Introduction Symptoms of breathlessness in people referred to a Tertiary Airways and Severe Asthma service may be due to a variety of treatable conditions, including asthma, inducible laryngeal obstruction (Ilo) and breathing pattern disorder (BPD). Previous research has shown overlap between asthma and Ilo (Low et al, 2011), and between asthma and BPD (Boulding et al., 2016). In clinical practice, overlap between Ilo and BPD is also common, but this has not been consistently shown in research. Aims and objectives To explore the incidence of Ilo, asthma and BPD and the overlap between these conditions in a sample of patients referred to a tertiary airways service, and to investigate patient characteristics associated with each condition. Methods Patient notes were reviewed for people referred to a tertiary airways service for symptoms of breathlessness over an 18 month period. Assessment information was collated for patients (n=306) diagnosed with asthma, Ilo and/or BPD. Results Of the 306 patients, 235 (77%) were diagnosed with Ilo via videolaryngoscopy, 177 (58%) were diagnosed with asthma, and 83 (27%) were diagnosed with BPD. There was significant overlap between the three conditions, with 186 patients (52%) having at least two conditions. The most common overlap was between asthma and Ilo (30% of patients), followed by Ilo and BPD (11%). In contrast, only 3% of patients in this sample had both asthma and BPD. All three conditions were seen in 9% of patients. A visual representation of overlap is presented in figure 1 below: Of the three conditions, Ilo most commonly co-occurred with asthma, whilst BPD most commonly co-occurred with Ilo. When BPD co-occurred with asthma, this was most commonly seen together with Ilo. Conclusions This study showed high levels of overlap between conditions that can contribute to symptoms of breathlessness. This emphasises the importance of a multi-professional assessment and optimisation of comorbid treatable traits, such as Ilo and BPD. It may also serve as a reminder for a timely referral for specialist assessment and management of treatable traits to avoid the potential of morbidity, increased healthcare utilisation and over-medication in severe and difficult to treat asthma.
