31 Nasal Nitric Oxide and Nasal Polyposis as Determinants of Asthma Control

BACKGROUND: The relationship between asthma control, its comorbidities and noninvasive markers of airway inflammation has been investigated with controversial results. The aim of this study was to analyze the relationship between level of asthma control (evaluated by ACT and ACQ questionnaires), its main comorbidities (rhinitis, chronic rhinosinusitis - CRS, obesity), exhaled nitric oxide (FENO) and nasal nitric oxide (nNO). METHODS: Forty-one consecutive asthmatic patients (mean age: 50 years, range: 21–80; 21 females; 2 smokers) were enrolled into the study. All patients were investigated to assess diagnosis of rhinitis, CRS (with or without nasal polyps) and obesity (by measuring the BMI). All patients underwent skin prick tests for a panel of common inhalant allergens, spirometry, FENO and nNO, and completed ACT and ACQ questionnaires. An univariate analysis was performed to identify determinants of asthma control (defined by means of ACT and ACQ values). RESULTS: Twenty-seven (65.9%) patients had ACQ values indicating asthma control (ACQ ≤1), while, according to ACT, only 14.6% of patients were completely controlled (ACT = 25), 48.8% partially controlled (20≥ ACT <25) and 36.6% uncontrolled (ACT <20). ACT and ACQ values were negatively correlated with nNO levels (R(2) = −0.175 and R(2) = 0.013 respectively). The univariate analysis showed that the the only significant determinants of lack of asthma control were nNO and the diagnosis of CRS with nasal polyps (P = 0.020 and 0.018 respectively). CONCLUSIONS: Nasal nitric oxide was the only biomarker, amongst those evaluated, which was correlated to asthma control. This finding suggests that nNO may reflect particular aspects of airway inflammation which may be more strictly correlated with asthma, underlying the importance of CRS with nasal polyps in loosing asthma control.