Exhaled nitric oxide levels correlate with measures of disease control in asthma

J Allergy Clin Immunol. 2000 Oct;106(4):645-50. doi: 10.1067/mai.2000.109618.


Background: Asthma guidelines emphasize maintaining disease control. However, objective measures of asthma disease control are lacking.

Objective: We sought to examine the relationship between exhaled nitric oxide (NO) levels and measures of asthma disease control versus asthma disease severity.

Methods: We performed a cross-sectional study of 100 patients (age range, 7-80 years) with asthma. We administered a questionnaire to identify characteristics of asthma, performed spirometric testing before and after administration of a bronchodilator, and measured exhaled NO levels in all participants.

Results: Exhaled NO was significantly correlated with the following markers of asthma disease control: asthma symptoms within the past 2 weeks (P =.02), dyspnea score (P =. 02), daily use of rescue medications (P =.01), and reversibility of airflow obstruction (P =.02). Exhaled NO levels were not correlated with the following markers of asthma disease severity: history of respiratory failure (P =.20), health care use (P =.08), fixed airflow obstruction (P =.91), or a validated asthma severity score (P =.19). Markers with relevance to both disease control and severity showed either a weak correlation (FEV(1) and FEV(1) percent predicted) or no correlation (controller drug use) with exhaled NO.

Conclusion: We conclude that exhaled NO levels are correlated predominantly with markers of asthma control rather than asthma severity. Monitoring of exhaled NO may be useful in outpatient asthma management.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Asthma / metabolism*
  • Asthma / prevention & control*
  • Child
  • Cross-Sectional Studies
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nitric Oxide / metabolism
  • Nitric Oxide / physiology*
  • Respiration
  • Severity of Illness Index


  • Nitric Oxide