RESUMO Objetivo: Avaliar a prevalência dos fenótipos eosinofílico e alérgico da asma grave no Brasil e investigar as características clínicas dos pacientes com asma grave no país. Métodos: Estudo transversal com pacientes adultos com diagnóstico de asma grave atendidos em centros especializados no Brasil. O estudo foi realizado em 2019. Resultados: Foram incluídos no estudo 385 pacientes. Destes, 154 apresentavam contagem de eosinófilos no sangue > 300 células/mm3 e 231 apresentavam contagem de eosinófilos no sangue ≤ 300 células/mm3. A mediana da idade foi de 54,0 anos, e a maioria dos pacientes era do sexo feminino, com IMC de 29,0 kg/m2 e história de alergia (81,6%). A prevalência de pacientes com contagem de eosinófilos no sangue > 300 células/mm3 foi de 40,0% (IC95%: 35,1-44,9), e a daqueles com contagem de eosinófilos no sangue > 300 células/mm3 e história de alergia foi de 31,9% (IC95%: 27,3-36,6). A idade e o IMC apresentaram associações positivas com contagem de eosinófilos no sangue > 300 células/mm3 (OR = 0,97, p < 0,0001 e OR = 0,96, p = 0,0233, respectivamente), ao passo que o tempo decorrido desde o início dos sintomas de asma apresentou associação aumentada com contagem de eosinófilos no sangue > 300 células/mm3 (OR = 1,02, p = 0,0011). Conclusões: Este estudo possibilitou a caracterização da população de pacientes com asma grave no Brasil, mostrando a prevalência do fenótipo eosinofílico (em 40% da amostra). Nossos resultados revelam a relevância do fenótipo eosinofílico da asma grave em nível nacional, contribuindo para aumentar a eficácia no manejo da doença e na implantação de estratégias de saúde pública.

ABSTRACT Objective: To assess the prevalence of the eosinophilic and allergic phenotypes of severe asthma in Brazil, as well as to investigate the clinical characteristics of severe asthma patients in the country. Methods: This was a cross-sectional study of adult patients diagnosed with severe asthma and managed at specialized centers in Brazil. The study was conducted in 2019. Results: A total of 385 patients were included in the study. Of those, 154 had a blood eosinophil count > 300 cells/mm3 and 231 had a blood eosinophil count of ≤ 300 cells/mm3. The median age was 54.0 years, and most of the patients were female, with a BMI of 29.0 kg/m2 and a history of allergy (81.6%). The prevalence of patients with a blood eosinophil count > 300 cells/mm3 was 40.0% (95% CI: 35.1-44.9), and that of those with a blood eosinophil count > 300 cells/mm3 and a history of allergy was 31.9% (95% CI: 27.3-36.6). Age and BMI showed positive associations with a blood eosinophil count > 300 cells/mm3 (OR = 0.97, p < 0.0001; and OR = 0.96, p = 0.0233, respectively), whereas the time elapsed since the onset of asthma symptoms showed an increased association with a blood eosinophil count > 300 cells/mm3 (OR = 1.02, p = 0.0011). Conclusions: This study allowed us to characterize the population of severe asthma patients in Brazil, showing the prevalence of the eosinophilic phenotype (in 40% of the sample). Our results reveal the relevance of the eosinophilic phenotype of severe asthma at a national level, contributing to increased effectiveness in managing the disease and implementing public health strategies.

INTRODUCTION: Asthma affects approximately 10% of the world's population. Sensitization to allergens is an important risk factor, and exposure to allergens is associated with disease severity. METHODS: We performed skin tests to evaluate allergen sensitization to mites, cockroaches, cats, dogs, and molds in 73 asthmatic patients. Enzyme Linked Immunosorbent Assay was used to assay the mite and cockroach allergens found in dust from the bedding, hammocks, bedroom floors, living rooms, and kitchens of 29 patients and 14 controls. RESULTS: Fifty patients (68.5%) had positive skin test responses. There were positive responses to D. pteronyssinus (52.0%), B. tropicalis (53.4%), T. putrescentiae (15.0%), E. maynei (12.3%), L. destructor (8.2%), B. germanica (20.5%), P. americana (21.9%), Felis catus (10.9%), C. herbarium (2.7%), A. alternata (4.1%), and P. notatun (1.3%). The exposure to mite and cockroach allergens was similar in the patients and the controls. The Dermatophagoides pteronyssinus Group 1 levels were highest in the beds and hammocks. The Blattella germanica Group 1 levels were highest in the kitchens, living rooms and hammocks. DISCUSSION: The positive skin tests to mites, cockroaches and cats were consistent with previous studies. D pteronyssinus was the most prevalent home dust mite, and hammocks were a source of allergens. To improve asthma prophylaxis, it is important to determine its association with mite allergen exposure in hammocks.