Feasibility and cost-effectiveness of stroke prevention through community screening for atrial fibrillation using iPhone ECG in pharmacies: The SEARCH-AF study

Lowres, N.; Neubeck, L.; Salkeld, G.; Krass, I.; McLachlan, A. J.; Redfern, J.; Bennett, A. A.; Briffa, T.; Bauman, A.; Martinez, C.; Wallenhorst, C.; Lau, J. K.; Brieger, D. B.; Sy, R. W.; Freedman, S. B.

Abstract

Atrial fibrillation (AF) causes a third of all strokes, but often goes undetected before stroke. Identification of unknown AF in the community and subsequent anti-thrombotic treatment could reduce stroke burden. We investigated community screening for unknown AF using an iPhone electrocardiogram (iECG) in pharmacies, and determined the cost-effectiveness of this strategy.Pharmacists performedpulse palpation and iECG recordings, with cardiologist iECG over-reading. General practitioner review/12-lead ECG was facilitated for suspected new AF. An automated AF algorithm was retrospectively applied to collected iECGs. Cost-effectiveness analysis incorporated costs of iECG screening, and treatment/outcome data from a United Kingdom cohort of 5,555 patients with incidentally detected asymptomatic AF. A total of 1,000 pharmacy customers aged ≥65 years (mean 76 ± 7 years; 44% male) were screened. Newly identified AF was found in 1.5% (95% CI, 0.8-2.5%); mean age 79 ± 6 years; all had CHA2DS2-VASc score ≥2. AF prevalence was 6.7% (67/1,000). The automated iECG algorithm showed 98.5% (CI, 92-100%) sensitivity for AF detection and 91.4% (CI, 89-93%) specificity. The incremental cost-effectiveness ratio of extending iECG screening into the community, based on 55% warfarin prescription adherence, would be $AUD5,988 (€3,142; $USD4,066) per Quality Adjusted Life Year gained and $AUD30,481 (€15,993; $USD20,695) for preventing one stroke. Sensitivity analysis indicated cost-effectiveness improved with increased treatment adherence.Screening with iECG in pharmacies with an automated algorithm is both feasible and cost-effective. The high and largely preventable stroke/thromboembolism risk of those with newly identified AF highlights the likely benefits of community AF screening. Guideline recommendation of community iECG AF screening should be considered.

Citation

Lowres, N., Neubeck, L., Salkeld, G., Krass, I., McLachlan, A. J., Redfern, J., …Freedman, S. B. (2014). Feasibility and cost-effectiveness of stroke prevention through community screening for atrial fibrillation using iPhone ECG in pharmacies: The SEARCH-AF study. Thrombosis and Haemostasis, 111(6), 1167-1176. https://doi.org/10.1160/th14-03-0231

• Journal Article Type: Article
• Acceptance Date: Mar 19, 2014
• Online Publication Date: Apr 1, 2014
• Publication Date: 2014
• Deposit Date: Oct 28, 2016
• Print ISSN: 0340-6245
• Publisher: Schattauer
• Peer Reviewed: Peer Reviewed
• Volume: 111
• Issue: 6
• Pages: 1167-1176
• DOI: https://doi.org/10.1160/th14-03-0231
• Keywords: Atrial fibrillation, anticoagulation, cost-effectiveness, screening, stroke prevention,
• Public URL: http://researchrepository.napier.ac.uk/Output/409439