FeNO Predicts Exacerbation Risk in Asthma & COPD

In a recent study, researchers from the Netherlands found that fractional exhaled nitric oxide (FeNO) testing, along with blood eosinophil counts, could serve as complementary biomarkers to help predict asthma and COPD exacerbation risk.

Key Findings from the NOVELTY Study

• Higher baseline eosinophil counts were associated with an increased risk of exacerbations in asthma.
• Elevated FeNO levels were linked to a lower overall risk of exacerbations in COPD.
• In asthma, higher FeNO levels were associated with greater odds of exacerbations treated only with oral corticosteroids.
• Higher FeNO levels were also linked to increased odds of oral corticosteroid-treated exacerbations in patients with asthma-COPD overlap.
• In asthma, elevated FeNO was associated with lower odds of exacerbations treated only with antibiotics.
• When both biomarkers were analyzed together, higher eosinophil counts and lower FeNO levels independently predicted exacerbation risk in COPD.

Reference
Muiser S, Miillerova H, Belton L, et al. Association of blood eosinophils and exhaled nitric oxide with exacerbations in patients with asthma, COPD and asthma+COPD: the NOVELTY study. Thorax. Published online April 21, 2026. doi:10.1136/thorax-2025-223646

Whether used on its own or alongside other diagnostic tests, FeNO testing with devices like the MGC Diagnostics Fenom Flo® provides valuable insights into airway inflammation and is recognized as a useful adjunct for respiratory assessment. This point-of-care device is compact, easy to move from room to room, and is the only device approved for a 6-second breath test. For fast, simple measurement of fractional exhaled nitric oxide, the Fenom Flo® helps clinicians make more informed decisions when evaluating and managing patients with asthma and COPD.