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

Thromb Haemost. 2014 Jun;111(6):1167-76. doi: 10.1160/TH14-03-0231. Epub 2014 Apr 1.

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.

Keywords: Atrial fibrillation; anticoagulation; cost-effectiveness; screening; stroke prevention.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Algorithms
  • Atrial Fibrillation / diagnosis*
  • Atrial Fibrillation / epidemiology
  • Cell Phone*
  • Community Health Services
  • Cost-Benefit Analysis
  • Cross-Sectional Studies
  • Diagnosis, Computer-Assisted / economics
  • Diagnosis, Computer-Assisted / methods*
  • Electrocardiography / instrumentation
  • Electrocardiography / methods*
  • Electrocardiography / statistics & numerical data
  • Female
  • Humans
  • Male
  • Mass Screening / economics
  • Mass Screening / methods
  • New South Wales / epidemiology
  • Pharmacies*
  • Pharmacists
  • Prevalence
  • Quality-Adjusted Life Years
  • Stroke / economics
  • Stroke / prevention & control*

Associated data

  • ANZCTR/ACTRN12612000406808