The frequency of, and adherence to, single maintenance and reliever therapy instructions in asthma: a descriptive analysis.

Inhaled corticosteroid/long-acting β2-agonist (ICS/LABA) fixed-dose combinations are recommended regular maintenance options for asthma. ICS/LABAs containing formoterol may also be indicated for single maintenance and reliever therapy (SMART). This analysis evaluated the frequency of SMART dosing of budesonide/formoterol fixed-dose combination (BFC) in the United Kingdom. Secondary objectives were to assess adherence and use of short-acting ß2-agonists (SABAs). This was a descriptive analysis of treatment patterns using the UK Clinical Practice Research Datalink-GP OnLine Database data (2009-2013). SMART dosing was determined when prescription instructions contained guidance for daily dosing plus 'and when required'. Treatment and prescription refill patterns of BFC and SABA were described in the year following the index date to identify adherence and SMART dosing instructions versus other dosing regimens. Of 14,818 patients identified, 173 (1.2%) had evidence of prescriptions for SMART dosing at their index BFC prescription. Despite being prescribed SMART dosing, 91 of 173 patients (53%) were additionally dispensed SABA in the year following the index date. The mean number of BFC inhalers used was less than required for daily treatment for SMART and non-SMART dosing groups (4.7 and 4.8, respectively).This analysis suggests that SMART dosing is infrequent when examining dosing instructions. Therefore, results of randomised clinical trials using SMART dosing may not translate to clinical practice in the United Kingdom because of the low level of SMART prescription, concurrent use of SABA, and inadequate refill persistence observed. Further research is needed to understand SMART dosing in real-world clinical practice.