Initial step-up treatment changes in asthmatic children already prescribed inhaled corticosteroids: a historical cohort study.

Background: When standard doses of inhaled corticosteroids (ICS) fail to control symptoms in children aged >4 years, guidelines recommend the addition of a long-acting β2-agonist (LABA), with other treatment options being available if symptoms persist.
Aims: To determine the proportion of initial 'step-up' episodes where LABAs were prescribed and to describe characteristics of individuals not stepped up with LABA.
Methods: Between 1999 and 2011, initial step-up episodes from ICS monotherapy were identified in children aged 5-12 years with asthma and in receipt of ICS. Data sources were the Clinical Practice Research Datalink and Optimum Patient Care Research Database.
Results: Initial step-up episodes were identified in 10,793 children. ICS dose was increased in 6,252 children (58%), LABA was introduced in 3,436 (32%; including 1,107 where fixed dose combination inhaler (FDC) replaced the ICS inhaler), and leukotriene receptor antagonist (LTRA) was added in 1,105 (10%). Compared with children stepped up to any LABA, others were younger and prescribed lower doses of ICS and reliever medication. ICS dose increase was more likely in obese children and LTRA prescribing was more likely in children with rhinitis and in receipt of antibiotics. Compared with FDC, step-up to separate LABA inhaler was more likely in younger, obese children who were using less oral steroids.
Conclusions: One-third of initial step-up episodes in children with asthma treated with ICS are to add LABA. Different characteristics of children prescribed therapies other than LABA suggest that prescribers tailor treatment in some clinical settings.