Effect of smoking on sudden and premature death.

BACKGROUND

Smoking has been related to coronary heart disease, and, in men, to sudden death. The results of a case-control study designed to assess the relationship between smoking and all causes of sudden and premature death are reported.

METHODS

A questionnaire on the previous history and causes of death of all people buried in the Municipal Cemetery of Valencia (1986-1987) was administered to the relatives of the deceased. Among 4718 deaths, 284 victims of sudden death were identified, and 495 people who had not died suddenly were randomly sampled as controls.

RESULTS

The proportion of smokers among the women studied was extremely low in contrast to 58.9% of men in the sudden death study group and 59.2% of men in the non-sudden death study group who smoked. Smokers died on average 10 years younger than non-smokers in the sudden-death group (63.3 +/- 12.3 and 73.3 +/- 11.0 years respectively; P < 0.001), and 8 years earlier in the non-sudden death group (68.5 +/- 13.3 and 76.8 +/- 13.2 years, respectively; P < 0.001). A logistic regression model showed that smokers had an adjusted relative risk of 0.81 for sudden death compared with non-smokers (95% confidence interval [CI]: 0.45-1.46). Smokers 65 years of age or under had a 2.7 times greater risk (95% CI: 1.49-5.04) of premature death than non-smokers. Similar results were found in patients from the coronary- and cardiac-death subgroups.

CONCLUSIONS

Smoking is an independent risk factor for premature death but not for sudden death.