Supporting the diagnosis of non-specific respiratory symptoms in primary care: The role of exhaled nitric oxide measurement and spirometry

Abstract

Aims: To assess whether exhaled nitric oxide (FENO) measurements improve management and clinician confidence in patients presenting with non-specific respiratory symptoms. Methods: This observational study was based in a large primary care practice (15,500 patients, 14 GPs). Patients had non-specific respiratory symptoms for at least six weeks. FENO and spirometry measurements were performed at initial assessment. An algorithm was employed to assist interpretation of FENO and spirometry results. GPs evaluated the diagnostic contribution of FENO and spirometry at 3-month follow-up. Results: In 48/51 (94%) of cases FENO was considered significant in formulating a diagnosis. Spirometry was deemed helpful in 27/51 (54%). Conclusion: FENO measurements improved diagnostic confidence when assessing non-specific respiratory symptoms. This may be because, in contrast to spirometry, both low and high FENO values have clinical significance. Trial registration: Australian Clinical Trials Registry ACTRN012605000354684. © 2008 General Practice Airways Group. All rights reserved.