Smartphone and other wearable screening devices detected atrial arrhythmia in five per cent of participants in a study by the Atrial Fibrillation Network (Afnet).

The study offered smartphone- and wearable-based continuous arrhythmia screening to older adults and detected atrial arrhythmia in five per cent of the participants. The results of the study performed by Afnet were published in the European Heart Journal of Digital Health.

Atrial fibrillation (AF) is the most common arrhythmia and a rising epidemic. It affects several million people in Europe. In many people, the arrhythmia is asymptomatic and often remains unnoticed for a long time. However, risk of stroke and other complications may be elevated in older adults with atrial arrhythmias.

Detection of atrial arrhythmias by screening potentially enables earlier therapy to prevent complications, for example by starting anticoagulation to prevent strokes.

The study offered continuous atrial arrhythmia screening to unselected people aged over 65 years without known atrial fibrillation and not receiving oral anticoagulation. The principal investigator Larissa Fabritz, a professor at the University Medical Center Hamburg Eppendorf (UKE), Germany, and the University of Birmingham in the UK, explained the background of the study.

“Simple, scalable methods to identify atrial arrhythmias in at-risk populations are needed to enable timely detection of AF and initiation of therapy,” she said. “To address this societal need, we performed the study and evaluated the usability of a fully digital detection system for atrial arrhythmias in unselected older European adults.”

The study was performed in Germany, Poland and Spain during the Covid-19 pandemic. Between February 2021 and January 2022, 882 citizens aged between 65 and 90 years recorded signals. Their mean age was 71 ±5 years. Of these, 500 (57%) were women, 414 (47%) had high blood pressure, and 97 (11%) diabetes.

Senior citizens were invited to participate in various ways. Most participants (72%) were reached by media campaigns in newspapers and television or by word of mouth and town hall meetings for senior citizens. The remaining participants were attracted by leaflets (11%), identified by general practitioners made aware of the study (9%), a web site (4%), outpatient clinics (2%) or pharmacies (2%).

Participants received a wristband with a photo plethysmography (PPG) sensor to detect the pulse coupled to an app on their smartphone, enabling fully remote continuous rhythm monitoring for up to eight weeks. Over half of the participants (53%) participated without any in-person contact, while 47% of participants received personal assistance with the device.

During the first four weeks, participants transmitted PPG signals for 533 hours, 77% of the maximal observation time of 696 hours. Atrial arrhythmia was detected in 44 participants (5%) within 28 days, and in 53 (6%) within eight weeks. Atrial arrhythmia detection was higher in the first week of monitoring (incidence rate 3.4% in week one) compared with the subsequent weeks (incidence rate 0.55% in weeks two to four).

Fabritz said the study successfully used a smartphone and wearable-based system to detect atrial arrhythmias in older people in several European countries.

“Offers of remote technical assistance were accepted and compliance was high, showing feasibility for this age group,” she said. “Our screening identified atrial arrhythmias in five per cent of older adults. Detection rates were high in the first week of monitoring, and tapered off thereafter, suggesting that relatively short monitoring periods may be sufficient to detect older adults with atrial arrhythmias. These findings encourage the use of fully digital, consumer-electronics based systems to screen for atrial arrhythmias in unselected older adults.”

The investigator-initiated study was initiated and conducted by Afnet. Financial support was provided by Daiichi-Sankyo and in-kind support by Preventicus.

Afnet is an interdisciplinary research network comprising scientists and physicians from hospitals and practices dedicated to improving the management of atrial fibrillation through coordinated research in Germany, Europe and worldwide. Its main objective is to conduct investigator-initiated clinical trials and registries on a national and international level. Long-term activities of the network have been funded by the German Federal Ministry of Research & Education for over a decade. Since January 2015, specific projects and infrastructures of Afnet have been funded by the German Centre for Cardiovascular Research (DZHK).