Patients with severe asthma continue to pose a challenge for providers. While they account for only 3%-10% of the overall asthma population, their care consumes 60% of all asthma-related medical expenditures. The American Thoracic Society and European Respiratory Society issued guidelines on the evaluation and treatment of severe asthma in 2014, and in the first quarter of 2020, several papers published in the journal CHEST have addressed severe asthma management.
A review published in January by authors from the National Heart, Lung, and Blood Institute (NHLBI) summarized recent data on the type 2-low (T2L) asthma endotype. T2L is sometimes referred to as "noneosinophilic" or "neutrophilic" asthma, and although these terms aren't precisely synonymous, they will be used interchangeably here.
The hallmark of T2L asthma is a poor response to corticosteroids. Corticosteroid therapies, whether inhaled or oral, are considered a staple of asthma treatment in all guidelines. Depending on which sample is studied, anywhere from 50% to 70% of all asthmatics are the T2L endotype. The conclusion is chilling ─ a large portion of asthmatics, maybe even a majority, won't respond to our most effective therapy. How often do we chase T2L asthma with higher and higher doses of inhaled and oral corticosteroids
