Fractional exhaled nitric oxide and eosinophil count in induced sputum to guide the management of children with asthma: a cost-utility analysis

Introduction Previous evidence has shown that fractional exhaled nitric oxide (FeNO) and eosinophil count in induced sputum (EO) are cost-effective relative to standard of care in guiding the management of children with persistent asthma. There is some doubt as if there are differences between these two biomarkers in terms of costs and benefits. Clarifying this doubt would allow prioritization of the design of clinical practice guidelines. The study aimed to compare in terms of costs and benefits these biomarkers in patients with asthma between 4 and 18 years of age. Methods A Markov model was used to estimate the cost-utility of asthma management using FeNO and EO in patients between 4 and 18 years of age. Transition probabilities, cost and utilities were estimated from previously published local studies, while relative risks were obtained from the systematic review of published randomized clinical trials. The analysis was carried out from a societal perspective. Results The expected annual cost per patient with EO was US $1376 (CI 95% US $1376-US $1377) and for FeNO was US $1934 (CI 95% US $1333-US $1334), with a difference of US $42.3 between these strategies. The Quality-adjusted life years (QALYs) per person estimated with EO was 0.95 (CI 95% 0.951-0.952) and for FeNO was 0.94 (CI 95% 0.930-0.940), with a difference of 0.01 between these strategies. The NMB with EO was US $4902 (CI 95% 4900-4904) and for FeNO was US $4841 (CI 95% 4839-4843). The incremental cost-effectiveness ratio of EO was $3566 per QALY gained regarding FeNO. Conclusion Our study demonstrates that induced sputum-guided management is a strategy cost-effective over FeNO and standard asthma management in Colombia. This evidence should encourage the adoption of any of these techniques to objectively guide the management of children with asthma in routine clinical practice in low-resource settings.