Hot Line - Can smartphones improve AF detection in older adults?

The potential to use smart devices for large-scale screening of atrial fibrillation (AF) has already been demonstrated.^1,2 However, the utility of this approach among older individuals – a relevant target population but one for whom digital technologies may be challenging – and its direct comparison with standard screening strategies has not been investigated. 

In a Hot Line session yesterday, Professor Axel Bauer (Innsbruck Medical University - Innsbruck, Austria) presented findings from the eBRAVE-AF trial in older adults at risk of stroke, which compared the use of ordinary smartphones with conventional screening to detect AF that was then treated with oral anticoagulation.

In this siteless, open-label trial, participants were policyholders with a German healthcare insurance company who were aged 50 to 90 years, owned a smartphone, had no known AF, no prescription of oral anticoagulants and had a CHA₂DS₂-VASc score ≥1 for men or ≥2 for women. A dedicated study app was used for randomisation, for self-screening and, in combination with telephone calls, for communication between participants and researchers. Participants were randomly assigned 1:1 to 6 months of either digital screening or standard real-world screening, including, for example, use of symptoms and routine ECG screening. Digital screening involved repetitive phone-based one-minute photoplethysmographic (PPG) pulse wave self-measurements twice a day for 14 days then twice a week thereafter. In the event of abnormal results, participants received a patch to record a 14-day ECG, which was then evaluated by researchers. Results were sent directly to participants with instructions to contact their local physician, who was independently responsible for the subsequent treatment decision.

The primary efficacy endpoint was newly diagnosed AF within the first 6 months, leading to oral anticoagulation initiation by the treating physician. Participants not reaching the primary endpoint were able to participate in a second 6-month phase, involving crossover to the alternative screening method.

Among 5,551 participants randomised, digital screening doubled the detection of treatment-relevant AF, with rates of 1.33% and 0.63% in the digital and standard screening arms, respectively (odds ratio [OR] 2.12; 95% CI 1.19 to 3.76; p=0.010).

Digital screening was also superior to standard screening in the 4,752 participants taking part in the crossover (OR 2.95; 95% CI 1.52 to 5.72; p=0.001). Major adverse cardiac and cerebrovascular events were predicted by AF (hazard ratio [HR] 6.13; 95% CI 3.07 to 12.21; p<0.001), PPG-detected AF (HR 3.22; 95% CI 1.01 to 10.33; p=0.049) and abnormal PPG findings (HR 2.74; 95% CI 1.25 to 6.00; p=0.012).

According to Professor Bauer, “Screening using common smartphones significantly increased the detection rate of therapy-relevant AF. Digital screening was well received by older participants, who tended to perform even more PPG measurements than younger participants in the study.”