Evaluation of a Mobile Direct Observation Therapy (DOT) Approach in Children and Young People With Asthma. Pilot Study

Asthma is the most common chronic disease in childhood. It is defined as a chronic inflammatory disorder of the airways in which many cells and cellular elements promote airway obstruction and hyper-responsiveness (GINA, 2012). According to the World Health Organization (WHO, 2014), asthma is estimated to affect approximately 253 million people worldwide. Despite advances in biological and pathological research, the prevalence of asthma in children has significantly increased over the past decade (Massingham et al., 2014).

Moreover, the economic burden of asthma is increasing. In the US, it is estimated that the yearly cost of asthma in children and adults is around $1.48 billion (Price et al., 2013). A decade ago, the total annual asthma expenditure in the UK was determined to be £752.6 million with 8% of costs associated with hospital admission, 13% attributable to general practitioner consultations and 79% due to prescription costs (Gupta et al., 2004).

The British Thoracic Society (BTS/SIGN, 2012) and Global Initiative for Asthma (GINA, 2012) guidelines provide the background definitions for three broad categories of asthma control. They include controlled (no nocturnal wakening, infrequent short acting beta 2 agonist (SABA) use e.g. < 2 puffs/week, occasional mild symptoms e.g. with exercise and no exacerbations in last 3 months), partially controlled (nocturnal wakening < 3 nights/week, SABA use e.g. < 4 puffs/day, mild limitation in exercise tolerance due to asthma, and 2 or fewer mild exacerbations in the previous 3 months) or uncontrolled (nocturnal wakening 4-7 nights/week, SABA use e.g. > 5 puffs/day, limitation in exercise tolerance due to asthma and or significant asthma exacerbations requiring oral steroid, Emergency Department attendance or hospital admission in the previous 3 months). Children who present with partially controlled or uncontrolled asthma can be divided into difficult to treat asthma (DTA) and true severe therapy resistant asthma (STRA) after careful investigation (Hedlin et al., 2012). DTA occurs when asthma is uncontrolled but the impact of concomitant disorders and the basics of asthma care (inhaler technique and adherence) have not been adequately resolved.

Many children with asthma can achieve symptom and disease control by using inhaled corticosteroid (ICS) therapy combined with a long acting B2 agonist (LABA) and/or a leukotriene receptor antagonist (LTRA) (International ERS/ATS guideline, 2014). However, a number of children with asthma experience frequent symptoms despite being prescribed high dose ICS (Nagakumar and Thomas, 2013; Hedlin et al., 2014).

Drug delivery by inhalation of various medications is the most common treatment approach for asthma in all patient populations. Inhalation therapy offers rapid onset and improved efficacy compared to systemic drug delivery (Bisgaard, 1997). While ICS therapy is well accepted as the foundation of optimal therapy for most asthma patients, efficacy of the therapy depends on drug being delivered correctly into the lungs and taken on a regular basis as a preventer therapy (Machira et al., 2011).