Relationship between fractional exhaled nitric oxide, asthma control test, and spirometry measurement in individuals with asthma receiving treatment

To evaluate the relationship between fractional exhaled nitric oxide (FeNO), asthma control test (ACT), and spirometry measurements in individuals with asthma receiving treatment, a cross-sectional study was conducted involving 47 diagnosed asthmatic patients. FeNO levels were measured using Eversens Evernoa FeNO, ACT scores were recorded, and spirometry (pre- and post-bronchodilator) was conducted. Correlations between these parameters were analyzed using Pearson's correlation and t-tests. The study found no statistically significant correlation between FeNO and spirometry parameters [forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and FEV1/FVC] or ACT scores. While FeNO was higher in individuals without a family history of asthma and nonsmokers, these differences were not statistically significant. Additionally, spirometry parameters showed significant improvement after bronchodilator use, but FeNO did not strongly predict lung function improvement. The findings suggest that while FeNO is useful as an indicator of airway inflammation, it may not consistently correlate with functional lung measurements or asthma control as assessed by spirometry and ACT. This highlights the need for a multidimensional approach to asthma management that combines these tools for more comprehensive disease assessment.