One practical importance with the NIOX value is the ability to identify patients with respiratory symptoms who will benefit from antiinflammatory treatment.
Steroid response can be expected in patients with an ongoing eosinophilic inflammation. The NIOX Value can be used for immediate and non-invasive identification of steroid responsiveness.
In patients with non-specific symptoms, a NIOX Value of >47 ppb is highly indicative of a subsequent corticosteroid response (Smith 2005) .
A high NIOX Value correctly identifies the responders better than spirometry (FEV1 bronchodilator response) or PEF variability. It helps to identify children who subsequently will achieve a greater improvement in asthma control days with an inhaled corticosteroid (Zeiger 2006) .
Patients with normal NIOX Values and no symptomatic response to anti-inflammatory treatment may not have any underlying inflammation. Other forms of therapy should therefore be considered. Discontinuing anti-inflammatory treatment may also be appropriate.
A baseline NIOX Value of >47 ppb correlates with a lung function improvement of > 12% following 4 weeks of inhaled corticosteroids.
A baseline NIOX Value of <47 ppb predicted no improvement in lungfunction with 4 weeks of inhaled corticosteroids (Smith 2005) .
Smith AD, Cowan JO, Brassett KP, Filsell S, McLachlan C, Monti- Sheehan G, Herbison GP, Taylor DR. Exhaled nitric oxide: a predictor of steroid response. Am J Respir Crit Care Med 2005;172:453-9.
Zeiger RS, Szefler SJ, Phillips BR, Schatz M, Martinez FD, Chinchilli VM, Lemanske RF Jr, Strunk RC, Larsen G, Spahn JD, Bacharier LB, Bloomberg GR, Guilbert TW, Heldt G, Morgan WJ, Moss MH, Sorkness CA, Taussig LM; CARE Network of the NHLBI. Response profiles to fluticasone and montelukast in mild-to-moderate persistent childhood asthma. J Allergy Clin Immunol. 2006 Jan;117(1):45-52.