FeNO in a healthy population: normal ranges and contributing factors

Fractional exhaled nitric oxide (FeNO) is a type 2 inflammation marker used in the management of asthma. Current standards focus on thresholds to designate the presence and degree of local inflammation. However, epidemiological knowledge of FeNO values in general populations is needed to better understand the normal ranges and contributing factors ([Abb. 1]).

Abb. 1  

In this analysis 3110 healthy probands without any history of respiratory diseases, atopy, inhaled medication use, current smoking, obstructive lung function and/or bronchial reversibility, aged 6-82 years with valid FeNO testing were included from the Austrian LEAD study, a single-centred, observational, longitudinal, general population cohort. The mean values and associations of FeNO with anthropometrics, non-respiratory diseases, history including symptoms, exposures, inflammatory parameters, allergy, and lung function were assessed.

FeNO levels were affected as seen in the stratification and stepwise linear regression analyses:

Our data elucidate normal FeNO values of a large, respiratory healthy population, which are lower in adolescents and adult females and highest in adult men. In general, FeNO is affected by blood eosinophils, lung function and by age and height in adults.

Publication History

Article published online:
09 March 2023