Blood eosinophilia and a higher ethmoid sinus/maxillary sinus score ratio predict new-onset asthma in patients with chronic rhinosinusitis with nasal polyps.

Backgroud: Presently, the impact of Chronic rhinosinusitis with nasal polyps (CRSwNP) on asthma onset is unknown.
Aims: To evaluate the role of CRSwNP in asthma onset.
Materials and Methods: A total of 3107 CRSwNP patients were retrospectively screened from 1 January 2018, to 31 May 2021; 624 patients were enrolled. Clinical data regarding nasal symptoms, Lund-Mackay scores, blood eosinophil percentage, and onset of asthma were analyzed. Patients were divided into different groups according to past history of nasal polyps, Lund-Mackay score, and the extent of blood eosinophilia. Asthma-free rates between these subgroups were analyzed by Kaplan-Meier curves and Cox regression models.
Results: The prevalence of asthma was 10.90% in patients with CRSwNP, and new-onset asthma occurred in 3.14% of these patients. Higher Lund-Mackay scores for ethmoid sinus and maxillary sinus (E/M) and blood eosinophil percentages were two independent risk factors for new-onset asthma, with hazard ratios of 1.267 (95%CI, 1.155-1.390) and 1.224 (95%CI, 1.054-1.422), respectively. CRSwNP patients with an E/M ratio > 2.33 or a blood Eos percentage > 5.5% were at risk for asthma onset.
Conclusions and Significance: Blood eosinophilia and a higher E/M score ratio were associated with new-onset asthma in patients with CRSwNP.