Family history and the risk of sudden cardiac death as a manifestation of an acute coronary event.
BACKGROUND
Observational studies have suggested that a parental history of sudden death increases one's risk of dying suddenly. This study tested the hypothesis that a family history of sudden cardiac death (SCD) is a risk factor for SCD caused by an acute coronary event.


RESULTS
A retrospective case-control study included (1) consecutive victims of SCD (n=138) whose deaths were verified to be due to an acute coronary event without a history of prior myocardial infarction at medicolegal autopsy, (2) consecutive patients surviving an acute myocardial infarction (AMI; n=254), and (3) healthy control subjects (n=470). Family history of AMI and SCD among the first-degree relatives was ascertained in each study group. The incidence of SCD in the 1223 first-degree relatives of SCD victims was higher (5.2%) than that in the 2326 relatives of AMI survivors (3.3%; odds ration [OR] 1.6, 95% confidence interval [CI] 1.2 to 2.2, P<0.01) or the 3748 relatives of controls (OR 2.2; 95% CI 1.6 to 3.0, P<0.001). The history of SCD in 2 or more first-degree relatives was also higher (10.9%) among SCD victims than among AMI survivors (3.5%; OR 3.3, 95% CI 1.4 to 7.8, P<0.01) or controls (1.1%; OR 11.3, 95% CI 4.0 to 31.8, P<0.001). The family history of AMI did not differ between the SCD and AMI groups. Male gender and current smoking were the only coronary risk factors that were more prevalent among SCD victims than among AMI survivors (P<0.001 for both).


CONCLUSIONS
Subjects with a family history of SCD have an increased risk of dying suddenly during an acute coronary event.
Kaikkonen
Kari S
KS
Department of Internal Medicine, University of Oulu, PO Box 5000 (Kajaanintie 50), 90014 Oulu, Finland.
Kortelainen
Marja-Leena
ML
Linna
Eeva
E
Huikuri
Heikki V
HV
D000368:Aged; D016022:Case-Control Studies; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000209:etiology*; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects; D017741:Survivors