The cost vs the benefit of community screening for disease is often hotly debated. A new study suggests that detection and treatment of asymptomatic AF may be worth that effort.
As the incidence of occult, asymptomatic atrial fibrillation (AF) continues to rise, more attention has been focused on whether community-wide screening efforts may become an important intervention for reducing disease-associated morbidity. The 2012 European Society of Cardiology (ESC) AF guidelines recommend only targeted screening with Holter monitor or ECG in select patients. However, new data made available in the past few months suggest that screening the general population not only may becost-effective but also may lower overall incidence of stroke and mortality.
In a preliminary study presented at the ESC Congress in Barcelona, Spain, in August 2014 and published in Thrombosis and Haemostasis, Martinez and coauthors analyzed the prognosis of incidentally discovered ambulatory AF (IA-AF). Subjects were excluded if they had a history of valvular heart disease or heart failure; used digoxin, quinidine, sotatol, amiodarone, flecainide, or propafenone; had a recording with irregular beats; had undergone DCCV cardioversion; used oral anticoagulants in the preceding year; or had an endpoint event.
The prospective cohort study included 5555 outpatients with IA-AF in the UK (61.6% men; mean CHA2DS2VASc score, 2.5 ± 1.5) and 24,000 age- and sex-matched controls without AF. During the 3 years of follow-up, both stroke (19.4% vs 8.4%) and mortality (40.1% vs 8.4%) were significantly increased in patients with IA-AF vs controls without AF. Next, the authors reported that with the initiation of an oral anticoagulant with or without antiplatelet therapy in 51% of IA-AF patients in the first year, there was a 65% lower hazard for stroke and a 44% lower mortality.
Although these data are not randomized, the results are compelling because they underscore that IA-AF carries a prognosis similar to that of symptomatic AF and that with treatment, the morbidity and mortality can be reduced. As such, the evidence is mounting that community screening is effective for decreasing the burden of complications from AF and may eventually become part of the routine guidelines.
See related article on cost-effectiveness of iPhone-based community screening for AF.
Martinez C, Katholing A, Freedman SB, et al. Adverse prognosis of incidentally detected ambulatory atrial fibrillation. Thromb Haemost 2014; 112:276-286.