Atrial fibrillation (AF) poses challenges to primary care on a number of fronts.
AF is the most common sustained cardiac arrhythmia and heightens the risk of both developing and dying from cardiovascular disease (CVD).
Not only is it associated with a five-fold increased risk of stroke, with up to 25% of stroke patients presenting with AF, but AF-related strokes are also more severe due to higher mortality and greater disability. One study also found that AF is a direct cause in 5% of congestive heart failure cases, and AF has been established as present in up to 50% of patients with severe heart failure.
Therefore, unsurprisingly, it’s estimated that the total direct medical costs of AF patients are 73% higher than matched control subjects. The cumulative effect is a substantial economic burden on healthcare systems as a whole. In 2020, AF is predicted to have cost the NHS a minimum of £1.435 billion and a maximum of £2.548 billion; that’s between 0.9-1.6% of annual NHS expenditure, on just one condition.
Over the next 2 decades, these costs are predicted to escalate to 1.35-4.27% of NHS expenditure as the prevalence of AF is set to increase dramatically in line with the growth of the most at-risk patient population; those aged over 50. The primary driver of costs is hospitalisations.
In 2019, an estimated 1.6 million people were suffering from AF in the UK. In the past two decades alone, AF’s prevalence increased by 33%, and over the next 30 years it is estimated to become one of the largest epidemics and public health challenges we face.
SO, WHERE DOES PRIMARY CARE COME INTO THIS?
A rise in prevalence is driving a rise in hospitalisations and therefore costs due to the nature of disease progression, which results in low opportunity for diagnosis and intervention within the clinically recognised ‘golden 6 month period’.
This golden 6 month period is the pre-diagnostic and diagnostic stage of the patient journey whereby primary care screening can allow for various forms of prevention;
-
primordial (i.e. preventing risk factors through healthy lifestyle interventions),
-
primary (i.e. preventing onset through risk factor reduction such as weight loss, hypertension and diabetes control), and
-
secondary (i.e. providing an early diagnosis and preventing complications).
Within this first 6 month period, patients will initially enter paroxysmal AF whereby episodes of arrhythmia are self-terminating, last no longer than 7 days, and commonly last less than 24 hours. Due to the transient nature of these episodes, and the fact that between 10-40% of episodes are asymptomatic, paroxysmal AF is very difficult to diagnose and hence opportunities for prevention (as outlined above) are limited.
Without effective prevention, the frequency and severity (in terms of heart rate increase) of AF episodes will progress as patients become more symptomatic and enter persistent AF. In this stage, episodes are not self-terminating, they last more than 7 days, and require pharmaceutical or electrical cardioversion (i.e. rhythm and rate therapies) to terminate. Beyond this, 40% of persistent AF patients will develop permanent AF within one year post-diagnosis, whereby no therapeutic interventions are successful in terminating AF.
The key challenge for primary care is implementing population-wide screening, without which the opportunity to diagnose patients within this golden window is significantly worsened. Anticoagulation can prevent around two-thirds of AF-related strokes, and so overcoming this barrier to diagnosis is vital.
Current means of screening are limited to opportunistic pulse palpations during in-clinic appointments. If AF is suspected during pulse palpation, an electrocardiogram (ECG/EKG) will then be used to confirm diagnosis; either in the form of a 12-lead ECG in a clinical setting or an ambulatory ECG, worn as a holter/event monitor or as a loop recorder implanted under the chest skin, which is more effective in diagnosing paroxysmal AF. More recently, FDA-approved portable ECGs have also become available in the form of KardiaMobile’s AliveCor device.
Regardless, none of these screening methods are accessible enough to facilitate the population-wide screening required to stem the growth of this epidemic and its consequential pressure on our healthcare services. Our primary care services are already overstretched; bringing every member of the public in for pulse palpation is not an option.
Hence, in an effort to ‘find the missing 300,000’ (British Heart Foundation 2019 campaign) people in the UK estimated to be living undiagnosed with AF, the NHS are introducing incentives for primary care clinics around opportunistic AF screening during regular appointments starting in April 2022.
This, in turn, is bolstering innovation which can both support these goals and go one step further, by facilitating early diagnoses on a population-wide scale.
RECENT ADVANCEMENTS
A rise in prevalence is driving a rise in hospitalisations and therefore costs due to the nature of disease progression, which results in low opportunity for diagnosis and intervention within the clinically recognised ‘golden 6 month period’.
This golden 6 month period is the pre-diagnostic and diagnostic stage of the patient journey whereby primary care screening can allow for various forms of prevention;
-
primordial (i.e. preventing risk factors through healthy lifestyle interventions),
-
primary (i.e. preventing onset through risk factor reduction such as weight loss, hypertension and diabetes control), and
-
secondary (i.e. providing an early diagnosis and preventing complications).
Within this first 6 month period, patients will initially enter paroxysmal AF whereby episodes of arrhythmia are self-terminating, last no longer than 7 days, and commonly last less than 24 hours. Due to the transient nature of these episodes, and the fact that between 10-40% of episodes are asymptomatic, paroxysmal AF is very difficult to diagnose and hence opportunities for prevention (as outlined above) are limited.
Without effective prevention, the frequency and severity (in terms of heart rate increase) of AF episodes will progress as patients become more symptomatic and enter persistent AF. In this stage, episodes are not self-terminating, they last more than 7 days, and require pharmaceutical or electrical cardioversion (i.e. rhythm and rate therapies) to terminate. Beyond this, 40% of persistent AF patients will develop permanent AF within one year post-diagnosis, whereby no therapeutic interventions are successful in terminating AF.
The key challenge for primary care is implementing population-wide screening, without which the opportunity to diagnose patients within this golden window is significantly worsened. Anticoagulation can prevent around two-thirds of AF-related strokes, and so overcoming this barrier to diagnosis is vital.
Current means of screening are limited to opportunistic pulse palpations during in-clinic appointments. If AF is suspected during pulse palpation, an electrocardiogram (ECG/EKG) will then be used to confirm diagnosis; either in the form of a 12-lead ECG in a clinical setting or an ambulatory ECG, worn as a holter/event monitor or as a loop recorder implanted under the chest skin, which is more effective in diagnosing paroxysmal AF. More recently, FDA-approved portable ECGs have also become available in the form of KardiaMobile’s AliveCor device.
Regardless, none of these screening methods are accessible enough to facilitate the population-wide screening required to stem the growth of this epidemic and its consequential pressure on our healthcare services. Our primary care services are already overstretched; bringing every member of the public in for pulse palpation is not an option.
Hence, in an effort to ‘find the missing 300,000’ (British Heart Foundation 2019 campaign) people in the UK estimated to be living undiagnosed with AF, the NHS are introducing incentives for primary care clinics around opportunistic AF screening during regular appointments starting in April 2022.
This, in turn, is bolstering innovation which can both support these goals and go one step further, by facilitating early diagnoses on a population-wide scale.
RECENT ADVANCEMENTS
Recent advancements in remote monitoring technologies have applied machine learning algorithms to accurately measure vital signs and other physiological parameters, including heart rhythm and AF detection, from smartphone sensor data alone; without the need for additional devices.
Built into patient-friendly smartphone applications that form a real-time communication channel with care providers, this provides a golden opportunity to enable more timely interventions, improve patient outcomes and streamline primary care workflows, all while lowering overall costs of care.
As Dr David Buckley, GP at Trinity Court Surgery explains, “the drive to improve detection and monitoring of such significant cardiovascular conditions as atrial fibrillation requires us to develop new, user-friendly technologies to improve outcomes for the huge number of undiagnosed patients that remain at risk.”
At electronRx, we are working with primary care leaders in the NHS to develop and fast-track approval of a truly scalable, population-wide screening tool for AF that will deconstruct these barriers to diagnosis and care. Not only will this allow primary care surgeries to satisfy the new NHS incentive scheme, but it will also enable a proactive, preventive approach to both AF diagnosis and management. In doing so, we can stem the epidemic at its source and improve the lives of millions across the globe.
