Monosensitization vs Polysensitization in Severe Asthma: Implications for Disease Severity

The impact of sensitization on asthma outcomes in adults is still being discussed. This study aims to describe the sensitization profiles and allergic comorbidities of patients with severe asthma, and to analyze their association with asthma severity.

This retrospective study included adult patients, evaluated at the Severe Asthma Clinic of Bichat University Hospital (Paris, France) during a 1-day hospital stay between May 2022 and January 2024. Sensitization, defined by a positive skin prick test and/or allergen-specific IgE levels greater than 0.10 kUA/L, was analysed alongside allergic comorbidities. The ASSESS score was used to grade asthma severity.

Of the 201 patients included, 142 (70.6%) exhibited at least one sensitization to an aeroallergen, of whom 38 (26.8%) were monosensitized, and 104 (73.2%) were polysensitized. Compared to polysensitized patients, monosensitized patients were older at diagnosis (years: 30.6 ± 20.1 vs 21.7 ± 17.6, p = 0.01), had a higher ASSESS score (median (Q1; Q3); 13 (11; 15) vs 11 (9; 14), p = 0.02), a lower pre-bronchodilator forced expiratory volume in 1 second (%pred: 70.3 ± 23.2 vs 79.3 ± 21.8, p = 0.03), and experienced a greater burden of exacerbations (p = 0.03). There were significantly more polysensitized patients with at least three allergic comorbidities, but the number of allergic comorbidities did not correlate with asthma severity.

Monosensitized patients exhibited more severe disease and greater airway obstruction compared to polysensitized individuals. These findings suggest that allergies, especially in cases of late-onset asthma, may not be a significant determinant of asthma severity in adults.