Conclusions and Relevance Although screening with ECG can detect previously unknown cases of atrial fibrillation , it has not been shown to detect more cases than screening focused on pulse palpation .
Treatments for atrial fibrillation reduce the risk of stroke and all-cause mortality and increase the risk of bleeding , but trials have not assessed whether treatment of screen-detected asymptomatic older adults results in better health outcomes than treatment after detection by usual care or after symptoms develop
Importance Atrial fibrillation is the most common arrhythmia and increases the risk of stroke .
Objective To review the evidence on screening for nonvalvular atrial fibrillation with electrocardiography ( ECG ) and stroke prevention treatment in asymptomatic adults 65 years or older to inform the US Preventive Services Task Force .
A randomised controlled trial and cost-effectiveness study of systematic screening (targeted and total population screening) versus routine practice for the detection of atrial fibrillation in people aged 65 and over. The SAFE study.
OBJECTIVES To determine the most cost-effective method of screening for  atrial fibrillation ( AF ) in the population aged 65 years and over , as well as its prevalence and incidence in this age group . Also to evaluate the relative cost-effectiveness of different methods of recording and interpreting the electrocardiogram ( ECG ) within a screening programme . DESIGN Multicentred r and omised controlled trial . Purpose fully selected general practice s were r and omly allocated to 25 intervention practice s and 25 control practice s. SETTING Fifty primary care centres across the West Midl and s , UK . PARTICIPANTS Patients aged 65 years and over . INTERVENTIONS GPs and practice nurses in the intervention practice s received education on the importance of AF detection and ECG interpretation . Patients in the intervention practice s were r and omly allocated to systematic ( n = 5000 ) or opportunistic screening ( n = 5000 ) . Prospect i ve identification of pre-existing risk factors for AF within the screened population enabled comparison between targeted screening of people at higher risk of AF and total population screening . MAIN OUTCOME MEASURES AF detection rates in systematic ally screened and opportunistically screened population s in the intervention practice s were compared with AF detection rate in 5000 patients in the control practice s. The screening period was 12 months . RESULTS Baseline prevalence of AF was 7.2 % , with a higher prevalence in males ( 7.8 % ) and patients aged 75 years and over ( 10.3 % ) . The control population demonstrated higher baseline prevalence ( 7.9 % ) than either the systematic ( 6.9 % ) or opportunistic ( 6.9 % ) intervention population . In the control population 47 new cases were detected ( incidence 1.04 % per year ) . In the opportunistic arm 243 patients without a baseline diagnosis of AF were found to have an irregular pulse , with 177 having an ECG , yielding 31 new cases ( incidence 0.69 % per year ) . A further 44 cases were detected outside the screening programme ( overall incidence 1.64 % per year ) . In the systematic arm 2357 patients had an ECG yielding 52 new cases ( incidence 1.1 % per year ) . Of these , 31 were detected by targeted screening and a further 21 by total population screening . A further 22 cases were detected outside the screening programme ( overall incidence 1.62 % per year ) . In terms of ECG interpretation , computerised decision support software ( CDSS ) gave a sensitivity of 87.3 % , a specificity of 99.1 % and a positive predictive value ( PPV ) of 89.5 % compared with the gold st and ard ( cardiologist reporting ) . GPs and practice nurses performed less well . The only difference in performance between intervention population s and controls was that practice nurses from the control arm performed less well than with intervention practice nurses on interpretation of limb-lead ( PPV 38.8 % versus 20.8 % ) and single-lead ( PPV 37.7 % versus 24.0 % ) ECGs . The within-trial economic evaluation results showed the lowest incremental cost to be for the opportunistic arm , with an incremental cost-effectiveness ratio of 337 pounds Sterling for each additional case detected compared to the control arm . Opportunistic screening dominated both more intensive screening strategies . Model-based analyses showed small differences in cost and quality -adjusted life-years for different methods and intensities of screening , but annual opportunistic screening result ed in the lowest number of ischaemic strokes and greatest proportion of cases of AF diagnosed . Probabilistic sensitivity results indicated that there was a probability of approximately 60 % that screening from the age of 65 years was cost-effective in both men and women . CONCLUSIONS The results of the study indicated that in terms of a screening programme for atrial fibrillation in patients 65 and over , the only strategy that improved on routine practice was opportunistic screening , model-based analyses indicated that there was a probability of approximately 60 % of annual opportunistic screening being cost effective . It is suggested that the following topics are worthy of further investigation : the effect of the implementation of a screening programme for AF on the uptake and maintenance of anticoagulation in patients aged 65 years and over ; an evaluation of the role of CDSS in the diagnosis of cardiac arrythmias ; the best method for routinely detecting paroxysmal AF ; ways of improving healthcare professionals ' performance in ECG interpretation ; development of a robust economic model to incorporate data on new therapeutic agents for use as thromboprophylactic agents for patients with AF , and an evaluation of the relative risk of stroke for patients with incident as opposed to prevalent AF
Conclusions and Relevance Although screening with ECG can detect previously unknown cases of atrial fibrillation , it has not been shown to detect more cases than screening focused on pulse palpation .
Treatments for atrial fibrillation reduce the risk of stroke and all-cause mortality and increase the risk of bleeding , but trials have not assessed whether treatment of screen-detected asymptomatic older adults results in better health outcomes than treatment after detection by usual care or after symptoms develop
Importance Atrial fibrillation is the most common arrhythmia and increases the risk of stroke .
Objective To review the evidence on screening for nonvalvular atrial fibrillation with electrocardiography ( ECG ) and stroke prevention treatment in asymptomatic adults 65 years or older to inform the US Preventive Services Task Force .