This is the first post in our high blood pressure information series which we have started for the benefit of all our readers who or whose loved ones are either suffering from hypertension or are in the pre-hypertensive state. According to a recent survey done in the US, nearly 1 in 3 suffer from high blood pressure and more than half don’t have it under control. What it means is that about 75 million American adults (32%) have high blood pressure. If you go through the statistical data worldwide, the number of people with uncontrolled hypertension rose from 600 million in 1980 to nearly 1 billion in 2008 and is rapidly growing post-2008.
We are not mentioning these numbers to intimidate you. We just want you to be careful and manage your hypertension properly if you have already been suffering from it. Having a strong foundation of the basics of high blood pressure and its management options gives you a great edge in the fight against the hypertension monster.
What is Blood Pressure and When Does It Become ‘High Blood Pressure’?
‘Blood pressure’ is the force of blood pushing against the walls of the arteries as the heart pumps blood. It is measured in Millimeters of Mercury. If your blood pressure is around 120/80 mm Hg it is called “Normal blood pressure”.
In this 120 mm Hg is the systolic blood pressure which is the amount of pressure that blood exerts on arteries and vessels while the heart is beating. And 80 mm Hg is the diastolic pressure that is the pressure that is exerted on the walls of the various arteries around the body in between heartbeats when the heart is relaxed.
When the blood pressure starts to move upwards and shows fluctuations consistently it becomes a matter of concern. Blood pressure in the range of 120-139 or 80-89 is called ‘Prehypertension‘. This is just before you develop high blood pressure and can be easily managed by lifestyle changes and exercises.
When the blood pressure rises between 140-159 or 90-99 you have entered the Stage-1 of hypertension. It is the time to take action and make the necessary lifestyle changes. When the normal blood pressure fluctuates beyond 160 or higher(Systolic) and 100 or higher(diastolic) it is called Stage-2 hypertension and it is the time for you to press the ‘panic button’ and take immediate actions to bring the blood pressure to normal.
What Are The Types of High Blood Pressure?
Hypertension can be mainly divided into two types.
Essential hypertension or primary hypertension– that has no known cause. It affects the maximum number of people in the world. If you have higher than normal blood pressure and if it can’t be linked to any disease then you have primary hypertension. It affects 95% of the people.
Secondary hypertension – is one that has a known cause, is often caused by reversible factors. So once the cause is cured blood pressure comes back to normal. This may be caused by kidney disorders, thyroid dysfunction or may be related to other conditions like pregnancy. Approximately 5% of patients with hypertension have specific causes.
There are a number of conditions that can cause secondary hypertension.
Some of the important ones are as follows-
- Renovascular hypertension-Caused by narrowing (stenosis) of one or both arteries leading to the kidneys.
Renovascular hypertension can cause severe hypertension and irreversible kidney damage.
- Sleep apnea- A condition in which a person has brief spells in which he or she stops breathing during sleep.
Most of these patients suffer from hypertension.
- Pregnancy- Pre-eclampsia, and eclampsia are always associated with hypertension.
- Diabetic nephropathy- Damage to the kidneys in severe cases will mostly lead to hypertension.
- Genetic causes- Condition like Glucocorticoid-remediable Aldosteronism is an autosomal dominant disorder which is the cause of early onset hypertension.
- Cushing’s syndrome- The adrenal glands produce too much of the hormone cortisol. This raises blood pressure. This is mainly caused by corticosteroid medications, a pituitary tumor or some other factors.
- Thyroid problems- Both hypo and hyperthyroidism can cause secondary high blood pressure.
- Pheochromocytoma- This is an Adrenal gland tumor which causes an increase in the secretion of epinephrine and norepinephrine hormones which result in an increased blood pressure.
- Polycystic kidney disease- In this case, cysts in the kidneys are the main cause of hypertension.
- Drugs- Some of the drugs like Cyclosporine (Sandimmune), Tacrolimus (Prograf), Celecoxib (Celebrex), Rofecoxib (Vioxx) can raise the blood pressure temporarily.
Hypertension can be again divided into less common types like-
Resistant Hypertension- If blood pressure cannot be reduced to below 140/90 Mm Hg, despite a triple-drug regimen it is called resistant hypertension.
Malignant Hypertension– is severe and progressive. It is not related to any type of malignancies or cancer. It is the most severe form of hypertension. If untreated will rapidly lead to organ damage. The death rate is high in uncontrolled cases. Death will usually occur due to cardiac arrest, kidney failure or hemorrhage. The incidences of malignant hypertension have become rare in today’s world due to the advancements in the field of medicine.
White coat hypertension- also known as anxiety induced hypertension. As the name suggests in these type of patient’s blood pressure is only high when tested by a health professional. Otherwise, they have a normal blood pressure. But regular follow up is required in such patients to ensure that persistent hypertension has not developed.
And confirming the condition outside a clinical setup or by using a monitoring device at least for 24 hours is highly recommended.
Isolated Systolic Hypertension- In this case the systolic blood pressure is consistently above 160 mm Hg, and the diastolic below 90 mm Hg. Occurs mainly in older people because of stiffened arteries due to aging. Treatment options include lifestyle changes and if required added medications. Treatment is a must to minimize the chances of a cardiac failure, hemorrhage or a stroke.
Pulmonary Hypertension- Pulmonary hypertension is a type of high blood pressure that affects the arteries in the lungs and the right side of your heart. Pulmonary hypertension begins when tiny arteries in your lungs, called pulmonary arteries, and capillaries become narrowed, blocked or destroyed. This makes it harder for blood to flow through your lungs and raises the pressure within your lungs’ arteries. As the pressure builds, your heart’s lower right chamber (right ventricle) must work harder to pump blood through your lungs, eventually causing your heart muscle to weaken and eventually fail.
Morning Hypertension-Morning hypertension is a condition characterized by high blood pressure in the morning and controlled levels throughout the day.
Causes Of High Blood Pressure
Causes of high blood pressure mainly can be related to our food choices and our lifestyle. As we know high blood pressure has been mainly divided into two types.
Primary or essential hypertension – Where there is no definite identifiable underlying cause and
Secondary hypertension – Which has an identifiable underlying cause.
Studies have shown that even with the absence of identifiable underlying causes in primary hypertension, many cases show similar lifestyle and food habits in the people affected by hypertension. Based on the studies done on hypertensive patients over many decades, the causes can be listed as follows.
Causes of high blood pressure in primary or essential hypertension
- Obesity or overweight
- Excessive consumption of alcohol
- Lack of physical activity
- Salt-rich diet
- And finally genetics or family history
Almost two-thirds of the people suffering from obesity have hypertension. There are many ways by which, obesity causes an increase in the blood pressure Obesity causes an increase in cardiac output resulting in an increase in the volume of the blood pumped out of the heart and hence will result in an increased arterial resistance. This increased resistance in the blood vessels causes high blood pressure.
Another theory is related to the hormonal changes caused due to an increase in body weight. Obesity induces a high secretion of insulin in trying to decrease the excessive sugar concentration in the blood.
This excessive insulin secreted results in vasoconstriction, excessive water retention and absorption of salts and mineral. An excess amount of salt results in an increased blood pressure. These hormonal changes brought about by obesity also affect the rennin-angiotensin-mechanism in the body which regulates the blood pressure mechanism. A change in this mechanism brings an increase in blood pressure.
Smoking and Alcohol
The nicotine present in tobacco and cigarettes is mainly responsible for hypertension and other health-related issues. Nicotine is a stimulant which acts to increase the heart rate and also constrict the vessels.
- Vasoconstriction or narrowing of the blood vessels- it forces the heart to pump harder to meet the bodily needs which result in hypertension.
- Damages cells that line coronary arteries and other blood vessels
- It is assumed that alcohol also causes vasoconstriction similar to nicotine resulting in increased blood pressure.
Some of the factors that can be linked to aging which cause hypertension are
- Hormonal changes due to aging
- Loss of elasticity in the blood vessels due to aging
- The decrease in the working efficiency of the heart
Salt Rich Diet
- Salt increases blood pressure mainly by excessive water retention.
- It works on the kidneys to make our body hold on to more water. This over retained water puts extra pressure on the kidney and heart causing an increase in the blood pressure.
Causes of High Blood Pressure in Secondary Hypertension
Chronic kidney disease– Kidney diseases like polycystic kidney disease, glomerular disease, and renovascular hypertension are a few of the main causes of secondary hypertension.
Sleep apnea- Sleep apnea is the repeated pausing of breathing while sleeping so that one or more breaths are missed. This results in a disturbed sleep. Studies have shown that blood pressure drops during deep sleep or sleep in a normal person. But in the case of sleep apnea, blood pressure never drops due to lack of sound sleep causing an increase in blood pressure and more loads on the cardiovascular system.
Pregnancy– Scientists do not know the exact cause of hypertension in pregnancy. But they do know that it is one of the prime causes of hypertension. They usually relate it to the hormonal changes happening in the female body during pregnancy. Two of the conditions that are severe and associated with hypertension in the pregnant woman are preeclampsia and eclampsia. Pre-eclampsia and eclampsia are collectively called the Hypertensive disorder of pregnancy and toxemia of pregnancy.
Adrenal gland tumors– Tumors like Aldosteronism and Pheochromocytoma are the most common ones related to hypertension.
Coarctation of the aorta – It is a condition where the Aorta is narrowed. It is the main artery of the human body. This narrowing causes resistance to the blood flow, thereby causing an increase in blood pressure. Coarctation of the aorta is a congenital anomaly (Seen at the time of birth).
We will discuss how to measure blood pressure and other necessary things in the next part of this hypertension awareness series.