ASPIRIN USE AND LUNG, COLON, AND BREAST-CANCER INCIDENCE IN A PROSPECTIVE-STUDY

A large body of experimental data and several recent epidemiologic stu dies indicate that aspirin use may decrease cancer risk. The experimen tal studies found effects at many anatomic sires, whereas the epidemio logic studies saw the great est effect on mortality from digestive can cers. To provide further human data, we examined the association betwe en aspirin use and cancer risk using data from the National Health and Nutrition Examination Survey I (NHANES I) and the NHANES I Epidemiolo gic Follow-up Studies (NHEFS). Characterization Of aspirin use was bas ed on questions in the baseline interview asking whether subjects used aspirin during;the previous 30 days. Data were available from 12,668 subjects age 25-74, at time of initial examination for NHANES I, who w ere followed for an average of 12.4 years. Among these subjects, 1,257 were diagnosed with cancer more than 2 years after their NHANES I exa mination. Incidence of several cancers was lower among persons who rep orted aspirin use: the incidence rare ratios (and 95% confidence inter vals) for all sites combined were 0.83 (0.74-0.93), lung cancer 0.68 ( 0.49-0.94), breast cancer in women 0.70 (0.50-0.96), and colorectal ca ncer in younger men 0.35 (0.17-0.73). These findings were not readily explained by potentially confounding factors. The data suggest an asso ciation between aspirin consumption and decreased cancer incidence at several cancer sites.