General practice (GP) text messaging support for medication adherence in asthma and COPD patients: a randomised controlled trial

Approximately half of patients with asthma and COPD do not take their medication as prescribed. Text message prompts delivered through primary care present an opportunity to improve inhaler adherence and symptom control at scale. Patients with asthma and/or COPD were invited to take part by their GP in this individual-level randomised controlled trial. Participants were randomized 1:1 to one of two arms: an intervention arm (SMS messaging + usual care) and a control arm (usual care only). Participants in the intervention group received a series of 23 supportive text messages over a 26-week period, reminding them to take their preventer inhaler and providing information on why the treatment is needed. The control group received usual care. The primary outcome measure was medication adherence, measured through an online survey administered to all participants at baseline, 13 and 26 weeks. A total of 5,873 participants were randomised to the intervention (n=2929) and control (n=2944) groups. At 13 and 26 weeks, self-reported medication adherence was significantly higher for the intervention group than the control for both the asthma and COPD groups (p<.0001), although patients with asthma in the intervention group had a longer interval between issued inhaler prescriptions. Symptom control on the Asthma Control Test (ACT) was significantly better in asthma patients who received the intervention compared to those who did not at both 13 (p<.001) and 26 weeks (p=.002). No effect was observed on symptom control for COPD patients and no differences were seen in healthcare utilisation.