title: Cost-Effectiveness of a National Opportunistic Screening Program for Atrial Fibrillation in Ireland. Screening versus routine practice in detection of atrial fibrillation in patients aged 65 or over: cluster randomised controlled trial Prevalence of atrial fibrillation in Spain. OFRECE study results. Subclinical atrial fibrillation and the risk of stroke. The prevalence, incidence, management and risks of atrial fibrillation in an elderly Chinese population: a prospective study The DanCavas Pilot Study of Multifaceted Screening for Subclinical Cardiovascular Disease in Men and Women Aged 65-74 Years. Assessment of Remote Heart Rhythm Sampling Using the AliveCor Heart Monitor to Screen for Atrial Fibrillation: The REHEARSE-AF Study 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. Opportunistic screening for atrial fibrillation versus detecting symptomatic patients aged 65 years and older: A cluster-controlled clinical trial. Effect of a Home-Based Wearable Continuous ECG Monitoring Patch on Detection of Undiagnosed Atrial Fibrillation: The mSToPS Randomized Clinical Trial Diagnostic accuracy and yield of screening tests for atrial fibrillation in the family practice setting: a multicentre cohort study. Major progress in anticoagulant uptake for atrial fibrillation at last: does it translate into stroke prevention?
abstract: OBJECTIVES To evaluate the cost-effectiveness of a  national atrial fibrillation screening program in Irel and involving annual opportunistic pulse palpation of all those older than 65 years during general practitioner consultations , with an electrocardiogram being performed if an irregular pulse is detected . METHODS A probabilistic Markov model was used to simulate costs and clinical outcomes in a hypothetical cohort of men and women with and without screening over the course of 25 years , using a societal perspective . RESULTS Screening was associated with an incremental cost-effectiveness ratio of € 23,004/ quality -adjusted life-year compared with routine care . Nevertheless , if the relative risk of stroke and systematic embolism in screen-detected patients is more than 12 % lower than that in patients with atrial fibrillation identified through routine practice , then screening would not be considered cost-effective at a willingness-to-pay threshold of € 45,000/ quality -adjusted life-year . An analysis comparing alternative combinations of start age and screening interval found that less frequent screening with a later start age may be more cost-effective than an annual screening from age 65 years . CONCLUSIONS Annual opportunistic screening of men and women aged 65 years and older in primary care in Irel and is likely to be cost-effective using conventional willingness-to-pay thresholds , assuming that those detected through screening have a comparable stroke risk profile as those detected through routine practice . Raising the start age of screening or increasing the screening interval may improve the cost-effectiveness of a prospect i ve screening program Objectives To assess whether screening improves the detection of atrial fibrillation  ( cluster r and omisation ) and to compare systematic and opportunistic screening . Design Multicentred cluster r and omised controlled trial , with subsidiary trial embedded within the intervention arm . Setting 50 primary care centres in Engl and , with further individual r and omisation of patients in the intervention practice s. Participants 14 802 patients aged 65 or over in 25 intervention and 25 control practice s. Interventions Patients in intervention practice s were r and omly allocated to systematic screening ( invitation for electrocardiography ) or opportunistic screening ( pulse taking and invitation for electrocardiography if the pulse was irregular ) . Screening took place over 12 months in each practice from October 2001 to February 2003 . No active screening took place in control practice s. Main outcome measure Newly identified atrial fibrillation . Results The detection rate of new cases of atrial fibrillation was 1.63 % a year in the intervention practice s and 1.04 % in control practice s ( difference 0.59 % , 95 % confidence interval 0.20 % to 0.98 % ) . Systematic and opportunistic screening detected similar numbers of new cases ( 1.62 % v 1.64 % , difference 0.02 % , −0.5 % to 0.5 % ) . Conclusion Active screening for atrial fibrillation detects additional cases over current practice . The preferred method of screening in patients aged 65 or over in primary care is opportunistic pulse taking with follow-up electrocardiography . Trial registration Current Controlled Trials IS RCT N19633732 INTRODUCTION AND OBJECTIVES Atrial fibrillation is associated with substantial morbidity and mortality and both its incidence and prevalence are high . Nevertheless , comprehensive data on this condition in Spain are lacking . The aim of this study was to estimate the prevalence of atrial fibrillation in Spain . METHODS A cross-sectional study was conducted in the general Spanish population older than 40 years . Two-stage r and om sampling was used , in which first-stage units were primary care physicians r and omly selected in every Spanish province and second-stage units were 20 r and omly selected persons drawn from each participating physician 's assigned population . The reported prevalence was st and ardized for the age and sex distribution of the Spanish population . The  electrocardiogram recordings  were read central ly . RESULTS Overall , 8343 individuals were evaluated . The mean age was 59.2 years ( 95 % confidence interval , 58.6 - 59.8 years ) , and 52.4 % of the participants were female . The overall age-adjusted prevalence of atrial fibrillation was 4.4 % ( 95 % confidence interval , 3.8 - 5.1 ) . Prevalence was similar in both sexes , men 4.4 % ( 3.6 - 5.2 ) and women 4.5 % ( 3.6 - 5.3 ) , rising with increasing age older than 60 years . In patients older than 80 years , the prevalence was 17.7 % ( 14.1 - 21.3 ) . In 10 % of patients an unknown atrial fibrillation was diagnosed . CONCLUSIONS The prevalence of atrial fibrillation in the general Spanish population older than 40 years is high , at 4.4 % . The prevalence is similar in both sexes and rises steeply above 60 years of age . It is estimated that there are over 1 million patients with atrial fibrillation in the Spanish population , of whom over 90,000 are undiagnosed BACKGROUND One quarter of strokes are of unknown cause , and sub clinical atrial fibrillation may be a common etiologic factor . Pacemakers can detect sub clinical episodes of rapid atrial rate , which correlate with electrocardiographically documented atrial fibrillation . We evaluated whether sub clinical episodes of rapid atrial rate detected by implanted devices were associated with an increased risk of ischemic stroke in patients who did not have other evidence of atrial fibrillation . METHODS We enrolled 2580 patients , 65 years of age or older , with hypertension and no history of atrial fibrillation , in whom a pacemaker or defibrillator had recently been implanted . We monitored the patients for 3 months to detect sub clinical atrial tachyarrhythmias ( episodes of atrial rate > 190 beats per minute for more than 6 minutes ) and followed them for a mean of 2.5 years for the primary outcome of ischemic stroke or systemic embolism .  Patients with pacemakers  were r and omly assigned to receive or not to receive continuous atrial overdrive pacing . RESULTS By 3 months , sub clinical atrial tachyarrhythmias detected by implanted devices had occurred in 261 patients ( 10.1 % ) . Sub clinical atrial tachyarrhythmias were associated with an increased risk of clinical atrial fibrillation ( hazard ratio , 5.56 ; 95 % confidence interval [ CI ] , 3.78 to 8.17 ; P<0.001 ) and of ischemic stroke or systemic embolism ( hazard ratio , 2.49 ; 95 % CI , 1.28 to 4.85 ; P=0.007 ) . Of 51 patients who had a primary outcome event , 11 had had sub clinical atrial tachyarrhythmias detected by 3 months , and none had had clinical atrial fibrillation by 3 months . The population attributable risk of stroke or systemic embolism associated with sub clinical atrial tachyarrhythmias was 13 % . Sub clinical atrial tachyarrhythmias remained predictive of the primary outcome after adjustment for predictors of stroke ( hazard ratio , 2.50 ; 95 % CI , 1.28 to 4.89 ; P=0.008 ) . Continuous atrial overdrive pacing did not prevent atrial fibrillation . CONCLUSIONS Sub clinical atrial tachyarrhythmias , without clinical atrial fibrillation , occurred frequently in patients with pacemakers and were associated with a significantly increased risk of ischemic stroke or systemic embolism . ( Funded by St. Jude Medical ; ASSERT Clinical Trials.gov number , NCT00256152 . ) Background There is limited information on prevalent and incident atrial fibrillation in Chinese . We aim ed to investigate the prevalence , incidence , management and risks of atrial fibrillation in an elderly Chinese population . Methods In a population —based prospect i ve study in elderly ( ≥60 years ) Chinese , we performed cardiovascular health examinations including a 12-lead electrocardiogram at baseline in 3,922 participants  and biennially during follow-up in 2,017 participants . We collected information on vital status during the whole follow-up period . Results The baseline prevalence of atrial fibrillation was 2.0 % ( n = 34 ) in 1718 men and 1.6 % ( n = 36 ) in 2204 women . During a median 3.8 years of follow-up , the incidence rate of atrial fibrillation ( n = 34 ) was 4.9 per 1000 person-years ( 95 % confidence interval [ CI ] , 3.4–6.9 ) . In univariate analysis , both the prevalence and incidence of atrial fibrillation were higher with age advancing ( P < 0.0001 ) and in the presence of coronary heart disease ( P ≤ 0.02 ) . Of the 104 prevalent and incident cases of atrial fibrillation , only 1 ( 1.0 % ) received anticoagulant therapy ( warfarin ) . These patients with atrial fibrillation , compared with those with sinus rhythm , had significantly higher risks of all-cause ( n = 261 , hazard ratio [ HR ] 1.87 , 95 % CI , 1.09–3.20 , P = 0.02 ) , cardiovascular ( n = 136 , HR 3.78 , 95 % CI 2.17–6.58 , P < 0.0001 ) and stroke mortality ( n = 44 , HR 6.31 , 95 % CI 2.81–14.19 , P = 0.0003 ) . Conclusions Atrial fibrillation was relatively frequent in elderly Chinese , poorly managed and associated with higher risks of mortality OBJECTIVE / BACKGROUND This pilot study of a large population based r and omised screening trial investigated feasibility , acceptability , and relevance ( prevalence of clinical and sub clinical cardiovascular disease [ CVD ] and proportion receiving insufficient prevention ) of a multifaceted screening for CVD . METHODS In total , 2060 r and omly selected Danish men and women aged 65 - 74 years were offered ( i ) low dose non-contrast computed tomography to detect coronary artery calcification ( CAC ) and aortic/iliac aneurysms ; ( ii ) detection of atrial fibrillation ( AF ) ; ( iii ) brachial and ankle blood pressure measurements ; and ( iv ) blood levels of cholesterol and hemoglobin A1c . Web based self booking and data management was used to reduce the administrative burden . RESULTS Attendance rates were 64.9 % ( n = 678 ) and 63.0 % ( n = 640 ) for men and women , respectively . In total , 39.7 % received a recommendation for medical preventive actions . Prevalence of aneurysms was 12.4 % ( 95 % confidence interval [ CI ] 9.9 - 14.9 ) in men and 1.1 % ( 95 % CI 0.3 - 1.9 ) in women , respectively ( p < .001 ) . A CAC score > 400 was found in 37.8 % of men and 11.3 % of women ( p < .001 ) , along with a significant increase in median CAC score with age ( p = .03 ) . Peripheral arterial disease was more prevalent in men ( 18.8 % , 95 % CI 15.8 - 21.8 ) than in women ( 11.2 % , 95 % CI 8.7 - 13.6 ) . No significant differences between the sexes were found with regard to newly discovered AF ( men 1.3 % , women 0.5 % ) , potential hypertension ( men 9.7 % , women 11.5 % ) , hypercholesterolemia ( men 0.9 % , women 1.1 % ) or diabetes mellitus ( men 2.1 % , women 1.3 % ) . CONCLUSION Owing to the higher prevalence of severe conditions , such as aneurysms and CAC ≥ 400 , screening for CVD seemed more prudent in men than women . The attendance rates were acceptable compared with other screening programs and the logistical structure of the screening program proved successful Background : Asymptomatic atrial fibrillation ( AF ) is increasingly common in the aging population and implicated in many ischemic strokes . Earlier identification of AF with appropriate anticoagulation may decrease stroke morbidity and mortality . Methods : We conducted a r and omized controlled trial of AF screening using an AliveCor Kardia monitor attached to a WiFi-enabled iPod to obtain ECGs ( iECGs ) in ambulatory patients . Patients ≥65 years of age with a CHADS-VASc score ≥2 free from AF were r and omized to the iECG arm or routine care ( RC ) . iECG participants acquired iECGs twice weekly over 12 months ( plus additional iECGs if symptomatic ) onto a secure study server with overread by an automated AF detection algorithm and by a cardiac physiologist and /or consultant cardiologist . Time to diagnosis of AF was the primary outcome measure . The overall cost of the devices , ECG interpretation , and patient management were captured and used to generate the cost per AF diagnosis in iECG patients . Clinical events and patient attitudes/experience were also evaluated . Results : We studied 1001 patients ( 500 iECG , 501 RC ) who were 72.6±5.4 years of age ; 534 were female . Mean CHADS-VASc score was 3.0 ( heart failure , 1.4 % ; hypertension , 54 % ; diabetes mellitus , 30 % ; prior stroke/transient ischemic attack , 6.5 % ; arterial disease , 15.9 % ; all CHADS-VASc risk factors were evenly distributed between groups ) . Nineteen patients in the iECG group were diagnosed with AF over the 12-month study period versus 5 in the RC arm ( hazard ratio , 3.9 ; 95 % confidence interval=1.4–10.4 ; P=0.007 ) at a cost per AF diagnosis of $ 10 780 ( £ 8255 ) . There was a similar number of stroke/transient ischemic attack/systemic embolic events ( 6 versus 10 , iECG versus RC ; hazard ratio=0.61 ; 95 % confidence interval=0.22–1.69 ; P=0.34 ) . The majority of iECG patients were satisfied with the device , finding it easy to use without restricting activities or causing anxiety . Conclusions : Screening with twice-weekly single-lead iECG with remote interpretation in ambulatory patients ≥65 years of age at increased risk of stroke is significantly more likely to identify incident AF than RC over a 12-month period . This approach is also highly acceptable to this group of patients , supporting further evaluation in an appropriately powered , event-driven clinical trial . Clinical Trial Registration : URL : https://www.is rct n.com . Unique identifier : IS RCT N10709813 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 OBJECTIVE The goal of this study was to assess the effectiveness of opportunistic screening through pulse palpation in the early detection of  atrial fibrillation in subjects aged≥65 years versus detection through an active search for patients with symptoms and /or complications and sequelae associated . MATERIAL AND METHODS This was a cluster r and omized controlled trial performed in 48 primary care centers of the Spanish National Healthcare System . A total of 368 physicians and nurses were r and omized . The research ers in the experimental group ( EG ) performed opportunistic screening for auricular fibrillation , whereas the research ers in the control group ( CG ) actively search ed for symptomatic patients . An  ECG  was performed on patients found to have an irregular heartbeat to confirm the diagnosis of auricular fibrillation . RESULTS A total of 5,465 patients with a mean age of 75.61 years were recruited for the EG , and 1,525 patients with a mean age of 74.07 years were recruited for the CG . Of these , 58.6 % were female , without significant differences between groups . Pulse was irregular in 4.3 and 15.0 % of the patients in the EG and the CG , respectively ( P<.001 ) . A total of 164 new cases of atrial fibrillation were detected ( 2.3 % ) , 1.1 % in the EG and 6.7 % in the CG ( adjusted OR : 0.29 ; 95 % CI 0.18 - 0.45 ) . CONCLUSIONS Case finding for atrial fibrillation in patients aged≥65 years with symptoms or signs suggestive of atrial fibrillation is a more effective strategy than opportunistic screening through pulse palpation in asymptomatic patients . TRIAL REGISTRATION The trial is registered in Clinical Trials.gov ( NCT01291953 ; February 8 , 2011 ) Importance Opportunistic screening for atrial fibrillation ( AF ) is recommended , and improved methods of early identification could allow for the initiation of appropriate therapies to prevent the adverse health outcomes associated with AF . Objective To determine the effect of a self-applied wearable electrocardiogram ( ECG ) patch in detecting AF and the clinical consequences associated with such a detection strategy . Design , Setting , and Participants A direct-to-participant r and omized clinical trial and prospect i ve matched observational cohort study were conducted among members of a large national health plan . Recruitment began November 17 , 2015 , and was completed on October 4 , 2016 , and 1-year cl aims -based follow-up concluded in January 2018 . For the clinical trial , 2659 individuals were r and omized to active home-based monitoring  to start immediately or delayed by 4 months . For the observational study , 2 deidentified age- , sex- and CHA2DS2-VASc – matched controls were selected for each actively monitored individual . Interventions The actively monitored cohort wore a self-applied continuous ECG monitoring patch at home during routine activities for up to 4 weeks , initiated either immediately after enrolling ( n = 1364 ) or delayed for 4 months after enrollment ( n = 1291 ) . Main Outcomes and Measures The primary end point was the incidence of a new diagnosis of AF at 4 months among those r and omized to immediate monitoring vs delayed monitoring . A secondary end point was new AF diagnosis at 1 year in the combined actively monitored groups vs matched observational controls . Other outcomes included new prescriptions for anticoagulants and health care utilization ( outpatient cardiology visits , primary care visits , or AF-related emergency department visits and hospitalizations ) at 1 year . Results The r and omized groups included 2659 participants ( mean [ SD ] age , 72.4 [ 7.3 ] years ; 38.6 % women ) , of whom 1738 ( 65.4 % ) completed active monitoring . The observational study comprised 5214 ( mean [ SD ] age , 73.7 [ 7.0 ] years ; 40.5 % women ; median CHA2DS2-VASc score , 3.0 ) , including 1738 actively monitored individuals from the r and omized trial and 3476 matched controls . In the r and omized study , new AF was identified by 4 months in 3.9 % ( 53/1366 ) of the immediate group vs 0.9 % ( 12/1293 ) in the delayed group ( absolute difference , 3.0 % [ 95 % CI , 1.8%-4.1 % ] ) . At 1 year , AF was newly diagnosed in 109 monitored ( 6.7 per 100 person-years ) and 81 unmonitored ( 2.6 per 100 person-years ; difference , 4.1 [ 95 % CI , 3.9 - 4.2 ] ) individuals . Active monitoring was associated with increased initiation of anticoagulants  ( 5.7 vs 3.7 per 100 person-years ; difference , 2.0 [ 95 % CI , 1.9 - 2.2 ] ) , outpatient cardiology visits ( 33.5 vs 26.0 per 100 person-years ; difference , 7.5 [ 95 % CI , 7.2 - 7.9 ) , and primary care visits ( 83.5 vs 82.6 per 100 person-years ; difference , 0.9 [ 95 % CI , 0.4 - 1.5 ] ) . There was no difference in AF-related emergency department visits and hospitalizations ( 1.3 vs 1.4 per 100 person-years ; difference , 0.1 [ 95 % CI , −0.1 to 0 ] ) . Conclusions and Relevance Among individuals at high risk for AF , immediate monitoring with a home-based wearable ECG sensor patch , compared with delayed monitoring , result ed in a higher rate of AF diagnosis after 4 months . Monitored individuals , compared with nonmonitored controls , had higher rates of AF diagnosis , greater initiation of anticoagulants , but also increased health care re source utilization at 1 year . Trial Registration Clinical Trials.gov Identifier : BACKGROUND Detection of undiagnosed or undertreated ( " actionable " ) atrial fibrillation could increase the use of appropriate oral anticoagulant therapy and reduce the risk of stroke . We sought to compare newer screening technologies with a pulse-check for the detection of atrial fibrillation and to determine whether the detection of actionable atrial fibrillation increases the use of oral anticoagulant agents . METHODS This prospect i ve multicentre cohort study involved 22 primary care clinics . We recruited participants aged 65 years and older who were attending routine appointments . Each participant underwent 3 methods of screening : a 30-second radial pulse-check ; single-lead electrocardiogram ; and screening by blood pressure machine with atrial fibrillation detection algorithms . Participants who received a positive result on 1 or more test underwent 12-lead electrocardiogram with or withour 24-hour Holter . Screening tests were compared using the McNemar test . Participants with confirmed atrial fibrillation received follow-up at 90 days . RESULTS The mean age of participants was 73.7 ( ± 6.9 ) years , and 53.4 % of participants were female . Of 2171 patients , we had data from all 3 screening tests for 2054 patients . Both single-lead electrocardiogram and the blood pressure device showed superior specificity compared with pulse-check ( p < 0.001 for each ) . Fifty-six patients ( 2.7 % ) had confirmed atrial fibrillation : 12 patients had newly detected atrial fibrillation ( none of the patients were using anticoagulation agents ) , and 44 patients had previously diagnosed atrial fibrillation ( 42 patients were receiving anticoagulant therapy , 2 were not ) . Thus , 14 patients had actionable atrial fibrillation ( 0.7 % ) . By 90 days , 77 % of patients with actionable atrial fibrillation had started anticoagulant therapy . INTERPRETATION Newer screening technologies showed superior specificity compared with a pulse-check . Screening detected undiagnosed or undertreated atrial fibrillation in 0.7 % of participants , and 77 % started appropriate anticoagulant therapy . TRIAL REGISTRATION Clinical Trials.gov , no. NCT02262351 A number of r and omized controlled trials in atrial fibrillation ( AF ) conducted in the last century showed that vitamin K antagonists , ( VKAs ) , principally warfarin , were remarkably effective in stroke prevention , reducing stroke by 64 % and all-cause mortality by 26 % , figures rarely matched in treatments of other diseases . With the introduction of the non-VKA anticoagulants ( NOACs ) in the last 8 years , stroke reduction in the r and omized trials was similar to VKAs , but with less intracranial haemorrhage and a further 1 % absolute risk reduction in total mortality ; results confirmed in many ‘ real-life ’ studies using administrative or registry data . Many guidelines , including the first joint AHA/ACC/ESC guideline in 2001 , recommended oral anticoagulant ( OAC ) therapy for those with AF at elevated risk of stroke , as have subsequent joint and ESC guidelines and up date s in 2006 , 2010 , 2012 , and 2016 . But OAC uptake has been less than ideal for some time , hovering in the UK at 50 % of those for whom OAC was guideline recommended , in the 10 years from 2001 to 2011 . The data from the Swedish RIKS registry of > 94 000 strokes help identify the two major gaps in prevention of AF-related strokes , which represent 33 % of all ischaemic strokes ( Take home figure ) . In 9 % of all strokes , AF was not known prior to stroke : prevention would require screening to detect and treat unknown AF . In another 20 % , AF was known but patients were either on no antithrombotic therapy ( 8 % ) or on antiplatelet therapy alone ( 12 % ) , which is largely ineffective for AF thrombo-prophylaxis . Thus , up to 20 % of ischaemic strokes might be prevented if the evidence – practice gap of OAC prescription was eliminated . It is therefore very pleasing to see in this issue of the European Heart Journal that in the UK ,  OAC use in patients with elevated stroke risk  has increased from < 50 % to almost 80 % in the 10 years from 2006 to 2016 , mostly in the latter 5 years , while  antiplatelet therapy  has reduced from 43 % to 16 % . This is a great success story , observed to some degree in many countries , but by no means uniformly , even within the same country . Trying to pinpoint the reason for this improvement is not easy . Success has many fathers , while failure is an orphan . Cowan and colleagues postulate that successive ESC and NICE guidelines , quality improvement incentivization programmes such as GRASP and QOF , or licensing and marketing of NOACs , accentuating their ease of use , could all have played a role , but it is difficult to determine which is the major one . ESC guidelines and their up date s were recommending OAC in 2001 , 2006 , and 2010 , and the GRASP quality initiative from 2009 , with little change in OAC uptake , while QOF did not commence until 2012 . It is instructive to look at our own UK data using a higher resolution temporal trend of OAC initiation within 90 days of incident AF ( Figure 1 ) . The graph plots total OAC initiations for patients with CHA2DS2-VASc > _ 2 . A rise in VKA OAC prescription was observed from early 2011 , when limited marketing preceded the availability of NOAC drugs , followed by an accentuated increase due to NOAC prescription accompanied by a plateau in VKA prescription . It is quite likely that at this time point , the availability and marketing of NOACs played a dominant role , with this influence increasing as additional NOACs became available . The final increase from 2013 to 2106 is probably a combination of all three factors : an effective national QOF quality framework , gradual percolation of guidelines and up date s , and continued marketing of NOACs . Ensuring that a high proportion of patients with AF are taking effective doses of OAC rather than aspirin requires first that OAC is offered by the physician and accepted by the patient , secondly that patients are adherent to taking the drugs as prescribed , achieving > 70 % time in the therapeutic international normalized ratio ( INR ) range for VKAs , and finally , that patients persist with taking  OAC therapy long-term . There is a high non-persistence rate for OAC in the first 2 years after initiation , significantly greater for VKAs than
target: Pooled yield of screening was greater in males across all age strata .
  Neither the choice of screening methodology or device , the geographical region , nor the screening setting influenced the detection rate of AF .
  The main limitation of this study is there are insufficient data on sociodemographic variables of the population s and possible ascertainment biases to explain the variance in the sample s. CONCLUSIONS People with screen-detected AF are at elevated calculated stroke risk : above age 65 , the majority have a Class-1 OAC recommendation for stroke prevention , and > 70 % have ≥1 additional stroke risk factor other than age/sex .
background: BACKGROUND The precise age distribution and calculated stroke risk of screen-detected atrial fibrillation ( AF ) is not known .
  Therefore , it is not possible to determine the number needed to screen ( NNS ) to identify one treatable new AF case ( NNS-Rx ) ( i.e. , Class-1 oral anticoagulation [ OAC ] treatment recommendation ) in each age stratum .
  If the NNS-Rx is known for each age stratum , precise cost-effectiveness and sensitivity simulations can be performed based on the age distribution of the population /region to be screened .
  Such calculations are required by national authorities and organisations responsible for health system budgets to determine the best age cutoffs for screening programs and decide whether programs of screening should be funded .
  Therefore , we aim ed to determine the exact yield and calculated stroke-risk profile of screen-detected AF and NNS-Rx in 5-year age strata .