Correlation between Nasal Symptoms and Nasal Nitric Oxide at Baseline and while Humming

Abstract

Background: Chronic rhinosinusitis (CRS) is important in asthma and chronic cough assessment. An accurate diagnosis of CRS based solely on symptoms and nasal endoscopy can be difficult. Sinus CT-imaging is usually recommended in patients with negative rhinoscopy. Nasal nitric oxide (nNO) levels obtained passively and while humming are decreased in sinusitis due to ostiomeatal complex blockage of paranasal sinus gas exchange by inflamed tissue. A nNO measurement is a potential point-of-care test (POCT) for CRS. The SinoNasal Outcome Test (SNOT-20) is a clinical tool to assess symptoms in CRS.Objective: To evaluate if nNO levels provided objective information about CRS that would correlate with individual elements in the SNOT-20 and 6 additional CRS related symptoms. To examine these 26 symptom parameters for related clusters, and test correlation of the clusters with nNO measurements.Methods: In 180 patients, basal and humming nNO level measurements, and 26 symptoms (SNOT-20 plus 6 added items) were collected. Hierarchical cluster analysis was applied to sort the data into clusters.Results: The 26 questions grouped into 5 different clusters. 2 clusters contained questions that were most disease specific for sinonasal diseases in patients referred for subspecialty asthma and chronic cough evaluation. We demonstrated that nNO levels during humming, and the ratio between humming and basal nNO, correlated best with clusters 2 and 4.Conclusion: Baseline and humming nNO measurements provide objective information about CRS. nNO measurements offers the potential of a POCT for objective assessment of CRS in patients presenting to a pulmonary clinic