gms | German Medical Science

49. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie (gmds)
19. Jahrestagung der Schweizerischen Gesellschaft für Medizinische Informatik (SGMI)
Jahrestagung 2004 des Arbeitskreises Medizinische Informatik (ÖAKMI)

Deutsche Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie
Schweizerische Gesellschaft für Medizinische Informatik (SGMI)

26. bis 30.09.2004, Innsbruck/Tirol

Telemedicine meets epidemiology : TeleECG in the Study of Health in Pomerania (SHIP)

Meeting Abstract (gmds2004)

  • corresponding author presenting/speaker Dietrich Alte - Ernst-Moritz-Arndt-Universität Greifswald, Institut für Epidemiologie und Sozialmedizin, Greifswald, Deutschland
  • Henry Völzke - Ernst-Moritz-Arndt-Universität Greifswald, Institut für Epidemiologie und Sozialmedizin, Greifswald, Deutschland
  • Daniel M. Robinson - Ernst-Moritz-Arndt-Universität Greifswald, Institut für Epidemiologie und Sozialmedizin & Klinik für Innere Medizin B, Greifswald, Deutschland
  • Volker Kleine - Ernst-Moritz-Arndt-Universität Greifswald, Institut für Epidemiologie und Sozialmedizin & Klinik für Innere Medizin B, Greifswald, Deutschland
  • Hans Jörgen Grabe - Klinik für Psychiatrie und Psychotherapie der Ernst-Moritz-Arndt-Universität Greifswald im Klinikum der Hansestadt Stralsund, Stralsund, Deutschland
  • Ulrich John - Ernst-Moritz-Arndt-Universität Greifswald, Institut für Epidemiologie und Sozialmedizin, Greifswald, Deutschland
  • Stephan B. Felix - Ernst-Moritz-Arndt-Universität Greifswald, Klinik für Innere Medizin B, Greifswald, Deutschland

Kooperative Versorgung - Vernetzte Forschung - Ubiquitäre Information. 49. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie (gmds), 19. Jahrestagung der Schweizerischen Gesellschaft für Medizinische Informatik (SGMI) und Jahrestagung 2004 des Arbeitskreises Medizinische Informatik (ÖAKMI) der Österreichischen Computer Gesellschaft (OCG) und der Österreichischen Gesellschaft für Biomedizinische Technik (ÖGBMT). Innsbruck, 26.-30.09.2004. Düsseldorf, Köln: German Medical Science; 2004. Doc04gmds022

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/gmds2004/04gmds022.shtml

Veröffentlicht: 14. September 2004

© 2004 Alte et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


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Introduction

Cardiac arrhythmia has been shown to be an important risk factor for sudden coronary death [1], [2], [3] or cardiac mortality [4], [5]. However, there is few information from population-based studies with respect to prevalence and risk factors for cardiac arrhythmias [6]. Especially, intermittent arrhythmias have not been well investigated in that context.

The aim of this paper is to report the first implementation of a portable ECG card in a large population-based epidemiological study. We evaluate the use of ECG cards in our study, and report implementation issues from the ongoing "Study of Health in Pomerania" (SHIP), which includes the long-term aims (1) to generate prevalence estimates for symptomatic and asymptomatic arrhythmia in the general population and (2) to find risk factors for these arrhythmias from behavioural, general medical and genetic areas.

Methods

A cross-sectional health survey was conducted in North-East Germany 1997-2001 [7]. Seven thousand and eight men andwomen (20-79yrs) were randomly selected from population registries, stratified by gender and 5-year age strata. 6267 subjects could be contacted, 4310 subjects (2193 women) took part. The first follow-up (SHIP-1) started in October 2002. Major parts of the SHIP baseline examination (SHIP-0) are repeated in order to measure the progression of examination parameters. The focus of SHIP is broad and includes cardiovascular, cerebrovascular and thyroid diseases, dental and craniomandibular function and lifestyle related diseases. Various measures of cardiac endpoints are included, methods include 12-lead ECG, echocardiography, treadmill stress testing, and measurements of endothelial dysfunction.

In addition to the SHIP-1 core examination, subjects are invited to participate in associated projects. One of them is the "TeleECG" about which we report here. Participants use the ECG card (Sensor Mobile 100, Telemedizinische Systeme (TMS), Chemnitz) for 4 weeks and record two ECG sequences daily. In addition, subjects are also informed to record an ECG after or during symptoms, which might occur. The card can save three ECGs, 30sec each. ECGs are then sent via telephone to TMS and from there, PDF-files of the ECGs are sent to our study-center via e-mail. An automated routine writes data about incoming ECGs into a MS-Access data base. PDF files are then copied to a file server, where physicians can access them. A MS-Access front end allows physicians to see which ECGs have recently been delivered and await reading. All data management tasks and data analyses are done with The SAS System v8.2 (SAS Institute Inc., Cary, NC, USA). The front end has tools for entering dates and times of issue and return of ECG cards.

Additionally, alexithymic personality traits are assessed with the 20-item Toronto Alexithymia Scale (TAS-20), which is applied as a self-administered questionnaire [8], [9]. The alexithymia construct was developed to describe deficits in emotional processing and awareness. Alexithymia has frequently been related to autonomic dysregulations and increased sympathetic tone and may therefore be related to arrhythmias.

By daily visual inspection of the ECGs through study doctors, arrhythmia categories such as supraventricular extrasystoles, supraventricular tachycardia and ventricular extrasystoles are analysed.

Data safety is provided by the fact, that a single ECG is linkable to a living person only through two link tables: one links the personal information to a six-digit subject number and the other links this subject number to a seven-digit card number. Via card number, date and time of an ECG recording, the ECG can be linked to the subject.

The quality management system includes reader training, certification and calibration, daily reading of recently sent ECGs, automated warning schemes for subjects with a low compliance and those sending the same ECGs twice. Semi annual reports are given to an external data safety and monitoring committee (DSMC).

Results

The project feasibility was tested in a pretest Feb-Apr 2002 together with SHIP-1 core examinations. Of 55 subjects in the core pretest, 48 took part in the TeleECG pretest (87%). Physicians were trained and certified with a subset of 1351 of all pretest ECGs. The main study started on December 16, 2002 after two study physicians were trained and certified. Examiners participated in the certification procedures to assess intra- and inter-reader-variability. A nearly perfect agreement was observed with respect to the quality rating (kappa 0.84-0.94). The intra-reader variability was low with respect to supraventricular (kappa 0.75-0.95) as well as ventricular extrasystoles (kappa 0.86-0.96).

The participation rate was > 60% up to Sept. 30, 2003. 72% of the participants sent at least 80% ECGs for four weeks. Only 11.7% sent less than half of the required number. The total number of recorded and sent ECGs was approximately 25,000 up to September 2004.

Before reading the ECGs, the readers evaluate the ECG quality in three categories: (1) good quality, no artifacts, (2) some artifacts, but readable, (3) complete artefact, not readable. "Good quality" was present in 94.0% of all ECGs.

Only few technical problems occurred: on one occasion the university email server was not working and emails containing the ECG files could not be delivered. TMS could handle this and sent the lost emails again later. On another occasion the TMS email system sent an email twice, resulting in saved attached files with wrong file names, which caused problems with transferring the files to our file server. Another problem that occurred once was, that the university email server virus scan utility would not accept the email.

Discussion

This paper reported on the first inclusion of a TeleECG in a large epidemiological study. The functionality and ergonomics of the TeleECG cards are sufficiently developed and the technical and logistic regime can be used in further studies. Amongst the studies that investigate the prevalence of cardiac arrhythmias, this study is the first to also consider intermittent cardiac arrhythmias. This study will further provide insights into the role of potential cardiac and non-cardiac risk factors. SHIP quality standards which are in line with the recommendations of the German Society of Epidemiology with respect to Good Epidemiological Practice will ensure high accuracy of the expected findings. The SHIP-1 core study is going on until June 2006. With an estimated total number of 3500 participants in SHIP-1, the total number of participants in the TeleECG project could be above 2000, and with a mean number of 50 ECGs per subject, the grand total at the end of the study might be more than 100,000 single ECGs.


Acknowledgements

The research work reported is funded by grants from the German Federal Ministry for Education and Research (BMBF, grants no. 01 ZZ 96030 and 01 ZZ 0103), of the Ministry for Education, Research and Cultural Affairs and the Ministry for Social Affairs of the State of Mecklenburg-West Pomerania as well as the Municipal Hospital of Stralsund GmbH. This project was further supported by BIOTRONIK GmbH (Berlin, Germany)


References

1.
Algra, A., et al., Contribution of the 24 hour electrocardiogram to the prediction of sudden coronary death. Br Heart J, 1993. 70(5): p. 421-7.
2.
Huikuri, H.V., A. Castellanos, and R.J. Myerburg, Sudden death due to cardiac arrhythmias. N Engl J Med, 2001. 345(20): p. 1473-82.
3.
Frolkis, J.P., et al., Frequent ventricular ectopy after exercise as a predictor of death. N Engl J Med, 2003. 348(9): p. 781-90.
4.
Benjamin, E.J., et al., Impact of atrial fibrillation on the risk of death: the Framingham Heart Study. Circulation, 1998. 98(10): p. 946-52.
5.
Raiha, I.J., et al., Predictive value of continuous ambulatory electrocardiographic monitoring in elderly people. Bmj, 1994. 309(6964): p. 1263-7.
6.
Falk, R.H., Atrial fibrillation. N Engl J Med, 2001. 344(14): p. 1067-78.
7.
John, U., et al., Study of Health In Pomerania (SHIP): a health examination survey in an east German region: objectives and design. Soz Praventivmed, 2001. 46(3): p. 186-94.
8.
Parker, J.D., G.J. Taylor, and R.M. Bagby, The 20-Item Toronto Alexithymia Scale. III. Reliability and factorial validity in a community population. J Psychosom Res, 2003. 55(3): p. 269-75.
9.
Taylor, G.J., R.M. Bagby, and J.D. Parker, The 20-Item Toronto Alexithymia Scale. IV. Reliability and factorial validity in different languages and cultures. J Psychosom Res, 2003. 55(3): p. 277-83.