Novel Model Appears Effective at Predicting ECRSwNP

Asthma, blood eosinophil percentage (EOS%), posterior ethmoid (PE) value in Lund-Mackay (LM) score, and modified Lund-Kennedy (MLK) score were the factors that contributed to a novel model being able to predict eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP), according to study findings published in Ear, Nose & Throat Journal.

These results were seen among 110 study participants in this retrospective analysis who underwent endoscopic sinus surgery between March 2014 and March 2019 at San Luigi Gonzaga Hospital in Turin, Italy. Most of the 110 patients were classified as having ECRSwNP (65%), among whom 100% had bilateral occurrence of nasal polyps.

“A single predictive biomarker for ECRSwNP has not yet been identified,” the authors wrote. “The aim of this study is to compare the clinical characteristics of ECRSwNP and non-ECRSwNP to evaluate the preoperative risk of tissue eosinophilia of CRSwNP through a multiparametric statistical analysis.”

For this study, a diagnosis of ECRSwNP was based on the presence of at least 10 eosinophils per high-power field. The study had 3 aims: describe CRS clinical features and objective parameters, evaluate a possible association between higher blood eosinophilia and ECRSwNP, and calculate risk factors (prior sinus surgery, smoking status, gastroesophageal reflux disease [GERD], blood pressure, diabetes, asthma, allergic rhinitis, Sino-Nasal Outcome Test-22, LM scores, and MLK scores) associated with ECRSwNP.

Occurrence of allergies (40.0% vs 28.8%), asthma (50.7% vs 17.7%), mean eosinophilia of 1000/mcL (0.5% vs 0.2%), number of hypereosinophilia (76.9% vs 37.7%), hypertension (26.1% vs 22.2%), diabetes (3.1% vs 0.0%), GERD (21.5% vs 17.7%), and aspirin-exacerbated respiratory disease (12.3% vs 0.0%) were all higher in the study participants who had ECRSwNP vs those with non-ECRSwNP.

For the authors’ aim of finding a potential connection between higher blood eosinophilia and ECRSwNP occurrence, they evaluated several measures of EOS% using this equation: (1 – sensitivity) – (1 – specificity). They landed on an optimal EOS% value above 4.15%, which had 77% sensitivity and 62% specificity, and an optimal absolute eosinophil count above 0.365 x 10³/mcL, which had 55% sensitivity and 76% specificity.

The third aim involved univariate and multivariate logistic regression risk factor analyses. The univariate analysis showed that LM score, MLK score, anterior ethmoid sinus, PE sinus, and sphenoid sinus (all P < .001) were significantly associated with the probability of having ECRSwNP (based on P ≤ .05), and the multivariate logistic model showed just MLK score (P = .014) and PE sinus in the LM score (P = .047) had a significant association.

A final analysis, stepwise logistic regression, was used by the authors “to choose the multivariate model with the minimum number of the most significant predictive variables.” This produced the ECRSwNP predictive model that incorporated asthma, EOS%, PE sinus in the LM score, and MLK score.

“In our study, in both the univariate logistic regression analyses and the multivariate logistic relationship, we found a statistically significant correlation between the MLK value and tissue eosinophilia. In addition, in the new model proposed for preoperative assessment of tissue eosinophilia, the most significant marker is MLK and not the percentage value of blood eosinophils,” the authors wrote. “In conclusion, this study helps clarify which factors are most associated with ECRSwNP in order to assist in defining endotypes.”

Reference

Fadda GL, Galizia A, Galizia G, Castelnuovo P, Bignami M, Cavallo G. Multiparametric analysis of factors associated with eosinophilic chronic rhinosinusitis with nasal polyps. Ear Nose Throat J. 2022;101(6):NP256-NP262.doi:10.1177/0145561320960357