Abstract P113: Underestimation Of Sudden Death Due To Restrictive Sudden Cardiac Death Criteria

Abstract

Background: Efforts to prevent sudden death may be hampered by restrictive case definitions impairing accurate estimates of incidence and risk factors of sudden death. Sudden cardiac death (SCD) definitions include requirements for presence of comorbid coronary artery disease (CAD) and various time criteria since onset of symptoms or when victims were last seen well. We compared prevalence of three SCD definitions within a registry of all-cause natural, sudden deaths. Hypothesis: We assessed the hypothesis that the restrictive criteria of three SCD definitions underestimate sudden death and exclude populations with increased medical comorbidities. Methods: Using a registry of 399 adjudicated sudden death cases among adults aged 18-64 in Wake County, North Carolina in 2013-2015, we included 271 cases after excluding for missing values, chronic kidney disease, or heart failure. Time since last seen alive was classified as less than one hour or 24 hours from scene reports. Presence of CAD and co-morbidities were defined from clinical or autopsy records. Prevalence of SCD using criteria defined by Atherosclerosis Risk in Communities (ARIC), the World Health Organization (WHO), and the Oregon Sudden Unexpected Death (SUD) registry were calculated. Prevalence of SCD risk factors were calculated for the 3 SCD subgroups and compared to the original 271 victims using two-sample t-test and Fisher’s exact test for continuous and categorical variables. Results: Among the 271 cases, criteria were met for the three SCD definitions for n (%): ARIC 28 (10%), WHO 54 (20%), and SUD 90 (33%) (Table 1). ARIC and WHO-defined SCD cases were younger than the original 271 cases. There were no significant differences in sociodemographic and clinical factors by any SCD group compared to the original 271 cases. Conclusion: Restrictive SCD definitions that require the presence of CAD or a specific time frame of identification of death underestimate the incidence of sudden death and hinder effective prevention efforts for sudden death.