Roseliane de Souza Araújo Alves, Flávia de Almeida Filardo Vianna, Carlos Alberto de Castro Pereira
Objective: To characterize clinical phenotypes of severe asthma. Methods: A total of 111 patients were retrospectively evaluated at a
specialized outpatient clinic. A systematic protocol for patient evaluation and follow-up was applied. Treatment compliance and control
of the disease at the end of follow-up were defined by clinical and functional data. Patients who did not meet asthma control criteria
after six months despite compliance with treatment and correct use of medication were characterized as treatment-resistant. Phenotypes
were determined by factorial analysis and compared using various tests. Results: At the end of follow-up, 88 patients were considered
treatment compliant and 23 were considered noncompliant. Factorial analysis of the compliant patients identified four phenotypes:
phenotype 1 (28 patients) comprised patients who were treatment-resistant, more often presenting nocturnal symptoms and exacerbations,
as well as more often using rescue bronchodilators; phenotype 2 (48 patients) comprised patients with persistent airflow limitation, lower
ratios of forced expiratory volume in one second/forced vital capacity at baseline, more advanced age and longer duration of symptoms;
phenotype 3 (42 patients) comprised patients with allergic rhinosinusitis who were nonsmokers and presented predominantly reversible
airflow obstruction; and phenotype 4 (15 patients) comprised cases with a history of aspirin intolerance to acetylsalicylic acid associated
with near-fatal asthma. Conclusions: A significant number of patients with severe asthma are noncompliant with treatment. Although many
patients with severe asthma have persistent airflow obstruction, the most relevant clinical phenotype comprises patients who are resistant
to the typical treatment.
Keywords: Asthma; Asthma/prevention & control; Asthma/treatment.