Alcohol and coronary heart disease in Puerto Rico.

The relationship of alcohol consumption, measured in 1965-1968 by the 24-hour recall method, to incident coronary heart disease morbidity at eight years and mortality at 12 years of follow-up was investigated in a cohort of 9150 Puerto Rican males 35-79 years of age. After adjustment for age, cigarettes, exercise, urban/rural status, and income, there was clear evidence of a "U-shaped" relationship between alcohol and total mortality, and also the suggestion of a "J-shaped" relationship for angina pectoris, nonfatal myocardial infarction, and nonsudden coronary heart disease death. There was no association of alcohol with sudden cardiac death. The adjusted odds ratio for drinkers versus nondrinkers was 0.6 for angina pectoris (p less than 0.05), 0.7 for nonfatal myocardial infarction (p less than 0.1), and 0.7 for nonsudden coronary heart disease death (p less than 0.05). The inverse association of alcohol consumption to nonsudden coronary heart disease death was found to be dependent on age and income: the adjusted odds ratio for subjects under age 60 (0.4) or over the median income (0.3) strongly favored drinkers, while there was no evidence for a "protective effect" of alcohol consumption in the older and poorer segments of the population. It is concluded that available evidence does not justify the assertion that the inverse association between moderate alcohol intake and coronary heart disease risk is a causal one.