients.

CONCLUSION

We developed a risk stratification model using routine clinical assessments. This new tool may effectively predict the future risk of PAH in patients with SLE.

Scleroderma-associated thrombotic microangiopathy in overlap syndrome of systemic sclerosis and systemic lupus erythematosus: A case report and literature review

RATIONALE

Systemic sclerosis (SSc) is a serious multisystem connective tissue disease. When SSc is accompanied by systemic lupus erythematosus (SLE), called SSc-SLE overlap syndrome. SSc associated thrombotic microangiopathy (SSc-TMA) can lead to scleroderma renal crisis, it mainly manifests hypertension or even malignant hypertension, acute kidney injury, and higher mortality. The case of SSc-SLE overlap syndrome combined with SSc-TMA has rarely been reported.

PATIENT CONCERNS

We report the case of an elderly male with SSc-SLE overlap syndrome combined with scleroderma renal crisis and SSc-TMA.

DIAGNOSES

The patient has typical of SSc on the face and hands, combined with pulmonary artery hypertension, interstitial lung disease, heart failure and malignant hypertension, as well as SLE, lupus nephritis class V, and TMA, which were definitively diagnosed by clinical laboratory examination and renal histopathology.

INTERVENTIONS

The patient was treated with prednisone, cyclophosphamid, renin-angiotensin system inhibitors, diuretics, and acetylcysteine.

OUTCOMES

The patient died suddenly of heart failure on the 35th day after discharge.

LESSONS

The occurrence of TMA leads to the deterioration of the prognosis of SSC-SLE overlap syndrome. The diagnosis of SSC-TMA in SSc-SLE overlap syndrome depends on clinical laboratory examination and renal histopathology.

Pulmonary manifestations of systemic lupus erythematosus and Sjögren's syndrome

PURPOSE OF REVIEW

Systemic lupus erythematosus (SLE) and Sjögren syndrome are chronic autoimmune inflammatory disorders that can present with multiorgan involvement including the lungs. This review will focus on recent literature pertaining to the epidemiology, pathogenesis, clinical presentation and diagnosis and management of SLE and Sjögren syndrome-associated pulmonary conditions.

RECENT FINDINGS

Pulmonary manifestations of both disease entities have been well characterized and lung involvement can be observed during the course of the disease in most cases. Pulmonary manifestations of SLE and Sjögren syndrome can be classified based on anatomical site of involvement; and the large and small airways, lung parenchyma, lung vasculature, pleura and respiratory muscles can be involved. The pleura is most commonly involved in SLE, whereas the airways are most commonly involved in primary Sjögren's syndrome (pSS). Sleep disturbances have also been described in both entities.

SUMMARY

Although further research into treatment strategies for the pulmonary complications seen in SLE and pSS is needed, the clinician should be aware of the risk factors and clinical presentation of the various pulmonary complications in SLE and pSS in order to identify patients who should be screened and/or have modifications in treatment strategies to mitigate the morbidity and mortality associated with these complications.

Hypercoagulability in Pulmonary Hypertension

Pulmonary hypertension (PH) is divided into varied pathophysiological and etiologic groupings, as classified by the World Health Organization (WHO). Pulmonary arterial hypertension (PAH), which falls under WHO group 1 PH, is a progressive and potentially fatal disease characterized by a vasoconstrictive, proliferative, and thrombotic phenotype, which leads to increased pulmonary artery pressure, right heart failure, and death. Pathologically, in situ thromboses are found in the small distal pulmonary arteries. Dysregulation of coagulation, platelet function, and endothelial cells may contribute to a prothrombotic state. There is mixed evidence for the use of anticoagulation or antiplatelet therapy in PAH patients.

Incidence and survival impact of pulmonary arterial hypertension among patients with systemic lupus erythematosus: a nationwide cohort study

Background

No population-based study has investigated the cumulative incidence of pulmonary arterial hypertension (PAH) in patients with newly diagnosed systemic lupus erythematosus (SLE) or the survival impact of PAH in this population.

Method

We used a nationwide database in Taiwan and enrolled incident SLE patients between January 1, 2000, and December 31, 2013. The cumulative incidence of PAH in the SLE patients and the survival of these patients were estimated by the Kaplan-Meier method. Potential predictors of the development of PAH were determined using a Cox proportional hazards regression model.

Results

Of 15,783 SLE patients, 336 (2.13%) developed PAH. The average interval from SLE diagnosis to PAH diagnosis was 3.66 years (standard deviation [SD] 3.36, range 0.1 to 13.0 years). Seventy percent of the patients developed PAH within 5 years after SLE onset. The 3- and 5-year cumulative incidence of PAH were 1.2% and 1.8%, respectively. Systemic hypertension was an independent predictor of PAH occurrence among the SLE patients (adjusted hazard ratio 2.27, 95% confidence interval 1.59–2.97). The 1-, 3-, and 5-year survival rates of SLE patients following the diagnosis of PAH were 87.7%, 76.8%, and 70.1%, respectively.

Conclusions

PAH is a rare complication of SLE and the majority of PAH cases occur within the first 5 years following SLE diagnosis. Systemic hypertension may be a risk factor for PAH development in the SLE population. The overall 5-year survival rate after PAH diagnosis was 70.1%.

Pulmonary arterial hypertension in connective tissue disorders: Pathophysiology and treatment

IMPACT STATEMENT

Our article focuses on the pathogenesis and treatment of CTD-PAH. In the latest ESC/ESR guidelines for PAH, the authors underline that although CTD-PAH should follow the same treatment protocol as idiopathic PAH, the therapeutic approach is more complex and difficult in the former. This review throws light on several peculiar aspects of CTD-PAH and the latest findings in the pathogenesis, namely, the role of inflammation in the maladaptive right ventricle remodeling in SSc-PAH where immunosuppressants are classically believed to be ineffective. Furthermore, we discuss the major critical points in the therapy of CTD-PAH which is one of the strengths of our article. To the best of our knowledge, there are no other reviews that exclusively focus on the pathogenesis and treatment of CTD-PAH patients, with an emphasis on the more critical issues. Thus, it is our contention that our work would be of interest to the readers.

Aicardi goutières syndrome is associated with pulmonary hypertension

While pulmonary hypertension (PH) is a potentially life threatening complication of many inflammatory conditions, an association between Aicardi Goutières syndrome (AGS), a rare genetic cause of interferon (IFN) overproduction, and the development of PH has not been characterized to date. We analyzed the cardiac function of individuals with AGS enrolled in the Myelin Disorders Bioregistry Project using retrospective chart review (n = 61). Additional prospective echocardiograms were obtained when possible (n = 22). An IFN signature score, a marker of systemic inflammation, was calculated through the measurement of mRNA transcripts of type I IFN-inducible genes (interferon signaling genes or ISG). Pathologic analysis was performed as available from autopsy samples. Within our cohort, four individuals were identified to be affected by PH: three with pathogenic gain-of-function mutations in the IFIH1 gene and one with heterozygous TREX1 mutations. All studied individuals with AGS were noted to have elevated IFN signature scores (Mann-Whitney p < .001), with the highest levels in individuals with IFIH1 mutations (Mann-Whitney p < .0001). We present clinical and histologic evidence of PH in a series of four individuals with AGS, a rare interferonopathy. Importantly, IFIH1 and TREX1 may represent a novel cause of PH. Furthermore, these findings underscore the importance of screening all individuals with AGS for PH.

Inflammasomes: a novel therapeutic target in pulmonary hypertension?

Pulmonary hypertension (PH) is a rare, progressive pulmonary vasculopathy characterized by increased mean pulmonary arterial pressure, pulmonary vascular remodelling and right ventricular failure. Current treatments are not curative, and new therapeutic strategies are urgently required. Clinical and preclinical evidence has established that inflammation plays a key role in PH pathogenesis, and recently, inflammasomes have been suggested to be central to this process. Inflammasomes are important regulators of inflammation, releasing the pro-inflammatory cytokines IL-1β and IL-18 in response to exogenous pathogen- and endogenous damage-associated molecular patterns. These cytokines are elevated in PH patients, but whether this is a consequence of inflammasome activation remains to be determined. This review will briefly summarize current PH therapies and their pitfalls, introduce inflammasomes and the mechanisms by which they promote inflammation and, finally, highlight the preclinical and clinical evidence for the potential involvement of inflammasomes in PH pathobiology and how they may be targeted therapeutically. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc.

Pulmonary hypertension in patients with interstitial lung disease

Interstitial lung diseases (ILDs) comprise a broad and heterogeneous group of more than two hundred diseases with common functional characteristics. Their diagnosis and management require a multidisciplinary approach. This multidisciplinary approach involves the assessment of comorbid conditions including pulmonary hypertension (PH) that exerts a dramatic impact on survival. The current World Health Organization (WHO) classification of PH encompasses many of the interstitial lung diseases into WHO Group 3, while sarcoidosis, Pulmonary Langerhans Cell Histiocytosis and lymphangioleiomyomatosis are placed into WHO Group 5 as diseases with unclear or multifactorial mechanisms. Connective tissue diseases could span any of the 5 WHO groups based on the primary phenotype into which they manifest. Interestingly, several challenging phenotypes present with features that overlap between two or more WHO PH groups. Currently, PH-specific treatment is recommended only for patients classified into WHO Group 1 PH. The lack of specific treatment for other groups, including PH in the setting of ILD, reflects the poor outcomes of these patients. Thus, identification of the optimal strategy for ILD patients with PH remains an amenable need. This review article provides a brief overview of biomarkers indicative of vascular remodeling in interstitial lung disease, summarizes the current state of knowledge regarding patients with PH and ILD and highlights future perspectives that remain to be addressed.