Opportunistic AF screening increased participation among invited individuals and identified a higher-risk population, but its overall population reach was limited by incomplete eligibility assessment, suggesting that combining opportunistic and systematic strategies may optimize reach and participation in AF screening programmes.
Participation rate among invited eligible individuals was significantly higher in opportunistic screening compared to systematic screening.
Overall population reach was significantly lower in the opportunistic screening arm compared to the systematic screening arm.
Participants in the opportunistic screening arm had a higher cardiovascular risk burden than those in the systematic screening arm.
A large proportion of potentially eligible individuals in the opportunistic arm were never assessed for screening eligibility.
STROKESTOP III was a cluster-randomized trial of AF screening in 75–76 year-old individuals across 16 primary care centres in Region Värmland, Sweden.
This research compared two approaches to screening older adults for atrial fibrillation (AF), an irregular heart rhythm that increases stroke risk. In 'systematic' screening, everyone in the target age group (75–76 year-olds) received a mailed invitation to be screened. In 'opportunistic' screening, individuals were invited only when they happened to visit their primary care centre. The study found that when people were actually invited, they were more likely to say yes under the opportunistic approach (61% vs. 46%). However, because nearly half of eligible people visiting the clinics were never offered the screening at all, the opportunistic approach reached far fewer people overall (25% vs. 42% of the target population). The study also found that people who participated through opportunistic screening tended to have more health problems — more hypertension, diabetes, and a higher overall stroke risk score — compared to those who participated through systematic screening. This makes sense, as people who visit their doctor more frequently likely have more health issues. On the downside, more people in the opportunistic group had to be excluded because they already had a diagnosed AF or had cognitive impairment. This research suggests that neither approach alone is ideal for AF screening programs. Opportunistic screening attracts a higher proportion of those who are invited and finds higher-risk patients, but misses large numbers of people who don't happen to visit a clinic. Systematic screening reaches more of the overall population but has lower uptake among those invited. The authors suggest that combining both strategies could be the most effective way to maximize both reach and participation in future AF screening programs.
Khan M, Skröder S, Ingre M, Carlstedt F, Eriksson A, Star Tenn J, et al.. (2026). Population reach and participation rate in opportunistic vs. systematic atrial fibrillation screening: STROKESTOP III.. Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology. https://doi.org/10.1093/europace/euag214