A history of hypertension and its treatment
Hypertension, also known as raised blood pressure, was first detected by the Chinese around 2600BC. They measured the quality of the pulse and referred to hypertension as a ‘’hard pulse’. The treatment for a ‘hard pulse’ was bloodletting or the application of leeches.
It was only in 1896 that the first wrap-around rubber cuff was invented to measure blood pressure. In the early part of the 20th century, doctors were still unable to treat blood pressure effectively and were not even sure that it should be lowered, despite descriptions of hypertension as a disease in the 19th Century.
The first effective treatment for hypertension became available in the late 1950s when doctors finally started to realise the importance of controlling blood pressure in their patients.
Hypertension today
Today hypertension is an extremely common disorder, especially in older age groups. It is so common that people sometimes forget that it can have fatal outcomes if not treated properly. Results of untreated blood pressure are damage to the eyes, heart, kidneys and brain.
Hypertension generally has no symptoms, so the only way to know that you have it is to get your blood pressure checked. Some people may experience dizziness, headaches, blurred vision or shortness of breath combined with raised blood pressure though.
Measuring blood pressure
Blood pressure measures how strongly the blood pushes against the artery walls. It is measured in mmHg (millimeters of Mercury (Hg), a unit of pressure measurement) and is recorded as two readings, namely Systolic (when your heart contracts to push the blood out) and Diastolic (when the heart rests). A person is diagnosed with hypertension when the pressure of blood in the arteries remains consistently elevated, i.e. above 140/90mmHg (See table 1 for stages of elevated blood pressure). When blood pressure is elevated, the heart has to work harder to get blood around the body.
The risk of cardiovascular disease
Statistical analysis shows that every increase in blood pressure of 20/10, from a starting point of 115/75, doubles the risk of a cardiovascular event, such as a heart attack. Factors that can elevate blood pressure are caffeine, smoking and strenuous exercise.
In 90% - 95% of hypertensive patients no cause is found for the raised blood pressure. This is called primary hypertension. Secondary hypertension occurs where there is an underlying medical condition, such as kidney disease or endocrine problems, which can result in raised blood pressure.
There are also four different types of raised blood pressure, namely:
1) Most commonly raised systolic and diastolic blood pressure
2) Isolated raised systolic blood pressure, 2 to 4 times increased risk of an enlarged heart, heart attack or stroke.
3) ‘White coat' raised blood pressure - not always harmless
The term white coat hypertension is used when someone has high blood pressure readings (i.e. readings that are consistently 140/90mmHg or above) only when in a medical setting. Blood pressure readings may be normal when taken at home. It can be difficult to establish whether the blood pressure is actually high or just white coat hypertension.
4) Borderline raised blood pressure - blood pressure not persistently raised.
People at risk of raised blood pressure
There is no specific cause of high blood pressure, but the following factors increase your risk of getting hypertension:
- Obesity – your risk is 5 to 6 times greater than for individuals of normal weight
- Having a relative with high blood pressure – this accounts for 30% of hypertensive cases
- Being of African descent
- Excessive salt intake (greater than 5.8 grams daily)
- Lack of sufficient fruit and vegetables in your diet
- Lack of exercise
- Drinking a lot of coffee (or other caffeine-based drinks)
- Drinking a lot of alcohol
- Being older than 65 years of age
Treatment
The goal of treating high blood pressure is, generally, to bring blood pressure below 140/85mmHg, but this depends on whether there are other associated medical conditions such as chronic renal disease or major risk factors like diabetes, in which case the blood pressure needs to be brought down further.
There are several different classes of drugs to treat hypertension and each class has many different medications that can be used. Doctors may also suggest lifestyle changes such as diet and exercise.
Blood pressure needs to be controlled to prevent complications such as kidney damage resulting in renal failure, strokes or heart attacks.
Complications of raised blood pressure
Excessive pressure on the vessel walls can damage those vessels, as well as other body organs. The longer blood pressure is left uncontrolled and the higher blood pressure is, the more damage results, such as:
- Heart attacks and strokes
- Heart failure
- Aneurysms (dilation of the vessels with eventual rupture)
- Weakening and narrowing of kidney vessels eventually resulting in kidney failure
- Eye problems, perhaps even leading to blindness
- Memory problems
Insurance Underwriting considerations
When underwriting an applicant with high blood pressure for a long-term insurance policy, the underwriter needs a blood pressure reading, which may result in a loading or a deferral of cover while the condition is being treated.
The underwriter takes into account other major risk factors that the client may possess for a cardiovascular event (heart attack, stroke) such as:
- Smoking
- Raised cholesterol or triglycerides
- Family history of early-onset cardiovascular disease for men < 55 years and women < 65 years
- Waist circumference for men > 102cm and for women > 88cm
- Age of men > 55 years and of women > 65 years.
Underwriters may also call for further tests on these applicants, to ascertain if the hypertension has already caused damage to blood vessels. Tests may include a stress ECG, a urine test to check for protein in the urine and a blood test.
When making a decision on the case, the underwriters will also take into account any associated medical conditions, such as:
- Vessel disease of the heart (coronary artery disease)
- Heart failure
- Chronic kidney disease
- Strokes or TIAs (Transient Ischemic Attacks)
- Peripherial arterial disease
- Eye problems
At claims stage
Some South African insurance companies will pay for malignant hypertension on a critical illness benefit. Malignant hypertension is very high blood pressure which can come on quickly. The blood pressure is so high that if left untreated it causes damage to the organs such as heart, eye and brain.
Most companies will regard a raised blood pressure which was not disclosed at underwriting stage as significant, especially if the client is claiming for a cardiovascular event. This may result in the client payment being declined.
It is very important for underwriters to receive all information relating to the applicant's health on the application form, to avoid disappointments at claim stage, especially for hypertension.
Table 1
This chart from the NHLB summarizes the different blood pressure categories: |
|||
Category |
Systolic in mmHg |
Diastolic in mmHg |
|
(top number) |
(bottom number) |
||
Normal |
Less than 120 |
and |
Less than 80 |
Pre hypertension |
120 to 139 |
or |
80 to 89 |
Stage 1 HBP |
140 to 159 |
or |
90 to 99 |
Stage 2 HBP |
160 or higher |
or |
100 or higher |
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