Abstract
The period of adolescence and young adulthood (AYA) has been proposed to extend from 11 to 25 years of age as patients in this age group face similar challenges. AYA is a time of fast and great physiological and psychological growth, in which an individual transitions from a young dependent child to a mature independent adult. Behaviour patterns during adolescence, such as risk taking and desire for privacy, can challenge parents or healthcare professionals' (HCPs') ability to help adolescents to manage their asthma. Asthma itself tends to remit, become milder or worsen into a severe variant during adolescence. The pre-pubertal male predominance of asthma switches to a female predominance in late teen years. ∼10% of AYA with asthma have "difficult-to-treat asthma (DTA)", characterised by poor asthma control despite treatment with inhaled corticosteroids (ICS) and other controller medications. DTA management in AYA requires a multidisciplinary team approach and systematic assessment that can address the key questions of objective confirmation of diagnosis, severity assessment, phenotyping, comorbidities, asthma mimickers or other drivers of poor control such as non-adherence to treatment. A key task for HCPs is to establish the magnitude of the severe asthma component versus other non-asthma drivers of symptoms (e.g. inducible laryngeal obstruction or breathing pattern disorder). Severe asthma is a subset of DTA and is determined once asthma diagnosis and its severity have been confirmed and adherence to controller (ICS) treatment has been assured. Severe asthma is a heterogeneous disease and appropriate phenotyping is necessary for the management of treatable traits and consideration for biologic therapies. Finally, an important part of successful management of DTA in the AYA group is the provision of an effective transition of asthma care from paediatric to adult asthma services through setting up a well-designed asthma transition pathway tailored to the individual patient needs.