Cardiovascular Risk Factors: The Importance of Controlling
Cardiovascular diseases are the major causes of death and morbidity in the United
States, and result in a huge financial burden on the economy. The misery and disability
that can result from cardiovascular disease is even more devastating. I had a patient
in the hospital who was a vigorous business executive until he had a stroke about
five years ago. He cannot speak and is mainly wheelchair bound.
In the past two decades we have come to recognize the risk factors which cause cardiovascular
diseases and, more importantly, we have learned that we can prevent or reduce the
incidence of these diseases.
One of the cardiovascular diseases we have had most success in preventing has been
strokes. The major cause of strokes in the United States and throughout the world
is high blood pressure, or hypertension. About 50 million people in the United States
have high blood pressure and it is the major medical diagnosis that brings the adult
patient to the physician, yet only 25% of patients have their blood pressure controlled.
As you can see, over 50% of the population above 50 years of age has high blood
pressure and, in many, the blood pressure is either caused or worsened by excessive
salt in the diet. Recognition that treatment of high blood pressure could prevent
stroke has resulted in a dramatic decrease in the incidence of stroke. It has been
calculated that a 1 mmHg drop in blood pressure in a population results in about
a 1% decrease in stroke. A significant decrease in blood pressure, such as 5-10
mmHg, can be achieved by decreasing sodium in the diet and by weight reduction.
We also know that sufficient calcium in the diet is necessary to prevent toxemia
The vast majority of patients with high blood pressure have what we call Stage 1,
or mild hypertension. Even though the hypertension is called mild, it does not mean
that it is benign. It still predisposes to strokes, heart attacks, and heart failure.
The first step is treatment by diet.
The second cardiovascular disease I wish to briefly discuss is myocardial infarction
or heart attack, the number one cause of death in the United States. We have known
since World War II that high blood cholesterol plays an important role in causing
heart attacks. For years we were not certain that lowering the cholesterol made
any difference. Now the evidence is quite clear that lowering cholesterol can reduce
heart attacks. In fact, a 1% decrease in cholesterol can lead to a 2% decrease in
the incidence of heart attacks in the population. Therefore, a 10% decrease in cholesterol,
which is readily achievable with diet, could result in a 20% decrease in heart attacks
which would have a major impact on health care costs in this country. There is more
to heart attacks than just total cholesterol. We know there is a good cholesterol
(HDL) as well as a bad cholesterol (LDL), and many other lipid components that may
contribute to the risk of heart attacks, some of which can be altered by diet. Diet
is the first recommended approach to achieve the desired LDL cholesterol level.
Besides cholesterol, there are other factors to control and we continue to learn
new ones. For example, the amino acid, homocystine, is high in some people with
heart attacks, and lowering the level through dietary nutrients can prevent heart
attacks in some people. Also, antioxidants, such as Vitamin E, may prevent heart
A third cardiovascular risk factor is diabetes. The most common form is Type II
or adult-onset diabetes. The classical Type II diabetic is an obese patient, over
40 years of age and often with a family history of diabetes. The diabetic frequently
has hypertension and abnormal lipids as well. Weight reduction by diet can significantly
improve the control of diabetes. Indeed, dietary treatment is the basis of treatment
of Type II diabetes. Proper treatment can prevent the development of diabetes, as
well as many complications, and obesity control significantly affects diabetes.
In summary, lifestyle modifications are recommended for prevention and control of
cardiovascular risk factors.
Everyone has to eat so dietary management is the natural and cheapest way to start.
However, in general, long-term dietary treatment has been too complicated and the
compliance poor. If we could develop diets that are simple to prepare or obtain
and affordable, compliance would improve and we would have made a major step forward
in the prevention of cardiovascular disease.