Air Pollution Exposure Found to Exacerbate Severity of Chronic Rhinosinusitis With Nasal Polyps

Exposure to air pollution may significantly increase disease severity in patients with chronic rhinosinusitis (CRS) with nasal polyps, according to study findings published in The Laryngoscope.

In examining potential contributors to the pathophysiology of CRS, air pollution has been identified across numerous studies to be an important environmental risk factor. Although patients with CRS with nasal polyps (CRSwNP) generally have more severe symptoms and higher recurrence rates vs those with CRS without NP, researchers noted that studies investigating the adverse effects of air pollution on this patient population remain limited.

They conducted a retrospective cohort study of patient data derived from monitoring sites in Beijing, China to assess individual exposure to 5 types of air pollution:

• Particulate matter (PM) 2.5 (PM_2.5) and PM 10 (PM₁₀)
• Sulfur dioxide (SO₂)
• Nitrogen dioxide (NO₂)
• Carbon monoxide (CO)
• Ozone (O₃)

“China, which has the largest number of patients with CRS worldwide, has experienced serious air pollution problems in recent years,” said researchers. “However, no study has focused on the association for air pollution and CRSwNP in the Chinese population.”

Participants with CRSwNP (n = 282; mean age, 44.7 years; 65.60% male) were assessed for several outcome measures, including the Lund-Mackay (L-M) score, Lund-Kennedy (L-K) score, visual analogue scale (VAS) score, and nasal patency/airflow resistance to analyze correlations with air pollution and compare groups with different exposure types.

Researchers also examined potential air pollution risk factors of the endotype of eosinophilic CRSwNP (ECRSwNP) via multivariable-adjusted binary logistic regression.

Among those with CRSwNP, the individual average 30 day concentration of PM_2.5 was 69.93 μg/m³, which exceeded the health criterion of Chinese Ambient Air Quality Standards. After assessing the 30-day average concentration of air pollution, researchers said that short-term exposures to PM_2.5/10, SO₂, CO, NO₂, and O₃ were weak but significantly associated with increased L-M scores (P < .05).

“The L-M scores of the group of the highest PM_2.5 (≥ 150 μg/m³) exposure were significantly higher than those of the control group.”

Moreover, short-term exposures to PM₁₀, CO, and NO₂ were correlated with increased VAS headache/facial pain scores (P < .01). Regarding the CRSwNP cellular endotype, each increased unit of the average concentration of PM_2.5 was associated with a 1.047-fold (95% CI, 1.005-1.091; P = .0293) increas ed risk of the endotype of ECRSwNP.

In concluding, researchers said that additional multi-center studies with large sample sizes are warranted to further elucidate the role of environmental exposures in CRS pathophysiology and patient outcomes.

“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.”

Reference

Yang X, Shen S, Deng Y, Wang C, and Zhang L. Air pollution exposure affects severity and cellular endotype of chronic rhinosinusitis with nasal polyps. Laryngoscope. Published online December 6, 2021. doi:10.1002/lary.29974