14 - Blood Pressure and the Benefits of Treatment

Summary

Of all the measurable functions of the body no other has caused greater controversy in the past than that of blood pressure, leading often to violent disagreement between the pure clinician and the life [insurance] underwriter, and even between clinicians themselves. The source of the trouble is that the correlation between blood pressure and mortality is statistical rather than individual.

The one glaring difference [among national and international guidelines for treating hypertension] is their stance on the management of uncomplicated mild hypertension. This may seem a minor matter considering the numerous points of agreement, but of course subjects with mild hypertension far outnumber all other hypertensive patients because of the distribution of blood pressure in the population.

High blood pressure rose to prominence as a health concern with the development of effective antihypertensive drugs. One issue for public health has been methods of preventing hypertension. Another has been the minimum blood pressure level that warrants medical treatment, which affects millions of persons and can have a significant impact on health care costs.

The Statistical Distribution of Blood Pressure Levels

As male coronary heart disease morbidity and mortality rates continued their relentless climb during the 1940s and 1950s, its prevention became the most compelling health problem of the twentieth century. In 1950 about 1.1% of men ages 45–54 and 2.4% of men ages 55–64 died annually. Close to one-third of the deaths in each age group resulted from coronary heart disease compared to 4% from lung cancer and 16% from all cancers combined. Many of the victims were seemingly healthy married men in their forties and fifties. Their deaths left their widows with heavy family and financial obligations, their children without fathers, and their work organizations and communities without their experience and skills. The enormous void created by the loss of so many men at the ages when they made their greatest contributions to society produced a sense of urgency unmatched by any other disease.

At mid-century the most useful predictors of coronary heart disease in healthy individuals were a family history of the disease and blood pressure level.