Mean pulmonary arterial pressure as a prognostic indicator in connective tissue disease associated with interstitial lung disease: a retrospective cohort study

Mild elevation of pulmonary vascular resistance predicts mortality regardless of mean pulmonary artery pressure in mild interstitial lung disease

BACKGROUND

Pulmonary hypertension (PH) is defined by elevated mean pulmonary arterial pressure (MPAP), and elevated pulmonary vascular resistance (PVR) reflects pulmonary vascular abnormalities. The clinical significance of non-severe PH in patients with various interstitial lung diseases (ILDs) has not been fully elucidated. We aimed to investigate the clinical significance of MPAP and PVR for mortality in patients with newly diagnosed ILD.

METHODS

We retrospectively analysed consecutive patients with ILD at initial evaluations that included right heart catheterisation from 2007 to 2018. These patients were classified by MPAP and PVR using the 2022 the European Society of Cardiology (ESC)/the European Respiratory Society (ERS) guidelines for PH. The clinical significance of MPAP and PVR for mortality was analysed.

RESULTS

Among 854 patients, 167 (19.6%) had MPAP>20 mm Hg. The proportion of patients with PVR>2 Wood units (WU) among those with MPAP≤20 mm Hg, 202 WU was associated with a higher mortality rate (HR 1.61, 95% CI 1.28 to 2.02, p<0.0001) even in a group with MPAP≤20 mm Hg.

CONCLUSIONS

Mild elevation of PVR was associated with a higher mortality rate in patients with newly diagnosed ILD, even in those with MPAP≤20 mm Hg.

Pulmonary Hypertension Associated with Anti-synthetase Syndrome: A Case Report and Literature Review

Pulmonary hypertension (PH) is a serious condition in which there is an abnormally high pressure in the pulmonary arteries that can occur as a complication of connective tissue diseases. Although the relationship between PH and systemic lupus erythematosus or systemic sclerosis has been well-characterized, PH rarely occurs in patients with anti-synthetase syndrome (ASS), and little is known about the pathophysiology and clinical outcome of patients with ASS-PH. We herein report a patient with anti-Jo-1-positive ASS complicated by PH and discuss the treatment strategy through a review of previously reported cases.

Risk Factors of Postoperative Hospital-Acquired Pneumonia in Patients Undergoing Cardiac Surgery

Background and Objectives. Hospital-acquired pneumonia is one of the complications that may occur in the postoperative period in patients undergoing heart valve surgery, which may result in prolonged hospitalization, development of respiratory failure requiring mechanical ventilation or even death. This study investigated the preoperative risk factors of postoperative pneumonia after heart valve surgery. Materials and Methods: This was a prospective study in a group of consecutive patients with hemodynamically significant valvular heart disease undergoing valve surgery. The primary endpoint at the in-hospital follow-up was hospital-acquired pneumonia after heart valve surgery. Logistic regression analysis was used to assess which variables were predictive of the primary endpoint, and odds ratios (ORdis) were calculated with a 95% confidence interval (CI). Multivariate analysis was based on the results of single-factor logistic regression, i.e., in further steps all statistically significant variables were taken into consideration. Results: The present study included 505 patients. Postoperative pneumonia occurred in 23 patients. The mean time to diagnosis of pneumonia was approximately 3 days after heart valve surgery (±2 days). In multivariate analysis, preoperative level of high-sensitivity Troponin T (hs-TnT) (OR 2.086; 95% CI 1.211-3.593; p = 0.008) and right ventricular systolic pressure (RVSP) (OR 1.043; 95% CI 1.018-1.067; p 0.004) remained independent predictors of the postoperative pneumonia. Of the patients with postoperative pneumonia, 3 patients died due to the development of multiple organ dysfunction syndrome (MODS). Conclusions: Preoperative determination of serum hs-TnT concentration and echocardiographic measurement of the RVSP parameter may be useful in predicting postoperative pneumonia in patients undergoing heart valve surgery.

Pulmonary Hypertension in Interstitial Lung Disease: Management Options to Move Beyond Supportive Care

Purpose of Review

This review delineates current diagnostic and management strategies for pulmonary hypertension due to interstitial lung disease (PH-ILD).

Recent Findings

The INCREASE trial, a phase III multicenter, randomized, placebo-controlled trial demonstrated both improved 6-min walk distance and decreased disease progression with inhaled treprostinil. This pivotal trial led to inhaled treprostinil becoming the first FDA approved medication for treatment of PH-ILD. The availability of this treatment has generated subsequent recommendations for the screening for PH in patients with ILD. As a result, it is becoming increasingly important for clinicians to gain awareness and familiarity with the evolving management options for PH-ILD.

Summary

The management of PH-ILD has its roots in goal-directed treatment of the underlying lung disease. However, recent medication advances and ongoing clinical studies are opening opportunities for more disease-specific treatment.

CT predictors of outcomes in patients with connective tissue disease and progressive lung fibrosis

PURPOSE

Progressive fibrosing interstitial lung disease (PF-ILD) is a phenotype defined by rapid clinical progression towards respiratory failure. While idiopathic pulmonary fibrosis is the archetype of PF-ILD, connective tissue disease associated interstitial lung disease (CTD-ILD) can also manifest as PF-ILD. Few studies have described the value of serial computed tomography (CT) in predicting clinical progression of ILD. We explore which single and serial clinical and radiographic variables, in particular serial CT variables and a novel variable, the right lower lobe anterior bronchial angle (RLL-ABA), best predict mortality, oxygen requirement, hospital admissions, and lung transplant in CTD-ILD.

METHODS

This is a single-center retrospective study of 84 patients with a history of CTD-ILD. Cox survival analysis was used to predict two endpoints, all-cause mortality and composite negative outcomes (CNO): new oxygen requirement, respiratory admission, lung transplant, and death.

RESULTS

On serial CT, change in pulmonary artery (PA) size and RLL-ABA were predictive of mortality and CNO, and change in fibrosis was predictive of mortality alone. On single CT, the extent of fibrosis, PA size, and PA to aorta ratio were predictive of mortality and CNO. Among clinical variables, oxygen requirement, forced vital capacity (FVC), change in FVC, and worsening shortness of breath were predictive of mortality and CNO, and diffusing capacity for carbon monoxide was predictive of mortality alone.

CONCLUSIONS

In addition to clinical and single CT variables, serial CT measurements such as change in extent of fibrosis, PA size, PA to aorta ratio, and RLL-ABA were predictive of mortality and CNO.

Screening Strategies for Pulmonary Hypertension in Patients With Interstitial Lung Disease: A Multidisciplinary Delphi Study

BACKGROUND

Pulmonary hypertension (PH) is a common complication of interstitial lung disease (ILD) and is associated with worse outcomes and increased mortality. Evaluation of PH is recommended in lung transplant candidates, but there are currently no standardized screening approaches. Trials have identified therapies that are effective in this setting, providing another rationale to routinely screen patients with ILD for PH.

RESEARCH QUESTION

What screening strategies for identifying PH in patients with ILD are supported by expert consensus?

STUDY DESIGN AND METHODS

The study convened a panel of 16 pulmonologists with expertise in PH and ILD, and used a modified Delphi consensus process with three surveys to identify PH screening strategies. Survey 1 consisted primarily of open-ended questions. Surveys 2 and 3 were developed from responses to survey 1 and contained statements about PH screening that panelists rated from -5 (strongly disagree) to 5 (strongly agree).

RESULTS

Panelists reached consensus on several triggers for suspicion of PH including the following: symptoms, clinical signs, findings on chest CT scan or other imaging, abnormalities in pulse oximetry, elevations in brain natriuretic peptide (BNP) or N-terminal pro-brain natriuretic peptide (NT-proBNP), and unexplained worsening in pulmonary function tests or 6-min walk distance. Echocardiography and BNP/NT-proBNP were identified as screening tools for PH. Right heart catheterization was deemed essential for confirming PH.

INTERPRETATION

Many patients with ILD may benefit from early evaluation of PH now that an approved therapy is available. Protocols to evaluate patients with ILD often overlap with evaluations for pulmonary hypertension-interstitial lung disease and can be used to assess the risk of PH. Because standardized approaches are lacking, this consensus statement is intended to aid physicians in the identification of patients with ILD and possible PH, and provide guidance for timely right heart catheterization.

Pulmonary hypertension in interstitial lung disease: screening, diagnosis and treatment

PURPOSE OF REVIEW

Pulmonary vascular disease resulting in pulmonary hypertension in the context of interstitial lung disease (PH-ILD) is a common complication that presents many challenges in clinical practice. Despite recent advances, the pathogenetic interplay between parenchymal and vascular disease in ILD is not fully understood. This review provides an overview of the current knowledge and recent advances in the field.

RECENT FINDINGS

Clinical trials employing the phosphodiesterase-5-inhibitor sildenafil delivered negative results whereas riociguat showed harmful effects in the PH-ILD population. More recently, inhaled treprostinil showed positive effects on the primary endpoint (six-min walk-distance) in the largest prospective randomized placebo-controlled trial to date in this patient population. Additionally, a pilot trial of ambulatory inhaled nitric oxide suggests beneficial effects based on the novel endpoint of actigraphy.

SUMMARY

In view of these novel developments this review provides an overview of the status quo of screening, diagnosis and management of pulmonary vascular disease and PH in patients with ILD.

Mildly Elevated Pulmonary Arterial Pressure Is Associated With a High Risk of Progression to Pulmonary Hypertension and Increased Mortality: A Systematic Review and Meta-Analysis

Background

Pulmonary hypertension (PH) is defined as a mean pulmonary arterial pressure (PAP) ≥25 mm Hg measured by right heart catheterization. However, the upper limit of a normal mean PAP is 20 mm Hg. There is a gap between the upper limit of normal and the threshold for diagnosing PH. Therefore, we aimed to investigate whether individuals with a mildly elevated PAP, defined as 20 mm Hg < mean PAP <25 mm Hg, are at an increased risk of progression to PH or mortality than those with a normal PAP.

Methods and Results

We reviewed studies evaluating the risk of progression to PH and/or mortality in individuals with a mildly elevated PAP versus those with a normal PAP. The mean PAP value of each participant was confirmed by right heart catheterization. We reviewed 1213 studies and 8 fulfilled our inclusion criteria. Our results indicated that individuals with a mildly elevated PAP were 1.81 to 2.45 times more likely to progress to PH than individuals with a normal PAP. There was a statistically significant difference in mortality between the mildly elevated PAP and normal PAP groups (hazard ratio, 2.48; 95% CI, 1.69–3.64). We also pooled survival probabilities in each arm to obtain a summary survival curve for each group, and the pooled survival rates in the mildly elevated PAP group were numerically lower than those in the normal PAP group.

Conclusions

Our study revealed that individuals with a mildly elevated PAP were at an increased risk of progression to PH and mortality than those with a normal PAP.

Vascular Pruning on CT and Interstitial Lung Abnormalities in the Framingham Heart Study

BACKGROUND

Pulmonary vascular disease is associated with poor outcomes in individuals affected by interstitial lung disease. The pulmonary vessels can be quantified with noninvasive imaging, but whether radiographic indicators of vasculopathy are associated with early interstitial changes is not known.

RESEARCH QUESTION

Are pulmonary vascular volumes, quantified from CT scans, associated with interstitial lung abnormalities (ILA) in a community-based sample with a low burden of lung disease?

STUDY DESIGN AND METHODS

In 2,386 participants of the Framingham Heart Study, we used CT imaging to calculate pulmonary vascular volumes, including the small vessel fraction (a surrogate of vascular pruning). We constructed multivariable logistic regression models to investigate associations of vascular volumes with ILA, progression of ILA, and restrictive pattern on spirometry. In secondary analyses, we additionally adjusted for diffusing capacity and emphysema, and performed a sensitivity analysis restricted to participants with normal FVC and diffusing capacity.

RESULTS

In adjusted models, we found that lower pulmonary vascular volumes on CT were associated with greater odds of ILA, antecedent ILA progression, and restrictive pattern on spirometry. For example, each SD lower small vessel fraction was associated with 1.81-fold greater odds of ILA (95% CI, 1.41-2.31; P < .0001), and 1.63-fold greater odds of restriction on spirometry (95% CI, 1.18-2.24; P = .003). Similar patterns were seen after adjustment for diffusing capacity for carbon monoxide, emphysema, and among participants with normal lung function.

INTERPRETATION

In this cohort of community-dwelling adults not selected on the basis of lung disease, more severe vascular pruning on CT was associated with greater odds of ILA, ILA progression, and restrictive pattern on spirometry. Pruning on CT may be an indicator of early pulmonary vasculopathy associated with interstitial lung disease.

IPAF should receive early treatment for sharing similar clinical characteristics as CTD-ILD: a report from 273 Chinese patients

OBJECTIVES

The clinical characteristics of interstitial pneumonia with autoimmune features (IPAF) and connective tissue disease interstitial lung disease (CTD-ILD) have not been adequately compared. We compared the clinical characteristics of these two conditions and analyzed the changes in lung function before and after treatment of IPAF.

METHODS

A total of 412 patients were enrolled in the study, and their clinical characteristics were assessed. The treatment-related changes in 12 cases of IPAF were analyzed.

RESULTS

Complete clinical data were available for 126 patients with CTD-ILD and 147 with IPAF. All IPAF patients showed autoantibody positivity. The proportion of patients showing extrapulmonary symptoms in the CTD-ILD group was higher than that in the IPAF group (P < 0.05). Patients with IPAF demonstrated lower P(A-a)O₂ and higher PaO₂ and PaCO₂ than those with CTD-ILD (P < 0.05 for all comparisons). Forced vital capacity (FVC) and diffusing capacity of the lungs for carbon monoxide (D_LCO) in IPAF patients were higher than those in CTD-ILD patients (P = 0.023 for FVC; P = 0.011 for D_LCO). Among patients with IPAF, only the proportions of honeycombing and nodules were lower than those in CTD-ILD patients (P < 0.05). Both FVC and D_LCO values increased after treatment in patients with IPAF (P < 0.05).

CONCLUSION

IPAF showed autoantibody positivity and similar computed tomography (CT) findings as CTD-ILD, and lung function in patients with IPAF improved after immunosuppressive treatment, indicating that IPAF should receive attention and early immunosuppressive treatment like CTD-ILD, even though IPAF exhibits no extrapulmonary symptoms. Key Points • Clinical characteristics of IPAF.

Connective tissue disease-associated interstitial lung disease

BACKGROUND

Connective tissue diseases (CTD) are frequently associated with interstitial lung disease (ILD), significantly impacting their morbidity and mortality.

AIM

Analyze the experience of an autoimmune specialized unit on treating CTD-ILD and characterize the population based on most frequent diseases, imaging patterns, lung function tests results, serology and treatment. Assess mortality and mortality predictors in these patients.

METHODS

Retrospective, descriptive and statistical analysis of the CTD-ILD patients followed up at an autoimmune diseases unit during a 6-year period.

RESULTS

Over the study period, 75 patients with CTD-ILD were treated with a mean follow-up of 49 ± 31 months. The most frequent CTD were systemic sclerosis and rheumatoid arthritis. ILD was diagnosed prior to CTD in 8% of patients and concomitantly in 35%. Nonspecific interstitial pneumonia was the CT pattern in 60% and 35% had an isolated diminished DLCO on lung function tests. Pulmonary hypertension was present in 12% and it was the single most important mortality predictor (OR 14.41, p = 0.006). Corticosteroids are the mainstay of treatment but biologics were prescribed in 39% of the patients (mostly tocilizumab and rituximab). Two scleroderma patients were recently treated with nintedanib.

CONCLUSIONS

ILD is a potential complication of every CTD and can impose a dramatic burden on these patients. The clinical relevance of ILD together with their early expression in the course of the disease underlines the importance of the presence of chest physicians in these units.

Acute exacerbations of fibrosing interstitial lung disease associated with connective tissue diseases: a population-based study

Background

Acute exacerbation (AE) is the major cause of morbidity and mortality in patients with idiopathic pulmonary fibrosis (IPF). AEs also occur in other forms of fibrosing interstitial lung disease (fILD). The clinical features and prognosis of AE patients with connective tissue diseases (CTDs) associated-ILD has not been fully described.

Methods

We retrospectively reviewed 177 patients with either IPF or a characterized CTD-ILD admitted to Nanjing Drum Tower Hospital with an AE from January 2010 to December 2016.

Results

The study cohort included 107 subjects with AE-IPF and 70 cases with AE-CTD-ILD. Female gender, prior use of corticosteroid and immunosupressants, lower serum albumin, higher D-dimer level, TLC% pred, survival, and treatment with immunosupressants and caspofungin were more common in the CTD-ILD group (all p<0.05). The incidences of AE-CTD-ILD and AE-IPF were similar in our single center (p = 0.526). TLC% pred was the risk factor for AE after ILD diagnosis for 1 year in CTD patients (p = 0.018). Log-rank tests showed patients with CTD-ILD had a significantly lower mortality rate compared with IPF patients after AEs (p = 0.029). No significant difference in survival was noted among CTD subgroups (p = 0.353). The survival was negatively correlated with WBC count, LDH and CT score, (p = 0.006, p = 0.013 and p = 0.035, respectively), and positively correlated with PaO₂/FiO₂ ratio (p<0.001) in the CTD-ILD group. WBC count and PO₂/FiO₂ ratio were the independent predictors for survival in AE-CTD-ILD after adjusting for other clinical variates in Cox regression Models (p = 0.038 and p < 0.001, respectively).

Conclusions

The clinical characteristics of patients with AE-CTD-ILD differed from those with AE-IPF, while AE incidences were similar between the two groups. Subjects with AE-CTD-fILD tended to have a better prognosis, and WBC count and PO₂/FiO₂ ratio were the independent survival predictors for these patients.

Mild Pulmonary Hypertension Is Associated With Increased Mortality: A Systematic Review and Meta-Analysis

Background

Recent studies have demonstrated a continuum in clinical risk related to mean pulmonary artery pressure that begins at >19 mm Hg, which is below the traditional threshold used to define pulmonary hypertension (PH) of 25 mm Hg. Because of the implications on patient diagnosis and prognosis, the generalizability and validity of these data need further confirmation.

Methods and Results

Databases were searched from inception through January 31, 2018, to identify studies comparing all‐cause mortality between patients with mildly elevated mean pulmonary artery pressure near but <25 mm Hg versus the referent group. The meta‐analysis included 15 nonrandomized studies and 16 482 patients (7451 [45.2%] with measured or calculated mean pulmonary artery pressure of 19–24 mm Hg by right heart catheterization [n=6037] and echocardiography [n=1414] [mild PH]). The mean duration of follow‐up was 5.2 years. Compared with the referent group, mild PH was associated with an increased risk of mortality (risk ratio, 1.52; 95% confidence interval, 1.32–1.74; P<0.001; I²=47%). Secondary analysis using risk‐adjusted time‐to‐event estimates showed a similar result (hazard ratio, 1.19; 95% confidence interval, 1.09–1.31; P<0.001; I²=42%). The findings were consistent between subgroups of right heart catheterization and echocardiography studies (P_interaction>0.05). There was evidence of publication bias; however, this did not influence the risk estimate (Duval and Tweedie's trim and fill adjusted risk ratio, 1.34; 95% confidence interval, 1.15–1.56).

Conclusions

The risk of mortality is increased in patients with mild PH, defined as measured or calculated mean pulmonary artery pressure >19 mm Hg. These data emphasize a need for diagnosing patients with mild PH with consideration to enrollment in PH clinical studies investigating pharmacological and nonpharmacological interventions to attenuate clinical risk and improve outcomes.

Borderline pulmonary hypertension is associated with exercise intolerance and increased risk for acute exacerbation in patients with interstitial lung disease

Background

Pulmonary hypertension (PH) is traditionally defined as a resting mean pulmonary artery pressure (mPAP) of ≥25 mmHg, while mPAP in the range of 21 to 24 mmHg is recognized as “borderline PH.” Interstitial lung disease (ILD) is complicated by the development of PH, which is known to be linked with exercise intolerance and a poor prognosis. Even though it has recently been recommended that PH is redefined as a mPAP of > 20 mmHg, little is known about the clinical significance of borderline PH in ILD. We evaluated whether borderline PH has an impact on the exercise capacity, risk of acute exacerbation (AE), and mortality in patients with ILD.

Methods

A total of 80 patients with ILD who underwent right heart catheterization (RHC) between November 2013 and October 2016 were included. The patients were divided into 3 groups according to the mPAP values: mPAP ≤20 mmHg (No-PH group; n = 56), 20 < mPAP < 25 mmHg (Bo-PH group; n = 18), and mPAP ≥25 mmHg (PH group; n = 6). The demographic, hemodynamic, spirometric, and 6-min walk test (6MWT) data of the patients were collected. In addition, the 1-year incidence of AEs and 1-year survival of the patients after the initial RHC were also evaluated.

Results

There were no significant differences among the 3 groups in the mean age, pulmonary function parameters or the PaO₂, however, 6-min walk distance was significantly lower in both the Bo-PH and PH groups (p < 0.001 for both) as compared to the No-PH group. The results of the Kaplan-Meier analysis revealed that while there was no significant difference in the 1-year survival rate among the three groups, the 1-year incidence of AEs was significantly higher in both the Bo-PH and PH groups (p < 0.001, p = 0.023, respectively) as compared to the No-PH group.

Conclusions

The current study suggested that borderline PH may be associated with poorer exercise tolerance and an increased risk of AEs in patients with ILD. Therefore, the physicians should pay close attention to the presence of even mild elevation of the mPAP at the initial evaluation in patients with ILD.

Role of SOD3 in silica-related lung fibrosis and pulmonary vascular remodeling

BACKGROUND

Work-place exposure to silica dust may lead to progressive lung inflammation culminating in the development of silicosis, an irreversible condition that can be complicated by onset of pulmonary hypertension (PH). The molecular mechanisms leading to the development of PH and lung fibrosis in response to silica are not well understood. Oxidant/antioxidant imbalance in the lung may promote fibroproliferation and vascular smooth muscle proliferation, ultimately leading to the development of PH. Herein, we analyze the development of PH and lung fibrosis in mice deficient in extracellular superoxide dismutase (SOD3), an enzyme with anti-oxidant activity.

METHODS

PH and silicosis were induced in wild-type and Sod3-/- mice through intratracheal injection of crystalline silica at dose 0.4 g/kg. Pulmonary hypertension and lung fibrosis were characterized by changes in right ventricular systolic pressure (RVSP) and collagen deposition 28 days following silica injections. Vascular remodeling was analyzed using immunohistochemistry and morphometric analysis. The expression of genes were analyzed using qRT-PCR and Western blot.

RESULTS

C57BL6 mice exposed to silica showed attenuated expression of Sod3 in the lung suggesting a protective role for Sod3. Consistent with this, Sod3-/- mice developed more severe fibrotic inflammatory nodules with increased collagen deposition. Furthermore, the expression of genes involved in tissue remodeling (Timp1), fibrotic lesion formation (Fsp1) and inflammatory response (Mcp1) were significantly elevated in Sod3-/- mice compared to Sod3+/+ mice treated with silica. Infiltration of neutrophils and activated macrophages into affected lung was significantly higher in Sod3 deficient mice. In addition, silica produced more profound effects on elevation of RVSP in Sod3-/- compared to wild-type littermate. Increase in RVSP was concomitant with hypertrophy of pulmonary arteries located in silicotic nodules of both mouse strains, however, vascular remodeling in unaffected areas of lung was detected only in Sod3-/- mice.

CONCLUSIONS

Our data suggest that Sod3 and extracellular oxidative stress may play an important role in the development of pneumoconiosis and pulmonary vascular remodeling following exposure to environmental and occupational silica.

Survival of adults with systemic autoimmune rheumatic diseases and pulmonary arterial hypertension after lung transplantation

Objectives

Pulmonary arterial hypertension (PAH) is a major cause of morbidity and mortality in adults with systemic autoimmune rheumatic diseases (ARDs). The aim of this study was to determine whether adults with ARDs and PAH on right-sided heart catheterization (ARD-PAH) have increased mortality following lung transplantation compared with those with PAH not due to an ARD.

Methods

We conducted a retrospective cohort study of 93 adults with ARD-PAH and 222 adults with PAH who underwent lung transplantation in the USA between 4 May 2005 and 9 March 2015 using data from the United Network for Organ Sharing. We examined associations between diagnosis and survival after lung transplantation using stratified Cox models adjusted for potential confounding recipient factors.

Results

Among adults undergoing lung transplantation in the USA, we did not detect a difference in the multivariable-adjusted mortality rate between those with ARD-PAH and those with PAH [hazard ratio 0.75 (95% CI 0.47, 1.19)].

Conclusion

The presence of an ARD was not associated with increased mortality after lung transplantation in adults with PAH.

A scoring system to predict the elevation of mean pulmonary arterial pressure in idiopathic pulmonary fibrosis

Elevated mean pulmonary arterial pressure (MPAP; ≥21 mmHg) is sometimes seen in patients with idiopathic pulmonary fibrosis (IPF) and has an adverse impact upon survival. Although early diagnosis is crucial, there is no established screening tool that uses a combination of noninvasive examinations.We retrospectively analysed IPF patients at initial evaluation from April 2007 to July 2015 and, using logistic regression analysis, created a screening tool to identify elevated MPAP. Internal validation was also assessed for external validity using a bootstrap method.Using right-heart catheterisation (RHC), elevation of MPAP was determined to be present in 55 out of 273 patients. Multivariate models demonstrated that % predicted diffusing capacity of the lung for carbon monoxide (D_LCO) <50%, ratio of pulmonary artery diameter to aorta diameter (PA/Ao) on computed tomography (CT) ≥0.9 and arterial oxygen tension (P_aO2 ) <80 Torr were independent predictors. When we assigned a single point to each variable, the prevalence of elevation of MPAP with a score of zero, one, two or three points was 6.7%, 16.0%, 29.1% and 65.4%, respectively. The area under curve (AUC) for the receiver operating characteristic (ROC) curve was good at 0.757 (95% CI 0.682-0.833).A simple clinical scoring system consisting of % predicted D_LCO, PA/Ao ratio on CT and P_aO2 can easily predict elevation of MPAP in patients with IPF.

Recent advances in connective tissue disease related interstitial lung disease

INTRODUCTION

Interstitial lung disease (ILD) is a common manifestation of connective tissue disease (CTD). Although the majority of patients with CTD-ILD are stable or slowly progressive, a significant group exhibits a more severe and progressive decline. Interstitial pneumonia with autoimmune features (IPAF) describes the subset of patients with interstitial pneumonia who have features suggesting underlying autoimmunity, but whose features fall short of a clear diagnosis of CTD. Areas covered: In this focused review, we discuss recent advances in early detection, prognostic evaluation, and management of autoimmune forms of ILD. Expert commentary: Early detection of ILD and a better understanding of factors that impact prognostication may be helpful when making decisions regarding therapeutic interventions. The treatment of CTD-ILD should be comprehensive, is often fraught with challenges and can be complicated by comorbid conditions and extra-thoracic disease activities. Several large randomized studies have examined the impact of immunosuppressive therapy for CTD-ILD, however, additional studies are needed to determine the optimal treatment strategies. Future studies may provide additional information about the best treatments in patients with IPAF.

CT-determined pulmonary artery to aorta ratio as a predictor of elevated pulmonary artery pressure and survival in idiopathic pulmonary fibrosis

BACKGROUND AND OBJECTIVE

Elevated mean pulmonary artery pressure (mPAP) is a significant prognostic indicator in idiopathic pulmonary fibrosis (IPF). It has been reported that the computed tomography-determined ratio of the diameter of the pulmonary artery to the aorta (PA:A) is correlated with mPAP in various respiratory diseases. However, in patients with IPF, whether the PA:A can be used to predict elevated mPAP and the prognostic value of the PA:A has not been fully evaluated.

METHODS

We conducted a single-centre, observational study of 177 consecutive IPF patients who underwent right heart catheterization. We examined the association between the PA:A and mPAP in these patients, and performed a receiver operating characteristic (ROC) analysis to test the diagnostic accuracy of the PA:A in predicting mPAP > 20 mm Hg (pulmonary hypertension (PH) or borderline PH) in relation to survival.

RESULTS

In a multivariate linear regression analysis, the PA:A, 6-min walk distance and diffusion capacity for carbon monoxide (DL_CO ) % predicted were independent explanatory variables of elevated mPAP (P < 0.0001, P = 0.009 and P = 0.002, respectively). ROC analysis revealed a PA:A > 0.9 to be optimal for predicting mPAP > 20 mmHg (area under the curve (AUC) = 0.75; 95% CI: 0.65-0.84). Patients with a PA:A > 0.9 also had a worse prognosis (P = 0.009).

CONCLUSION

Measurement of the PA:A is a useful and convenient method to predict elevated mPAP in IPF at initial evaluation. Moreover, a PA:A >0.9 was found to be an indicator of worse prognosis.

Interstitial Pneumonia With Autoimmune Features: Value of Histopathology

CONTEXT

- Patients with idiopathic interstitial pneumonia may display evidence of autoimmunity without meeting criteria for a defined connective tissue disease. A recent European Respiratory Society/American Thoracic Society statement proposed research criteria for interstitial pneumonia with autoimmune features (IPAF), which includes findings from the clinical, serologic, and morphologic domains.

OBJECTIVES

- To investigate the importance of histopathologic criteria within the morphologic domain and to report our methodology for identifying these features.

DESIGN

- Patients with idiopathic interstitial pneumonia at the University of Chicago who underwent surgical lung biopsy or lung transplantation were assessed for IPAF histopathologic features, using the initial pathology interpretation in the electronic records. A focused rereview of available slides by a pulmonary pathologist was then performed for patients who failed to meet IPAF criteria on initial pathology assessment.

RESULTS

- Of 422 patients with idiopathic interstitial pneumonia, 176 (41.7%) underwent surgical lung biopsy or lung transplant. Forty-six of those 176 patients (26.1%) met IPAF criteria by initial pathology interpretation and a positive clinical or serologic feature. Of the remaining 130 patients, 73 (56.2%) met either the clinical or serologic domains without meeting the morphologic domain, whereas 36 (27.7%) had slides available for pathology rereview. This rereview demonstrated nonspecific interstitial pneumonia in 8 of 36 patients (22.2%) and lymphoplasmacytic infiltrates in 6 of 36 patients (16.7%), resulting in an additional 7 of 36 patients (19.4%) with idiopathic interstitial pneumonia that met the IPAF criteria. In IPAF, pulmonary vasculopathy was the most prevalent finding (45 of 84; 53.6%) and predicted increased mortality (hazard ratio, 2.5; P = .04).

CONCLUSIONS

- Using a methodological approach to identifying IPAF pathology, we demonstrate a significant increase in the number of patients meeting IPAF criteria because of focused pathologic review and highlight the prognostic value of the IPAF pathologic findings.

Evaluation of computer-based computer tomography stratification against outcome models in connective tissue disease-related interstitial lung disease: a patient outcome study

BACKGROUND

To evaluate computer-based computer tomography (CT) analysis (CALIPER) against visual CT scoring and pulmonary function tests (PFTs) when predicting mortality in patients with connective tissue disease-related interstitial lung disease (CTD-ILD). To identify outcome differences between distinct CTD-ILD groups derived following automated stratification of CALIPER variables.

METHODS

A total of 203 consecutive patients with assorted CTD-ILDs had CT parenchymal patterns evaluated by CALIPER and visual CT scoring: honeycombing, reticular pattern, ground glass opacities, pulmonary vessel volume, emphysema, and traction bronchiectasis. CT scores were evaluated against pulmonary function tests: forced vital capacity, diffusing capacity for carbon monoxide, carbon monoxide transfer coefficient, and composite physiologic index for mortality analysis. Automated stratification of CALIPER-CT variables was evaluated in place of and alongside forced vital capacity and diffusing capacity for carbon monoxide in the ILD gender, age physiology (ILD-GAP) model using receiver operating characteristic curve analysis.

RESULTS

Cox regression analyses identified four independent predictors of mortality: patient age (P < 0.0001), smoking history (P = 0.0003), carbon monoxide transfer coefficient (P = 0.003), and pulmonary vessel volume (P < 0.0001). Automated stratification of CALIPER variables identified three morphologically distinct groups which were stronger predictors of mortality than all CT and functional indices. The Stratified-CT model substituted automated stratified groups for functional indices in the ILD-GAP model and maintained model strength (area under curve (AUC) = 0.74, P < 0.0001), ILD-GAP (AUC = 0.72, P < 0.0001). Combining automated stratified groups with the ILD-GAP model (stratified CT-GAP model) strengthened predictions of 1- and 2-year mortality: ILD-GAP (AUC = 0.87 and 0.86, respectively); stratified CT-GAP (AUC = 0.89 and 0.88, respectively).

CONCLUSIONS

CALIPER-derived pulmonary vessel volume is an independent predictor of mortality across all CTD-ILD patients. Furthermore, automated stratification of CALIPER CT variables represents a novel method of prognostication at least as robust as PFTs in CTD-ILD patients.