Gastroesophageal Reflux Characteristics and Patterns in Patients with Idiopathic Subglottic Stenosis

Idiopathic Subglottic Stenosis in Non-Caucasian Women

Objective

To characterize presentation, disease course, and treatment of idiopathic subglottic stenosis (iSGS) in non-Caucasian women and compare this cohort to the predominantly female, Caucasian patient cohorts identified in the literature.

Study Design

Retrospective review. Results are compared to systematic review of demographics.

Setting

Multiple California institutions from 2008 to 2021.

Methods

Patients with intubation within 2 years of disease or who met exclusion criteria listed in prior publications were excluded. A systematic review of iSGS patient demographics was also completed for comparison.

Results

Of 421 patients with iSGS, 58 self-identified as non-Caucasian women, with 50 ultimately included. Mean age of onset was 45.1 years old (95% confidence interval [CI], 41.5-48.8), and mean age at diagnosis was 47.2 years (95% CI, 43.6-50.7). Mean Charlson comorbidity index was 1.06 (n = 49, 95% CI, 0.69-1.44). At diagnosis, Cotton-Meyer severity scores (documented in n = 45) were Cotton-Myer (CM) I (28.9%), CM II (40%), and CM III (31.1%). Mean age at first endoscopic surgery was 47.7 (95% CI, 44.2-51.3) years. 64% experienced disease recurrence with a median of 11 months between their first and second surgery. Our systematic review identified 60 studies that reported demographic features in patients with iSGS. 95% of pooled patients were Caucasian, while other demographic features were similar to the current cohort.

Conclusion

The non-Caucasian population, almost 14% of this Californian cohort, does not differ from the majority Caucasian population detailed in contemporary literature. This cohort supports the presence of some racial and ethnic heterogeneity in this disease population.

Recurrence Following Endoscopic Laser Wedge Excision and Triple Medical Therapy for Idiopathic Subglottic Stenosis

OBJECTIVE

We present the outcomes for patients with idiopathic subglottic stenosis (iSGS) following their first carbon dioxide laser wedge excision (LWE) procedure, additionally examining the effect of compliance with adjuvant medical therapy (triple therapy) after the operation.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary center.

METHODS

A retrospective review was performed on 183 patients with iSGS following their first LWE and their compliance to adjuvant medical therapy (inhaled corticosteroid, proton pump inhibitor, trimethoprim-sulfamethoxazole) following the operation, with all reviewed to December 31, 2020. The primary outcome variable was median time to recurrence (MTR). Patients were stratified by whether the LWE was their first operation (LWE primary or secondary), by compliance to triple therapy, and by compliance with trimethoprim-sulfamethoxazole. Kaplan-Meier analysis and Cox proportional hazards were used to evaluate the MTR across the stratifications.

RESULTS

An overall 113 patients underwent their first LWE, while 70 received the procedure after having undergone 1 to 13 procedures. The MTR between LWE primary and secondary was 4.6 and 2.9 years, respectively. Adjusted Cox proportional hazards comparing these 2 groups revealed the number of prior operations to be a confounding variable. A statistically increased MTR was demonstrated with greater degrees of medical compliance.

CONCLUSION

LWE conferred an MTR of 4.1 years in the iSGS cohort. The number of prior procedures preceding LWE behaved as a confounding variable. Patients who were completely or partially compliant to triple therapy appear to demonstrate increased intervals prior to recurrence.

Prevalence and incidence of idiopathic subglottic stenosis in southern and central Alberta: a retrospective cohort study

Background

Subglottic stenosis (SGS) is a reportedly rare disease that causes recurrent severe airway obstruction. Etiologies reported for SGS include idiopathic, iatrogenic, autoimmune, congenital, and traumatic, with variable ratios among different centres. From empiric observation, southern and central Alberta was hypothesized to have a disproportionate distribution of SGS driven by increased idiopathic SGS (iSGS) compared to previous literature. Identification of causative agents of iSGS will help understand and guide future management options, so this study aimed to characterize the demographics of SGS subtypes, define prevalence and incidence rates of iSGS in southern Alberta, and geographically analyze for clustering of iSGS prevalence.

Methods

SGS patients from Alberta census divisions No. 1–9 and 15 were retrospectively reviewed. Patients were subtyped according to etiology of SGS and characterized. Idiopathic SGS prevalence and incidence was assessed; prevalence was further geographically segregated by census division and forward sortation area (FSA). Significant clustering patterns were assessed for using a Global Moran’s I analysis.

Results

From 2010 to 2019 we identified 250 SGS patients, who were substantially overrepresented by idiopathic patients (80.4%) compared to autoimmune (10.0%), iatrogenic (7.6%), congenital (1.2%), and traumatic (0.8%). The total iSGS prevalence was 9.28/100,000 with a mean annual incidence rate of 0.71/100,000 per year. Significant clustering was observed (Moran’s index 0.125; z-score 2.832; p = 0.0046) and the highest rates of prevalence were observed in southern Alberta and in rural communities heterogeneously dispersed around Calgary FSAs.

Conclusion

In southern and central Alberta, iSGS patients were disproportionately over-represented in contrast to other subtypes with the highest prevalence in southern Alberta. There was a three-fold higher annual incidence compared to previous literature demonstrating the highest rates of disease reported worldwide. Future research aims to expand the geographical scope and to assess for demographic or environmental differences within significant clusters that may contribute to disease pathophysiology.

Level of evidence

III.

Graphical Abstract

Impact of Adjuvant Medical Therapies on Surgical Outcomes in Idiopathic Subglottic Stenosis

OBJECTIVES/HYPOTHESIS

Adjuvant medications including proton pump inhibitors (PPI), antibiotics (trimethoprim/sulfamethoxazole [TMP-SMX]), and inhaled corticosteroids (ICS) may be prescribed for patients with idiopathic subglottic stenosis (iSGS). We describe medication use with endoscopic dilation (ED) or endoscopic resection with medical treatment (ERMT) and evaluate impact on outcomes.

STUDY DESIGN

International, prospective, 3-year multicenter cohort study of 810 patients with untreated, newly diagnosed, or previously treated iSGS.

METHODS

Post hoc secondary analysis of prospectively collected North American Airway Collaborative data on outcomes linked with adjuvant medication utilization. Primary outcome was time to recurrent operation, evaluated using Kaplan-Meier curves and Cox regression analysis. Secondary outcomes of change in peak expiratory flow (PEF) and clinical chronic obstructive pulmonary disease questionnaire (CCQ) score over 12 months were compared.

RESULTS

Sixty-one of 129 patients undergoing ED received PPI (47%), and 10/143 patients undergoing ED received ICS (7%). TMP-SMX was used by 87/115 patients (76%) undergoing EMRT. PPI use in the ED group did not affect time to recurrence (hazard ratio [HR] = 1.00, 95% confidence interval [CI]: 0.53-1.88; P = .99) or 12-month change in PEF (L/min) (median [interquartile range], 12.0 [10.7-12.2] vs. 8.7 [-5.1 to 24.9]; P = .59), but was associated with 12-month change in CCQ (-0.05 [-0.97 to 0.75] vs. -0.50 [-1.60 to 0.20]; P = .04). ICS did not affect outcome measures. TMP-SMX use in ERMT did not affect time to recurrence (HR = 0.842, 95% CI: 0.2345-3.023; P = .79), PEF at 12 months (75 [68-89] vs. 81 [68-89]; P = .92), or 12-month change in CCQ (0.20 [-1.05 to 0.47] vs. -0.30 [-1.00 to 0.10]; P = .45).

CONCLUSION

There is no standard practice for prescribing adjuvant medications. These data do not support that adjuvant medications prolong time to recurrence or increase PEF. Patients with iSGS and gastroesophageal reflux disease may experience some symptom benefit with PPI.

LEVEL OF EVIDENCE

Level 3 Laryngoscope, 2021.

Idiopathic subglottic stenosis in a young female patient

A previously healthy 30-year-old woman presented with 3 years of progressive shortness of breath and audible wheezing. One year prior to presentation, she developed a chronic non-productive cough. Pulmonary function testing revealed flattened inspiratory and expiratory peaks, characteristic of an extrathoracic fixed tracheal obstruction. Bronchoscopy confirmed subglottic stenosis (SGS). She had no history of intubation, tracheostomy or evidence of a systemic inflammatory illness. She was diagnosed with idiopathic SGS and referred for rigid bronchoscopy with balloon dilatation resulting in improvement in her symptoms.

The role of pepsin in epithelia-mesenchymal transition in idiopathic subglottic stenosis

OBJECTIVES

Idiopathic subglottic stenosis (iSGS) is commonly characterized by laryngeal fibrosis thought to arise by epithelia-mesenchymal transition (EMT) induced by chronic inflammation. Pepsin is a potent inducer of inflammation in the airways during chronic laryngopharyngeal reflux and has been observed in the subglottic mucosa of patients with iSGS, absent in normal mucosa. The aim of this study was to examine the effect of pepsin on mechanisms of EMT in laryngeal cells with implications for iSGS.

STUDY DESIGN

In vitro translational research study.

METHODS

Human laryngeal epithelial cell cultures were exposed to 0.1 mg/mL or 1.0 mg/mL pepsin at pH7 for 24 and 48 hours, or media pH5 ± 0.1 mg/mL pepsin for 10 minutes and harvested after 24 and 48 hours. EMT marker expression was measured by qPCR and enzyme-linked immunosorbent assays. Wound-healing scratch assay was performed on immortalized human vocal fold fibroblasts pretreated with media pH5 ± 0.1 mg/mL pepsin (10 minutes) or continuously treated with media pH7 ± 0.1 to 1 mg/mL pepsin for 24 hours.

RESULTS

Pepsin yielded no effect on MMP1, MMP9, FN1, COL1A1, HAS2, or CDH1 gene expression or matrix metalloproteinase-9 or fibronectin protein expression, either alone or in the presence of weak acid. Pepsin and/or acid produced no effect on fibroblast migration.

CONCLUSION

Whereas pepsin has been shown to be present in the subglottic mucosa of patients with iSGS, this in vitro acute exposure investigation does not provide evidence of a direct causal role for development of fibrosis in subglottic epithelial cell cultures.

LEVELS OF EVIDENCE

NA. Laryngoscope, 130:154-158, 2020.