Hypertension is one of the most common worldwide diseases afflicting humans and is a major risk factor for stroke, myocardial infarction, vascular disease, and chronic kidney disease. Despite extensive research over the past several decades, the etiology of most cases of adult hypertension is still unknown, and control of blood pressure is suboptimal in the general population. Due to the associated morbidity and mortality and cost to society, preventing and treating hypertension is an important public health challenge.
It is defined as a systolic blood pressure (SBP) of 140 mm Hg or more or a diastolic blood pressure (DBP) of 90 mm Hg or more, taking antihypertensive medication, or having been told by clinicians on at least 2 occasions as having hypertension (AHA)
Based on recommendations of the JNC 7, the classification of BP (expressed in mm Hg) for adults aged 18 years or older is as follows;
- Normal: systolic lower than 120 mm Hg, diastolic lower than 80 mm Hg
- Prehypertension: systolic 120-139 mm Hg, diastolic 80-89 mm Hg
- Stage 1: systolic 140-159 mm Hg, diastolic 90-99 mm Hg
- Stage 2: systolic 160 mm Hg or greater, diastolic 100 mm Hg or greater
The classification above is based on the average of 2 or more readings taken at each of 2 or more visits after initial screening. Normal BP with respect to cardiovascular risk is less than 120/80 mm Hg.
Risk Factors For Developing Hypertension
A number of factors and variables can put you at a greater risk for developing high blood pressure (HBP or hypertension). Understanding these risk factors is essential to prevention of hypertension.
Non modifiable risk factors
Common hereditary and physical risk factors for high blood pressure include:
- Family history – If your parents or other close blood relatives have high blood pressure, there’s an increased chance that you’ll get it too.
- Age – The older you are, the more likely you are to get high blood pressure. As we age, our blood vessels gradually lose some of their elastic quality, which can contribute to increased blood pressure. However, children can also develop high blood pressure.
- Gender – Until age 64, men are more likely to get high blood pressure than women are. At 65 and older, women are more likely to get high blood pressure.
- Certain defects you’re born with (congenital) in blood vessels
- Race – African-Americans tend to develop high blood pressure more often than people of any other racial background in the United States. It also tends to be more severe in African Americans, and some medications are less effective in treating HBP in blacks. Learn more about African-Americans and high blood pressure.
Modifiable risk factors
These are the risk factors you can change to help prevent and manage high blood pressure, including:
- Lack of physical activity – Not getting enough physical activity as part of your lifestyle increases your risk of getting high blood pressure. Physical activity is great for your heart and circulatory system in general, and blood pressure is no exception.
- An unhealthy diet, especially one high in sodium – Good nutrition from a variety of sources is critical for your health. A diet that is too high in salt consumption, as well as calories, saturated and trans fat and sugar, carries an additional risk of high blood pressure. On the other hand, making healthy food choices can actually help lower blood pressure.
- Being overweight or obese – Carrying too much weight puts an extra strain on your heart and circulatory system that can cause serious health problems. It also increases your risk of cardiovascular disease, diabetes and high blood pressure.
- Drinking too much alcohol – Regular, heavy use of alcohol can cause many health problems, including heart failure, stroke and an irregular heartbeat ( arrhythmia). It can cause your blood pressure to increase dramatically and can also increase your risk of cancer, obesity, alcoholism, suicide and accidents.
- Sleep apnea – Obstructive sleep apnea may increase risk of developing high blood pressure and is common in people with resistant hypertension .
- High cholesterol – More than half of people with high blood pressure also have high cholesterol.
- Diabetes – Most people with diabetes also develop high blood pressure.
- Smoking and tobacco use – Using tobacco can cause your blood pressure to temporarily increase and can contribute to damaged arteries. Secondhand smoke, exposure to other people’s smoke, also increases the risk of heart disease for nonsmokers. Learn more about quitting smoking .
- Stress – Stress is not necessarily a bad thing in and of itself. But too much stress may contribute to increased blood pressure. Also, too much stress can encourage behaviors that increase blood pressure, such as poor diet, physical inactivity, and using tobacco or drinking alcohol more than usual. Socioeconomic status and psychosocial stress can affect access to basic living necessities, medication, healthcare providers, and the ability to adopt healthy lifestyle changes.
Causes Of Hypertension (High Blood Pressure – HBP)
There are two types of high blood pressure.
Primary (essential) hypertension
For most adults, there’s no identifiable cause of high blood pressure. This type of high blood pressure, called primary (essential) hypertension, tends to develop gradually over many years.
Some people have high blood pressure caused by an underlying condition. This type of high blood pressure, called secondary hypertension, tends to appear suddenly and cause higher blood pressure than does primary hypertension. Various conditions and medications can lead to secondary hypertension, including:
- Obstructive sleep apnea
- Kidney problems
- Adrenal gland tumors
- Thyroid problems
- Certain defects you’re born with (congenital) in blood vessels
- Certain medications, such as birth control pills, cold remedies, decongestants, over-the-counter pain relievers and some prescription drugs
- Illegal drugs, such as cocaine and amphetamines
Recommendations to lower BP and decrease cardiovascular disease risk include the following, with greater results achieved when 2 or more lifestyle modifications are combined  :
- Weight loss (range of approximate systolic BP reduction [SBP], 5-20 mm Hg per 10 kg)
- Limit alcohol intake to no more than 1 oz (30 mL) of ethanol per day for men or 0.5 oz (15 mL) of ethanol per day for women and people of lighter weight (range of approximate SBP reduction, 2-4 mm Hg)
- Reduce sodium intake to no more than 100 mmol/day (2.4 g sodium or 6 g sodium chloride; range of approximate SBP reduction, 2-8 mm Hg) 
- Maintain adequate intake of dietary potassium (approximately 90 mmol/day)
- Maintain adequate intake of dietary calcium and magnesium for general health
- Stop smoking and reduce intake of dietary saturated fat and cholesterol for overall cardiovascular health
- Engage in aerobic exercise at least 30 minutes daily for most days (range of approximate SBP reduction, 4-9 mm Hg)
The AHA/ASA recommends a diet that is low in sodium, is high in potassium, and promotes the consumption of fruits, vegetables, and low-fat dairy products for reducing BP and lowering the risk of stroke. Other recommendations include increasing physical activity (30 minutes or more of moderate intensity activity on a daily basis) and losing weight (for overweight and obese persons).
The 2018 European Society of Cardiology (ESC) and the European Society of Hypertension (ESH) guidelines recommend a low-sodium diet (limited to 2 g per day) as well as reducing body-mass index (BMI) to 20-25 kg/m 2 and waist circumference (to < 94 cm in men and < 80 cm in women).
If lifestyle modifications are insufficient to achieve control of blood pressure, there are several drug options for treating and managing hypertension. Your physician will know which of the drug to start you on
Complications of hypertension
The excessive pressure on your artery walls caused by high blood pressure can damage your blood vessels, as well as organs in your body. The higher your blood pressure and the longer it goes uncontrolled, the greater the damage.
Uncontrolled high blood pressure can lead to complications including:
- Heart attack or stroke. High blood pressure can cause hardening and thickening of the arteries (atherosclerosis), which can lead to a heart attack, stroke or other complications. A lot of people are coming down with stroke due to uncontrolled high blood pressure and most are consequence of failed adherence and compliance to medication as prescribed by the doctor
- Aneurysm. Increased blood pressure can cause your blood vessels to weaken and bulge, forming an aneurysm. If an aneurysm ruptures, it can be life-threatening.
- Heart failure. To pump blood against the higher pressure in your vessels, the heart has to work harder. This causes the walls of the heart’s pumping chamber to thicken (left ventricular hypertrophy). Eventually, the thickened muscle may have a hard time pumping enough blood to meet your body’s needs, which can lead to heart failure.
- Weakened and narrowed blood vessels in your kidneys. This can prevent these organs from functioning normally.
- Thickened, narrowed or torn blood vessels in the eyes. This can result in vision loss.
- Metabolic syndrome. This syndrome is a cluster of disorders of your body’s metabolism, including increased waist circumference; high triglycerides; low high-density lipoprotein (HDL) cholesterol, the “good” cholesterol; high blood pressure and high insulin levels. These conditions make you more likely to develop diabetes, heart disease and stroke.
- Trouble with memory or understanding. Uncontrolled high blood pressure may also affect your ability to think, remember and learn. Trouble with memory or understanding concepts is more common in people with high blood pressure.
- Dementia. Narrowed or blocked arteries can limit blood flow to the brain, leading to a certain type of dementia (vascular dementia). A stroke that interrupts blood flow to the brain also can cause vascular dementia.