Open Heart 1: doi:10.1136/openhrt-2014-000150
  • Arrhythmias and sudden death

Sudden Unexpected Death in North Carolina (SUDDEN): methodology review and screening results

  1. 1Divisions of Cardiology and Cardiac Electrophysiology, Department of Medicine, UNC Heart and Vascular, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
  2. 2Department of Emergency Medical Services, Wake County, Raleigh, North Carolina, USA
  3. 3UNC Department of Emergency Medicine, UNC-CH, Chapel Hill, North Carolina, USA
  1. Correspondence to Dr Eugene H Chung; ehchung{at}


Objectives This paper describes the methodology for a prospective, community-based study of sudden unexpected death in Wake County, North Carolina.

Methods From 1 March to 29 June 2013, data of presumed cardiac arrest cases were captured from Wake County Emergency Medical Services. Participants were screened into the presumed sudden unexpected death group based on specific and sequential screening criteria, and medical and public records were collected for each participant in this group. A committee of independent cardiologists reviewed all data to determine final inclusion/exclusion of each participant into registry.

Results We received 398 presumed cardiac arrest referrals. Of these, 105 participants, age 18–65 years old, were identified as presumed sudden unexpected deaths. The primary reason for exclusion was survival to hospital (38%). Ninety-five per cent of participants in the presumed sudden unexpected death group experienced an unwitnessed death. Hypertension was present in almost 50%, while dyslipidaemia and diabetes mellitus were present in almost 25% of the same group. In addition, the presumed sudden unexpected death group includes 67.6% males (95% CI 58 to 76) whereas the control group only included 58.9% (95% CI 46 to 55) males.

Conclusions Participant identification and data collection processes identify presumed sudden unexpected death cases and secure medical and public data for screening and final adjudication. The study infrastructure developed in Wake County will allow its expansion to other counties in North Carolina. Preliminary data indicate the study presently focuses on a population demographically representative of North Carolina.

  • Received May 23, 2014.
  • Revision received July 31, 2014.
  • Accepted August 4, 2014.
  • Published 27 August 2014

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

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