Laparoscopic fundoplication in patients with end-stage lung disease awaiting transplantation

Gastroesophageal reflux disease in chronic obstructive pulmonary disease

Gastroesophageal reflux disease (GERD) is one of the most common comorbidities of chronic obstructive pulmonary disease (COPD). Decreased lower and upper esophageal sphincter pressures, esophageal dysmotility, high transdiaphragmatic pressure, and decreased saliva secretion have been implicated as mechanisms leading to the development of GERD in COPD. Clinically, comorbid GERD in COPD is reportedly associated with worse symptoms, quality of life, and lung function, as well as a high risk of exacerbations. Aspiration of regurgitation and the cholinergic-mediated esophagobronchial reflex play a significant role in the pathophysiology. Abnormal swallowing reflexes and discoordination of swallowing can worsen aspiration. The diagnosis of GERD is not based on a single criterion; however, various approaches, including questionnaires and endoscopic evaluations, can be widely applied in clinical settings. Due to the increased risk of esophageal and gastric cancers in patients with COPD, the threshold for endoscopic examination should be low. Acid inhibitory agents, such as proton pump inhibitors and histamine H2 receptor antagonists, and prokinetic agents, including mosapride and itopride, are clinically used to treat GERD. Endoscopic fundoplication can be performed in patients with GERD refractory to medical treatment. There is still insufficient evidence, but an increasing number of studies have suggested the clinical efficacy of treatment in patients with COPD and GERD. As GERD is an evaluative and treatable common disease, and access to evaluation and treatment is relatively easy, clinicians should provide adequate care for GERD in the management of COPD.

Abnormal bolus reflux on impedance-pH testing independently predicts 3-year pulmonary outcome and mortality in pulmonary fibrosis

BACKGROUND AND AIM

Gastroesophageal reflux has been associated with idiopathic pulmonary fibrosis (IPF), although the directionality of the relationship has been debated. Data on the value of objective reflux measures in predicting IPF disease progression and mortality remain limited. We aimed to evaluate the association between multichannel intraluminal impedance and pH testing (MII-pH) and 3-year pulmonary outcomes in IPF patients.

METHODS

This was a retrospective cohort study of adults with IPF who underwent pre-lung transplant MII-pH off acid suppression at a tertiary center. Patients were followed for 3 years after MII-pH for poor pulmonary outcomes (hospitalization for respiratory exacerbation or death). A secondary analysis was performed using mortality as outcome of interest. Time-to-event analyses using Kaplan-Meier and Cox regression were performed to evaluate associations between MII-pH and poor outcomes.

RESULTS

One hundred twenty-four subjects (mean age = 61.7 ± 8 years, 62% male) were included. Increased bolus exposure time (BET) on MII-pH was associated with decreased time to poor pulmonary outcomes and death (log-ranked P-value = 0.017 and 0.031, respectively). On multivariable Cox regression analyses controlling for potential confounders including age, sex, smoking history, body mass index, proton pump inhibitor use, baseline pulmonary function, and anti-fibrotic therapy, increased BET was an independent predictor for poor pulmonary outcomes [hazard ratio 3.18 (95% confidence interval: 1.25-8.09), P = 0.015] and mortality [hazard ratio 11.3 (95% confidence interval: 1.37-63.9), P = 0.025] over 3 years.

CONCLUSIONS

Increased BET on MII-pH is an independent predictor of poor pulmonary outcomes and mortality over 3 years in IPF patients. These findings also support a role for gastroesophageal reflux in IPF disease progression and the potential impact of routine reflux testing and treatment.

Investigating the diagnostic utility of high-resolution oesophageal manometry in patients with refractory respiratory symptoms

BACKGROUND

The interaction between the respiratory and gastrointestinal systems, and the role of the latter in the development of respiratory pathology, has been examined with a focus on gastro-oesophageal reflux disease (GORD). However, little data exists examining the link between oesophageal motility and respiratory disease.

AIMS AND OBJECTIVES

In this study, we examined patterns in oesophageal motility using high-resolution oesophageal manometry (HROM) in patients with refractory respiratory symptoms.

METHODS

Data were collected retrospectively for all patients that were investigated using HROM at a single centre for refractory respiratory symptoms between January 1st, 2011-December 1st, 2021. Patients were selected for investigation based on airway reflux symptoms, measured by the Hull Airways Reflux Questionnaire (HARQ).

RESULTS

441 patients were investigated with HROM (64% female, mean age = 56.5 [SD = 13.9]). The commonest diagnoses of these patients were Chronic Cough (77%, n = 339), Asthma (10%, n = 44), and Interstitial Lung Disease (7%, n = 29). The prevalence of oesophageal dysmotility was 66% in our cohort. Those with oesophageal dysmotility had significantly higher HARQ scores than those with normal motility (40.6 vs 35.3, p < 0.001) and there was a significant inverse correlation between HARQ scores and distal contractile integral (DCI), a measure of oesophageal contractility.

CONCLUSIONS

Two-thirds of patients with refractory respiratory symptoms were found to have oesophageal dysmotility on HROM. These findings suggest motility disorders of the oesophagus may contribute to the development and progression of respiratory disease. This study highlights the need for further prospective study of the relationship between oesophageal dysmotility and respiratory disease.

[French practical guidelines for the diagnosis and management of IPF - 2021 update, full version]

BACKGROUND

Since the previous French guidelines were published in 2017, substantial additional knowledge about idiopathic pulmonary fibrosis has accumulated.

METHODS

Under the auspices of the French-speaking Learned Society of Pulmonology and at the initiative of the coordinating reference center, practical guidelines for treatment of rare pulmonary diseases have been established. They were elaborated by groups of writers, reviewers and coordinators with the help of the OrphaLung network, as well as pulmonologists with varying practice modalities, radiologists, pathologists, a general practitioner, a head nurse, and a patients' association. The method was developed according to rules entitled "Good clinical practice" in the overall framework of the "Guidelines for clinical practice" of the official French health authority (HAS), taking into account the results of an online vote using a Likert scale.

RESULTS

After analysis of the literature, 54 recommendations were formulated, improved, and validated by the working groups. The recommendations covered a wide-ranging aspects of the disease and its treatment: epidemiology, diagnostic modalities, quality criteria and interpretation of chest CT, indication and modalities of lung biopsy, etiologic workup, approach to familial disease entailing indications and modalities of genetic testing, evaluation of possible functional impairments and prognosis, indications for and use of antifibrotic therapy, lung transplantation, symptom management, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are aimed at guiding the diagnosis and the management in clinical practice of idiopathic pulmonary fibrosis.

Gastroesophageal Reflux Disease in Idiopathic Pulmonary Fibrosis: Viewer or Actor? To Treat or Not to Treat?

Background: Idiopathic pulmonary fibrosis (IPF) is a rare and severe disease with a median survival of ∼3 years. Several risk factors have been identified, such as age, genetic predisposition, tobacco exposure, and gastro-oesophageal reflux disease (GERD). Prevalence of GERD in IPF is high and may affect 87% of patients, of whom only half (47%) report symptoms. Objective: The aim of this study is to review current evidence regarding the correlation between GERD and IPF and to evaluate the current studies regarding treatments for GERD-IPF. Methods: A review to identify research papers documenting an association between GERD and IPF was performed. Results: We identified several studies that have confirmed the association between GERD and IPF, with an increased acid exposure, risk of gastric aspiration and bile acids levels in these patients. Few studies focused their attention on GERD treatment, showing how antiacid therapy was not able to change IPF evolution. Conclusions: This review investigating the correlation between GERD and IPF has confirmed the hypothesized association. However, further large prospective studies are needed to corroborate and elucidate these findings with a focus on preventative and treatment strategies.

French practical guidelines for the diagnosis and management of idiopathic pulmonary fibrosis - 2021 update. Full-length version

BACKGROUND

Since the latest 2017 French guidelines, knowledge about idiopathic pulmonary fibrosis has evolved considerably.

METHODS

Practical guidelines were drafted on the initiative of the Coordinating Reference Center for Rare Pulmonary Diseases, led by the French Language Pulmonology Society (SPLF), by a coordinating group, a writing group, and a review group, with the involvement of the entire OrphaLung network, pulmonologists practicing in various settings, radiologists, pathologists, a general practitioner, a health manager, and a patient association. The method followed the "Clinical Practice Guidelines" process of the French National Authority for Health (HAS), including an online vote using a Likert scale.

RESULTS

After a literature review, 54 guidelines were formulated, improved, and then validated by the working groups. These guidelines addressed multiple aspects of the disease: epidemiology, diagnostic procedures, quality criteria and interpretation of chest CT scans, lung biopsy indication and procedures, etiological workup, methods and indications for family screening and genetic testing, assessment of the functional impairment and prognosis, indication and use of antifibrotic agents, lung transplantation, management of symptoms, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are intended to guide the diagnosis and practical management of idiopathic pulmonary fibrosis.

Early Postoperative Management of Lung Transplant Recipients

The early postoperative period after lung transplantation is a critical time. Prompt recognition and treatment of primary graft dysfunction can alter long-term allograft function. Cardiovascular, gastrointestinal, renal, and hematologic derangements are common and require close management to limit their negative sequelae.

Idiopathic Pulmonary Fibrosis (an Update) and Progressive Pulmonary Fibrosis in Adults: An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline

Background: This American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana de Tórax guideline updates prior idiopathic pulmonary fibrosis (IPF) guidelines and addresses the progression of pulmonary fibrosis in patients with interstitial lung diseases (ILDs) other than IPF. Methods: A committee was composed of multidisciplinary experts in ILD, methodologists, and patient representatives. 1) Update of IPF: Radiological and histopathological criteria for IPF were updated by consensus. Questions about transbronchial lung cryobiopsy, genomic classifier testing, antacid medication, and antireflux surgery were informed by systematic reviews and answered with evidence-based recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. 2) Progressive pulmonary fibrosis (PPF): PPF was defined, and then radiological and physiological criteria for PPF were determined by consensus. Questions about pirfenidone and nintedanib were informed by systematic reviews and answered with evidence-based recommendations using the GRADE approach. Results:1) Update of IPF: A conditional recommendation was made to regard transbronchial lung cryobiopsy as an acceptable alternative to surgical lung biopsy in centers with appropriate expertise. No recommendation was made for or against genomic classifier testing. Conditional recommendations were made against antacid medication and antireflux surgery for the treatment of IPF. 2) PPF: PPF was defined as at least two of three criteria (worsening symptoms, radiological progression, and physiological progression) occurring within the past year with no alternative explanation in a patient with an ILD other than IPF. A conditional recommendation was made for nintedanib, and additional research into pirfenidone was recommended. Conclusions: The conditional recommendations in this guideline are intended to provide the basis for rational, informed decisions by clinicians.

Antacid Medication and Antireflux Surgery in Patients with Idiopathic Pulmonary Fibrosis: A Systematic Review and Meta-Analysis

Rationale: Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial pneumonia with impaired survival. Previous guidelines recommend antacid medication to improve respiratory outcomes in patients with IPF. Objectives: This systematic review was undertaken during the development of an American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax guideline. The clinical question was, "Should patients with IPF who have documented abnormal gastroesophageal reflux (GER) with or without symptoms of GER disease 1) be treated with antacid medication or 2) undergo antireflux surgery to improve respiratory outcomes?" Methods: Medline, Embase, the Cochrane Central Register of Controlled Trials, and the gray literature were searched through June 30, 2020. Studies that enrolled patients with IPF and 1) compared antacid medication to placebo or no medication or 2) compared antireflux surgery to no surgery were selected. Meta-analyses were performed when possible. Outcomes included disease progression, mortality, exacerbations, hospitalizations, lung function, respiratory symptoms, GER severity, and adverse effects/complications. Results: For antacid medication, when two studies were aggregated, there was no statistically significant effect on disease progression, defined as a 10% or more decline in FVC, more than 50-m decline in 6-minute walking distance, or death (risk ratio [RR], 0.88; 95% confidence interval [CI], 0.76-1.03). A separate study that could not be included in the meta-analysis found no statistically significant effect on disease progression when defined as a 5% or more decline in FVC or death (RR, 1.10; 95% CI, 1.00-1.21) and an increase in disease progression when defined as a 10% or more decline in FVC or death (RR, 1.28; 95% CI, 1.08-1.51). For antireflux surgery, there was also no statistically significant effect on disease progression (RR, 0.29; 95% CI, 0.06-1.26). Neither antacid medications nor antireflux surgery was associated with improvements in the other outcomes. Conclusions: There is insufficient evidence to conclude that antacid medication or antireflux surgery improves respiratory outcomes in patients with IPF, most of whom had not had abnormal GER confirmed. Well-designed and adequately powered prospective studies with objective evaluation for GER are critical to elucidate the role of antacid medication and antireflux surgery for respiratory outcomes in patients with IPF.

Lung Microbiome in Idiopathic Pulmonary Fibrosis and Other Interstitial Lung Diseases

Interstitial lung diseases represent a heterogeneous and wide group of diseases in which factors leading to disease initiation and progression are not fully understood. Recent evidence suggests that the lung microbiome might influence the pathogenesis and progression of interstitial lung diseases. In recent years, the utilization of culture-independent methodologies has allowed the identification of complex and dynamic communities of microbes, in patients with interstitial lung diseases. However, the potential mechanisms by which these changes may drive disease pathogenesis and progression are largely unknown. The aim of this review is to discuss the role of the altered lung microbiome in several interstitial lung diseases. Untangling the host–microbiome interaction in the lung and airway of interstitial lung disease patients is a research priority. Thus, lung dysbiosis is a potentially treatable trait across several interstitial lung diseases, and its proper characterization and treatment might be crucial to change the natural history of these diseases and improve outcomes.

Effect of anti-reflux therapy on pulmonary function in idiopathic pulmonary fibrosis: a systematic review and meta-analysis

Background

Current guideline conditionally recommends regular use of anti-reflux medication in idiopathic pulmonary fibrosis (IPF). However, the effect of anti-reflux therapy in this group remains controversial. We systematically reviewed literatures to evaluate whether anti-reflux therapy could ameliorate pulmonary function in IPF.

Methods

We performed electronic search in PubMed, Embase and CENTRAL (Cochrane Central Register of Controlled Trials) to identify original articles published in English language. We included randomized controlled trials (RCTs) and observational studies regarding anti-reflux therapy on pulmonary function in IPF. Qualitative and quantitative analyses were conducted. In quantitative analysis, the inverse-variance method with fixed-effect model was used to analyze pooled data.

Results

Fifteen studies (2 RCTs and 13 observational studies) including 3,891 patients with IPF were included. Pooled analysis suggested that anti-reflux therapy did not improve forced vital capacity (FVC)% predicted [mean difference (MD) =0.88, 95% confidence interval (CI): −0.22 to 1.98, P=0.12, I² =0%, 8 studies, n=3,076], diffusing capacity of the lung for carbon monoxide (DLCO) % predicted (MD =0.75, 95% CI: −0.13 to 1.62, P=0.10, I² =0%, 8 studies, n=3,073), and FVC decline (MD =0.02, 95% CI: −0.01 to 0.04, P=0.29, I² =17%, 5 studies, n=1,586) in IPF.

Discussion

Anti-reflux therapy may not ameliorate pulmonary function in IPF. However, adequately powered studies are warranted to validate the present findings.

Management of Connective Tissue Disease-Associated Interstitial Lung Disease

The presence of interstitial lung disease (ILD) negatively affects prognosis among patients with an underlying connective tissue disease (CTD). The initial approach to care should determine whether the CTD-ILD needs pharmacologic treatment or not. There is little direct evidence to guide who and how to treat. At present, any severe, active, and/or progressive ILD should be pharmacologically treated. Immunosuppressants and/or corticosteroids are the mainstay of pharmacologic therapy for all CTD-ILDs, whereas antifibrotics may be beneficial in some scenarios. A comprehensive and multidisciplinary approach to management is also an important aspect of patient care.

Gastroesophageal Reflux Disease and Idiopathic Lung Fibrosis. From Heartburn to Lung Transplant, and Beyond

Idiopathic pulmonary fibrosis (IPF) and gastroesophageal reflux disease (GERD) are undoubtedly related. Even though it is not clear yet which one is the primary disease, they certainly interact increasing each other's severity. Symptoms are unreliable to diagnose GERD in patients with IPF, and objective evaluation with pH monitoring and/or bronchoalveolar lavage analysis is mandatory. Pharmacological treatment with proton pump inhibitors (PPIs) may bring control of IPF in few patients, but PPIs do not control reflux but just change the pH of the gastric refluxate. Surgical therapy based on a fundoplication is safe and effective as it controls any type of reflux, independently from the pH of the gastric refluxate. In patients waiting for lung transplantation (if they can tolerate a laparoscopic operation under general anesthesia), a fundoplication before the operation might block the progression of IPF, while after transplantation it might prevent rejection by preventing the bronchiolitis obliterans syndrome.

Surgical treatment of recalcitrant gastroesophageal reflux disease in patients with systemic sclerosis: a systematic review

Introduction

Gastroesophageal reflux disease (GERD) is frequently seen in patients with systemic sclerosis (SSc). Long-standing GERD may cause esophagitis, long-segment strictures, and Barrett’s esophagus and may worsen pre-existing pulmonary fibrosis with an increased risk of end-stage lung disease. Surgical treatment of recalcitrant GERD remains controversial. The purpose of this systematic review was to summarize the current data on surgical treatment of recalcitrant GERD in SSc patients.

Materials and methods

A systematic literature review according to PRISMA and MOOSE guidelines. PubMed, EMBASE, and Web of Science databases were consulted.

Results

A total of 101 patients were included from 7 studies. The age ranged from 34 to 61 years and the majority were females (73.5%). Commonly reported symptoms were heartburn (92%), regurgitation (77%), and dysphagia (74%). Concurrent pulmonary disease was diagnosed in 58% of patients. Overall, 63 patients (62.4%) underwent open fundoplication, 17 (16.8%) laparoscopic fundoplication, 15 (14.9%) Roux en-Y gastric bypass (RYGB), and 6 (5.9%) esophagectomy. The postoperative follow-up ranged from 12 to 65 months. Recurrent symptoms were described in up to 70% and 30% of patients undergoing fundoplication and RYGB, respectively. Various symptoms were reported postoperatively depending on the type of surgical procedures, anatomy of the valve, need for esophageal lengthening, and follow-up.

Conclusions

The treatment of recalcitrant GERD in SSc patients is challenging. Esophagectomy should be reserved to selected patients. Minimally invasive RYGB appears feasible and safe with promising preliminary short-term results. Current evidence is scarce while a definitive indication about the most appropriate surgical treatment is lacking.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00423-021-02118-8.

Current therapies for gastro-oesophageal reflux in the setting of chronic lung disease: state of the art review

The inter-relationship between chronic respiratory disease and reflux disease in the airway reflux paradigm is extremely complex and remains poorly characterised. Reflux disease is reported to cause or contribute to the severity of a number of respiratory tract diseases including laryngeal disorders, sinusitis, chronic cough, asthma, COPD, idiopathic pulmonary fibrosis, cystic fibrosis, bronchiectasis and bronchiolitis obliterans post lung transplant. It is now appreciated that reflux disease is not simply caused by liquid acid reflux but rather by a variety of chemical refluxates originating from the stomach and duodenum due to a number of different mechanisms. Reflux disease can be challenging to diagnose, particularly proving its role in the causation of direct respiratory epithelial damage. Significant advances in oesophageal assessment and gastric biomarkers have emerged in recent years as our understanding increases. There are a number of treatments available for reflux disease, both medical and surgical, but there is a paucity of large randomised trials to evaluate their efficacy in the setting of chronic respiratory disease. Everyday clinical practice, however, informs us that treatment failure in reflux disease is common. This clinical review summarises associations between reflux disease in the setting of chronic respiratory diseases and examines available evidence regarding potential therapeutic strategies.

Gastro-oesophageal reflux disease is prevalent among patients with chronic respiratory disease. A number of medical and surgical treatment options are available for GORD. This review examines available evidence in the setting of chronic lung disease.https://bit.ly/34TcMJS

Esophageal Evaluation for Patients Undergoing Lung Transplant Evaluation: What Should We Do for Evaluation and Management

Lung transplantation is a high-risk, but lifesaving, procedure for patients with end-stage lung disease. Although 1-year survival is high, long-term survival is not nearly as high, due mainly to acute and chronic rejection. Bronchiolitis obliterans syndrome is the most common type of chronic rejection and often leads to poor outcomes. For this reason, esophageal testing in the lung transplant population has become a major issue, and this article discusses the evidence behind esophageal testing, the importance of esophageal dysmotility gastroesophageal reflux disease, both acidic and nonacidic reflux, and aspiration and the treatment of these findings.

Extraesophageal syndrome of gastroesophageal reflux: relationships with lung disease and transplantation outcome

Gastroesophageal reflux disease (GERD) is prevalent and may be associated with both esophageal and extraesophageal syndromes, which include various pulmonary conditions. GERD may lead to pulmonary complications through the "reflux" (aspiration) or "reflex" (refluxate-triggered, vagally mediated airway spasm) mechanisms. While GERD may cause or worsen pulmonary disorders, changes in respiratory mechanics due to lung disease may also increase reflux. Typical esophageal symptoms are frequently absent and objective assessment with reflux monitoring is often needed for diagnosis. Impedance monitoring should be considered in addition to traditional pH study due to the involvement of both acidic and weakly acidic/nonacidic reflux. Antireflux therapy may improve outcomes of some pulmonary complications of GERD, although careful selection of a candidate is paramount to successful outcomes. Further research is needed to identify the optimal testing strategy and patient phenotypes that would benefit from antireflux therapy to improve pulmonary outcomes.

Brazilian guidelines for the pharmacological treatment of idiopathic pulmonary fibrosis. Official document of the Brazilian Thoracic Association based on the GRADE methodology

Idiopathic pulmonary fibrosis (IPF) is a form of chronic interstitial lung disease of unknown cause, which predominantly affects elderly men who are current or former smokers. Even though it is an uncommon disease, it is of great importance because of its severity and poor prognosis. In recent decades, several pharmacological treatment modalities have been investigated for the treatment of this disease, and the classic concepts have therefore been revised. The purpose of these guidelines was to define evidence-based recommendations regarding the use of pharmacological agents in the treatment of IPF in Brazil. We sought to provide guidance on the practical issues faced by clinicians in their daily lives. Patients of interest, Intervention to be studied, Comparison of intervention and Outcome of interest (PICO)-style questions were formulated to address aspects related to the use of corticosteroids, N-acetylcysteine, gastroesophageal reflux medications, endothelin-receptor antagonists, phosphodiesterase-5 inhibitors, pirfenidone, and nintedanib. To formulate the PICO questions, a group of Brazilian specialists working in the area was assembled and an extensive review of the literature on the subject was carried out. Previously published systematic reviews with meta-analyses were analyzed for the strength of the compiled evidence, and, on that basis, recommendations were developed by employing the Grading of Recommendations Assessment, Development and Evaluation approach. The authors believe that the present document represents an important advance to be incorporated in the approach to patients with IPF, aiming mainly to improve its management, and can become an auxiliary tool for defining public policies related to IPF.

Idiopathic pulmonary fibrosis and GERD: links and risks

Gastroesophageal reflux disease (GERD) and idiopathic pulmonary fibrosis (IPF) are two pathological conditions often strictly related, even if a clear relationship of causality has not been demonstrated. GERD is a frequent comorbidity in IPF patients, as demonstrated using combined multichannel intraluminal impedance-pH, despite being mostly clinically silent. According to that, it has been hypothesized that microaspiration of gastric material may play a fundamental role in the fibrotic transformation of pulmonary parenchyma. In contrast, it cannot be excluded that IPF may favor GERD by increasing the negative intrathoracic pressure. Therefore, this relationship is uncertain as well as not univocal. Nevertheless, the latest international guidelines recommend the use of proton pump inhibitors (PPIs) in IPF based on several data showing that PPIs can stabilize lung function, reduce disease flares and hospitalizations. On the contrary, recent studies not only question the relevance of these results, but also associate the use of PPIs with an increased risk of lung infections and a negative prognostic outcome. The aim of this review is to analyze the possible links between GERD and IPF and their possible therapeutic implications, trying to translate this scientific evidence into useful information for clinical practice.

Diagnosing complications and co-morbidities of fibrotic interstitial lung disease

Introduction: Interstitial lung diseases (ILDs) represent a heterogeneous group of rare disorders that include more than 200 entities, mostly associated with high mortality. In recent years, the progress regarding the understanding of the pathogenesis of these diseases led to the approval of specific treatments. In ILDs, the presence of comorbidities has a significant impact on the quality of life and the survival of patients and, therefore, their diagnosis and treatment has a pivotal role in management and could improve overall outcome. Areas covered: We discuss key diagnostic issues with regard to the most frequent comorbidities in ILDs. Treatment options are also discussed as the decision to investigate more definitively in order to identify specific comorbidities (including lung cancer, pulmonary hypertension, GE reflux, and obstructive sleep apnoea) is critically dependent upon whether comorbidity-specific treatments are likely to be helpful in individual patients, judged on a case by case basis. Expert opinion: The extent to which clinicians proactively pursue the identification of comorbidities depends on realistic treatment goals in individual patients.

Idiopathic pulmonary fibrosis: unmasking cryptogenic environmental factors

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease of unknown origin that is associated with high morbidity and mortality. In this perspective, we briefly review the current understanding of the pathophysiology of IPF and the importance of environmental triggers as a precipitant of disease. We discuss occult intrinsic and extrinsic environmental factors that affect the lung microenvironment and may contribute to the development and progression of disease. The clinical implications of this framework need to be further elucidated, because prompt identification and elimination of occult exposures may represent a novel treatment modality.

The pathogenetic mechanisms of cough in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis is a peripheral subpleural interstitial lung disorder limited to the lung not involving the airways. It has a poor prognosis (survival less than 5 years) and commonly an interstitial pneumonia radiological pattern. Patients complain of a chronic dry cough in 80% of cases. A cough is often the first symptom of this rare disease, preceding dyspnea by years, and is associated with a poor prognosis, high dyspnea scores and low FVC percentages. The pathogenetic mechanisms leading to coughing in IPF are unclear. This review focuses on recent evidence of cough pathophysiology in this disease. Gastroesophageal reflux may promote coughing in IPF patients; bile salts and pepsin may be abundant in BAL of these patients, inducing overproduction of TGF-β by airway epithelial cells and mesenchymal transition with fibroblast recruitment/activation and extracellular matrix deposition. Patients have an enhanced cough reflex to capsaicin and substance P with respect to control subjects. Moreover, patients with the MUC5B polymorphism show more severe coughing as MUC5B encodes for the dominant mucin in the honeycomb cysts of IPF patients. Comorbidities, including asthma, gastroesophageal reflux, hypersensitivity pneumonitis, bronchiectasis, chronic obstructive pulmonary disease and emphysema, can induce coughing in IPF patients. There is no clear explanation of the causes of coughing in IPF. Further research into the pathophysiology of IPF and the pathogenetic mechanisms of coughing is necessary to improve survival and quality of life.

Reflux aspiration in lungs of dogs with respiratory disease and in healthy West Highland White Terriers

BACKGROUND

Gastroesophageal reflux and microaspiration (MA) of gastric juice are associated with various human respiratory diseases but not in dogs.

OBJECTIVE

To detect the presence of bile acids in bronchoalveolar lavage fluid (BALF) of dogs with various respiratory diseases.

ANIMALS

Twenty-seven West Highland White Terriers (WHWTs) with canine idiopathic pulmonary fibrosis (CIPF), 11 dogs with bacterial pneumonia (BP), 13 with chronic bronchitis (CB), 9 with eosinophilic bronchopneumopathy (EBP), 19 with laryngeal dysfunction (LD), 8 Irish Wolfhounds (IWHs) with previous BPs, 13 healthy WHWTs, all privately owned dogs, and 6 healthy research colony Beagles METHODS: Prospective cross-sectional observational study with convenience sampling of dogs. Bile acids were measured by mass spectrometry in BALF samples. Total bile acid (TBA) concentration was calculated as a sum of 17 different bile acids.

RESULTS

Concentrations of TBA were above the limit of quantification in 78% of CIPF, 45% of BP, 62% of CB, 44% of EBP, 68% of LD, and 13% of IWH dogs. In healthy dogs, bile acids were detected less commonly in Beagles (0/6) than in healthy WHWTs (10/13). Concentrations of TBA were significantly higher in CIPF (median 0.013 μM, range not quantifiable [n.q.]-0.14 μM, P < .001), healthy WHWTs (0.0052 μM, n.q.-1.2 μM, P = .003), LD (0.010 μM, n.q.-2.3 μM, P = .015), and CB (0.0078 μM, n.q.-0.073 μM, P = .018) groups compared to Beagles (0 μM, n.q.).

CONCLUSION AND CLINICAL IMPORTANCE

These results suggest that MA occurs in various respiratory diseases of dogs and also in healthy WHWTs.

Gastroesophageal Reflux Disease in Idiopathic Pulmonary Fibrosis: Uncertainties and Controversies

The mechanisms of idiopathic pulmonary fibrosis (IPF), a rare, devastating disease with a median survival of 3-5 years, are not fully understood. Gastroesophageal reflux disease (GERD) is a frequent comorbidity encountered in IPF. Hypothetically, GERD-associated microaspiration may lead to persistent inflammation impairing lung infrastructure, thereby possibly accelerating the progression of IPF. IPF may increase intrathoracic pressure, which can aggravate GERD and vice versa. On the basis of the possible beneficial effects of antireflux or antacid therapy on lung function, acute exacerbation, and survival, the recent international IPF guideline recommends antacid therapies for patients with IPF, regardless of symptomatic GERD. However, due to newer conflicting data, several national guidelines do not support this recommendation. Elucidation of these questions by further clinical and bench-to-bedside research may provide us with rational clinical diagnostic and therapeutic approaches concerning GERD in IPF. The present review aims to discuss the latest data on the controversial association of IPF and GERD.

Comorbidities of IPF: How do they impact on prognosis

Idiopathic Pulmonary Fibrosis (IPF) is a severe parenchymal lung disease characterized by an intense deposition of collagen in the interstitial spaces. The introduction of anti-fibrotic drugs increased patients' life expectancy highlighting the role of comorbidities in patients' management and prognosis. IPF is frequently associated with other diseases mainly because of its onset during middle age and sometimes because of the presence of common pathogenic pathways such as in the case of lung cancer. Comorbidities may differently influence prognosis of IPF patients. However, except for major impacting ones as LC, PH and cardiovascular diseases, data exploring their impact on prognosis are still few and sometimes conflicting highlighting the need of new large and targeted studies. In this review we discuss the current knowledge on the most common comorbidities associated with IPF (cardiovascular diseases, pulmonary hypertension, lung cancer, emphysema, gastro-oesophageal reflux and depression), focusing on their prognostic role.

Laparoscopic anti-reflux surgery for the treatment of idiopathic pulmonary fibrosis (WRAP-IPF): a multicentre, randomised, controlled phase 2 trial

BACKGROUND

Abnormal acid gastro-oesophageal reflux (GER) is hypothesised to play a role in progression of idiopathic pulmonary fibrosis (IPF). We aimed to determine whether treatment of abnormal acid GER with laparoscopic anti-reflux surgery reduces the rate of disease progression.

METHODS

The WRAP-IPF trial was a randomised controlled trial of laparoscopic anti-reflux surgery in patients with IPF and abnormal acid GER recruited from six academic centres in the USA. We enrolled patients with IPF, abnormal acid GER (DeMeester score of ≥14·7; measured by 24-h pH monitoring) and preserved forced vital capacity (FVC). We excluded patients with a FVC below 50% predicted, a FEV₁/FVC ratio of less than 0·65, a history of acute respiratory illness in the past 12 weeks, a body-mass index greater than 35, and known severe pulmonary hypertension. Concomitant therapy with nintedanib and pirfenidone was allowed. The primary endpoint was change in FVC from randomisation to week 48, in the intention-to-treat population with mixed-effects models for repeated measures. This trial is registered with ClinicalTrials.gov, number NCT01982968.

FINDINGS

Between June 1, 2014, and Sept 30, 2016, we screened 72 patients and randomly assigned 58 patients to receive surgery (n=29) or no surgery (n=29). 27 patients in the surgery group and 20 patients in the no surgery group had an FVC measurement at 48 weeks (p=0·041). Intention-to-treat analysis adjusted for baseline anti-fibrotic use demonstrated the adjusted rate of change in FVC over 48 weeks was -0·05 L (95% CI -0·15 to 0·05) in the surgery group and -0·13 L (-0·23 to -0·02) in the non-surgery group (p=0·28). Acute exacerbation, respiratory-related hospitalisation, and death was less common in the surgery group without statistical significance. Dysphagia (eight [29%] of 28) and abdominal distention (four [14%] of 28) were the most common adverse events after surgery. There was one death in the surgery group and four deaths in the non-surgery group.

INTERPRETATION

Laparoscopic anti-reflux surgery in patients with IPF and abnormal acid GER is safe and well tolerated. A larger, well powered, randomised controlled study of anti-reflux surgery is needed in this population.

FUNDING

US National Institutes of Health National Heart, Lung and Blood Institute.

The effect of anti-acid therapy on survival in idiopathic pulmonary fibrosis: a methodological review of observational studies

International treatment guidelines for idiopathic pulmonary fibrosis (IPF) give a conditional recommendation for anti-acid therapy. As some observational studies reported discrepant findings on the effectiveness of anti-acid therapy on mortality in IPF, we reviewed all studies to evaluate whether immortal time bias explains these discrepancies.We searched the Embase and MEDLINE databases up to July 2017 for observational studies assessing the effectiveness of anti-acid therapy on mortality in IPF. Hazard ratios of mortality with anti-acid therapy were pooled across studies using random-effect models, stratified by the presence of immortal time bias.We identified 10 observational studies. Four of the five studies reporting beneficial effects of anti-acid therapy use on mortality were affected by immortal time bias (pooled hazard ratio 0.46; 95% CI 0.30-0.69), while it was unclear whether the fifth was affected. The five studies that avoided immortal time bias reported no effect of anti-acid therapy on mortality (pooled hazard ratio 0.99; 95% CI 0.81-1.22).The apparent beneficial effects of anti-acid therapy on mortality in patients with IPF result from observational studies affected by immortal time bias. Thus, the effectiveness of anti-acid therapy in IPF remains uncertain and needs to be reassessed with more accurate observational study methods and randomised trials.

Aspiration Pneumonia and Related Syndromes

Aspiration is a syndrome with variable respiratory manifestations that span acute, life-threatening illnesses, such as acute respiratory distress syndrome, to chronic, sometimes insidious, respiratory disorders such as aspiration bronchiolitis. Diagnostic testing is limited by the insensitivity of histologic testing, and although gastric biomarkers for aspiration are increasingly available, none have been clinically validated. The leading mechanism for microaspiration is thought to be gastroesophageal reflux disease, largely driven by the increased prevalence of gastroesophageal reflux across a variety of respiratory disorders, including chronic obstructive pulmonary disease, asthma, idiopathic pulmonary fibrosis, and chronic cough. Failure of therapies targeting gastric acidity in clinical trials, in addition to increasing concerns about both the overuse of and adverse events associated with proton pump inhibitors, raise questions about the precise mechanism and causal link between gastroesophageal reflux and respiratory disease. Our review summarizes key aspiration syndromes with a focus on reflux-mediated aspiration and highlights the need for additional mechanistic studies to find more effective therapies for aspiration syndromes.

Proton Pump Inhibitors in IPF: A Call for Clinical Trials

The recent FDA approval of two drugs, pirfenidone and nintedanib, for the treatment of idiopathic pulmonary fibrosis (IPF) has fueled interest in the development of additional drugs to treat the disease or its major clinical complications including cough and acute exacerbations. Since 2015, there are at least a dozen active interventional studies that are testing the efficacy of novel pharmacotherapies, exercise or stem cells in modifying the disease process in IPF. Additionally, there are combinatorial studies evaluating the effectiveness of pirfenidone or nintedanib in combination with other agents. However, there remains an urgent need for clinical trials to prospectively evaluate the efficacy of existing drugs with promising retrospective data, such as proton pump inhibitors (PPIs), in IPF. Several retrospective cohorts have provided tantalizing data supporting the beneficial effect of PPIs in patients with well-defined IPF. This review provides the general outlook of pharmacotherapies in IPF, and highlights preclinical and retrospective clinical data to make a case for randomized controlled clinical trials of PPIs in IPF.

Treatment of Gastroesophageal Reflux in Patients With Idiopathic Pulmonary Fibrosis: A Systematic Review and Meta-Analysis

BACKGROUND

Gastroesophageal reflux (GER) is common in patients with idiopathic pulmonary fibrosis (IPF) and has been proposed as a potential contributor to disease progression and exacerbation. Whether treatment of GER improves health outcomes in patients with IPF is controversial. Our objective was to review the efficacy and safety of GER treatments in IPF.

METHODS

We performed a systematic review and meta-analysis, using MEDLINE, Embase, Central (Cochrane Central Register of Controlled Trials), and ClinicalTrials.gov. These databases were searched from their inception, and Google Scholar and conference abstracts were searched until September 2017 without language restrictions for randomized and observational studies evaluating the effects of pharmacologic or nonpharmacologic treatment. Primary outcomes were IPF-related mortality and all-cause mortality. Evidence was evaluated according to GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. The study was registered with PROSPERO (#CRD42017076257).

RESULTS

Thirteen observational studies were identified through the search strategy, and eight were included in the meta-analysis. Pharmacologic treatment of GER was associated with a significant reduction in IPF-related mortality as compared with no GER treatment (unadjusted risk: HR, 0.60; 95% CI, 0.38-0.97; P = .04; I² = 0%; three studies; N = 2,033; adjusted risk: HR, 0.45; 95% CI, 0.24-0.84; P = .01; I² = 0%; three studies; N = 2,033) but not all-cause mortality (unadjusted: HR, 0.73; 95% CI, 0.45-1.2; P = .22; I² = 46%; three studies; N = 1,316; adjusted: HR, 0.76; 95% CI, 0.31-1.84; P = .54; I² = 89%; four studies; N = 1,585). The quality of evidence for these outcomes was low.

CONCLUSIONS

Low-quality evidence suggests pharmacologic treatment of GER is associated with a reduction in IPF-related mortality but not overall mortality. Randomized trials of antacid therapy in IPF are needed.

Microbiome in interstitial lung disease: from pathogenesis to treatment target

PURPOSE OF REVIEW

This review summarizes current knowledge of the role of the lung microbiome in interstitial lung disease and poses considerations of the microbiome as a therapeutic target.

RECENT FINDINGS

Although historically considered sterile, bacterial communities have now been well documented in lungs in health and disease. Studies in idiopathic pulmonary fibrosis (IPF) suggest that increased bacterial burden and/or abundance of potentially pathogenic bacteria may drive disease progression, acute exacerbations, and mortality. More recent work has highlighted the interaction between the lung microbiome and the innate immune system in IPF, strengthening the argument for the role of both host and environment interaction in disease pathogenesis. In support of this, studies of interstitial lung diseases other than IPF suggest that it may be the host immune response, which shapes the microbiome in these diseases. Some clinical and mouse model data also suggest that the lung microbiome may represent a therapeutic target, via antibiotic administration, immunization against pathogenic organisms, or treatment directed at gastroesophageal reflux.

SUMMARY

Evidence suggests that the lung microbiome may serve as a prognostic biomarker, a therapeutic target, or provide an explanation for disease pathogenesis in IPF.

Gastroesophageal Reflux and Idiopathic Pulmonary Fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease of unknown origin that affects about 40,000 new patients every year in the USA. Albeit the disease is labelled as idiopathic, it is thought that pathologic reflux, often silent, plays a role in its pathogenesis through a process of microaspiration of gastric contents.

AIMS

The aim of this study was to review the available evidence linking reflux to IPF, and to study the effect of medical and surgical therapy on the natural history of this disease.

RESULTS

Medical therapy with acid-reducing medications controls the production of acid and has some benefit. However, reflux and aspiraion of weakly acidic or alkaline gastric contents can still occur. Better results have been reported after laparoscopic anti-reflux surgery, as this form of therapy re-establishes the competence of the lower esophageal sphincter, therefore stopping any type of reflux.

CONCLUSIONS

A phase II NIH study in currently in progress in the USA to determine the role of antireflux surgery in patients with GERD and IPF. The hope is that this simple operations might alter the natural history of IPF, avoiding progression and the need for lung transplantation.

Comorbid Conditions in Idiopathic Pulmonary Fibrosis: Recognition and Management

Idiopathic pulmonary fibrosis (IPF), a fibrosing interstitial pneumonia of unknown etiology, primarily affects older adults and leads to a progressive decline in lung function and quality of life. With a median survival of 3-5 years, IPF is the most common and deadly of the idiopathic interstitial pneumonias. Despite the poor survivorship, there exists substantial variation in disease progression, making accurate prognostication difficult. Lung transplantation remains the sole curative intervention in IPF, but two anti-fibrotic therapies were recently shown to slow pulmonary function decline and are now approved for the treatment of IPF in many countries around the world. While the approval of these therapies represents an important first step in combatting of this devastating disease, a comprehensive approach to diagnosing and treating patients with IPF remains critically important. Included in this comprehensive assessment is the recognition and appropriate management of comorbid conditions. Though IPF is characterized by single organ involvement, many comorbid conditions occur within other organ systems. Common cardiovascular processes include coronary artery disease and pulmonary hypertension (PH), while gastroesophageal reflux and hiatal hernia are the most commonly encountered gastrointestinal disorders. Hematologic abnormalities appear to place patients with IPF at increased risk of venous thromboembolism, while diabetes mellitus (DM) and hypothyroidism are prevalent metabolic disorders. Several pulmonary comorbidities have also been linked to IPF, and include emphysema, lung cancer, and obstructive sleep apnea. While the treatment of some comorbid conditions, such as CAD, DM, and hypothyroidism is recommended irrespective of IPF, the benefit of treating others, such as gastroesophageal reflux and PH, remains unclear. In this review, we highlight common comorbid conditions encountered in IPF, discuss disease-specific diagnostic modalities, and review the current state of treatment data for several key comorbidities.

[Idiopatic pulmonary fibrosis: A new paradigm]

Idiopathic pulmonary fibrosis ((IPF) is the most common disease from a group of interstitial lung diseases, which occurs mainly in middle-aged and elderly people. Over the past decade, there have been considerable changes in approaches to diagnosing and treating IPF. The paper presents an update on the epidemiology of IPF, the results of new studies of its pathogenesis, and main approaches to diagnosing the disease. In addition, there is new evidence on therapy for IPF.

Idiopathic Pulmonary Fibrosis: Novel Concepts of Proton Pump Inhibitors as Antifibrotic Drugs

The prevalence of abnormal acid gastroesophageal reflux (GER) is higher in patients with idiopathic pulmonary fibrosis (IPF) than in matched control subjects. Several studies demonstrated that more than one-third of patients with IPF have abnormal esophageal acid exposures. In addition, many of these studies indicate that the majority of patients with IPF have silent reflux with no symptoms of GER. Findings of abnormal reflux persist in a large proportion of patients with IPF placed on antacid therapy such as proton pump inhibitors (PPIs). This seemingly paradoxical observation suggests that either patients with IPF are somehow resistant to PPI-based intervention or PPIs are inherently unable to suppress acid GER. By contrast, patients with IPF who undergo Nissen fundoplication surgery are effectively relieved from the complications of GER, and retrospective studies suggest improved lung function. Retrospective, anecdotal data suggest a beneficial role of PPIs in IPF including stabilization of lung function, reduction in episodes of acute exacerbation, and enhanced longevity. The recent evidence-based guidelines for treatment of IPF approved conditional recommendation of PPIs for all patients with IPF regardless of their GER status. Recently, we have reported that PPIs possess antiinflammatory and antifibrotic activities by directly suppressing proinflammatory cytokines, profibrotic proteins, and proliferation of lung fibroblasts. Our study provides an alternative explanation for the beneficial effect of PPIs in IPF. In this Perspective, we reviewed emerging progress on antifibrotic effect of PPIs using IPF as a disease model. In addition, we summarized surgical and pharmacological interventions for GER and their downstream effect on lung physiology.

Lung disease severity in idiopathic pulmonary fibrosis is more strongly associated with impedance measures of bolus reflux than pH parameters of acid reflux alone

BACKGROUND

Gastroesophageal reflux (GER) has been associated with idiopathic pulmonary fibrosis (IPF). Pathogenesis may be related to chronic micro-aspiration. We aimed to assess objective measures of GER on multichannel intraluminal impedance and pH study (MII-pH) and their relationship with pulmonary function testing (PFT) results, and to compare the performance of pH/acid reflux parameters vs corresponding MII/bolus parameters in predicting pulmonary dysfunction in IPF.

METHODS

This was a retrospective cohort study of IPF patients undergoing prelung transplant evaluation with MII-pH off acid suppression, and having received PFT within 3 months. Patients with prior fundoplication were excluded. Severe pulmonary dysfunction was defined using diffusion capacity of the lung for carbon monoxide (DLCO) ≤40%. Six pH/acid reflux parameters with corresponding MII/bolus reflux measures were specified a priori. Multivariate analyses were applied using forward stepwise logistic regression. Predictive value of each parameter for severe pulmonary dysfunction was calculated by area-under-the-receiver-operating-characteristic-curve or c-statistic.

KEY RESULTS

Forty-five subjects (67% M, age 59, 15 mild-moderate vs 30 severe) met criteria for inclusion. Patient demographics and clinical characteristics were similar between pulmonary dysfunction groups. Abnormal total reflux episodes and prolonged bolus clearance time were significantly associated with pulmonary dysfunction severity on univariate and multivariate analyses. No pH parameters were significant. The c-statistic of each pH parameter was lower than its MII counterpart in predicting pulmonary dysfunction.

CONCLUSIONS & INFERENCES

MII/bolus reflux, but not pH/acid reflux, was associated with pulmonary dysfunction in prelung transplant patients with IPF. MII-pH may be more valuable than pH testing alone in characterizing GER in IPF.

Role of gastroesophageal reflux disease in lung transplantation

Lung transplantation is one of the highest risk solid organ transplant modalities. Recent studies have demonstrated a relationship between gastroesophageal reflux disease (GERD) and lung transplant outcomes, including acute and chronic rejection. The aim of this review is to discuss the pathophysiology, evaluation, and management of GERD in lung transplantation, as informed by the most recent publications in the field. The pathophysiology of reflux-induced lung injury includes the effects of aspiration and local immunomodulation in the development of pulmonary decline and histologic rejection, as reflective of allograft injury. Modalities of reflux and esophageal assessment, including ambulatory pH testing, impedance, and esophageal manometry, are discussed, as well as timing of these evaluations relative to transplantation. Finally, antireflux treatments are reviewed, including medical acid suppression and surgical fundoplication, as well as the safety, efficacy, and timing of such treatments relative to transplantation. Our review of the data supports an association between GERD and allograft injury, encouraging a strategy of early diagnosis and aggressive reflux management in lung transplant recipients to improve transplant outcomes. Further studies are needed to explore additional objective measures of reflux and aspiration, better compare medical and surgical antireflux treatment options, extend follow-up times to capture longer-term clinical outcomes, and investigate newer interventions including minimally invasive surgery and advanced endoscopic techniques.

Antacid Therapy and Disease Progression in Patients with Idiopathic Pulmonary Fibrosis Who Received Pirfenidone

BACKGROUND

Gastroesophageal reflux disease is a potential risk factor for idiopathic pulmonary fibrosis (IPF) progression; however, the impact of antacid therapy (AAT) is under debate.

OBJECTIVE

To evaluate the effect of AAT on IPF progression in pirfenidone-treated patients.

METHODS

This post hoc analysis included patients with IPF who received pirfenidone in 3 trials (CAPACITY [PIPF-004/PIPF-006] and ASCEND [PIPF-016]). Pulmonary function, exercise tolerance, survival, hospitalizations, and adverse events (AEs) over 52 weeks were analyzed by baseline AAT use. Disease progression was defined as a decrease in forced vital capacity (FVC) of ≥10%, a decrease in 6-min walking distance of ≥50 m, or death over 1 year.

RESULTS

Of 623 patients, 44% received AAT. No significant differences were found at 52 weeks (AAT versus non-AAT, respectively) in disease progression (24.9 vs. 30.6%; p = 0.12), all-cause mortality rate (2.9 vs. 4.0%; p = 0.47), IPF-related mortality rate (1.1 vs. 2.0%; p = 0.37), all-cause hospitalization rate (16.1 vs. 18.3%; p = 0.48), or mean change in percent FVC (-2.7 vs. -3.1%; p = 0.44). A relative, but not absolute, FVC decline of ≥10% favored AAT (15 vs. 22%; p = 0.03). Severe gastrointestinal AEs (3.7 vs. 0.9%; p = 0.015) and severe pulmonary infections (3.7 vs. 1.1%; p = 0.035) were more frequent with AAT.

CONCLUSIONS

AAT and pirfenidone had outcomes comparable to those of pirfenidone alone in patients with IPF, underscoring the need for prospective trials to elucidate the role of AAT with or without antifibrotic drugs as a treatment for IPF.