Hypertension

What is it? High blood pressure in the arteries is a common condition. High is defined as systolic pressure >140 mmHg or diastolic pressure >90 mmHg. Blood pressure depends on the amount of blood supplied to the arteries by the heart and the amount of resistance to blood flow in your arteries. The more blood and the narrower your arteries are, the higher your blood pressure.

Blood pressure is measured with an inflatable cuff around the arm and a gauge. The blood pressure reading is given in millimetres of mercury (mm Hg) and has two values. The first, or high, refers to the pressure in your arteries when your heart beats (systolic pressure). The second, or small, refers to the pressure in your arteries when your heart is resting (diastolic pressure).

Is high or low pressure more important? Both values of blood pressure are important. But after the age of 50, the value of systolic pressure is even more important. Your doctor will probably measure your blood pressure two and three times at two or more separate appointments before making a diagnosis of hypertension. This is because blood pressure changes throughout the day - and sometimes especially during doctor visits, a condition called the white shirt effect. Your doctor may ask you to have your blood pressure recorded at home and at work to provide additional information.

Are there many forms of hypertension? Blood pressure values are divided into four general categories:

• Normal blood pressure. Your blood pressure is normal if it is below 120/80 mm Hg. However, some doctors recommend a target blood pressure below 115/75 mm Hg. When blood pressure rises above 115/75 mm Hg, your risk of cardiovascular disease begins to increase.
• Prehypertension. Prehypertension is systolic pressure ranging from 120 to 139 mm Hg or diastolic pressure from 80 to 89 mm Hg. Prehypertension tends to get worse over time.
• Stage 1 hypertension. In stage 1 systolic pressure ranges from 140 to 159 mm Hg or diastolic pressure ranges from 90 to 99 mm Hg.
• Stage 2 hypertension. In stage 2, systolic pressure is 160 mm Hg or higher and diastolic pressure is 100 mm Hg or higher.

Do you need more tests? If you have any type of hypertension, your doctor may recommend more routine tests, such as a complete urinalysis (urinalysis), blood tests and an electrocardiogram. Your doctor may also recommend additional tests, such as cholesterol or blood glucose, to check for more factors for heart disease.

How and when does it occur? You can have hypertension for years without symptoms. That's why most people with high blood pressure have no signs or symptoms, even when blood pressure readings reach dangerously high levels. Although some people with early-stage hypertension may have dullness, headaches, dizziness or nosebleeds, these signs and symptoms usually don't appear until hypertension reaches a severe - even life-threatening - stage.

When should you see a doctor? Measuring blood pressure is very easy and can be done by anyone, anywhere. If some consecutive pressure readings are above normal limits, then you should consult your doctor. Since the symptoms of hypertension are non-specific, it is advisable to consult your doctor when they occur.

What causes it? There are two types of hypertension.

• Primary or idiopathic hypertension: for most adults, there is no identifiable cause of hypertension. This type of hypertension tends to progress gradually over many years.
• Secondary hypertension: some people have hypertension due to an underlying disease. This type of hypertension tends to occur suddenly and causes higher blood pressure than primary hypertension. Various conditions and medications can lead to secondary hypertension, such as kidney disease, adrenal tumours, birth defects in blood vessels, certain drugs such as birth control pills, cold remedies, decongestants, painkillers and illegal drugs such as cocaine and amphetamines.

Are there factors that increase its occurrence? Hypertension has many risk factors, including:

• Age. The risk of hypertension increases as we age.
• Gender: It is more common in men. Women are more likely to develop hypertension after menopause.
• Race: Hypertension is particularly common among blacks, in whom more complications occur.
• Family history: Hypertension tends to occur in family members.
• Obesity: The more your weight, the more blood you need to supply oxygen and nutrients to your tissues. As the volume of blood circulating through your blood vessels increases, so does the pressure on your artery walls.
• Lack of exercise: People who do not exercise tend to have a higher heart rate. Lack of physical activity also increases the risk of obesity.
• Smoking: Smoking or chewing tobacco can raise your blood pressure immediately and temporarily. Also, the chemicals in tobacco can damage the lining of your artery wall. This can cause narrowing in your arteries and an increase in blood pressure. Secondhand smoke can also increase your blood pressure.
• Too much salt (sodium) in your diet: Too much sodium in your diet can cause fluid retention in your body that increases blood pressure.
• Too little potassium in your diet: Potassium helps balance the amount of sodium in your cells.
• Too little vitamin D in your diet: Vitamin D can interfere with the action of an enzyme produced by your kidneys that affects your blood pressure.
• Alcohol consumption: Over time, drinking too much alcohol can damage your heart. Drinking more than two drinks a day can raise your blood pressure.
• Anxiety and stress: High levels of stress can lead to a temporary, but dramatic, increase in blood pressure.
• The presence of certain chronic conditions including high cholesterol, diabetes, kidney disease and sleep apnea.

Can it cause me problems? High blood pressure usually develops over many years, and affects almost everyone eventually. Excessive pressure on your artery walls caused by high blood pressure can damage your blood vessels as well as your body's organs. The higher your blood pressure, the more damage that can be caused.

Uncontrolled high blood pressure can lead to:

• Heart attack (heart attack) or stroke.
• Aneurysms. Increased blood pressure can weaken your blood vessels forming an aneurysm. Rupture of an aneurysm is a life-threatening condition.
• Heart failure: in order for the heart to move blood through vessels with high pressure, it has to contract more and so it overstretches (gets bigger). Eventually, hypertrophy can lead to heart failure.
• Kidney failure: Narrowing of the blood vessels in your kidneys can cause kidney dysfunction.
• Narrowing or rupture of the blood vessels in the eyes that can lead to loss of vision.
• The metabolic syndrome. This syndrome consists of an accumulation of your body's metabolic disorders - increased waist circumference, high triglycerides, low levels of high-density lipoprotein (HDL), or "good" cholesterol, high blood pressure and high insulin levels.

What can you do before your doctor's appointment? There is no preparation you can do before your blood pressure check. You can if you want wear a short-sleeved shirt to your appointment so that the cuff fits around your arm properly. You can avoid caffeinated foods and drinks before your blood pressure measurement. You should also use the toilet before the measurement.

Because some medications - such as colds, painkillers, antidepressants, birth control pills and others - can raise your blood pressure, it's a good idea to bring a list of the medications and supplements you take to your doctor's appointment. Don't stop taking any medication that you think may affect your blood pressure without your doctor's advice.

Write down any symptoms you are experiencing. Hypertension rarely has symptoms, but it is a risk factor for heart disease. If you report symptoms such as chest pains or shortness of breath it may help your doctor decide how aggressively hypertension should be treated.

• Note basic personal information, including family history of hypertension, high cholesterol, heart disease, stroke or diabetes, and highlight any recent changes in your life.
• Make a list of all the vitamin medicines or supplements you take.
• Take a family member or friend along if possible.
• Be prepared to discuss your diet and exercise habits.
• Write down the questions you have for your doctor.

What to expect from your doctor? Your doctor is likely to ask you a number of questions such as:

• Do you have a family history of high cholesterol, hypertension or heart disease?
• What your diet includes and if you exercise.
• Do you drink alcohol? How many drinks are consumed in a week?
• Do you smoke?
• When was the last time you checked the pressure and what was the measurement then?