Cardiovascular Disease Health Article

Stroke

Stroke, or a cerebrovascular accident (CVA), occurs when the brain does not receive sufficient oxygen-rich blood through blood vessels or when a blood vessel bursts. A stroke may result from blockage of the blood vessels due to a blood clot (ischemic) or from ruptures of the blood vessels (hemorrhagic bursts). Uncontrolled hypertension is a major risk factor for strokes.

Preventing CVD

The symptoms of CVD develop over many years and often do not manifest themselves until old age. Autopsies of young servicemen indicate significant accumulation of plaque and hardening of the arteries (atherosclerosis). Thus, primary prevention for CVD must begin in early childhood. Preventing premature CVD (before age 60) is crucial. Heart attacks between the ages of forty and sixty are primarily due to lifestyle factors.

Smoking, high blood cholesterol, high blood pressure, and lack of physical activity are the most serious risk factors for CVD and heart attack. Controlling one of these risk factors can help control others. For example, regular exercise can help control cholesterol, blood pressure, weight, and stress levels. Smoking is the most preventable risk factor. Smokers have twice the risk for heart attack that nonsmokers have. Tobacco use alters the blood chemistry and increases blood clotting. Nearly one-fifth of all deaths are due to tobacco use, and a smoker lives an average of seven to eight fewer years than a nonsmoker.

The worldwide increase in obesity and type 2 diabetes (in both children and adults) point to a high-fat, high-calorie diet and a sedentary lifestyle. Poverty increases the risk for poor dietary habits and poor access to healthful foods. Many of the world's urban poor have more access to highly processed foods, convenience foods, and fast foods than to fresh fruits and vegetables. But even in the most wealthy and technologically advanced countries, the affluent are choosing to eat more fast foods and processed foods that are high in fat, cholesterol, and sodium. For optimal health, health professionals recommend:

• Maintaining a healthy weight, with a body mass index (BMI) of 18.5–24.9.
• Limiting dietary fat to 30 percent or less of total calories—10 percent saturated fat, 10 percent polyunsaturated fat, and 10 percent monounsaturated fats. Consumers should be aware that ounce for ounce, all sources of fat have approximately the same amounts of calories.
• Limiting saturated fats to 10 percent of calories. Saturated fats come primarily from animal sources (e.g., high-fat dairy and meats), but also are found in coconut and palm oil.
• Limiting polyunsaturated fats to 10 percent of calories. Polyunsaturated fats come primarily from vegetable oils (e.g., corn oil, safflower oil).
• Limiting monounsaturated fats to 10 percent of calories. Monounsaturated fats may have a protective role in heart disease. Excellent sources of monounsaturated fats include olive oils, nuts, avocado, and canola oil.
• Increasing intake of omega-3 fatty acids. Two to four grams daily of omega-3 fatty acids may lower risk for CVD by reducing blood clotting, making platelets less sticky, and lowering triglycerides. Patients should inform their physician if they are using omega-3 supplements, since they may increase the risk of bleeding. Excellent sources of
• omega-3 include fatty fish (such as salmon and sardines), fish oils, and flax seed.
• Limiting sodium intake to 2,400 milligrams per day.
• Increasing potassium intake to at least 3,500 milligrams per day.
• Eating at least five servings a day of fruits and vegetables.
• Eating a plant-based diet consisting primarily of whole grains, fruits, and vegetables is also recommended.
• Eating at least 25 grams of fiber daily.
• Eating 25 grams of soy protein daily.

In addition to diet modification, research is increasingly focused on the role of physical activity in preventing CVD. People who are not physically active have twice the risk of heart disease as those who are active. More than half of U.S. adults do not achieve recommended levels of physical activity. Studies indicate a correlation between the amount of television viewing, playing videos, and other sedentary activities and increased rates of childhood obesity. In general, the more sedentary the activities, the more high-fat and sugary foods are consumed. At least thirty minutes of moderate physical activity, five times a week, is recommended. Moderate physical activity slows down the narrowing of the blood vessels, due to contraction of the smooth muscles in the vessel walls. It also increases coronary blood flow, strengthens the heart muscles, and reduces stress.

Worldwide, HTN is linked to about 50 percent of CVDs and approximately 75 million "lost healthy life years" each year. Thus, controlling HTN may greatly reduce the risk of disability and death from CVD. Secondary prevention involves treating the signs and symptoms of CVD. These strategies include management of hypertension, cholesterol, and other blood lipids. Dietary and lifestyle modification are tried first. However, medication may also be prescribed, depending on other clinical factors. Compliance with a medication regimen is extremely important, as is the monitoring of blood pressure and blood lipids. Recommended total serum cholesterol should not exceed 200 milligrams per deciliter (mg/dl); low-density lipoproteins (LDLs or "bad cholesterol") should not exceed 100 mg/dl, and high-density lipoproteins (HDLs or "good cholesterol") should not be lower than 40 mg/dl.