Hypertension – The Silent Killer
What is Hypertension? How do I know if I have it?
Blood pressure is defined as the amount of force or pressure applied to the walls of the arteries with each heartbeat. A blood pressure reading is expressed as a fraction-like measurement with one number on top and another on the bottom. The top (systolic) number represents the amount of pressure exerted on the arteries when your heart contracts. This is when the heart is actively pushing blood out to the rest of the body. The bottom (diastolic) number represents the amount of pressure when your heart rests between beats and is when the heart refills with blood. A normal blood pressure is generally at or below 120/80 mmHg for an adult.
Hypertension is the persistent increase in blood pressure above normal values. A consistent systolic blood pressure between 120 and 139 mmHg with a diastolic value between 80 and 89 mmHg is considered "prehypertensive." Persistent systolic blood pressures of 140 mmHg and above or diastolic pressures of 90 mmHg and above represent hypertension.
Hypertension can be broken down into two stages. Stage 1 is a consistent systolic blood pressure of 140 to 159 mmHg or a diastolic pressure of 90 to 99 mmHg. During this stage, a physician will recommend lifestyle changes such as diet and weight loss and consider adding medication. Stage 2 is a persistent systolic blood pressure of 160 mmHg or higher or a diastolic of 100 mmHg or higher. During this stage, a physician will prescribe blood pressure medication in addition to lifestyle changes. Any blood pressure with a sustained systolic blood pressure of 180 mmHg or higher or a diastolic pressure of 110 mmHg or higher is called a hypertensive crisis and requires emergency medical attention. If left untreated, this can lead to heart failure and stroke.
It is important to note that blood pressure can change periodically based on the demands of the body. For example, it is perfectly normal for it to increase during exercise and times of stress and to decrease when sleeping. In order to diagnose hypertension, a physician may ask you to take your blood pressure at different times of the day over a period of time and record them in a written log. One blood pressure measurement is not adequate for a diagnosis of hypertension.
- Blood Pressure Monitoring at Home - Provides useful information on different blood pressure monitors and how to properly take a blood pressure using a manual or digital cuff.
- High Blood Pressure Fact Sheet - CDC fact sheet on high blood pressure in the U.S., its risk factors, and what the numbers mean.
What Causes Hypertension?
Hypertension is frequently referred to as the “silent killer.” The reason for this reference is because while hypertension can sometimes have subtle symptoms, they are few and may be attributed to other medical conditions. Hypertension over time causes damage to the arteries and places the patient at risk of stroke, heart disease, vascular disease, aneurysm, congestive heart failure, kidney failure, ophthalmic disorders, and other diseases affecting the body.
Primary, or essential, hypertension is high blood pressure that does not have any identifiable cause but is thought to be linked to genetics, obesity, poor diet, and lack of exercise. It can begin at any age and is typically caught during a regular medical check-up. Secondary hypertension is caused by another underlying medical condition such as kidney failure, diabetes, thyroid dysfunction, and more. Treating the underlying condition associated with secondary hypertension can often reduce the risk of serious complications.
Other contributing factors of hypertension are smoking, excessive alcohol consumption, stress, and age.
- Hypertension In Depth - Informational article on hypertension, its causes, symptoms and treatments.
- Causes of Hypertension - NHLBI article on several biological and environmental causes of high blood pressure.
- High Blood Pressure: Why Me? - Harvard Health article on accepting a diagnosis of hypertension.
Complications and Conditions Associated with Hypertension
Hypertension can go undetected for years and as a result complications and conditions can develop after enough damage to the body has occurred. Prolonged hypertension can thicken and harden the arteries causing a condition known as atherosclerosis. This disease process is characterized by plaque buildup along the arterial walls which decreases the flow of blood and oxygen to the heart and body. Because the heart has to work harder to maintain the flow of blood and oxygen, symptoms such as chest pain, shortness of breath, swelling of the extremities and neck, weakness or numbness may occur.
Common complications and conditions associated with this disease process are:
- Heart attack or heart failure
- Peripheral artery disease
- Chronic kidney disease
- Eye damage
- Metabolic syndrome
- Cognitive difficulties
Treatment of Hypertension
Hypertension is associated with an increase in cardiovascular disease. Therefore, it is vital to implement interventions that reduce overall morbidity and mortality. One such intervention is through pharmacological treatment by a physician. There are a number of different medications that a physician can prescribe to control blood pressure. The treatment goal is to keep the blood pressure consistently under 140/90 mmHg if at all possible. The decision of which medication to use will depend on the cause of a person's hypertension and the response to therapy. The following are some of the medications commonly used for treatment.
- Diuretics – Flushes excess sodium from the body to reduce the amount of fluid in the blood.
- Calcium channel blockers – Helps to relax the muscles of the blood vessels by blocking calcium from entering the muscle cells.
- Beta blockers – Reduces the workload of the heart by causing it to beat slower and with less force.
- ACE inhibitors – Prevents the production of Angiotensin II, a hormone responsible for narrowing blood vessels and increasing blood pressure.
- Vasodilators – Works to directly prevent the muscles of the arteries from tightening and narrowing.
- Alpha-beta blockers – Reduces nerve impulses that tighten blood vessels and slows down the heart rate.
- Angiotensin II receptor blockers – Works by blocking the mechanism of action of angiotensin II whereby preventing the constriction of blood vessels.
Additional information on medications prescribed for hypertension:
- High Blood Pressure Treatments and Drugs - Informational article by the Mayo Clinic on hypertension drug treatments, medications and lifestyle changes.
- Commonly Prescribed Blood Pressure Medications - Provides a generic and brand name listing of the most commonly prescribed high blood pressure medications.
- How is High Blood Pressure Treated? - NHLBI article on how hypertension is typically treated, along with classes of medications prescribed and suggested healthy lifestyle changes.
Lifestyle Modifications That Help Control Blood Pressure
In addition to the use of pharmacological treatments, there are other ways to control hypertension. Lifestyle modification through regular physical exercise, maintaining a healthy diet, limiting alcohol intake, quitting smoking, and managing stress are all regularly part of treatment plans developed by physicians to aid in reducing high blood pressure and its long-term effects. The type of treatment plan a person may be prescribed will depend on whether they have primary or secondary hypertension. If a person has primary hypertension, treatment will include lifestyle changes. If a person has secondary hypertension, the physician will work to treat the underlying condition.
Exercise and Hypertension
Regular physical exercise is a key component in the treatment and prevention of high blood pressure as it helps to strengthen the heart which improves its efficiency. A strong and efficient heart pumps blood with less effort thereby decreasing the force on the arteries and lowering blood pressure. Exercise also contributes to an overall healthy lifestyle which is imperative in the control of not only hypertension but also heart disease, diabetes, and obesity.
When introducing a regular fitness routine, it is recommended to start slow. Walking is an excellent way to start exercising. The ultimate goal is to participate in an exercise that raises the heart rate for at least 30 minutes 4-5 days per week. Aerobic exercise has the best impact on blood pressure. Persons with hypertension should avoid exercises that cause sudden and dramatic increases in blood pressure. These would include physical activities like sprinting or heavy weightlifting which puts a large strain on the heart and blood vessels.
If your blood pressure is currently above recommended range ideal for your age, do not start an exercise program without speaking to your physician first.
Additional exercise resources
- Drug-Free Exercise Approach to Controlling Hypertension - Mayo Clinic article on how exercise lowers blood pressure, how much exercise is needed, tips on weight training, and when you need your doctor's okay.
- Exercising Your Way to Lower Blood Pressure - ACSM brochure on exercising to lower blood pressure. Includes blood pressure facts, treatment choices, and ways to improve your health.
Can I Exercise Too Much?
Your body will let you know how much it can handle. It is completely normal for you to breathe harder and sweat. Stop exercising immediately if you experience shortness of breath, lightheadedness, dizziness, weakness, or chest pain. If symptoms do not subside or occur again, notify your physician or seek emergency treatment.
The DASH diet
Diet is a major factor in controlling blood pressure. Healthy eating can reduce the risk of developing hypertension and lower it for those who already have this condition. A dietary plan called the DASH diet is often recommended by physicians. DASH stands for “Dietary Approaches to Stop Hypertension.” This diet employs a handful of approaches that most people have likely already heard before as it is also used in line with recommendations for the prevention of diabetes, stroke, heart disease, and osteoporosis. Its approaches include;
- Limiting sodium and sugar intake
- Eating more fruits and vegetables
- Cutting back or eliminating foods high in cholesterol, saturated fat, or trans fats
- Eating more whole-grain foods
- Consuming low-fat dairy foods
- Reducing red meat intake and increasing intake of fish, poultry, and legumes
In addition to losing weight and guarding against obesity, limiting salt intake is imperative for those who have hypertension or are at risk. Water follows sodium, so with a diet high in salt, the body will retain water which will, in turn, increase blood pressure. A person with hypertension should refrain from adding table salt to their diet.
Here are additional resources to assist in understanding the DASH diet and dietary options for those with hypertension.
According to the CDC, roughly 75 million adults in the U.S. have hypertension. This number equates to 1 in every 3 adults, and only half of these actually have their condition under control. Hypertension also contributed to more than 1,100 deaths per day in 2014. Because hypertension typically has no obvious symptoms, regular yearly screening by a licensed physician will assist in improving these statistics. While there is no cure for this condition, maintaining a healthy lifestyle and following treatment plans set forth by your doctor will go a long way towards living a long a healthy life.