Clinical characteristics and burden of illness among adolescent and adult patients with severe asthma by asthma control: the IDEAL study.

Objectives: Severe asthma (SA) can be uncontrolled despite guideline-directed treatment. We described SA characteristics and identified factors associated with uncontrolled disease and frequent exacerbations.

Methods: analysis of the observational IDEAL study (201722/NCT02293265) included patients with SA aged ≥12 years receiving high-dose inhaled corticosteroids plus additional controller(s) for ≥12 months. Uncontrolled SA was defined by Asthma Control Questionnaire (ACQ)-5 scores ≥1.5 or ≥1 exacerbations (prior year), and further stratified by exacerbation frequency (no/infrequent [0-1] vs frequent [≥2]; prior year); associated factors were determined using multivariate logistic regression.

Results: Of 670 patients with SA, 540 (81%) were uncontrolled (ACQ-5 scores ≥1.5: 80%; ≥1 exacerbations [prior year]: 71%). Uncontrolled patients had lower lung function and worse health-related quality of life (HRQoL) than controlled patients; 197/540 (37%) experienced frequent exacerbations (prior year). Worse St George's Respiratory Questionnaire (SGRQ) total score, comorbid sinusitis, or eczema were significantly associated with uncontrolled SA; younger age, never smoker status, exacerbation requiring hospitalization (previous year), worse SGRQ symptom score, comorbid nasal polyps, COPD, or osteoporosis were significantly associated with uncontrolled SA with frequent exacerbations.

Conclusions: In IDEAL, one-fifth of patients with SA were controlled, based on symptoms. Uncontrolled, exacerbating SA was associated with specific comorbidities, frequent exacerbations, a lower lung function, and compromised HRQoL, although inference from this analysis is limited by the selective cross-sectional nature of the cohort. Nonetheless, these data highlight the need for more effective precision treatments in this population.