Is screening for AF worthwhile? Stroke risk in a screened population from the SAFE 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 the over 65s: (SAFE) [ISRCTN19633732] 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. Cost-Effectiveness of a National Opportunistic Screening Program for Atrial Fibrillation in Ireland. Randomised trial of two approaches to screening for atrial fibrillation in UK general practice. Screening for atrial fibrillation in the community: a multicenter validation trial. Screening versus routine practice in detection of atrial fibrillation in patients aged 65 or over: cluster randomised controlled trial Diagnostic accuracy and yield of screening tests for atrial fibrillation in the family practice setting: a multicentre cohort study. Screening for atrial fibrillation in general practice: a national, cross-sectional study of an innovative technology. Age-dependent yield of screening for undetected atrial fibrillation in stroke patients: the Find-AF study Probing oral anticoagulation in patients with atrial high rate episodes: Rationale and design of the Non–vitamin K antagonist Oral anticoagulants in patients with Atrial High rate episodes (NOAH–AFNET 6) trial Screening for asymptomatic atrial fibrillation while monitoring the blood pressure at home: trial of regular versus irregular pulse for prevention of stroke (TRIPPS 2.0). Performance of stroke risk scores in older people with atrial fibrillation not taking warfarin: comparative cohort study from BAFTA trial Uncovering Atrial Fibrillation Beyond Short-Term Monitoring in Cryptogenic Stroke Patients: Three-Year Results From the Cryptogenic Stroke and Underlying Atrial Fibrillation Trial Major progress in anticoagulant uptake for atrial fibrillation at last: does it translate into stroke prevention? Incidence of chronic atrial fibrillation in general practice and its treatment pattern. Opportunistic screening for atrial fibrillation versus detecting symptomatic patients aged 65 years and older: A cluster-controlled clinical trial.
INTRODUCTION Atrial fibrillation ( AF ) is an important independent risk factor for stroke and oral anticoagulation therapy provides a highly effective treatment to reduce this risk . Active screening strategies improve detection of AF in comparison with routine care ; however , whether screen-detected patients have stroke risk profiles favouring anticoagulation is unclear . Using data derived from the screening for AF in the elderly ( SAFE ) study , the aim of this article was to determine if patients with AF detected via active screening  have stroke risk profiles that warrant prophylactic anticoagulation . METHODS Secondary analysis of data derived from 25 general practice s within which cohorts of 200 patients were r and omly allocated to opportunistic [ pulse and electrocardiogram ( ECG ) ] or systematic screening ( postal invitation for ECG ) .  Stroke risk assessment was undertaken using baseline data extracted from medical records and CHADS2 criteria . CHADS2 scores were compared between the screening groups . RESULTS One hundred and forty-nine new cases of AF were detected , 75 via opportunistic screening and 74 via systematic screening . CHADS2 scores were ≥1 in 83 % [ 95 % confidence interval ( CI ) 72.6 - 89.6 ] of patients detected via opportunistic screening and 78 % ( 95 % CI 67.7 - 86.2 ) detected via systematic screening . There were no significant differences in stroke risk profiles of patients detected via opportunistic and systematic screenings . CONCLUSION Stroke risk profiles of patients detected via opportunistic and systematic screenings were similar . Data derived from the SAFE study suggest that active screening for AF in patients aged ≥65 years in primary care is a useful screening programme with 78 - 83 % of patients identified eligible for anticoagulation treatment according to the CHADS2 criteria Background Atrial fibrillation ( AF ) has been recognised as an important independent risk factor for thromboembolic disease , particularly stroke for which it provides a five-fold increase in risk . This study aim ed to determine the baseline prevalence and the incidence of AF based on a variety of screening strategies and in doing so to evaluate the incremental cost-effectiveness of different screening strategies , including targeted or whole population screening , compared with routine clinical practice , for detection of AF in people aged 65 and over . The value of clinical assessment and echocardiography as additional methods of risk stratification for thromboembolic disease in patients with AF were also evaluated . Methods The study design was a multi-centre r and omised controlled trial with a study population of patients aged 65 and over from 50 General Practice s in the West Midl and s. These purpose fully selected general practice s were r and omly allocated to 25 intervention practice s and 25 control practice s. GPs and practice nurses within 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 high risk targeted screening and total population screening . AF detection rates in systematic ally screened and opportunistically screened population s in the intervention practice s were compared to AF detection rate in 5,000 patients in the control practice 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 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 BACKGROUND Atrial fibrillation is a common and treatable cause of stroke that often remains unrecognised . Screening has been suggested but there is very little evidence concerning the uptake of screening in the elderly population at risk , nor of the optimal method of screening in a general practice setting AIM To compare the uptake and effectiveness of two methods of screening for atrial fibrillation in general practice -- systematic nurse-led screening and prompted opportunistic case finding . DESIGN OF STUDY R and omised controlled trial . SETTING Patients aged 65 to 100 years ( n = 3,001 ) from four general practice s within the MRC general practice framework . METHOD Each of the four study practice s were selected from one quartile , after ranking all framework practice s according to the small area st and ardised mortality ratio of the geographical area served . Patients were r and omised either to nurse-led screening or to prompted opportunistic casefinding . The proportion of patients assessed and the proportion found to have atrial fibrillation were compared . The sensitivity and specificity of clinical assessment of pulse are also reported . RESULTS Substantially more patients had their pulse assessed through systematic screening by invitation ( 1,099/1,499 [ 73 % ] ) than through opportunistic case finding ( 439/1,502 [ 29 % ] , difference = 44 % , 95 % confidence interval [ CI ] = 41 % to 47 % ) . Atrial fibrillation was detected in 67 ( 4.5 % ) and 19 ( 1.3 % ) patients respectively ( difference = 3.2 % , 95 % CI= 2.0 to 4.4 ) . Invitation to nurse-led screening achieved significantly higher assessment rates than case finding in all practice s ; however , the proportion of patients assessed in the case-finding arm varied markedly between practice s ( range = 8 % to 52 % ) . The number needed to screen to identify one additional patient with atrial fibrillation was 31 ( 95 % CI = 23 to 50 ) . The proportion of screened patients with atrial fibrillation receiving anticoagulation treatment was 25 % , although in the majority ( 53/65 [ 82 % ] ) atrial fibrillation had been previously recorded somewhere on their medical record . If the nurse used any irregularity of the pulse as the screening criterion , the sensitivity of screening was 91 % and the specificity was 74 % ; sensitivity fell to 54 % but specificity increased to 98 % if the criterion used was continuous irregularity . CONCLUSIONS Nurse-led screening for atrial fibrillation in UK general practice is both feasible and effective and will identify a substantial number of patients who could benefit from antithrombotic therapy . Although the majority of patients detected at first screening could be identified by careful scrutiny of medical records , review of record summaries was insufficient in the practice s involved in this study and screening may be a more cost-effective option BACKGROUND Atrial fibrillation ( AF ) is an important public health problem . This arrhythmia is common and associated with a high risk of stroke . Further , appropriate interventions in AF can reduce the risk of stroke by approximately 68 % . Population studies show that a large group of patients have intermittent or chronic AF that remains unrecognized . If a simple screening test for this arrhythmia could be developed and vali date d , application of the technique across population s might identify AF patients for early treatment , potentially reducing the incidence of stroke . In this study , we sought to determine whether individuals taken from the general community could be taught to find and classify the pulse of another as very irregular , implying AF , or regular , implying normal sinus rhythm ( NSR ) . The aim was to establish that pulse examination for potential AF could be performed by individuals with sufficient sensitivity and specificity to be effectively used as a screening procedure for this medically important arrhythmia . METHODS We enrolled 178 subjects selected from the general community from four centers . Subjects received st and ardized education on the medical importance of AF and its signature , a very irregular pulse . A technique for palpating and characterizing the rhythm of the radial pulse was also taught . Without further coaching , subjects were then asked to find their pulse and then to find and classify the pulse of two models r and omly presented who may or may not have had AF . RESULTS Of the 178 subjects tested , 92 % were able to find their own pulse ; 17 ( 9.6 % ) were unable to find the pulse of one or both patient models and were , therefore , excluded from the study . Of the remaining 161 subjects , 76 % ( 122 of 161 ) correctly identified the pulse in an AF model , and 86 % ( 139 of 161 ) correctly identified the pulse in an NSR model . Results did not statistically differ as a function of age , educational status , or location . DISCUSSION This multicenter trial established that given minimal st and ardized instructions , subjects from the general community can reliably and consistently find both their pulse as well as the pulse of another and to differentiate a regular pulse from a very irregular pulse . If similar educational programs were widely applied across large population s , periodic screening for AF might lead to earlier diagnosis and appropriate treatment for patients who have this major risk factor for stroke . These screening programs should be focused on the population over the age of 55 where the risk of stroke in AF increases with each decade 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 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 BACKGROUND To test the use of three lead monitoring as a screening tool for  atrial fibrillation ( AF )  in general practice . AF is responsible for up to a quarter of all strokes and is often asymptomatic until a stroke occurs . METHODS 26 r and omly selected general practice s identified 80 r and omly selected patients aged 70 or older from their data base and excluded those known to have AF , those with clinical issues or who had not attended for three years . Up to 40 eligible patients / practice were invited to attend for screening . A 2min three-lead ECG was recorded and collected central ly for expert cardiology assessment . Risk factor data was gathered . OUTCOMES ( i ) point prevalence of AF , ( ii ) proportion of ECG tracings which were adequate for interpretation , ( iii ) uptake rate by patients and ( iv ) acceptability of the screening process to patients and staff ( reported separately ) . RESULTS Of 1447 current patients , 1003 were eligible for inclusion , 639 ( 64 % ) agreed to take part in screening and 566 ( 56 % ) completed screening . The point prevalence rate for AF was 10.3%-2.1 % new cases ( 12 of 566 who were screened ) and 9.5 % existing cases ( 137 of 1447 eligible patients ) . Only four of 570 ( 0.7 % ) screening visits did not record a usable ECG and 11 ( 2.6 % ) three lead ECGs required a clarifying 12 lead ECG . CONCLUSIONS Three lead screening for AF is feasible , effective and offers an alternative to pulse taking or 12 lead ECGs . The availability of this technology may facilitate more effective screening , leading to reduced stroke incidence Diagnosis of paroxysmal atrial fibrillation ( AF ) in stroke patients is challenging , but highly clinical ly relevant . The percentage of stroke patients with permanent AF  increases with age , but limited data are available for the age-dependent yield of paroxysmal AF by Holter monitoring . Patients with acute cerebral ischemia were included into the prospect i ve observational Find-AF study . Patients free from AF at presentation received 7 day Holter monitoring .  We calculated the percentage of otherwise undetected paroxysmal AF and the number needed to screen for age groups under 60 years , and in 5 year clusters from the age of 60 up to 85 and older . 272 patients were included , 43 ( 15.8 % ) had AF at admission , 33 patients with paroxysmal AF were identified by 7 day Holter ( n = 29 ) or medical history ( n = 4).The yield of 7 day Holter ECG  clearly increased with older age ( p = 0.004 ) : < 60 years : 5 % , 60–64 years : 5 % , 65–69 years : 7 % , 70–74 years : 11 % , 75–79 years : 13 % , 80–84 years : 25 % , ≥85 years : 39 % . The number needed to screen ( NNS ) to find one patient with paroxysmal AF decreased with age : ≤60 years : 18 , 60–64 years : 20 , 65–69 years : 14 , 70–74 years : 9 , 75–79 years : 8 , 80–84 years : 4 , ≥85 years : 3 , respectively . In patients < 65 years , all AF cases were detected by Holter ECG . The percentage of paroxysmal AF in stroke patients increases with age . The  7 day Holter ECG  is most efficient in elderly patients Background Oral anticoagulation prevents ischemic strokes in patients with atrial fibrillation ( AF ) . Early detection of AF and subsequent initiation of oral anticoagulation help to prevent strokes in AF patients . Implanted cardiac pacemakers and defibrillators allow seamless detection of atrial high rate episodes ( AHRE ) , but the best antithrombotic therapy in patients with AHRE is not known . Rationale Stroke risk is higher in pacemaker patients with AHRE than in those without , but the available data also show that stroke risk in patients with AHRE is lower than in patients with AF . Furthermore , only a minority of patients with AHRE will develop AF , many strokes occur without a temporal relation to AHRE , and AHRE can reflect other arrhythmias than AF or artifacts . An adequately powered controlled trial of oral anticoagulation in patients with AHRE is needed . Design The Non – vitamin K antagonist Oral anticoagulants in patients with Atrial High rate episodes ( NOAH – AFNET 6 ) trial tests whether oral anticoagulation with edoxaban is superior to prevent the primary efficacy outcome of stroke or cardiovascular death compared with aspirin or no antithrombotic therapy based on evidence ‐based indications . The primary safety outcome will be major bleeding . NOAH – AFNET 6 will r and omize 3,400 patients with AHRE , but without documented AF , aged ≥65 years with at least 1 other stroke risk factor , to oral anticoagulation therapy ( edoxaban ) or no anticoagulation . All patients will be followed until the end of this investigator‐driven , prospect i ve , parallel‐group , r and omized , event‐driven , double‐blind , multicenter phase IIIb trial . Patients will be censored when they develop AF and offered open‐label anticoagulation . The sponsor is the Atrial Fibrillation NETwork ( AFNET ) . The trial is supported by the DZHK ( German Centre for Cardiovascular Research ) , the BMBF ( German Ministry of Education and Research ) , and Daiichi Sankyo Europe . Conclusion NOAH – AFNET 6 will provide robust information on the effect of oral anticoagulation in patients with atrial high rate episodes detected by implanted devices . Graphical abstract Figure . No Caption available Asymptomatic atrial fibrillation ( AF ) is a common cause of strokes . Physician screening for AF has been recommended . Home screening for AF may increase the likelihood of detecting asymptomatic AF in patients at risk for stroke because of AF . The aim of this study was to assess the feasibility and accuracy of screening for AF when taking home blood pressure ( BP ) measurements using an automatic AF-detecting BP monitor .  Subjects aged > 64 years or those with hypertension , diabetes , congestive heart failure , or previous stroke were enrolled by their primary physicians and given the AF-BP monitor and an electrocardiographic event monitor to use at home for 30 days . The AF-BP monitor reading was compared with the electrocardiographic reading to calculate the sensitivity and specificity of the device for detecting AF . A total of 160 subjects were enrolled , with 10 withdrawing , 1 excluded , and 10 with no AF-BP monitor logs or electrocardiographic recordings . Of the 139 subjects included , 14 had known AF . There was a total of 3,316 days with AF-BP monitor readings and electrocardiographic readings . On the basis of the initial daily AF-BP monitor readings , the AF-BP monitor demonstrated sensitivity of 99.2 % and specificity of 92.9 % for detecting AF . Two subjects with no histories of AF had AF-BP monitor readings of AF that were confirmed by the electrocardiographic monitor . One of these subjects was started on warfarin . In conclusion , home screening for asymptomatic AF while taking BP measurements can be performed accurately . This can be used to detect new AF , allowing treatment with anticoagulation to reduce the future risk for stroke Objective To compare the predictive power of the main existing and recently proposed schemes for stratification of risk of stroke in older patients with atrial fibrillation . Design Comparative cohort study of eight risk stratification scores . Setting Trial of thromboprophylaxis in stroke , the Birmingham Atrial Fibrillation in the Aged ( BAFTA ) trial . Participants 665 patients aged 75 or over with atrial fibrillation based in the community who were r and omised to the BAFTA trial and were not taking warfarin throughout or for part of the study period . Main outcome measures Events rates of stroke and thromboembolism . Results 54 ( 8 % ) patients had an ischaemic stroke , four ( 0.6 % ) had a systemic embolism , and 13 ( 2 % ) had a transient ischaemic attack . The distribution of patients classified into the three risk categories ( low , moderate , high ) was similar across three of the risk stratification scores ( revised CHADS2 , NICE , ACC/AHA/ESC ) , with most patients categorised as high risk ( 65 - 69 % , n=460 - 457 ) and the remaining classified as moderate risk . The original CHADS2 ( Congestive heart failure , Hypertension , Age ≥75 years , Diabetes , previous Stroke ) score identified the lowest number as high risk ( 27 % , n=180 ) . The incremental risk scores of CHADS2 , Rietbrock modified CHADS2 , and CHA2DS2-VASc ( CHA2DS2-Vascular disease , Age 65 - 74 years , Sex ) failed to show an increase in risk at the upper range of scores . The predictive accuracy was similar across the tested schemes with C statistic ranging from 0.55 ( original CHADS2 ) to 0.62 ( Rietbrock modified CHADS2 ) , with all except the original CHADS2 predicting better than chance . Bootstrapped paired comparisons provided no evidence of significant differences between the discriminatory ability of the schemes . Conclusions Based on this single trial population , current risk stratification schemes in older people with atrial fibrillation have only limited ability to predict the risk of stroke . Given the systematic undertreatment of older people with anticoagulation , and the relative safety of warfarin versus aspirin in those aged over 70 , there could be a pragmatic rationale for classifying all patients over 75 as “ high risk ” until better tools are available Background —Atrial fibrillation ( AF ) can be a cause of previously diagnosed cryptogenic stroke . However , AF can be paroxysmal and asymptomatic , thereby making detection with routine ECG methods difficult . Oral anticoagulation is highly effective in reducing recurrent stroke in patients with AF , but its initiation is dependent on the detection of AF . Cryptogenic Stroke and Underlying Atrial Fibrillation ( CRYSTAL AF ) is the first r and omized study to report the detection of AF in cryptogenic stroke patients using continuous long-term monitoring via insertable cardiac monitors ( ICM ) . Methods and Results — Patients with prior cryptogenic stroke were r and omized to control ( n=220 ) or ICM ( n=221 ) and followed for ⩽36 months . Cumulative AF detection rates in the ICM arm increased progressively during this period ( 3.7 % , 8.9 % , 12.4 % , and 30.0 % at 1 , 6 , 12 , and 36 months , respectively ) , but remained low in the control arm ( 3.0 % at 36 months ) . This result ed in oral anticoagulation prescription in 94.7 % of ICM patients with AF detected at 6 months , 96.6 % at 12 months , and 90.5 % at 36 months . Among ICM patients with AF detected , the median time to AF detection was 8.4 months , 81.0 % of first AF episodes were asymptomatic , and 94.9 % had at least 1 day with > 6 minutes of AF . Conclusions —Three-year monitoring by ICM in cryptogenic stroke patients demonstrated a significantly higher AF detection rate compared with routine care . Given the frequency of asymptomatic first episodes and the long median time to detection , these findings highlight the limitations of using traditional AF detection methods . The majority of patients with AF were prescribed oral anticoagulation therapy . Clinical Trial Registration — Clinical trials.gov ; Unique identifier : NCT00924638 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 The object of this article was to estimate the incidence rate of chronic atrial fibrillation ( AF )  in a general practice setting , to identify factors predisposing to its occurrence , and to describe treatment patterns in the year following the diagnosis . The method used was a population -based cohort study using the General Practice Research Data base ( GPRD ) in the UK . We identified patients aged 40 - 89 years with a first ever recorded diagnosis of AF . The diagnosis was vali date d through a question naire sent to the general practitioners . A nested case-control analysis was performed to assess risk factors for AF using 1,035 confirmed incident cases of chronic AF and a r and om sample of 5,000 controls from the original source population . The incidence rate of chronic AF was 1.7 per 1,000 person-years , and increased markedly with age . The age adjusted rate ratio among males was 1.4 ( 95 % CI 1.2 - 1.6 ) . The major risk factors were age , high BMI , excessive alcohol consumption , and prior cardiovascular comorbidity , in particular , valvular heart disease and heart failure . Digoxin was used in close to 70 % of the patients , and close to 15 % did not receive any antiarrhythmic treatment . Close to 40 % did not receive either warfarin or aspirin in the 3 months period after the diagnosis . Among the potential c and i date s for anticoagulation only 22 % of those aged 70 years or older were prescribed warfarin in comparison to 49 % among patients aged 40 - 69 years . Chronic AF is a disease of the elderly , with women presenting a lower incidence rate than men specially in young age . Age , weight , excessive alcohol consumption , and cardiovascular morbidity were the main independent risk factors for AF . Less than half of patients with chronic AF and no contraindications for anticoagulation received warfarin within the first trimester after the diagnosis 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 )
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 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 .