John: Hello, I'm John Hilton, editor of the Cochrane Editorial unit. Alongside the several existing Cochrane Reviews of steroids for adults and children with asthma, in April 2017 the Cochrane Airways Group added a new review of interventions to improve adherence to these drugs. We asked Rebecca Normansell and Liz Stovold, both authors on the review and members of staff with Cochrane Airways, to tell us more in this podcast, starting with Rebecca.

Rebecca: Inhaled steroids are one of the most effective treatments for asthma but many people often miss doses. They forget, don’t fully understand the importance of using their inhaler, or become worried about side effects. This poor adherence has negative consequences and a recent review in the UK reported that it contributed to one-third of asthma deaths.
Our review looks at possible ways of helping people with asthma to take their inhaler as prescribed, to see if these interventions could improve adherence and lead to better outcomes, such as fewer asthma attacks and improved asthma control.

Liz: We found a large number of studies, 39 in total which were suitable for inclusion. The largest study recruited nearly 1,000 people and the smallest just 12. Studies lasted two to 24 months, and 18 of them involved only children.
We grouped studies into one of four main comparisons. The first, and largest with 20 studies, was adherence education versus control. People receiving the education had on average adherence that was 20 percentage points higher than the control group. But the way the individual studies were conducted and the fact that their results are quite different to one another means that we cannot be very certain about the robustness of this finding.
The second group, with 11 studies, looked at electronic inhaler reminders. People receiving these reminders had on average adherence that was 19 percentage points higher than the control group. Although we have some concerns about the way some of these studies were conducted, we’re moderately confident in this finding.
The third group, comparing simplified versus usual drug regimens included just four studies, and found that adherence in the intervention group improved by on average four percentage points. Finally, the fourth group of three trials studied school-based inhaler therapy but adherence data weren’t available for these trials.

Rebecca: Overall, despite the improvements in adherence with some of the interventions, we did not see clear benefits for asthma attacks or asthma control, although some individual studies did report fewer attacks and reduced use of healthcare services.
In summary, our review shows that there are interventions that might improve adherence to inhaled steroids in adults and children, and it is very important to have regular discussions about adherence with people with asthma. However, we did not find strong evidence about whether specific interventions will lead to better asthma outcomes and some of the programmes are complex and likely to be expensive so it may be difficult to implement them in a real life setting.

John: If you would like to explore the programmes that have been evaluated in more detail and read about the full effects of the four categories of intervention that Rebecca and Liz mentioned, it’s easy to find the review. Just go to Cochrane Library dot com and search 'steroid adherence'.