Mass Screening for Untreated Atrial Fibrillation: The STROKESTOP Study
Background—The aim of the present study was to define the prevalence of untreated atrial fibrillation (AF) in a systematic screening program using intermittent ECG recordings among 75/76-year-old individuals and to study the feasibility of initiating protective oral anticoagulant treatment (OAC).
Methods and Results—Half of the 75/76-year-old population in two Swedish regions were invited to a screening program for AF. Participants without a prior diagnosis of AF underwent intermittent ECG recordings over two weeks. If AF was detected participants were offered OAC. During the 28-month inclusion period 13 331 inhabitants were invited. Of these, 7173 (53.8%) participated. Of the participants, n=218, 3.0% (95 % confidence interval (CI) 2.7-3.5%) were found to have previously unknown AF, of these 37 (0.5 % of the screened population) were found on their first ECG. The use of intermittent ECGs increased new AF detection 4-fold. A prior diagnosis of AF was known in 9.3%, (CI 8.6-10.0%, n=666). Total AF prevalence in the screened population was 12.3%. Of participants with known AF n=149 (2.1%, CI 1.8-2.4%) had no OAC treatment. In total, 5.1% (CI 4.6-5.7%) of the screened population had untreated AF; screening resulted in initiation of OAC treatment in 3.7% (CI 3.3-4.2%) of the screened population. More than 90% of the participants with previously undiagnosed AF accepted initiation of OAC treatment.
Conclusions—Mass-screening for AF in a 75/76-year-old population identifies a significant proportion of participants with untreated AF. Initiation of stroke prophylactic treatment was highly successful in individuals with newly diagnosed AF.
Clinical Trial Registration Information—ClinicalTrials.gov. Identifier: NCT01593553.
- Received November 20, 2014.
- Revision received April 9, 2015.
- Accepted April 16, 2015.