The question we will be answering: is screening for AF effective and cost effective in reducing stroke and other key outcomes compared to current practice?
To do this we are breaking the programme of work down into the following main areas:
Feasibility study 1 – complete
We have conducted a feasibility study in 10 GP practices in the East of England. This has confirmed it is feasible to deliver an AF screening programme in general practice, and that high numbers of patients accept an offer of AF screening and go on to complete the screening process. This enabled us to finalise the design of the cluster randomised controlled pilot trial in light of our findings. The feasibility study 1 is registered with the ISRCTN.
Feasibility study 2 (screening at home) – complete
We were about to start the cluster randomised controlled trial in March 2020 when the COVID-19 pandemic struck. It was clear that we could not at that time continue with screening delivered in the practice. We therefore added a second feasibility study to test screening at home. Working with 3 GP practices in the East of England we tested a number of different approaches to delivering the AF screening intervention, to see if any of these approaches can be used for the subsequent trial.
Cluster randomised controlled pilot trial – complete
We have completed recruitment to the pilot trial in 39 practices, who have recruited over 14,000 patients. In this stage, one third of practices (13) undertook AF screening and the remainder (26) did not (controls). The patients in the screening practices have finished screening. This helped us to decide if:
- the screening programme needed refinement;
- screening identified the number of new cases of AF that we expected;
- sufficient numbers of newly identified people with AF were started on blood thinning (anticoagulation) therapy;
- screening caused any undue worry in people.
Randomised controlled trial – now recruiting
We are now carrying out the next stage in the programme, an experiment in about 170 general practices across England involving 82,000 patients in which one third of patients recruited at each practice will be offered AF screening. Screening is being done at home. We will follow up participants for four years without having any further direct contact with them. We will see if screening leads to fewer strokes, heart attacks and deaths, and whether it increases the risk of serious bleeding (the main harm associated with anticoagulants).
We will carry out case studies in some practices to clarify how to carry out screening, both in the trial, and in a potential national screening programme. These studies will involve observing what goes on in practices when carrying out screening, and interviewing staff and patients. We particularly want to explore:
- issues around consent to screening;
- sharing decision making about treatment if AF is found;
- factors associated with uptake of screening;
- patient concerns.
Some participants will be sent health questionnaires to complete at various stages in the trial.
Cost effectiveness analysis
We will determine if screening does lead to fewer strokes, and whether this is good use of NHS resources.
The trial is registered with the ISRCTN.