Estimated stroke risk, yield, and number needed to screen for atrial fibrillation detected through single time screening: a multicountry patient-level meta-analysis of 141,220 screened individuals

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 aimed to determine the exact yield and calculated stroke-risk profile of screen-detected AF and NNS-Rx in 5-year age strata. METHODS AND FINDINGS: A systematic review of Medline, Pubmed, and Embase was performed (January 2007 to February 2018), and AF-SCREEN international collaboration members were contacted to identify additional studies. Twenty-four eligible studies were identified that performed a single time point screen for AF in a general ambulant population, including people \u3e /=65 years. Authors from eligible studies were invited to collaborate and share patient-level data. Statistical analysis was performed using random effects logistic regression for AF detection rate, and Poisson regression modelling for CHA2DS2-VASc scores. Nineteen studies (14 countries from a mix of low- to middle- and high-income countries) collaborated, with 141,220 participants screened and 1,539 new AF cases. Pooled yield of screening was greater in males across all age strata. The age/sex-adjusted detection rate for screen-detected AF in \u3e /=65-year-olds was 1.44% (95% CI, 1.13%-1.82%) and 0.41% (95% CI, 0.31%-0.53%) for \u3c 65-year-olds. New AF detection rate increased progressively with age from 0.34% ( \u3c 60 years) to 2.73% ( \u3e /=85 years). Neither the choice of screening methodology or device, the geographical region, nor the screening setting influenced the detection rate of AF. Mean CHA2DS2-VASc scores (n = 1,369) increased with age from 1.1 ( \u3c 60 years) to 3.9 ( \u3e /=85 years); 72% of \u3e /=65 years had \u3e /=1 additional stroke risk factor other than age/sex. All new AF \u3e /=75 years and 66% between 65 and 74 years had a Class-1 OAC recommendation. The NNS-Rx is 83 for \u3e /=65 years, 926 for 60-64 years; and 1,089 for \u3c 60 years. The main limitation of this study is there are insufficient data on sociodemographic variables of the populations and possible ascertainment biases to explain the variance in the samples. 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 \u3e 70% have \u3e /=1 additional stroke risk factor other than age/sex. Our data, based on the largest number of screen-detected AF collected to date, show the precise relationship between yield and estimated stroke risk profile with age, and strong dependence for NNS-RX on the age distribution of the population to be screened: essential information for precise cost-effectiveness calculations

Reducing stroke risk in atrial fibrillation: Adherence to guidelines has improved, but patient persistence with anticoagulant therapy remains suboptimal.

Atrial fibrillation (AF) is a significant risk factor for avoidable stroke. Among high-risk patients with AF, stroke risk can be mitigated using oral anticoagulants (OACs), however reduction is largely contingent on physician prescription and patient persistence with OAC therapy. Over the past decade significant advances have occurred, with revisions to clinical practice guidelines relating to management of stroke risk in AF in several countries, and the introduction of non-vitamin K antagonist OACs (NOACs). This paper summarises the evolving body of research examining guideline-based clinician prescription over the past decade, and patient-level factors associated with OAC persistence. The review shows clinicians\u27 management over the past decade has increasingly reflected guideline recommendations, with an increasing proportion of high-risk patients receiving OACs, driven by an upswing in NOACs. However, a treatment gap remains, as 25–35% of high-risk patients still do not receive OAC treatment, with great variation between countries. Reduction in stroke risk directly relates to level of OAC prescription and therapy persistence. Persistence and adherence to OAC thromboprophylaxis remains an ongoing issue, with 2-year persistence as low as 50%, again with wide variation between countries and practice settings. Multiple patient-level factors contribute to poor persistence, in addition to concerns about bleeding. Considered review of individual patient\u27s factors and circumstances will assist clinicians to implement appropriate strategies to address poor persistence. This review highlights the interplay of both clinician\u27s awareness of guideline recommendations and understanding of individual patient-level factors which impact adherence and persistence, which are required to reduce the incidence of preventable stroke attributable to AF

Uptake of a primary care atrial fibrillation screening program (AF-SMART): a realist evaluation of implementation in metropolitan and rural general practice

Background Screening for atrial fibrillation (AF) in people aged ≥65 years is recommended by international guidelines. The Atrial Fibrillation Screen, Management And guideline-Recommended Therapy (AF-SMART) studies of opportunistic AF screening in 16 metropolitan and rural general practices were conducted from November 2016 - June 2019. These studies trialled custom-designed eHealth tools to support all stages of AF screening in general practice. MethodsA realist evaluation of the AF-SMART studies, which aimed to explain the circumstances in which the program worked (or not) to increase the proportion of people screened for AF. The initial program theory was based on our previous research, policy documents and screening studies. To test this, we conducted 45 semi-structured interviews with general practitioners (GPs), nurses and practice managers across all participating practices, and collected observational and quantitative screening data. These data were analysed and interpreted to refine the program theory.Results GPs/nurses liked the eHealth tools, although technical problems sometimes disrupted screening. Time was the main barrier to screening for GPs/nurses, so systems need to be very efficient. Practices with leadership from a senior GP ‘screening champion’ had broader uptake, especially from the nursing team. Providing regular feedback on screening data was beneficial for quality improvement and motivation. Clear protocols for follow-up of abnormal results were required for successful nurse-led screening in a hierarchical system. Participation in the program had broader benefits of improving AF knowledge and raising the profile of cardiovascular health in the practice. Screening for a shorter, more intense period (eg during influenza vaccination) worked well for practices where sufficient staff time was allocated.ConclusionsIntroducing an AF screening program is likely to be successful in contexts where there is a senior GP ‘screening champion’, a clear protocol exists for abnormal results, and there is regular data reporting to staff. These contexts link to mechanisms around motivation, leadership, empowerment of nurses, and efficient screening systems. The contexts and mechanisms contribute to the longer-term outcomes of increasing the proportion of people screened and treated for AF, which is recommended by guidelines as a key strategy for the prevention of AF-related stroke

Screening education and recognition in community pHarmacies of atrial fibrillation to prevent stroke in an ambulant population aged ?65?years (SEARCH-AF stroke prevention study): a cross-sectional study protocol

Background Atrial fibrillation (AF) is associated with a high risk of stroke and may often be asymptomatic. AF is commonly undiagnosed until patients present with sequelae, such as heart failure and stroke. Stroke secondary to AF is highly preventable with the use of appropriate thromboprophylaxis. Therefore, early identification and appropriate evidence-based management of AF could lead to subsequent stroke prevention. This study aims to determine the feasibility and impact of a community pharmacy-based screening programme focused on identifying undiagnosed AF in people aged 65?years and older. Methods and analysis This cross-sectional study of community-based screening to identify undiagnosed AF will evaluate the feasibility of screening for AF using a pulse palpation and handheld single-lead electrocardiograph (ECG) device. 10 community pharmacies will be recruited and trained to implement the screening protocol, targeting a total of 1000 participants. The primary outcome is the proportion of people newly identified with AF at the completion of the screening programme. Secondary outcomes include level of agreement between the pharmacist's and the cardiologist's interpretation of the single-lead ECG; level of agreement between irregular rhythm identified with pulse palpation and with the single-lead ECG. Process outcomes related to sustainability of the screening programme beyond the trial setting, pharmacist knowledge of AF and rate of uptake of referral to full ECG evaluation and cardiology review will also be collected

In a large primary care data set, the CHA₂DS₂-VASc score leads to an almost universal recommendation for anticoagulation treatment in those aged ≥65 years with atrial fibrillation

From 2012 to 2016, the oral anticoagulant (OAC) treatment determination for atrial fibrillation (AF) patients moved from the CHADS2 score to the CHA2DS2-VASc score. A data set collated during previous studies (2011–19) with de-identified data extracted from clinical records at a single timepoint for active adult patients (n = 285 635; 8294 with AF) attending 164 general practices in Australia was analysed. The CHA2DS2-VASc threshold (score ≥2 men/≥3 women) captured a significantly higher proportion than CHADS2≥2 (all ages: 85 vs. 68%, P < 0.0001; ≥65 years: 96 vs. 76%, P < 0.0001). The change from CHADS2 to CHA2DS2-VASc resulted in a significantly higher proportion of AF patients being recommended OAC, driven by the revised scoring for age

Atrial Fibrillation Screen, Management And Guideline Recommended Therapy (AF SMART II) in the rural primary care setting: a cross-sectional study and cost-effectiveness analysis of eHealth tools to support all stages of screening

BackgroundInternationally, most atrial fibrillation (AF) management guidelines recommend opportunistic screening for AF in people aged ≥65 years, and oral anticoagulant (OAC) treatment for those at high stroke risk (CHA₂DS₂-VA ≥2). However, gaps remain in screening and treatment.Methods and ResultsGeneral practitioners/nurses at practices in rural Australia(n=8) screened eligible patients (aged ≥65 years without AF) using a smartphone electrocardiogram during practice visits. eHealth tools included electronic prompts, guideline-based electronic decision support, and regular data reports. Clinical audit tools extracted deidentified data. Results were compared to an earlier study in metropolitan practices(n=8) and non-randomised control practices(n=69). Cost-effectiveness analysis compared population-based screening to no screening and included screening, treatment and hospitalisation costs for stroke and serious bleeding events. Patients (n=3,103, 34%) were screened (mean age 75.1±6.8 years, 47% male) and 36(1.2%) new AF cases were confirmed (mean age 77.0 years, 64% male, mean CHA₂DS₂-VA=3.2). OAC treatment rates for patients with CHA₂DS₂-VA≥2 were 82% (screen-detected) versus 74% (pre-existing AF)(p=NS), similar to metropolitan and non-randomised control practices. The incremental cost-effectiveness ratio (ICER) for population-based screening was AU$16,578/quality adjusted life year gained and AU$84,383/stroke prevented compared to no screening. National implementation would prevent 147 strokes/year. Increasing the proportion screened to 75% would prevent 177 additional strokes/year.ConclusionsAn AF screening program in rural practices, supported by eHealth tools, screened 34% of eligible patients and was cost-effective. OAC treatment rates were relatively high at baseline, trending upwards during the study. Increasing the proportion screened would prevent many more strokes with minimal ICER change. eHealth tools, including data reports, may be a valuable addition to future programs

Atrial Fibrillation Screen, Management And Guideline Recommended Therapy (AF SMART II) in the rural primary care setting: an implementation study protocol

Introduction: Screening for atrial fibrillation (AF) in people ≥65 years is now recommended by guidelines and expert consensus. While AF is often asymptomatic, it is the most common heart arrhythmia and is associated with increased risk of stroke. Early identification and treatment with oral anticoagulants can substantially reduce stroke risk. The general practice setting is ideal for opportunistic screening and provides a natural pathway for treatment for those identified.This study aims to investigate the feasibility of implementing screening for AF in rural general practice using novel electronic tools. It will assess whether screening will fit within an existing workflow to quickly and accurately identify AF, and will potentially inform a generalisable, scalable approach.Methods and analysis: Screening with a smartphone ECG will be conducted by general practitioners and practice nurses in rural general practices in New South Wales, Australia for 3–4 months during 2018–2019. Up to 10 practices will be recruited, and we aim to screen 2000 patients aged ≥65 years. Practices will be given an electronic screening prompt and electronic decision support to guide evidence-based treatment for those with AF. De-identified data will be collected using a clinical audit tool and qualitative interviews will be conducted with selected practice staff. A process evaluation and cost-effectiveness analysis will also be undertaken. Outcomes include implementation success (proportion of eligible patients screened, fidelity to protocol), proportion of people screened identified with new AF and rates of treatment with anticoagulants and antiplatelets at baseline and completion. Results will be compared against an earlier metropolitan study and a ‘control’ dataset of practices.Ethics and dissemination Ethics approval was received from the University of Sydney Human Research Ethics Committee on 27 February 2018 (Project no.: 2017/1017). Results will be disseminated through various forums, including peer-reviewed publication and conference presentations.Trial registration number ACTRN12618000004268; Pre-results

Estimated stroke risk, yield, and number needed to screen for atrial fibrillation detected through single time screening: a multicountry patient-level meta-analysis of 141,220 screened individuals

BackgroundThe 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 aimed to determine the exact yield and calculated stroke-risk profile of screen-detected AF and NNS-Rx in 5-year age strata.Methods and findingsA systematic review of Medline, Pubmed, and Embase was performed (January 2007 to February 2018), and AF-SCREEN international collaboration members were contacted to identify additional studies. Twenty-four eligible studies were identified that performed a single time point screen for AF in a general ambulant population, including people ≥65 years. Authors from eligible studies were invited to collaborate and share patient-level data. Statistical analysis was performed using random effects logistic regression for AF detection rate, and Poisson regression modelling for CHA2DS2-VASc scores. Nineteen studies (14 countries from a mix of low- to middle- and high-income countries) collaborated, with 141,220 participants screened and 1,539 new AF cases. Pooled yield of screening was greater in males across all age strata. The age/sex-adjusted detection rate for screen-detected AF in ≥65-year-olds was 1.44% (95% CI, 1.13%–1.82%) and 0.41% (95% CI, 0.31%–0.53%) for &lt;65-year-olds. New AF detection rate increased progressively with age from 0.34% (&lt;60 years) to 2.73% (≥85 years). Neither the choice of screening methodology or device, the geographical region, nor the screening setting influenced the detection rate of AF. Mean CHA2DS2-VASc scores (n = 1,369) increased with age from 1.1 (&lt;60 years) to 3.9 (≥85 years); 72% of ≥65 years had ≥1 additional stroke risk factor other than age/sex. All new AF ≥75 years and 66% between 65 and 74 years had a Class-1 OAC recommendation. The NNS-Rx is 83 for ≥65 years, 926 for 60–64 years; and 1,089 for &lt;60 years. The main limitation of this study is there are insufficient data on sociodemographic variables of the populations and possible ascertainment biases to explain the variance in the samples.ConclusionsPeople 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 &gt;70% have ≥1 additional stroke risk factor other than age/sex. Our data, based on the largest number of screen-detected AF collected to date, show the precise relationship between yield and estimated stroke risk profile with age, and strong dependence for NNS-RX on the age distribution of the population to be screened: essential information for precise cost-effectiveness calculations

Stroke prevention in atrial fibrillation through screening and lifestyle interventions

The stroke and health burden associated with atrial fibrillation (AF) is significant and likely to escalate. This burden could be markedly reduced through early identification of AF, and through appropriate management. This thesis aimed to explore the feasibility of community based screening to identify AF, and the effect of risk factor reduction once AF is identified. Firstly, the prevalence of undiagnosed AF identified in community screening was determined through a systematic literature review. Subsequently, a simple AF screening program using innovative smartphone ECG technology was performed in ten community pharmacies in Sydney, Australia. Feasibility and cost effectiveness was evaluated, including qualitative analysis of barriers and enablers to implementation. Additionally, the effect of risk factor management programs was determined by performing a systematic literature review. Finally, the feasibility of a simple brief risk factor management program for people with AF was evaluated. Community screening for AF ≥65 years identifies 1.4% with previously unknown AF, of whom the majority are asymptomatic and at sufficient stroke risk to be eligible for oral anticoagulation for stroke prevention. Screening within community pharmacies, using a handheld ECG, is feasible and cost-effective for stroke prevention, and is warranted as an additional measure to current practice, however a sustainable source of funding is required. Engagement with third party payers is necessary to determine an appropriate funding model. Further research is required to identify a way in which screening can be optimally incorporated into pharmacy workflow. Once AF is identified, lifestyle interventions to address modifiable risk factors in people with AF show great potential for reducing the burden of AF and associated morbidities. Robust randomised controlled trials of novel approaches are needed to identify a suitable and sustainable model of care for delivery of lifestyle interventions