T. Soumagne, AP-HP Nord-Université Paris Cité, Paris, France,
G. Garcia, J. Frija, C. Chenivesse, T. Perez, L. Plantier, et al.

J Allergy Clin Immunol Pract 2025

BACKGROUND: Dysfunctional breathing (DB) is common in severe asthma and is associated with poor asthma control. Diagnosing DB remains challenging due to the lack of gold standard.
OBJECTIVE: To investigate the characteristics of patients with severe asthma identified with DB using two distinct diagnostic modalities: the Nijmegen questionnaire (NQ) combined with the hyperventilation provocation test (HVPT), and cardiopulmonary exercise testing (CPET).
METHODS: Patients with severe asthma were prospectively recruited from three asthma expert centers. The diagnosis of DB using NQ-HVPT was confirmed by a panel of four chest physicians based on the results of the NQ and HVPT. CPET-based diagnosis was performed independently by two blinded physiologists, with erratic breathing patterns evaluated by visual inspection and objective criteria.
RESULTS: Among 138 patients with severe asthma, 44% were diagnosed with DB using NQ-HVPT. These patients were predominantly female, had poorer asthma control, lower quality of life and more comorbidities such as depression. Similar findings were noted when DB was defined by a NQ>23. The NQ was independently linked to anxiety, depression and quality of life regardless of DB diagnosis. Using CPET, 45% of patients were diagnosed with DB, but agreement between NQ-HVPT and CPET for DB diagnosis was poor (kappa=0.16). Patients diagnosed via CPET showed less impaired lung function and higher PaO2, possibly indicating a DB pattern more consistent with typical DB presentation.
CONCLUSION: The diagnostic agreement between NQ/HVPT and CPET is poor and both modalities may identify different DB patterns. The combination of NQ et HVPT seems to reflect the global burden of asthma rather than DB. CPET may be a more reliable tool for diagnosing DB, but further studies are needed to confirm its role.