Abstract P505: Investigating Sudden Death in a Large North Carolina County: Methods and Findings of a Population-Based Registry

Abstract

Introduction: Evidence on drivers of sudden death (SD) is needed to understand its persistently high incidence and inform prevention interventions. SD studies have been hampered by data limitations and restrictive SD criteria. We conducted a population-based study of all-cause, out-of-hospital SD using Emergency Medical Services (EMS) data from Wake County, a large North Carolina county with >1 million residents. Methods: We screened EMS records of out-of-hospital deaths between 2013-2015 among persons aged 18-64 years, collected medical and death records, and adjudicated 399 SD cases according to a standardized protocol. Deaths occurring in hospices or nursing homes were excluded, as were those due to unnatural death or cancer. Deaths were not excluded by time last seen or coronary artery disease (CAD) criteria. Frequency matched living controls were identified from the same county and time. We compiled and summarized findings based on peer-reviewed papers and published abstracts in Table 1. Results: Cardiovascular disease risk factors were common among decedents, including hypertension (60.4%, 244 of 371), though only 14.8% (55 of 371) had documented CAD. SD cases had lower adjusted mean total cholesterol, low-density lipoprotein and high-density lipoprotein levels compared to controls. Furthermore, left ventricular hypertrophy and inflammation suggested nodes on a common causal pathway. Poor health care management was frequent as well as mental health and substance use problems. Environmental factors such as poverty, air pollution and absence of nearby greenways were associated with SD. Conclusions: Conducting a population-based registry of adjudicated SD cases was feasible and provided high quality data for study. Our findings suggest that SD is not only tied to CAD but a syndrome with potentially different environmental and inflammatory etiologies. Future studies should investigate modifiable risk factors for interventions to prevent SD.