Prevalence of the eosinophilic phenotype among severe asthma patients in Brazil: the BRAEOS study

J Bras Pneumol. 2022 Jul 8;48(3):e20210367. doi: 10.36416/1806-3756/e20210367. eCollection 2022.
[Article in English, Portuguese]

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.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Asthma* / diagnosis
  • Brazil / epidemiology
  • Cross-Sectional Studies
  • Eosinophils
  • Female
  • Humans
  • Leukocyte Count
  • Male
  • Phenotype
  • Prevalence