The Systematic Assessment of Difficult-to-Treat Asthma: Why Do It?

Abstract

Approximately 5% of asthmatics have severe refractory disease, and this group of patients have a high morbidity and raised mortality. There is an additional and substantial cost to the economy. Within this group, some patients may have an alternative diagnosis while others may appear to be severe because of poor compliance with prescribed therapy. The identification of comorbid disease and specific triggers can help direct therapy. Patients with severe, treatment-resistant asthma are a heterogeneous group and exhibit specific clinical features, physiological measurements, and biomarkers. This produces a phenotypic handprint, which may enable targeted therapy in certain patients. The use of steroid-sparing medications, such as cyclosporine or methotrexate, or novel biologics such as anti-IgE (Omalizumab) requires a thorough review of the patient and systematic investigation to ensure that they are suitable for therapy, which may be expensive or unlicensed for severe asthma and in some cases has the potential for serious side effects. This process can be achieved through systematic assessment of asthma (SAA); which comprises a set of coordinated investigations accompanying a detailed history and examination. The SAA provides a structured and thorough assessment. In addition, it forms a valuable database and tool for research. With the advent of new monoclonal antibodies and other immunological agents for severe asthma, the SAA approach will become an increasingly important assessment tool.