Wearable-based screening identified atrial fibrillation in five percent of older adults
Consumer electronics provide a novel route to screen for atrial arrhythmias. The Smart in OAC – AFNET 9 study offered smartphone and wearable-based continuous arrhythmia screening to older adults and detected atrial arrhythmia in five percent 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 in order to prevent strokes.
The Smart in OAC – AFNET 9 (Smartphone and wearable detected atrial arrhythmia in Older Adults Case finding) 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 of Smart in OAC – AFNET 9, Professor Larissa Fabritz, University Medical Center Hamburg Eppendorf (UKE), Hamburg, Germany and University of Birmingham, 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. To address this societal need, we performed the Smart in OAC – AFNET 9 study and evaluated the usability of a fully digital detection system for atrial arrhythmias in unselected older European adults.” The study design was published in .
Smart in OAC – AFNET 9 was performed in Germany, Poland and Spain during the Covid-19 pandemic. Between 01.02.2021 and 31.01.2022, 882 senior 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, 97 (11%) diabetes.
Senior citizens were invited to participate by various ways. The majority of 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 website (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 1) compared to the subsequent weeks (incidence rate 0.55% in weeks 2-4).
Professor Fabritz concluded: “Smart in OAC – AFNET 9 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. Our screening identified atrial arrhythmias in 5% 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.”
Smart in OAC – AFNET 9 is an investigator-initiated study. It was initiated and conducted by AFNET. Financial support was provided by Daiichi-Sankyo, in-kind support by Preventicus.
 Fabritz L, Connolly DL, Czarnecki E, Dudek D, Guasch E, Haase D, Huebner T, Zlahoda-Huzior A, Jolly K, Kirchhof P, Obergassel J, Schotten U, Vettorazzi E, Winkelmann S, Zapf A, Schnabel RB, for the Smart in OAC - AFNET 9 investigators. Wearable-based detection of atrial arrhythmias in older adults. The fully digital European Smart in OAC – AFNET 9 case finding study. Eur Heart J Digital Health. 22.11.2022. doi:10.1093/ehjdh/ztac067
 Fabritz L, Connolly D, Czarnecki E, Dudek D, Zlahoda-Huzior A, Guasch E, Haase D, Huebner T, Jolly K, Kirchhof P, Schotten U, Zapf A, Schnabel R. Remote Design of a Smartphone and Wearable Detected Arial Arrhythmia in Older Adults Case Finding Study: Smart in OAC - AFNET 9. Front Cardiovasc Med. 21.03.2022. doi:10.3389
About the Atrial Fibrillation NETwork (AFNET)
The Atrial Fibrillation NETwork 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 high quality investigator-initiated clinical trials and registries on a national and international level. The AFNET continues the long-term activities of the network which has been funded by the German Federal Ministry of Research and Education over a decade. Since January 2015, specific projects and infrastructures of the AFNET are funded by the German Centre for Cardiovascular Research (DZHK).
Angelika Leute, PhD
Phone: +49 202 2623395
Fabritz L et al. Wearable-based detection of atrial arrhythmias in older adults. The fully digital European Smart in OAC – AFNET 9 case finding study. Eur Heart J Digital Health. 22.11.2022. doi:10.1093/ehjdh/ztac067