Coronary Heart Disease among Female Smokers

To the Editor: Although age and consumption intervals overlap, the relative risks of coronary death among smokers and nonsmokers reported by Willett et al. (Nov. 19 issue)¹ in a study of 119,404 female nurses (ages 30 to 55), with a six-year follow-up that began in 1976, are clearly higher than those among the women followed for six years in the even larger 25-state study² that began in 1959. For example, Willett et al. report that among women smoking more than 25 cigarettes a day, the relative risk is 5.4, whereas the earlier data indicate that the relative risk among women.