Hypertension refers to high blood pressure. It is a condition in which the force of the blood, being pumped by the heart, against the wall of the arteries (blood vessels that carry blood away from the heart) is too high.
It is a significant medical condition that has effects on many organs of the body such as the heart, brain, kidneys, eyes etc. It is usually a disease of adulthood (>30 years), though children are sometimes affected. When children are affected, it is almost always secondary to another disease condition.
Blood pressure measurement – Blood pressure (BP) is measured with sphygmomanometer, which may be manual or electronic. When blood pressure is measured, the result is written as two numbers, one above (numerator) and one below (denominator).
The numerator represents the systolic blood pressure and it measures the force of the blood on the wall of the arteries when the heart contracts while the denominator is the diastolic blood pressure, which measures the pressure in the blood vessels when the heart relaxes. It is measured in millimetres of mercury (mmHg) (example 120/70 mmHg).
The normal blood pressure should be below 140 mmHg for systolic BP and below 90 mmHg for diastolic BP. The measurement is usually taken when the person has relaxed for at least three to five minutes. This is to minimize the effects of environmental factors on the readings obtained.
Risk factors for hypertension – The risk factors for hypertension can be divided into modifiable (those that can be adjusted for) and non-modifiable (those that cannot be adjusted for).
The modifiable ones include unhealthy diets such as excessive salt intake, food with high fat content, deficient in fruits and vegetables; tobacco, alcohol intake, sedentary lifestyle, anxiety and overweight / obesity.
Non-modifiable risk factors include family history of hypertension, age above 65 years and co-existing diseases like kidney disease, adrenal disease, diabetes, etc. It is important to note that obesity, hypertension and diabetes have a common relationship. Where one occurs, the others tend to be found there.
Type of hypertension – Hypertension can be primary or secondary. Primary hypertension, also referred to as essential hypertension, usually comes with old age. This is diagnosed after finding out that the hypertension has no specific cause.
In this case, usually, there may be family history involving first degree or second degree relatives. Other modifiable and non-modifiable risk factors may be present in such patients.
Secondary hypertension occurs due to disease of some organs in the body such as the kidneys and adrenal glands. This is more common in the young population (< 30 years) than older ones.
Diagnosis of hypertension – Hypertension hardly gives any symptoms. In severe cases, however, some patients may present with unrelieved headache, dizziness or fainting. These are non-specific symptoms. Those with secondary hypertension may manifest with the disease of the primary organs responsible.
For example, those with kidney disease may manifest with swollen face and body, reduced urine output, abnormal urine colour (dark coloured urine) etc. Some may have been on treatment for the primary disease before complication of hypertension sets in. As kidney disease may also be a complication of hypertension, it is important to know which of the diseases comes first.
Since hypertension hardly presents with symptoms, most times, the first evidence of hypertension in patients who do not engage in regular check-up is its complications such as stroke, heart failure, kidney failure etc. Generally, hypertension is diagnosed by blood pressure measurement in an otherwise well patient.
It is diagnosed when high blood pressure is recorded on two occasions, at least four hours apart. If after the two measurements, the systolic blood pressure remains ≥140 mmHg and / or the diastolic blood pressure remains ≥ 90 mmHg, hypertension can be diagnosed.
This BP recheck after few hours and a period of rest is necessary to be sure that whatever readings obtained are real and not due to any environmental influence.
There are, however, times when waiting for the second reading may not be necessary, especially when the first reading is very high (for example, systolic BP ≥ 160 mmHg and / or diastolic BP ≥ 110 mmHg) or the person involved has some symptoms that may result in complications soon, such as headache, vomiting, seeing flashes of light etc.
Waiting for some hours for confirmation in such cases may allow time for the complications of the disease to set in. therefore, prompt intervention is needed in this case.
Treatment for hypertension – Hypertension is a treatable disease; and treatment should be sought before complications set in. Since blood pressure hardly presents with symptoms, it is important to visit hospital and have blood pressure checked at regular intervals so that diagnosis can be made as soon as possible.
The drugs used for hypertension are prescribed by doctors after proper evaluation. This treatment is a continuum and should not be discontinued once it is started unless otherwise stated by the doctor.
Regular check-up to evaluate the blood pressure while on treatment is necessary as there may be need to modify the drugs, reduce or increase the doses; or even discontinue one or some of them for a while.
Sometimes, patients discontinue treatment on their own in erroneous belief that the disease is gone since they are not having any symptom. It should be noted that the drugs used for hypertension are not for cure but to keep the disease in check.
Though in certain cases (such as pregnancy-induced hypertension), hypertension may be transient if it is due to the current clinical status of the patient. When the condition resolves (such as after childbirth), hypertension may resolve too. Except in such conditions, treatment for hypertension, once started, does not stop except with doctor’s instruction.
Complications of hypertension – Complications of hypertension include:
Prevention of hypertension – Hypertension may be prevented by modifying the modifiable factors. These include:
