Relationship between air pollution exposure and the progression of idiopathic pulmonary fibrosis in Madrid: Chronic respiratory failure, hospitalizations, and mortality. A retrospective study

The role of environmental pollution in the development of pulmonary exacerbations in cystic fibrosis: a narrative review

Cystic fibrosis is the most common autosomal recessive disease in the Caucasian race. Its course is chronic and progressive, with pulmonary involvement being associated with greater morbidity and mortality. One of the factors most related to worse prognosis in these patients is respiratory exacerbations. Although limited, there is evidence demonstrating that increased exposure to environmental pollution, both acute and chronic, is associated with an increase in these exacerbations. It is crucial to fully understand this relationship in order to attempt to improve the respiratory health of these patients. That is why the available evidence is reviewed and measures are established to reduce exposure to pollutants.

The impact of air pollution on interstitial lung disease: a systematic review and meta-analysis

Introduction

There is a growing body of evidence suggesting a causal relationship between interstitial lung disease (ILD) and air pollution, both for the development of the disease, and driving disease progression. We aim to provide a comprehensive literature review of the association between air pollution, and ILD, including idiopathic pulmonary fibrosis (IPF).

Methods

We systematically searched from six online database. Two independent authors (DL and CF) selected studies and critically appraised the risk of bias using the Newcastle-Ottawa Scale (NOS). Findings are presented through a narrative synthesis and meta-analysis. Meta-analyses were performed exclusively when there was a minimum of three studies examining identical pollutant-health outcome pairs, all evaluating equivalent increments in pollutant concentration, using a random effects model.

Results

24 observational studies conducted in 13 countries or regions were identified. Pollutants under investigation encompassed ozone (O3), nitrogen dioxide (NO2), Particulate matter with diameters of 10 micrometers or less (PM10) and 2.5 micrometers or less (PM2.5), sulfur dioxide (SO2), carbon monoxide (CO), nitric oxide (NO) and nitrogen oxides (NOx). We conducted meta-analyses to assess the estimated Risk Ratios (RRs) for acute exacerbations (AE)-IPF in relation to exposure to every 10 μg/m3 increment in air pollutant concentrations, including O3, NO2, PM10, and PM2.5. The meta-analysis revealed a significant association between the increased risk of AE-IPF in PM2.5, yielding RR 1.94 (95% CI 1.30-2.90; p = 0.001). Findings across all the included studies suggest that increased exposure to air pollutants may be linked to a range of health issues in individuals with ILDs.

Conclusion

A scarcity of available studies on the air pollutants and ILD relationship underscores the imperative for further comprehensive research in this domain. The available data suggest that reducing levels of PM2.5 in the atmosphere could potentially reduce AE frequency and severity in ILD patients.

Air pollution exposure and its effects on idiopathic pulmonary fibrosis: clinical worsening, lung function decline, and radiological deterioration

Introduction

Major urban pollutants have a considerable influence on the natural history of lung disease. However, this effect is not well known in idiopathic pulmonary fibrosis (IPF).

Aim

This study aimed to investigate the effects of air pollution on clinical worsening, lung function, and radiological deterioration in patients with IPF.

Methods

This exploratory retrospective cohort study included 69 patients with IPF, monitored from 2011 to 2020. Data on air pollution levels, including carbon monoxide (CO), nitrogen dioxide (NO2), particulate matter ≤ 2.5 μM (PM2.5), ozone (O3), and nitrogen oxides (NOx), were collected from the nearest air quality monitoring stations (<3.5 km from the patients' homes). Patient outcomes such as clinical worsening, lung function decline, and radiological deterioration were assessed over various exposure periods (1, 3, 6, 12, and 36 months). The statistical analyses were adjusted for various factors, including age, sex, smoking status, and treatment.

Results

There was an association between higher O3 levels and an increased likelihood of clinical worsening over 6 and 36 months of exposure (odds ratio [OR] and 95% confidence interval [CI] = 1.16 [1.01-1.33] and OR and 95% CI = 1.80 [1.07-3.01], respectively). Increased CO levels were linked to lung function decline over 12-month exposure periods (OR and 95% CI 1.63 = [1.01-2.63]). Lastly, radiological deterioration was significantly associated with higher CO, NO2, and NOx levels over 6-month exposure periods (OR and 95% CI = 2.14 [1.33-3.44], OR and 95% CI = 1.76 [1.15-2.66] and OR and 95% CI = 1.16 [1.03-1.3], respectively).

Conclusion

This study suggests that air pollution, specifically O3, CO, NO2, and NOx, could affect clinical worsening, lung function, and radiological outcomes in patients with IPF. These findings highlight the potential role of air pollution in the progression of IPF, emphasizing the need for further research and air quality control measures to mitigate its effects on respiratory health.

Where you live matters: Roadways, air pollution and lung function in patients with idiopathic pulmonary fibrosis

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