Hypertension is a disease characterized by an increase in pressure inside the blood vessels (arteries). As a consequence, the blood vessels are progressively damaged, favoring the development of cardiovascular diseases (strokes, myocardial infarction and heart failure), kidney damage and retinal involvement.

It is a very frequent disease, which affects 35% of adults and 68% of those over 65 years of age.

High blood pressure is responsible for a very important part of cardiovascular diseases, which is why it has become a public health problem worldwide.

Causes of Hypertension

The vascular system is a closed-loop in which blood is powered by the heart. In this circuit, arteries carry blood to different organs and tissues, and veins return blood to the heart. When there is an increase in the pressure inside the arterial system, we will speak of high blood pressure. Its causes could be:

Essential or Idiopathic Hypertension (of Unknown Cause). In most cases (9 out of 10 times), high blood pressure is of unknown cause, which is called essential high blood pressure. It is probably due to the combination of a series of genetic (hereditary) factors that predispose to high blood pressure, together with environmental factors that favor its development. These environmental factors include:
- Advanced Age. Aging increases the risk of hypertension. At advanced ages, systolic blood pressure usually rises and diastolic pressure usually remains normal or low.
- Obesity. There is a close relationship between weight and blood pressure, especially if the weight is due to the accumulation of fat in the abdomen. The association of abdominal obesity, hypertension, hyperglycemia, high triglycerides, and low HDL cholesterol is called metabolic syndrome.
- A diet rich in salt and low in calcium and potassium
- Lack of physical activity (sedentary lifestyle).
- Alcohol consumption.
- Stress.
Secondary Hypertension. On all other occasions, hypertension is due to various diseases. These diseases can cause hypertension either because they favor the existence of an exaggerated amount of fluid inside the arteries, or because they favor the contraction of the arteries, thus reducing the capacity of the circuit to contain blood. The diseases that most frequently cause high blood pressure are:
- Kidney diseases. They are the most frequent cause of secondary arterial hypertension. Almost all kidney diseases can raise blood pressure, the most frequent being chronic kidney failure.
- Vascular kidney disease. It refers to the narrowing of the renal arteries as a consequence of arteriosclerosis or other diseases. This causes the kidney to receive less blood and secrete a series of substances that promote contraction of the arteries.
- Coarctation of the aorta. It is a disease present from birth that consists of a narrowing of the thoracic aorta.
- Sleep apnea syndrome.
- Metabolic Diseases:
  - Cushing's disease
  - Hyperaldosteronism
  - Pheochromocytoma
  - Hypercalcemia
  - Hyperthyroidism and hypothyroidism
  - Acromegaly
- Medications: Corticosteroids, high dose estrogens, antidepressants, nasal decongestants, anti-inflammatories, cyclosporine, cocaine, etc.

Know Your Risk

Hypertension generally does not produce any symptoms, which is why it has been called the "silent killer." Usually, when blood pressure is very high, it can lead to a headache. In general, the symptoms of hypertension are derived from the multiple complications that this disease can produce in various organs.

Complications of Hypertension

Cardiac Complications The heart is the organ that is most frequently affected. The heart, having to introduce blood into a system with very high pressure, has to make an extra effort and increases its size, something called ventricular hypertrophy (growth of the cardiac ventricle). This exaggerated and abnormal growth of the ventricle favors the subsequent development of heart failure. Patients with high blood pressure are also at increased risk for coronary heart disease (angina pectoris and myocardial infarction). Heart disease is the leading cause of death in subjects with high blood pressure.

Kidney complications - High blood pressure, together with diabetes, are the leading cause of chronic kidney failure in industrialized countries. In turn, many kidney diseases cause high blood pressure, so it is sometimes not knowing what the first alteration was.
Cerebrovascular complications - Arterial hypertension favors the development of transient ischemic attacks and strokes, but it is also responsible for the progressive brain damage that leads to the onset of vascular dementia. This dementia appears as a consequence of small cerebral infarcts (lacunar infarcts) and lack of irrigation of the cerebral white matter. When blood pressure is very high, a serious complication called hypertensive encephalopathy can occur, consisting of the appearance of headache, nausea, vomiting, decreased consciousness with a tendency to sleep and, sometimes, the appearance of neurological deficits (difficulty speaking or paresis of the extremities). Left untreated, it can lead to coma, epileptic seizures, and death.
Hypertensive retinopathy
Other complications - High blood pressure is also related to the risk of arteriosclerosis in the aorta and peripheral arterial circulation

Hypertension Diagnosis

Each time blood pressure is taken, there are two values, expressed in millimeters of mercury (mmHg), which are usually noted separated by a line (for example 130/80 mmHg):

Systolic Blood Pressure - It indicates the pressure inside the circuit coinciding with the heartbeat. When the heart pumps blood into the arteries the pressure rises.
Diastolic Blood Pressure - It is the pressure of the arterial circuit during diastole, the moment when the heart is relaxed.

There is a third value called pulse pressure and it is the subtraction between systolic and diastolic blood pressure. Elevated pulse pressure has been shown to be highly associated with the risk of cardiovascular complications.

The diagnosis of hypertension requires the measurement of blood pressure in the arm in a sitting position after resting for 10 minutes, and the result must be corroborated on 2 or more occasions separated in time.

Classification of blood pressure according to the American Heart Association (AHA) 2018:

Normal: <120/80 mmhg
High: 120-129 and <80 mmhg
Grade 1 hypertension: 130-139 or 80-89 mmhg
Grade 2 hypertension: ≥140 or ≥90 mmhg
Hypertensive crisis: > 180 and/or > 120 mmhg
Isolated systolic hypertension ≥140 and <90 mmhg

In children and young people, the blood pressure values considered high are different, depending on age, sex, and height.

In some patients, arterial hypertension can also be diagnosed after the placement of a device that automatically measures blood pressure for 24 or 48 hours while patients carry out their normal life (ABPM; Ambulatory Blood Pressure Monitoring). This device makes it possible to relate the tension changes with daily activities and allows to assess the pressure during the day and the pressure at night. There are several studies that have shown that the maintenance of high night blood pressure is data associated with an increased cardiovascular risk.

Other Types of High Blood Pressure

White Coat High Blood Pressure - It is called white coat hypertension when the patient has high blood pressure figures in the doctor's office, but it is normal when taken outside the healthcare environment or when an ABPM is placed.
Patients with white coat high blood pressure will develop true high blood pressure more frequently in the future and have a higher risk of cardiovascular complications than people with normal blood pressure at the doctor's office.
Masked Hypertension - This is the name given when the patient has normal blood pressure values in the doctor's office but presents high blood pressure values when taken outside the healthcare setting or when an ABPM is placed.

Association with Cancer

Elevated blood pressures have been associated with a number of different cancers, with the most consistent and highest link being kidney cancer (as high as 50% increase). Several other cancers, including those of the upper and lower gastrointestinal tract, prostate, breast, pancreas and bladder have been reported, with the risk ranging from 10-40%, however these associations do appear weaker than that of kidney cancer. These associations have been observed with a systolic blood pressure elevation >10 mmHg, while being weaker for the diastolic blood pressure elevation.

Women appear to have a significant increased risk with several cancers, especially with kidney cancer in particular, having a 54% higher risk compared to that of men. A dose-response relationship has also been reported, such that a 5%-7% higher risk for kidney cancer was reported for every 10 mmHg higher systolic and diastolic blood pressure.

Treatment of Hypertension

High blood pressure is a chronic disease that is not cured but can be controlled with various hygienic-dietary measures and medication. However, the disease usually progresses with age, and it is common for new drugs to be added to the treatment over the years. Treatment allows reducing the number of complications in various organs and reduces mortality.

Hygienic-Dietary Measures

They are aimed at reducing blood pressure and reducing the risk of cardiovascular and kidney complications:

Hypertensive patients should follow a diet rich in fruits, vegetables, and legumes, which will provide an adequate supply of calcium, magnesium, and potassium. The diet must have a low content of salt (<6 grams daily). In addition, salty foods such as cheeses, cold meats, preserves, envelope soups, precooked foods, snacks (olives, fried potatoes, nuts, etc.), cod should be avoided. In addition, plant-based dietary recommendations should be followed.
Alcohol consumption should be minimized/eliminated.
In obese or overweight patients, weight reduction should be recommended through a low-calorie diet and increased physical activity. A moderate decrease in weight can be accompanied by significant reductions in blood pressure.
Tobacco use should be stopped.

Pharmacological Measures for Hypertension

There are several groups of drugs that lower blood pressure. Each of these groups presents a series of adverse effects and a series of specific benefits for certain groups of patients. Although it is convenient to individualize the type of medication to be administered, as the disease evolves, it is usually necessary to add new medications for the adequate control of blood pressure. The most widely used pharmacological groups are:

Diuretics - They are medicines that lower blood pressure by reducing the amount of fluid inside the blood circulation by promoting its elimination in the urine: examples of diuretics are hydrochlorothiazide, amiloride, indapamide, furosemide, or torasemide.
Angiotensin-converting enzyme inhibitors - Within this group, it is found in captopril, enalapril, ramipril, etc. They prevent the action of a substance that facilitates the contraction of the arteries. They are one of the most widely used pharmacological groups.
Angiotensin II receptor antagonists (ARA II) - such as losartan, irbesartan, olmesartan, etc. They also prevent contraction of the arteries.
Direct renin inhibitors.
Calcium antagonists - They facilitate the relaxation of the arteries. Among them are nifedipine, amlodipine, verapamil, and diltiazem.
Beta-blockers - In addition to reducing blood pressure, they slow down the heart rate. They are also used in patients with coronary heart disease and heart failure. Among them are propanolol, atenolol, etc.

Figure Out Your Cancer Risk

Sources

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Causes and Symptoms of Hypertension (HTN) in 2021