Exhaled nitric oxide and asthma control: a longitudinal study in unselected patients

Abstract

Controlled studies have shown that monitoring of the exhaled nitric oxide fraction (FeNO) improves asthma management. However, the studies seldom consider the full range of patients seen in clinical practise. In the present study, the ability of FeNO to reflect asthma control over time is investigated in a regular clinical setting, and meaningful FeNO cut-off points and changes are identified.Answers to the Asthma Control Questionnaire and FeNO were recorded at least once in 341 unselected asthma patients. The whole population and subgroups were considered, i.e. both inhaled corticosteroid (ICS)-naïve and low or high-to-medium (f or .500 mg beclomethasone dipropionate equivalents?day -1 ) ICS-dose groups.An FeNO decrease ,40% or increase ,30% precludes asthma control optimisation or deterioration, respectively (negative predictive value 79 and 82%, respectively). In the present study's low-dose group, a decrease .40% indicated asthma control optimisation (positive predictive value (PPV) 83%). In ICS-naïve patients, FeNO .35 ppb predicted asthma control improvement in response to ICS (PPV 68%). In most cases, forced expiratory volume in one second assessments were not useful.In conclusion, in a given patient, exhaled nitric oxide fraction was found to be significantly related to asthma control over time. The overall ability of exhaled nitric oxide fraction to reflect asthma control was reduced in patients using high doses of inhaled corticosteroids. Forced expiratory volume in one second had little additional value in assessing asthma control.

Comparison of Orally Exhaled Nitric Oxide in Allergic versus Nonallergic Rhinitis

“…33 Our observation of insignificant reduction in FeNO measurements after nasal steroids is in agreement with other reports that could not detect any decrease in airway inflammation. 34 The patients may have had a moderate-to-severe degree of rhinitis, which did not give enough response to ICSs. Another explanation is that no improvement in airway inflammation after nasal glucocorticoid in patients with comorbid asthma suggests a bidirectional link between upper and lower respiratory tract, because a majority of our patients with asthma were already under treatment with inhaled steroids.…”

The Clinical Utility of Fractional Exhaled Nitric Oxide (FeNO) in Asthma Management

“…Honkoop et al allocated 611 adults with asthma from primary care clinics to three treatment strategies: (1) aiming at ACQ score <1.50; (2) ACQ score <0.75; and (3) aiming at ACQ score <0. 75 and FeNO value <25 ppb. During the 12-month followup, treatment was adjusted every 3 months by using an online decision support tool.…”

“…Honkoop et al, in a cluster RCT, showed that medication costs over a year was lower for a treatment strategy that kept ACQ score <1.50, followed by keeping ACQ score <0. 75 and FeNO value <25 ppb, followed by keeping ACQ score <0.75 ($452, $456, $551; P ≤ 0.04). 128 Beerthuizen et al assessed the cost-effectiveness of web-based monthly monitoring and of 4-monthly monitoring of FeNO compared with standard care (followup evaluation of RCT in 272 children with asthma, aged 4-18 years, followed for 1 year).…”

“…Overall, the correlation was weak, and FeNO did not reliably differentiate patients who were well-controlled versus borderline controlled versus not wellcontrolled. [73][74][75][76][77] In a cross sectional study, a single measurement of FeNO had lower area under …”

Intérêt de la mesure de l’inflammation en clinique dans l’asthme

“…Cependant, l'étude longitudinale de Michils et al a rapporté que les changements individuels du taux de FE NO en fonction de l'ACQ représentent une aide pronostique. En effet, une diminution de 40 % du taux de FE NO chez un patient permettait de prédire une réduction du score d'ACQ et donc une amélioration du contrôle de l'asthme avec une valeur prédictive positive de 83 % et une valeur prédictive négative de 79 % [95] . En ce qui concerne les seuils permettant de prédire une perte de contrôle de l'asthme, Zacharasiewicz a rapporté qu'un taux de FE NO supérieur à 22 ppb chez des enfants traités par stéroïdes inhalés est associé à un risque six fois supérieur de perte de contrôle de l'asthme pendant la réduction du traitement par corticosté-roïdes [82] .…”