Clinical trial NCT05716022: Hiatal Hernia and Pulmonary Involvement
Official title: Hiatal Hernia and Pulmonary Involvement Related to Subclinical Lung Injury and Fibrosis
Study type: OBSERVATIONAL
Overall status: ACTIVE_NOT_RECRUITING
Conditions: Hiatal Hernia
Interstitial Lung Disease
Keywords: Hiatal Hernia
BALF
Interstitial lung Disease
Lead sponsor: University of Virginia
Sponsor class: OTHER
Collaborators: name: American College of Chest Physicians
First posted: 2023-02-08
Enrollment: 100
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: 1. Participants without a clinical diagnosis of pulmonary fibrosis will be recruited from UVA medical center based on the absence of traction bronchiectasis, honeycombing and/or reticular opacities on CT Scan.
2. Case group will be adults who have a clinical diagnosis of hiatal hernia already scheduled to under surgical repair
3. Control group will be adults without a CT diagnosis of hiatal hernia who have been scheduled to undergo Bronchoscopy for lung nodule evaluation.

Brief summary: Patients often present with a significant burden of fibrosis upon diagnosis as there is interest in identifying these individuals earlier in their disease course (i.e., "subclinical disease") where targeted treatments and modification of risk factors may curb their progression to fulminant fibrosing ILD. The investigators have investigated with computed tomography (CT) methods such as interstitial lung abnormalities (ILA) and high attenuation areas (HAAs) that may detect early radiological signs of interstitial lung inflammation and scarring and novel modifiable risk factors that contribute to its pathogenesis. Among adults without clinically-diagnosed pulmonary fibrosis, those with a hiatal hernia will have higher levels of pepsin in bronchoalveolar lavage fluid (BALF) compared with adults without a hiatal hernia. Secondarily, examinination on whether there are differences in other reflux contents from BALF including total bile, and peripheral biomarkers related to lung injury and fibrogenesis which include matrix metalloproteinase-7 (MMP-7), vascular cell adhesion molecule 1 (VCAM-1), and cancer antigen 125 (CA-125).

Detailed description: Fibrosing interstitial lung diseases (ILDs) have significant morbidity and poor overall survival as the investigation of earlier stages of fibrosing ILDs may identify modifiable risk factors and elucidate its pathogenesis. Interstitial lung disease (ILD) constitutes a group of chronic respiratory illnesses that are characterized by repetitive injury to the lung parenchyma that may progress to fibrosis. Fibrosing ILDs, which include idiopathic pulmonary fibrosis (IPF) and other ILD types, can lead to chronic respiratory failure, and poor survival, is the most common indication for lung transplantation. While antifibrotics slow disease progression and may reduce mortality, they carry side effects and are frequently poorly tolerated by patients. Therefore, there is a critical need to identify novel therapeutic targets. Patients often present with a significant burden of fibrosis upon diagnosis as there is interest in identifying these individuals earlier in their disease course (i.e., "subclinical disease") where targeted treatments and modification of risk factors may curb their progression to fulminant fibrosing ILD.

Hiatal hernia and its promotion of gastroesophageal reflux have been implicated as a causal risk factor in pulmonary fibrosis. One potential modifiable risk factor is hiatal hernia and its promotion of gastroesophageal reflux (GER). Gastric materials in the lung induce parenchymal injury and fibrosis in pre-clinical models as GER may be a vehicle of repetitive lung injury that is then followed by aberrant wound healing and eventual fibrosis. Hiatal hernia, which is the protrusion of stomach contents in the thoracic cavity, can promote GER and is more prevalent in adults with pulmonary fibrosis compared with healthy controls and other chronic lung diseases. Further evidence comes from studies in which patients with IPF and other fibrosing ILDs (many of whom had a hiatal hernia) demonstrated elevated levels of pepsin in their bronchoalveolar lavage fluid (BALF), a significant component of reflux and measurable biomarker, compared with healthy controls and is associated with a higher risk of exacerbation. Much of these studies have been case-control and performed in adults with clinically-diagnosed fibrosing ILD which limits causal inferences. It has been hypothesized that fibrosis itself may promote GER due to impaired esophageal sphincter function due to reduced elasticity and more negative intrathoracic pressures. Whether hiatal hernia contributes to subclinical repetitive injury to the lung among adults without clinically-diagnosed ILD is a significant knowledge gap.

Overactivation of the mononuclear phagocyte immune system may contribute to developing fibrosing ILDs and their progression. Single-cell RNA sequencing (scRNA-seq) has accelerated our understanding of fibrosing ILD by identifying biological pathways related to certain cellular populations. Using scRNA-seq, our group and others have demonstrated that overactivation of the mononuclear phagocyte system, a key component of the innate immune system, may be critical in the pathogenesis of IPF with higher populations of monocytes found in the lungs and blood of patients with fibrosis. Higher levels of the absolute monocyte count in the blood are associated with disease progression and worse survival among adults with IPF. The investigators have extended these findings to earlier stages of ILD as higher monocyte counts are associated with more ILA and its progression on CT and a lower forced vital capacity. Notably, adults with ILA have more activated monocytes than those without ILA, suggesting a smoldering activation of innate immunity may prime an individual to developing ILD in combination with other risk factors (i.e., smoking, genetic variants, and hiatal hernia).

Radiologically-detected hiatal hernia is associated with a greater burden of CT interstitial lung abnormalities and worse survival among community-dwelling adults. In a population cohort of U.S. community-dwelling adults, investigators found that the presence of hiatal hernia on CT was associated with more HAAs and their progression over time and more ILA among younger adults. Notably, elevated HAAs on CT were associated with worse survival among those with a hiatal hernia compared with those without a hernia. Our findings suggest that hiatal hernia and its promotion of GER may contribute to subclinical injury and remodeling detected by imaging biomarkers. Whether subclinical abnormalities are detected in the lungs of adults with hiatal hernia remains a major knowledge gap that this study will address by examining BALF contents of adults with hiatal hernia.

Eligibility criteria: Inclusion Criteria:

1. Able to provide written consent.
2. Clinical diagnosis of hiatal hernia and/or gastroesophageal reflux undergoing pre-operative evaluation for surgical repair at the University of Virginia as part of clinical care.
3. 18 years and above.

Exclusion Criteria:

1. Unable to provide written consent.
2. Clinical diagnosis of pulmonary fibrosis.
3. History of hiatal hernia (for control group only).
4. Use of home supplemental oxygen therapy either at rest or exertion.
5. Pregnant Women (will be confirmed as part of standard of care).

Primary outcomes:
measure: Bronchoalveolar lavage fluid pepsin levels
timeFrame: Baseline
Secondary outcomes:
measure: Serum matrix metalloproteinase-7
timeFrame: Baseline
measure: Serum CA-125
timeFrame: Baseline
measure: Serum vascular cell adhesion molecule-1
timeFrame: Baseline
measure: RNA gene expression
timeFrame: Baseline
Other outcomes:
Locations:
city: Charlottesville
country: United States
facility: University of Virginia
state: Virginia
Study officials:
affiliation: University of Virginia
name: John Kim, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: UVA
name: Roselove Asare, MA
role: STUDY_DIRECTOR
affiliation: UVA
name: Yousef Althulth, MD
role: STUDY_DIRECTOR
References:
citation: Kim JS, Kim J, Yin X, Hiura GT, Anderson MR, Hoffman EA, Raghu G, Noth I, Manichaikul A, Rich SS, Smith BM, Podolanczuk AJ, Garcia CK, Barr RG, Prince MR, Oelsner EC. Associations of hiatus hernia with CT-based interstitial lung changes: the MESA Lung Study. Eur Respir J. 2023 Jan 27;61(1):2103173. doi: 10.1183/13993003.03173-2021. Print 2023 Jan.
citation: Kim JS, Axelsson GT, Moll M, Anderson MR, Bernstein EJ, Putman RK, Hida T, Hatabu H, Hoffman EA, Raghu G, Kawut SM, Doyle MF, Tracy R, Launer LJ, Manichaikul A, Rich SS, Lederer DJ, Gudnason V, Hobbs BD, Cho MH, Hunninghake GM, Garcia CK, Gudmundsson G, Barr RG, Podolanczuk AJ. Associations of Monocyte Count and Other Immune Cell Types with Interstitial Lung Abnormalities. Am J Respir Crit Care Med. 2022 Apr 1;205(7):795-805. doi: 10.1164/rccm.202108-1967OC.
citation: Scott MKD, Quinn K, Li Q, Carroll R, Warsinske H, Vallania F, Chen S, Carns MA, Aren K, Sun J, Koloms K, Lee J, Baral J, Kropski J, Zhao H, Herzog E, Martinez FJ, Moore BB, Hinchcliff M, Denny J, Kaminski N, Herazo-Maya JD, Shah NH, Khatri P. Increased monocyte count as a cellular biomarker for poor outcomes in fibrotic diseases: a retrospective, multicentre cohort study. Lancet Respir Med. 2019 Jun;7(6):497-508. doi: 10.1016/S2213-2600(18)30508-3. Epub 2019 Mar 29.
citation: Wijsenbeek M, Cottin V. Spectrum of Fibrotic Lung Diseases. N Engl J Med. 2020 Sep 3;383(10):958-968. doi: 10.1056/NEJMra2005230. No abstract available.
citation: Lee JS, Song JW, Wolters PJ, Elicker BM, King TE Jr, Kim DS, Collard HR. Bronchoalveolar lavage pepsin in acute exacerbation of idiopathic pulmonary fibrosis. Eur Respir J. 2012 Feb;39(2):352-8. doi: 10.1183/09031936.00050911. Epub 2011 Dec 19.
citation: Noth I, Zangan SM, Soares RV, Forsythe A, Demchuk C, Takahashi SM, Patel SB, Strek ME, Krishnan JA, Patti MG, Macmahon H. Prevalence of hiatal hernia by blinded multidetector CT in patients with idiopathic pulmonary fibrosis. Eur Respir J. 2012 Feb;39(2):344-51. doi: 10.1183/09031936.00099910. Epub 2011 Jul 7.