Evaluation of the concordance of asthma remission definitions according to international guidelines in a cohort of patients treated with monoclonal antibodies for severe asthma

Background The availability of biological therapies has helped achieve clinical remission (CR) in patients with severe asthma (SA). Scientific societies issued different definitions of remission, with the common denominator of the suspension of systemic corticosteroids for at least 1 year. Additional criteria are associated with symptoms, stability of pulmonary function, disease exacerbations, ACT ≥20 or ≥23, and ACQ ≤1.5. We evaluated the agreement among criteria adopted in Italy, Spain, Germany, Japan. Method An observational prospective, single-center study was carried out: 65 patients with SA treated for 12 or 24 months with omalizumab, mepolizumab, benralizumab or dupilumab were recruited. Data on exacerbations, need of systemic corticosteroids, asthma symptoms, ACT and ACQ, pulmonary function at baseline and 12 and 24 months were collected. Differences of qualitative variables were assessed with the Chi-squared or Fisher’s exact test. Cohen’s Kappa coefficients were calculated to assess agreement between definitions of remission. The statistical significance threshold was set at P < 0.05. Data analysis was carried out using STATA version 17. Results 28 (43.1%) patients at 12 months and 27 (47.4%) at 24 months did not meet any criteria for CR, whereas 34 (52.3%) at 12 months and 28 (49.1%) at 24 months met at least one definition of complete CR. The agreement among the selected guidelines was substantial, with an overall Fleiss K of 0.7971 (P < 0.0001). Chronic rhinosinusitis with nasal polyps was more prevalent in patients who achieved CR, whereas gastro-esophageal reflux disease was more prevalent in patients who did not. Conclusion Consistently with other studies only 52.3% at 12 months and 49.1% at 24 months achieved complete CR. The agreement of CR is substantial. The main limitations of the study are its monocentric nature and the poor sample size, whereas its main strengths were the evaluation both at 12 and 24 months and the adoption of four different definitions. Nonetheless, a worldwide definition could enhance the standardization of CR.