High blood pressure is also medically called hypertension. Blood pressure is the pressure that blood applies on the inner walls of the arteries (blood vessels that carry blood from the heart to the rest of the body).

Blood pressure can be measured at an outpatient desk by a clinician, and the figure obtained analysed as normal, tending to high blood pressure (pre-hypertension) or already high blood pressure (hypertension).

According to World Health Organisation (WHO), raised blood pressure is estimated to cause 7.5 million deaths, about 12.8% of the total of all deaths worldwide and is one of the commonest causes of premature deaths world over . The global prevalence of high blood pressure in adults aged 25 years and above is around 40%. Africa has the highest prevalence at 46% for both sexes combined.

The exact cause of hypertension is not known in up to 90% of the patients, but it can be linked to known risk factors such as obesity, sedentary life style, high salt diet intake, excessive consumption of alcohol, tobacco use, diabetes, aging, family history of hypertension, and generally blacks are at a higher risk of suffering from hypertension. Although certain risk factors such as family history of high blood pressure, age and race can’t be modified, most of the other risk factors can be controlled to reduce one’s risk of suffering from hypertension.

In the remaining 10 per cent of the patients with hypertension, the commonest causes are renal diseases such as chronic kidney disease. Other causes may include; adrenal gland tumors, thyroid gland disease, blood vessel disorders, and some drugs such as birth control pills, cocaine, steroids. High blood pressure as a result of these factors normalizes when the underlying cause(s) is medically corrected.

There are no specific symptoms of high blood pressure; hence despite having life threatening blood pressure levels, most people do not have any signs or symptoms and high blood pressure is detected coincidentally during routine medical checkups. Rarely, one may experience symptoms such as dull headaches, vomiting, dizziness, and more frequent nosebleeds and these symptoms usually do not occur until blood pressure levels have reached a severe or life-threatening stage.

Why high blood pressure should be well controlled

Persistent high blood pressure on the artery walls caused by uncontrolled or poorly controlled high blood pressure can damage blood vessels and body organs. This increases the risk for developing several dangerous health conditions including heart attack, stroke, chronic heart failure, and kidney disease. Approximately 70 per cent of people who have their first heart attack already have hypertension and about 80 per cent of people who have their first stroke have high blood pressure.

Diagnosis of high blood pressure

High blood pressure is diagnosed by measuring one’s blood pressure using a blood pressure machine. This is usually done as part of routine physical examination in a hospital.

It is common and normal for one to have a slightly raised blood pressure level due to anxiety of being examined by a doctor or nurse, and hence the diagnosis of high blood pressure is made when ones blood pressure is persistently raised in at least two or more clinical visits unless the blood pressure is dangerously elevated or there are signs of long-standing hypertension such as organ damage.

Treatment

Treatment of high blood pressure begins with lifestyle changes, and for the people with blood pressure readings tending to hypertension (pre-hypertension), lifestyle changes reduce the risk of progression to hypertension. These changes include; reducing amount of salt in one’s diet, losing weight if overweight, regular physical exercises (at least 40 minutes of vigorous to moderate physical activity for at least 4 days a week), avoiding too much alcohol consumption (maximum 2 drinks per day for man and 1 drink maximum for woman),and stopping cigarette smoking. Eating diet rich in fruits, vegetables, grains, poultry and fish and limiting sweets, sugar sweetened beverages and red meat reduces chances of hypertension.

Once diagnosed with hypertension, in addition to lifestyle changes, medicines which reduce blood pressure to normal values are prescribed and these should be taken as instructed coupled with regular medical follow up by a doctor.

It is important to understand and accept that except for the type of high blood pressure whose specific cause is known and cured by removing the causative condition (about 10 per cent of cases of hypertension), the other form (about 90 per cent of cases of hypertension) has no cure and can only be managed through the above lifestyle changes and medicines for life to avoid consequences of high blood pressure.

Dr Ian Shyaka is a general practitioner based in Kigali.