Over the next thirty years, recorded cases of coronary-heart-disease fatalities increased dramatically, but this rise—the alleged epidemic—had little to do with increasing incidence of disease. By the 1950s, premature deaths from infectious diseases and nutritional deficiencies had been all but eliminated in the United States, which left more Americans living long enough to die of chronic diseases—in particular, cancer and heart disease. According to the Bureau of the Census, in 1910, out of every thousand men born in America 250 would die of cardiovascular disease, compared with 110 from degenerative diseases, including diabetes and nephritis; 102 from influenza, pneumonia, and bronchitis; 75 from tuberculosis; and 73 from infections and parasites. Cancer was eighth on the list. By 1950, infectious diseases had been subdued, largely thanks to the discovery of antibiotics: male deaths from pneumonia, influenza, and bronchitis had dropped to 33 per thousand; tuberculosis deaths accounted for only 21; infections and parasites 12. Now cancer was second on the list, accounting for 133 deaths per thousand. Cardiovascular disease accounted for 560 per thousand.
Another factor militating against the reality of an “epidemic” was an increased likelihood that a death would be classified on a death certificate as coronary heart disease. Here the difficulty of correctly diagnosing cause of death is the crucial point. Most of us probably have some atherosclerotic lesions at this moment, although we may never feel symptoms. Confronted with the remains of someone who expired unexpectedly, medical examiners would likely write “(unexplained) sudden death” on the death certificate. Such a death could well have been caused by atherosclerosis, but, as Levy suggested, physicians often go with the prevailing fashions when deciding on their ultimate diagnosis.
The proper identification of cause on death certificates is determined by the International Classification of Diseases, which has gone through numerous revisions since its introduction in 1893. In 1949, the ICD added a new category for arteriosclerotic heart disease.*4 That made a “great difference,” as was pointed out in a 1957 report by the American Heart Association:
The clinical diagnosis of coronary arterial heart disease dates substantially from the first decade of this century. No one questions the remarkable increase in the
In 1965, the ICD added another category for coronary heart disease—ischemic heart disease (IHD). Between 1949 and 1968, the proportion of heart-disease deaths attributed to either of these two new categories rose from 22 percent to 90 percent, while the percentage of deaths attributed to the other types of heart disease dropped from 78 percent to 10 percent. The proportion of deaths classified under all “diseases of the heart” has been steadily dropping since the late 1940s, contrary to the public perception. As a World Health Organization committee said in 2001 about reports of a worldwide “epidemic” of heart disease that followed on the heels of the apparent American epidemic, “much of the apparent increase in [coronary heart disease] mortality may simply be due to improvements in the quality of certification and more accurate diagnosis….”