Association of Air Pollutant Exposure and Sinonasal Histopathology Findings in Chronic Rhinosinusitis

Multi-omic integration reveals alterations in nasal mucosal biology that mediate air pollutant effects on allergic rhinitis

BACKGROUND

Allergic rhinitis is a common inflammatory condition of the nasal mucosa that imposes a considerable health burden. Air pollution has been observed to increase the risk of developing allergic rhinitis. We addressed the hypotheses that early life exposure to air toxics is associated with developing allergic rhinitis, and that these effects are mediated by DNA methylation and gene expression in the nasal mucosa.

METHODS

In a case-control cohort of 505 participants, we geocoded participants' early life exposure to air toxics using data from the US Environmental Protection Agency, assessed physician diagnosis of allergic rhinitis by questionnaire, and collected nasal brushings for whole-genome DNA methylation and transcriptome profiling. We then performed a series of analyses including differential expression, Mendelian randomization, and causal mediation analyses to characterize relationships between early life air toxics, nasal DNA methylation, nasal gene expression, and allergic rhinitis.

RESULTS

Among the 505 participants, 275 had allergic rhinitis. The mean age of the participants was 16.4 years (standard deviation = 9.5 years). Early life exposure to air toxics such as acrylic acid, phosphine, antimony compounds, and benzyl chloride was associated with developing allergic rhinitis. These air toxics exerted their effects by altering the nasal DNA methylation and nasal gene expression levels of genes involved in respiratory ciliary function, mast cell activation, pro-inflammatory TGF-β1 signaling, and the regulation of myeloid immune cell function.

CONCLUSIONS

Our results expand the range of air pollutants implicated in allergic rhinitis and shed light on their underlying biological mechanisms in nasal mucosa.

The Impact of Acute Peri-operative Particulate Matter Exposure on Endoscopic Sinus Surgery Outcomes: A Preliminary Multi-site Investigation

BACKGROUND

Environmental exposures have been postulated to play an important role in the pathophysiology of chronic rhinosinusitis (CRS). Particulate matter (PM) is one of the most widely studied ambient air pollutants, but its peri-operative impact on CRS is unknown.

OBJECTIVE

To determine the effect of acute, peri-operative PM exposure on outcomes after endoscopic sinus surgery (ESS).

METHODS

Participants with CRS who self-selected ESS were prospectively enrolled. The 22-item SinoNasal Outcome Test (SNOT-22) and Medical Outcomes Study Questionnaire Short-Form 6-D (SF-6D) health utility values scores were recorded. Using residence zip codes, a secondary analysis of patient exposure to PM <2.5 μm and <10 μm (PM2.5 and PM10, respectively) was performed for the month of surgery utilizing data from Environmental Protection Agency air quality monitors. Spearman's correlation coefficients (ρ), 95% confidence intervals (CIs), and effect estimates (β) were used to determine the magnitudes of association. Simple, multivariate regression analysis was also completed.

RESULTS

One hundred and seven patients from four geographically unique institutions across the US were enrolled with a follow-up of 6 months. Patients with higher peri-operative PM2.5 exposure had less improvement in their SNOT-22 scores after ESS compared to those with less exposure using both univariate analysis (ρ = 0.26, 95% CI: 0.08, 0.43; P  =  .01) and after covariate adjustment with multivariate analysis (B  =  1.06, 95% CI: 0.001, 2.14, P  =  .05). Similar associations were not found with SF-6D outcomes or with PM10 as an exposure of interest. No significant correlations were found between peri-operative PM levels and Lund-Kennedy endoscopy scores post-operatively.

CONCLUSION

Preliminary data from this pilot study reveal that PM exposure at the time of ESS may negatively associate with post-operative improvement in sinonasal quality-of-life. Larger, population-based studies with more standardized PM exposure windows are needed to confirm the clinical significance of the present findings.

How Does Climate Change Affect the Upper Airway?

There is mounting evidence that climate change is having a significant influence on exacerbations of airway disease. We herein explore the physical factors of carbon dioxide, temperature increases, and humidity on intensifying allergen and fungal growth, and worsening air quality. The direct influence of these factors on promoting allergic rhinitis, chronic rhinosinusitis, and allergic fungal rhinosinusitis is reviewed.

Does air pollutant exposure impact disease severity or outcomes in chronic rhinosinusitis?

BACKGROUND

Poor air quality increases the risk of developing chronic rhinosinusitis (CRS) and other airway diseases. However, there are limited data on air pollutants and CRS-specific disease severity. We assessed the impact of air pollutants on sinonasal-specific and general quality-of-life (QOL) measures in a multi-institutional cohort of patients with CRS.

METHODS

Participants with CRS were prospectively enrolled in a cross-sectional study and self-selected continued appropriate medical therapy or endoscopic sinus surgery (ESS). The 22-item SinoNasal Outcome Test (SNOT-22) and Medical Outcomes Study Questionnaire Short-Form 6-D (SF-6D) health utility value scores were recorded. Patient exposure to air pollutants was determined using residence zip codes. Unadjusted group differences were compared, and correlation coefficients were evaluated to identify the magnitude of bivariate association.

RESULTS

A total of 486 patients were enrolled and followed for a mean of 6.9 (standard deviation [SD] ± 2.3) months. Pollutant exposure did not significantly correlate with baseline SNOT-22 or SF-6D scores. Revision ESS was associated with higher median fine particulate matter (PM2.5; Δ = 0.12, [95% confidence interval {CI}: 0.003, 0.234]; p = 0.006) compared with primary surgery. PM2.5, PM10, and nitrogen dioxide concentrations (μg/m3) did not correlate with change in total SNOT-22 or SF-6D scores after treatment. Nevertheless, sulfur dioxide (SNOT-22: ρ = -0.121 [95% CI: -0.210, -0.030]; p = 0.007; SF-6D: ρ = 0.095 [95% CI: 0.002, 0.186]; p = 0.04) and carbon monoxide (SNOT-22: ρ = -0.141 [95% CI: -0.230, 0.050]; p = 0.002) exposure did correlate with these outcome measures.

CONCLUSION

Air pollutants may contribute, at least in part, to disease severity in CRS; future investigation is needed to further elucidate the nature of this relationship.

The Relationship between Fine Particle Matter (PM2.5) Exposure and Upper Respiratory Tract Diseases

PM2.5 is one of the most harmful components of airborne pollution and includes particles with diameters of less than 2.5 μm. Almost 90% of the world's population lives in areas with poor air quality exceeding the norms established by the WHO. PM2.5 exposure affects various organs and systems of the human body including the upper respiratory tract which is one of the most prone to its adverse effects. PM2.5 can disrupt nasal epithelial cell metabolism, decrease the integrity of the epithelial barrier, affect mucociliary clearance, and alter the inflammatory process in the nasal mucosa. Those effects may increase the chance of developing upper respiratory tract diseases in areas with high PM2.5 pollution. PM2.5's contribution to allergic rhinitis (AR) and rhinosinusitis was recently thoroughly investigated. Numerous studies demonstrated various mechanisms that occur when subjects with AR or rhinosinusitis are exposed to PM2.5. Various immunological changes and alterations in the nasal and sinonasal epithelia were reported. These changes may contribute to the observations that exposure to higher PM2.5 concentrations may increase AR and rhinosinusitis symptoms in patients and the number of clinical visits. Thus, studying novel strategies against PM2.5 has recently become the focus of researchers' attention. In this review, we summarize the current knowledge on the effects of PM2.5 on healthy upper respiratory tract mucosa and PM2.5's contribution to AR and rhinosinusitis. Finally, we summarize the current advances in developing strategies against PM2.5 particles' effects on the upper respiratory tract.

The Impact of Ambient and Wildfire Air Pollution on Rhinosinusitis and Olfactory Dysfunction

PURPOSE OF REVIEW

With increasing industrialization, exposure to ambient and wildfire air pollution is projected to increase, necessitating further research to elucidate the complex relationship between exposure and sinonasal disease. This review aims to summarize the role of ambient and wildfire air pollution in chronic rhinosinusitis (CRS) and olfactory dysfunction and provide a perspective on gaps in the literature.

RECENT FINDINGS

Based on an emerging body of evidence, exposure to ambient air pollutants is correlated with the development of chronic rhinosinusitis in healthy individuals and increased symptom severity in CRS patients. Studies have also found a robust relationship between long-term exposure to ambient air pollutants and olfactory dysfunction. Ambient air pollution exposure is increasingly recognized to impact the development and sequelae of sinonasal pathophysiology. Given the rising number of wildfire events and worsening impacts of climate change, further study of the impact of wildfire-related air pollution is a crucial emerging field.

The Effects of Wildfire Smoke on Asthma and Allergy

PURPOSE OF REVIEW

To review the recent literature on the effects of wildfire smoke (WFS) exposure on asthma and allergic disease, and on potential mechanisms of disease.

RECENT FINDINGS

Spatiotemporal modeling and increased ground-level monitoring data are allowing a more detailed picture of the health effects of WFS exposure to emerge, especially with regard to asthma. There is also epidemiologic and some experimental evidence to suggest that WFS exposure increases allergic predisposition and upper airway or sinonasal disease, though much of the literature in this area is focused more generally on PM2.5 and is not specific for WFS. Experimental evidence for mechanisms includes disruption of epithelial integrity with downstream effects on inflammatory or immune pathways, but experimental models to date have not consistently reflected human disease in this area. Exposure to WFS has an acute detrimental effect on asthma. Potential mechanisms are suggested by in vitro and animal studies.

Individual exposure of ambient particulate matters and eosinophilic chronic rhinosinusitis with nasal Polyps: Dose-Response, mediation effects and recurrence prediction

PURPOSE

We evaluated the association between ambient particulate matter (PM) exposure and eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP), and predicted the CRSwNP recurrence risk using machine learning algorithms.

METHODS

In total, 1,086 patients with CRSwNP were recruited from nine hospitals in China during 2014-2019. The average annual concentrations of ambient PMs before surgery were assessed using satellite-based daily concentrations of PM_2.5 and PM₁₀ for a 1 × 1-km² area. Linear regression and logistic regression models were used to evaluate the associations of PM exposure with eosinophilia and risks of eosinophilic CRSwNPs. In addition, mediation effect analysis was used to validate the interrelationships of the aforementioned factors. Finally, machine learning algorithms were used to predict the recurrence risks of CRSwNPs.

RESULTS

There was a significantly increased risk of eosinophilic CRSwNPs with each 10 μg/m³ increase in PM_s, with odds ratios (ORs) of 1.039 (95% confidence interval [CI] = 1.007-1.073) for PM₁₀ and 1.058 (95% CI = 1.007- 1.112) for PM_2.5. Eosinophils had a significant mediation effect, which accounted for 52% and 35% of the relationships of CRSwNP recurrence with PM₁₀ and PM_2.5, respectively. Finally, we developed a naïve Bayesian model to predict the risk of CRSwNP recurrence based on PM exposure, inflammatory data, and patients' demographic factors.

CONCLUSIONS

Increased PM exposure is associated with an increased risk of eosinophilic CRSwNP in China. Therefore, patients with eosinophilic CRSwNP should reduce PM exposure to mitigate its harmful impacts.

The Impact of Social Determinants and Air Pollution on Healthcare Disparities in Chronic Rhinosinusitis With Nasal Polyps

BACKGROUND/OBJECTIVE

Multiple factors affect healthcare disparities in chronic rhinosinusitis (CRS) with and without nasal polyps. These factors include access to care, economic burdens to treatment, and differences in air pollution and air quality. In this paper, we will discuss how socioeconomic status, race, and air pollution burden influence healthcare disparities in the diagnosis and treatment outcomes of chronic rhinosinusitis with nasal polyps (CRSwNP).

METHODS

A literature search was performed via PubMed for articles related to CRSwNP, healthcare disparities, race, socioeconomic status, and air pollution in September 2022. Original studies from 2016 to 2022, landmark articles, and systematic reviews were included. We summarized these articles to cohesively discuss factors contributing to healthcare disparities in CRSwNP.

RESULTS

Literary search produced 35 articles. Individual factors such as socioeconomic status, race, and air pollution influence CRSwNP severity and treatment outcomes. Correlations were noted with socioeconomic status, race, and air pollution exposure and CRS severity and post-surgical outcomes. Air pollution exposure was also associated with histopathologic changes in CRSwNP. Lack of access to care was a notable contributor to healthcare disparities in CRS.

CONCLUSION

Healthcare disparities in the diagnosis and treatment of CRSwNP differentially affect racial minorities and individuals of lower socioeconomic status. Increased air pollution exposure in areas of lower socioeconomic status is a compounding factor. Clinician advocacy for greater healthcare access and reductions in environmental exposures for patients, among other societal changes, may help improve disparities.

Lactose and Galactose Promote the Crystallization of Human Galectin-10

Galectin-10 (Gal-10) forms Charcot-Leyden crystals (CLCs), which play a key role in the symptoms of asthma and allergies and some other diseases. Gal-10 has a carbohydrate-binding site; however, neither the Gal-10 dimer nor the CLCs can bind sugars. To investigate the monomer-dimer equilibrium of Gal-10, high-performance size-exclusion chromatography (SEC) was employed to separate serial dilutions of Gal-10 with and without carbohydrates. We found that both the dimerization and crystallization of Gal-10 were promoted by lactose/galactose binding. A peak position shift for the monomer was observed after treatment with either lactose or galactose, implying that the polarity of the monomer was reduced by lactose/galactose binding. Further experiments indicated that alkaline conditions of pH 8.8 mimicked the lactose/galactose-binding environment, and the time interval between monomers and dimers in the chromatogram decreased from 0.8 min to 0.4 min. Subsequently, the electrostatic potential of the Gal-10 monomers was computed. After lactose/galactose binding, the top side of the monomer shifted from negatively charged to electrically neutral, allowing it to interact with the carbohydrate-binding site of the opposing subunit during dimerization. Since lactose/galactose promotes the crystallization of Gal-10, our findings implied that dairy-free diets (free of lactose/galactose) might be beneficial to patients with CLC-related diseases.

Moving toward Equitable Care for Sleep Apnea in the United States: Positive Airway Pressure Adherence Thresholds: An Official American Thoracic Society Policy Statement

Background: Positive airway pressure (PAP) is a highly effective treatment for obstructive sleep apnea (OSA), but adherence limits its efficacy. In addition, coverage of PAP by CMS (Centers for Medicare & Medicaid Services) and other insurers in the United States depends on adherence. This leaves many beneficiaries without PAP, disproportionally impacting non-white and low socioeconomic position patients with OSA and exacerbating sleep health disparities. Methods: An inter-professional, multidisciplinary, international committee with various stakeholders was formed. Three working groups (the historical policy origins, impact of current policy, and international PAP coverage models) met and performed literature reviews and discussions. Using surveys and an iterative discussion-based consensus process, the policy statement recommendations were created. Results: In this position paper, we advocate for policy change to CMS PAP coverage requirements to reduce inequities and align with patient-centered goals. We specifically call for eradicating repeat polysomnography, eliminating the 4-hour rule, and focusing on patient-oriented outcomes such as improved sleepiness and sleep quality. Conclusions: Modifications to the current policies for PAP insurance coverage could improve health disparities.

Oxidative Stress and Air Pollution: Its Impact on Chronic Respiratory Diseases

Redox regulation participates in the control of various aspects of metabolism. Reactive oxygen and nitrogen species participate in many reactions under physiological conditions. When these species overcome the antioxidant defense system, a distressed status emerges, increasing biomolecular damage and leading to functional alterations. Air pollution is one of the exogenous sources of reactive oxygen and nitrogen species. Ambient airborne particulate matter (PM) is important because of its complex composition, which includes transition metals and organic compounds. Once in contact with the lungs' epithelium, PM components initiate the synthesis of inflammatory mediators, macrophage activation, modulation of gene expression, and the activation of transcription factors, which are all related to the physiopathology of chronic respiratory diseases, including cancer. Even though the pathophysiological pathways that give rise to the development of distress and biological damage are not fully understood, scientific evidence indicates that redox-dependent signaling pathways are involved. This article presents an overview of the redox interaction of air pollution inside the human body and the courses related to chronic respiratory diseases.

Climate change, the environment, and rhinologic disease

BACKGROUND

The escalating negative impact of climate change on our environment has the potential to result in significant morbidity of rhinologic diseases.

METHODS

Evidence based review of examples of rhinologic diseases including allergic and nonallergic rhinitis, chronic rhinosinusitis, and allergic fungal rhinosinusitis was performed.

RESULTS

The lower socioeconomic population, including historically oppressed groups, will be disproportionately affected.

CONCLUSIONS

We need a systematic approach to improve healthcare database infrastructure and funding to promote diverse scientific collaboration to address these healthcare needs.

The role of hypoxia in the pathophysiology of chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is a chronic inflammatory disease of the nasal cavity characterized by excessive nasal mucus secretion and nasal congestion. The development of CRS is related to pathological mechanisms induced by hypoxia. Under hypoxic conditions, the stable expression of both Hypoxia inducible factor-1 (HIF-1) α and HIF-2α are involved in the immune response and inflammatory pathways of CRS. The imbalance in the composition of nasal microbiota may affect the hypoxic state of CRS and perpetuate existing inflammation. Hypoxia affects the differentiation of nasal epithelial cells such as ciliated cells and goblet cells, induces fibroblast proliferation, and leads to epithelial-mesenchymal transition (EMT) and tissue remodeling. Hypoxia also affects the proliferation and differentiation of macrophages, eosinophils, basophils, and mast cells in sinonasal mucosa, and thus influences the inflammatory state of CRS by regulating T cells and B cells. Given the multifactorial nature in which HIF is linked to CRS, this study aims to elucidate the effect of hypoxia on the pathogenic mechanisms of CRS.

Association between Concentration of Air Pollutants and Prevalence of Inflammatory Sinonasal Diseases: A Nationwide Cross-sectional Study

BACKGROUND

Air pollution is a serious health concern and affects inflammatory sinonasal diseases such as allergic rhinitis (AR) and chronic rhinosinusitis (CRS). Clarifying the relationship between air pollutants and upper respiratory diseases could help the patients.

OBJECTIVE

To evaluate the association between the concentration of air pollutants and the prevalence of AR and CRS among South Koreans.

METHODS

In this cross-sectional study, nationwide data were reviewed for participants of the Korean National Health and Nutrition Examination Survey (KNHANES) 2008 to 2012. Participants were surveyed with health questionnaires, examined with endoscopies by otolaryngologists, and tested with serum immunoglobulin E levels. The concentrations of sulfur dioxide (SO₂), nitrogen dioxide (NO₂), ozone (O₃), and particulate matter with aerodynamic diameters ≤10 µm (PM₁₀) were measured in 16 areas of South Korea. Air pollutant concentrations of geographic districts were matched to each participant's residence. Logistic regression analysis was performed.

RESULTS

Among 27 863 eligible adults, 3359 and 1606 participants had AR or CRS, respectively. In multivariable logistic regression analysis for AR, PM₁₀ showed statistically significant results (odds ratio [OR] = 1.145, 95% confidence interval [CI] = 1.042-1.258). No air pollutants showed statistically significant differences in the prevalence of CRS. In AR, PM₁₀ (OR = 1.458, 95% CI = 1.201-1.770) was associated with endoscopic findings of watery rhinorrhea, whereas SO₂ (OR = 1.202, 95% CI = 1.100-1.313) was associated with pale mucosa.

CONCLUSION

The prevalence of AR was significantly associated with PM₁₀ concentration. In patients with AR, endoscopic findings of watery rhinorrhea were associated with PM₁₀. However, CRS was not associated with the air pollutant concentrations. Lower concentration of PM₁₀ might help managing the clinical symptoms in patients of AR.

Environmental air pollution and chronic rhinosinusitis: A systematic review

Objective

Chronic rhinosinusitis (CRS) is a highly prevalent and burdensome disease. The pathophysiology is not fully elucidated, but environmental pollutants have been suggested to impact the inflammatory component of the disease process. This review aims to summarize the role of environmental pollution in CRS onset and disease severity.

Methods

A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines. PubMed, EMBASE, Cochrane Library, Web of Science, and Scopus databases were queried in August 2021. Original articles reporting on air pollution exposure in CRS were included. Other forms of sinonasal disease were excluded.

Results

Literature search produced 11,983 articles, of which 10 met inclusion criteria. Outcomes evaluated included incidence/prevalence, disease severity, quality of life, and histopathologic/microbial changes. Air pollutant exposure was associated with higher odds of CRS, particularly with particulate matter (PM) exposure. Increasing air pollution exposure was also associated with worsened disease severity and detectable histopathologic changes. Impact on quality of life was less clear.

Conclusion

Air pollution (particularly PM) is correlated with CRS incidence/prevalence and disease severity, with evidence of histopathologic changes in CRS tissue samples. Further research is warranted to better understand the mechanisms by which air pollution components may cause CRS and type 2 inflammation.

Level of Evidence

3a

Recent evidence suggests a role for air pollution in the onset and severity of CRS, most notably with relation to PM_2.5 exposure. This systematic review supports previous in vitro and in vivo models of pollution in CRS. This study further adds to the existing body of literature demonstrating the many negative health impacts of exposure to air pollution, including impacts on upper airway disease, lower airway disease, cardiac disease, and overall morbidity and mortality.

Air Pollution Exposure Affects Severity and Cellular Endotype of Chronic Rhinosinusitis With Nasal Polyps

OBJECTIVES/HYPOTHESIS

Air pollution has emerged as an important environmental risk factor for chronic rhinosinusitis (CRS) progression. This study assessed exposure to five types of air pollution (PM_2.5/10 , SO₂ , NO₂ , CO, O₃ ) and explored their effects on CRS with nasal polyps (CRSwNP) severity and endotype.

STUDY DESIGN

Retrospective cohort study.

METHODS

Air pollution data from monitoring sites in Beijing were obtained to assess individual air pollution exposure. Outcomes of CRSwNP (n = 282) including Lund-Mackay (L-M) score, Lund-Kennedy (L-K) score, visual analogue scale (VAS) score and nasal patency/airflow resistance and so on were measured to analyze correlations with air pollution and compare groups with different exposure types. Multivariable-adjusted binary logistic regression was used to determine potential air pollution risk factors of the endotype of eosinophilic CRSwNP (ECRSwNP).

RESULTS

Short-term exposures to PM_2.5/10 , SO₂ , CO, NO₂ , and O₃ were weak but significantly associated with increased L-M scores. Short-term exposures to PM₁₀ , CO, and NO₂ were correlated with increased VAS headache/facial pain scores. The L-M scores of the group of the highest PM_2.5 (≥150 μg/m³ ) exposure were significantly higher than those of control group. For each increased unit of the average concentration of PM_2.5 , there was a 1.047-fold (95% confidence interval, 1.005-1.091) increased risk of the endotype of ECRSwNP.

CONCLUSIONS

Air pollution exposure exacerbated CRSwNP severity and PM_2.5 could be a risk factor for endotype of ECRSwNP, suggesting the role of air pollution in CRSwNP pathogenesis.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Role of Environmental Air Pollution in Chronic Rhinosinusitis

PURPOSE OF REVIEW

Chronic rhinosinusitis (CRS) is a highly prevalent disease with large social and financial burdens. The pathophysiology is multifactorial. Environmental pollutants have been suggested to play a role in the inflammatory component of the disease process.

RECENT FINDINGS

Recent work has focused on exposure to various pollutants, primarily particulate matter (PM). Exposure to environmental pollutants leads to upregulation of inflammatory markers and ciliary dysfunction at the cellular level. Mouse models suggest a role for epithelial barrier dysfunction contributing to inflammatory changes after pollutant exposure. Clinical studies support the role of pollutants contributing to disease severity in certain populations, but the role in CRS incidence or prevalence is less clear. Research is limited by the retrospective nature of most studies. This review focuses on recent advancements in our understanding of the impact of environmental pollutants in CRS, limitations of the available data, and potential opportunities for future studies.