Alcohol and sudden cardiac death

OBJECTIVE: To assess the relation between alcohol intake and sudden cardiac death--ie, death within one hour of the onset of symptoms. DESIGN: Prospective study of a cohort of men followed up for eight years. SETTING: General practices in 24 towns in England, Wales, and Scotland. SUBJECTS: 7735 men aged 40-59 at screening who were selected at random from one general practice in each of 24 towns. MAIN OUTCOME MEASURE: All deaths from ischaemic heart disease with particular reference to those that were sudden (death within one hour of the onset of symptoms). RESULTS: During the follow up period of eight years there were 217 deaths from ischaemic heart disease of which 117 (54%) were classified as sudden. Although heavy drinkers (more than six drinks daily) did not show a high incidence rate of fatal heart attack, they showed the highest incidence rate of sudden cardiac death. This was seen in both manual and non-manual workers and was most clearly seen in older (50-59) men. Death from ischaemic heart disease was more likely to be sudden in heavy drinkers than in other drinking groups; this phenomenon was seen irrespective of the presence or degree of pre-existing ischaemic heart disease. The positive association between heavy drinking and the incidence of sudden death was most apparent in men without pre-existing ischaemic heart disease, with heavy drinkers showing an increase of > 60% compared with occasional or light drinkers. After adjustment for age, social class, and smoking, heavy drinkers free of pre-existing ischaemic heart disease had a marginally significantly higher incidence rates of sudden death than other drinkers combined (relative risk 2.00, 95% confidence interval 0.98 to 4.8). Additional adjustment for systolic blood pressure reduced the risk to 1.7. CONCLUSIONS: This study suggests that heavy drinking is associated with an increased risk of sudden death. Studies that do not take pre-existing ischaemic heart disease into account are likely to underestimate the adverse effects of heavy drinking on the incidence of sudden death because the effects are not as evident in men with pre-existing ischaemic heart disease.