The Use of Portable Device for Measuring Nasal FeNO in Subjects with Allergic Rhinitis - A Single Center Study

Objective: This study aimed to demonstrate the accuracy of a portable device for measuring nasal and bronchial fractional exhaled nitric oxide (nFeNO and FeNO) as an alternative method to replace a high-cost multiple flow device in subjects with allergic rhinitis (AR) . Methods: It was a descriptive and comparative study. The healthy subjects (control group), subjects with AR (AR group) and those with AR and asthma (AR-A group) were enrolled in this study. They underwent nasal and bronchial FeNO measurements by both fixed flow NObreath ® connected to nasal mask (for nFeNO) and without mask (for FeNO) and multiple flows HypAir FeNO ® . Results: There were 153 subjects recruited during the study period, including 63 healthy subjects and 90 subjects with AR and AR-A. There were no statistically significant differences in anthropometric characteristics between study groups. The concentrations of nasal FeNO and bronchial FeNO measured by a portable device in subjects with AR were higher than in healthy subjects: 76.0 ± 50.7 ppb vs 36.0 ± 28.1 ppb ( P < 0.01), and 32.3 ± 15.4 ppb vs 9.2 ± 5.6 ppb ( P < 0.001). There was a weak correlation between nasal FeNO measured by portable devices and multiple flow devices. Conclusions: The portable device is useful in measuring nasal FeNO in subjects with AR. The advantages of a low-cost and accurate portable device may help it be used in primary care in the management of subjects with allergic rhinitis and asthma