RESUMO
BACKGROUND: Sixty-five percent of people with severe asthma and a fractional exhaled nitric oxide (Feno) greater than or equal to 45 parts per billion (ppb) are nonadherent to inhaled corticosteroids (ICSs). Digital devices recording both time of use and inhaler technique identify nonadherence and ICS responsiveness but are not widely available. As the NEXThaler dose counter activates only at an inspiratory flow rate of 35 L/min, this may provide an alternative to identifying ICS responsiveness. OBJECTIVE: To assess ICS adherence and responsiveness in severe asthma using beclometasone/formoterol (200/6 µg) NEXThaler (BFN) dose-counting. METHODS: Patients with severe asthma with a Feno greater than or equal to 45 ppb were invited to use BFN in place of their usual ICS/long-acting ß2-agonist. Feno, 6-item Asthma Control Questionnaire score, lung function, and blood eosinophil count were monitored for 3 months. A log10ΔFeno of greater than or equal to 0.24 was used to define Feno suppression as the primary marker of ICS responsiveness at day 28. RESULTS: Twenty-seven of 48 (56%) patients demonstrated significant Feno suppression at month 1 (median pre-114, post-48 ppb, P < .001). A small but significant reduction occurred in Feno nonsuppressors. The 6-item Asthma Control Questionnaire score fell a median 1.2 units in Feno suppressors (P < .001) and 0.5 units in nonsuppressors (P = .025). These effects were sustained until month 3 in Feno suppressors, with a significant improvement in FEV1 and blood eosinophils. Sixty-seven percent (18 of 27) of those with baseline ICS/long-acting ß2-agonist prescription refills of 80% or more were Feno suppressors, suggesting prior nonadherence despite adequate prescription collection. Seventy-nine percent of Feno suppressors did not require biologics within mean 11.4 months from initial dose counting. CONCLUSIONS: BFN dose-counting identifies ICS responsiveness in severe asthma with the implication that these patients may not need to progress to biological therapies.
RESUMO
BACKGROUND: Nonadherence in difficult-to-control asthma can be identified using 7-day FeNO suppression testing where patients take additional fluticasone via Diskus with an Inhaler Compliance Assessment (INCA) acoustic monitoring device attached, and self-measure FeNO at home. However, this is inconvenient for patients attending a tertiary center and limited by FeNO meter availability. It is not known if this approach alters clinical outcomes. OBJECTIVES: To examine patient acceptability and the effectiveness of replacing usual combination inhaled corticosteroid (ICS)/long-acting ß2-agonist (LABA) therapy with a fluticasone/salmeterol Diskus 500+INCA for 28 days as the initial intervention, compared with the 7-day FeNO suppression test, and to explore clinical outcomes after INCA monitoring. METHODS: A service evaluation of FeNO suppression testing was undertaken in clinical practice. RESULTS: Twenty-one of 23 subjects offered replacement of their usual ICS/LABA with fluticasone/salmeterol+INCA as the initial intervention accepted and completed 28 days of monitoring. Fourteen (66.6%) patients reduced their FeNO by >42% (FeNO suppressors), accompanied by improvements in forced expiratory volume in 1 second, Asthma Control Questionnaire, and blood eosinophils, similar to the 7-day test (n = 74). Twenty-two of 62 (35.5%) FeNO suppressors progressed to biological therapy, compared with 24 of 33 (72.7%) nonsuppressors (P = .0006). FeNO suppressors taking maintenance prednisolone (n = 13) who did not receive biological therapy reduced the median baseline dose from 10 to 3 mg, with further reductions limited by adrenal suppression. CONCLUSION: Replacing existing inhaled therapy with fluticasone/salmeterol+INCA for 28 days is acceptable to the majority of people with difficult-to-control asthma and identifies prior medication nonadherence. INCA monitoring coupled with clinical support potentially improves patient adherence and asthma control, preventing unnecessary progression to biological therapy.
