Abstract
Although interest in biomarkers in the nitrate–nitrite–NO pathway has recently increased, associations between nitrite (NO2−) and nitrate (NO3−), and asthma, allergic sensitisation and rhinitis remain unclear.
The study aimed to evaluate the associations between NO2−/NO3− and exhaled fraction of nitric oxide (FeNO) levels with asthma, allergic sensitisation and rhinitis.
Plasma and exhaled breath condensate (EBC) NO2−/NO3− and FeNO levels were measured in 523 adults of the French Epidemiological study on Genetics and Environment of Asthma. Allergic sensitisation was defined by a positive skin prick test for at least one aeroallergen. Subjects were classified as non-sensitised, sensitised and as having allergic rhinitis.
Plasma NO2−/NO3− level was unrelated to any disease phenotypes. EBC NO2−/NO3− level was unrelated to any asthma phenotypes. EBC NO2−/NO3− and FeNO levels were correlated in sensitised subjects only (r=0.21±0.10, p=0.01). EBC NO2−/NO3− and FeNO levels were higher in sensitised than in non-sensitised subjects (adjusted geometric mean (95% CI): 2.36 (1.96–2.84) versus 1.72 (1.38–2.14) μmol per mg proteins, p=0.008; and 18.3 (16.7–20.0) versus 14.8 (13.3–16.5) ppb, p=0.0006, respectively), with gradual relationships from sensitised subjects to those with allergic rhinitis (p<0.0001).
Results suggest that EBC NO2−/NO3− and FeNO levels may be considered as biological markers of intensity of allergic sensitisation and rhinitis.
Abstract
The EGEA study: exhaled nitrate/nitrite/NO levels may be considered markers for intensity of allergy and rhinitis http://ow.ly/uKbxh
Footnotes
This article has supplementary material available from erj.ersjournals.com
Support statement: Research funded in part by PHRC-Paris, PHRC-Grenoble, ANR 05-SEST-020-02/05-9-97, ANR-06-CEBS, ANR-CES-2009, Region Nord Pas-de-Calais, Merck Sharp and Dohme (MSD), and the GA2LEN project, Global Allergy and Asthma European Network.
Conflict of interest: Disclosures can be found alongside the online version of this article at erj.ersjournals.com
- Received November 19, 2013.
- Accepted February 28, 2014.
- ©ERS 2014