Abstract 14513: A Bayesian Analysis of Circadian Variation in Sudden Death in Wake County, North Carolina

Introduction: Sudden death is often attributed to coronary artery disease. Demonstrating that sudden death exhibits a different circadian profile than coronary artery disease would support the emerging concept that sudden death is a syndrome, with multiple etiologies.

Hypothesis: Sudden death will demonstrate a circadian peak with deaths more frequent in the morning hours.

Methods: The study analyzed 399 sudden death victims aged 18-64 attended by Wake County Emergency Medical Services (EMS) from 2013 to 2015. Time of death was determined using EMS records and medical examiner reports. When time of death could not be reliably determined for a victim, the victim was removed from the study. Only 169 deaths (42.3%) where time of death was reliably known to within one hour were included in the final analysis. Bayesian hierarchical modeling identified the location and/or absence of peak times for sudden death victims overall and subgroups with heart failure (19), coronary artery disease (40), hypertension (89), and respiratory disorders (48).

Results: Time of death for all-cause sudden death victims spanned from 6:30 AM to noon, with no evidence of a specific, circadian peak. However, sudden death victims with underlying chronic heart failure displayed a strong circadian peak around 7:00 AM, while respiratory disorder cases showed a limited peak in the mid to late morning. Victims with coronary artery disease and hypertension exhibited no peak (Figure 1).

Conclusions: Sudden death victims lack a distinct overall pattern for time of death. However, individuals with underlying heart failure and possibly respiratory diseases demonstrate a circadian pattern. These findings support the notion that sudden death has multiple causes beyond coronary artery disease. Future preventive interventions should consider the diverse etiologies of sudden death.