The Characterization and Comparison of Eosinophilic and Non-eosinophilic Phenotypes of Severe Asthma

This cross-sectional study design is the first step to better understand and assess the presence of eosinophilic and non-eosinophilic asthma phenotypes using known constructs of severe asthma epidemiology. Firstly, most likely non-eosinophilic asthma patients will be identified followed by discerning eosinophilic asthma patients with most likely versus likely degrees of confidence. The characteristics of eosinophilic and non-eosinophilic phenotypes will be compared to a benchmark (published results from a similar study population). Data for this study will be sourced from the International Severe Asthma Registry (ISAR). Parallel analyses using a primary care observational database, the Optimum Patient Care Research Database (OPCRD), will be conducted for providing a benchmark for comparison.