Abstract Rationale Patients eligible for lung cancer screening are at risk for structural lung abnormalities including emphysema and airway wall thickening. Low-attenuation area (LAA) defined by density -950HU is a widely accepted measure of emphysema by chest CT. Th2 inflammation has been linked to airway remodeling, airway wall thickening, promotion of alveolar destruction and emphysema. Methods 305 participants enrolled in initial Lung Cancer Screening (LCS) consented to study. Electronic medical record (EMR) data and pre-bronchodilator (pre-BD) spirometry were collected along with CT imaging data (quantitative image analysis: AVIEW COPD, Coreline). Patients had blood eosinophil counts (BEC) drawn and Fractional Excretion of nitric oxide (FeNO) performed at their initial visit. Pearson correlation was performed to assess correlations between continuous variables of BEC and FeNO with % Emphysema (%LAA-950) and airway wall thickness (AWT-Pi10). This work was supported by grants from AstraZeneca and the Temple Lung Center Results 305 participants enrolled in LCS study had complete QCT data. Median age was 63 IQR 10, 182 females, 123 males, 187 active smokers. Median (IQR) for percent emphysema (%LAA-950), AWT-Pi10, PBE and FeNO was 1.7 (4.6), 4.06 (1.25), 140 (150), 10 (11). 143 (46.8 %) participants had BEC ≥150 and 53 (17.4 %) had BEC ≥ 300uL. 59 participants had FeNo ≥ 20ppb. Pearson correlation performed between BEC and %LAA-950 was ρ = +0.01, p = 0.806. BEC and AWT-Pi10 was ρ = +0.04, p = 0.441. FeNO and %LAA-950 was ρ = +0.12, p = 0.037. FeNO and AWT-Pi10 was ρ = -0.07, p = 0.247. In a cohort of only active smokers, Pearson correlation performed between BEC and %LAA-950 was ρ = +0.04, p = 0.558. BEC and AWT-Pi10 was ρ = +0.03, p = 0.711. FeNO and %LAA-950 was ρ = +0.1, p = 0.024. FeNO and AWT-Pi10 was ρ = -0.11, p = 0.132 Conclusion Results from the Temple Healthy Chest Initiative observational cohort showed a weak but statistically significant association between FeNO and quantitative emphysema (%LAA at -950HU). This correlation was strongest in the cohort of actively smoking participants. Further studies are needed to refine this relationship. This abstract is funded by: AstraZeneca
Dachert et al. (Fri,) studied this question.