High Blood Pressure (Hypertension)

Blood pressure is measured in millimetres of mercury (mmHg) and recorded as two numbers. A reading is considered high when it consistently reaches 130/80 mmHg or above, according to current medical guidelines.

Hypertension is often called the "silent killer" because it typically produces no obvious symptoms, yet quietly causes damage throughout the body. Regular high blood pressure checks are essential for early detection and timely intervention.

What is High Blood Pressure (Hypertension)?

High blood pressure occurs when the force of blood against the artery walls remains persistently elevated over time. The heart must pump harder than normal to circulate blood around the body, placing strain on the cardiovascular system. Left unmanaged, this sustained pressure leads to structural changes in blood vessels and organs, significantly raising the likelihood of life-threatening events such as heart attack and stroke.

Understanding Blood Pressure Readings: Systolic vs. Diastolic

A blood pressure reading consists of two values:

• Systolic pressure (the top number): This measures the pressure in your arteries when your heart beats and pumps blood. A normal systolic value is below 120 mmHg.
• Diastolic pressure (the bottom number): This measures the pressure in your arteries when your heart rests between beats. A normal diastolic value is below 80 mmHg.

A reading of 120/80 mmHg is considered normal. A very high blood pressure reading of 180/120 mmHg or above is classified as a hypertensive crisis and requires immediate medical attention.

Risk Factors for High Blood Pressure

Understanding the reasons for high blood pressure is the first step toward prevention. Several factors can increase your risk of developing hypertension:

• Age: Blood pressure tends to rise with age. Men are at greater risk before age 64, while women are more susceptible after 65.
• Family history and genetics: Hypertension often runs in families, suggesting a strong hereditary component.
• Obesity or being overweight: Excess body weight increases demand on the heart and raises blood pressure.
• Physical inactivity: A sedentary lifestyle is closely linked to elevated blood pressure and cardiovascular disease.
• Unhealthy diet: Diets high in sodium and saturated fats, and low in potassium, significantly contribute to hypertension.
• Excessive alcohol consumption: Drinking more than moderate amounts of alcohol can raise blood pressure over time.
• Tobacco use: Smoking damages blood vessel walls and elevates blood pressure.
• Chronic stress: Prolonged stress may drive temporarily elevated blood pressure and encourage unhealthy coping behaviours.
• Underlying medical conditions: Kidney disease, diabetes, and sleep apnoea are recognised causes of high blood pressure.
• Certain medications: Some over-the-counter drugs, including NSAIDs, decongestants, and oral contraceptives, can raise blood pressure in some individuals.

Symptoms of High Blood Pressure

One of the most concerning aspects of hypertension is the near-total absence of obvious symptoms in most cases. Many people live with high blood pressure for years without realising it, which is why routine blood pressure testing is so important.

When hypertension symptoms do occur, they are typically associated with extremely high blood pressure levels and may include:

• Severe headaches, particularly at the back of the head
• Shortness of breath
• Nosebleeds
• Dizziness or lightheadedness
• Visual disturbances, such as blurred or double vision
• Chest pain or tightness
• Fatigue or confusion

These symptoms are not exclusive to hypertension and can be caused by other conditions. However, if you experience any of these alongside a very high blood pressure reading, seek medical attention immediately.

When to Seek Immediate Medical Attention

Call emergency services or go to your nearest A&E immediately if your blood pressure reads 180/120 mmHg or higher, especially alongside any of the following:

• Severe chest pain
• Sudden severe headache
• Difficulty breathing
• Sudden vision changes
• Difficulty speaking
• Weakness or numbness in the face, arms, or legs

These can indicate a hypertensive crisis, stroke, or heart attack — all of which are medical emergencies.

What are the types of high blood pressure?

There are several recognised types of hypertension, each with different underlying causes and management approaches:

• Primary (essential) hypertension: The most common type, accounting for approximately 90–95% of all cases. It develops gradually over many years with no single identifiable cause, though lifestyle and genetic factors play a major role.
• Secondary hypertension: Caused by an underlying medical condition such as kidney disease, hormonal disorders, thyroid problems, or obstructive sleep apnoea. It tends to appear suddenly and produce higher blood pressure than primary hypertension.
• White coat hypertension: Blood pressure that is consistently elevated in a clinical setting but normal at home, identifiable through ambulatory blood pressure monitoring.
• Masked hypertension: The opposite of white coat hypertension — normal readings in a clinic but elevated blood pressure at home.
• Resistant hypertension: Blood pressure that remains above target despite the use of three or more antihypertensive medications at optimal doses.
• Isolated systolic hypertension: A condition where only the systolic (top) number is elevated, most commonly seen in older adults.

Diagnosing High Blood Pressure: Tests and Procedures

Diagnosing hypertension involves measuring blood pressure on multiple occasions to confirm consistently elevated readings. A high blood pressure test is non-invasive: a healthcare professional wraps an inflatable cuff around your upper arm and records the pressure as the cuff deflates.

To confirm a diagnosis, your doctor may recommend:

• Multiple readings: Taken on different occasions to rule out temporary spikes.
• Ambulatory blood pressure monitoring (ABPM): A portable device worn over 24 hours, recording readings at regular intervals day and night.
• Home blood pressure monitoring: Regular self-monitoring with a validated home device.
• Blood tests: To check kidney function, blood glucose, cholesterol, and electrolytes.
• Urine tests: To detect protein or blood, which may indicate kidney involvement.
• Electrocardiogram (ECG): To assess the heart's response to sustained high blood pressure.
• Echocardiogram: An ultrasound of the heart to evaluate its structure and function.

Blood pressure categories

• Normal blood pressure is a systolic reading of less than 120 mmHg and a diastolic reading of less than 80 mmHg. This is the ideal range for most adults.
• Elevated blood pressure is defined as a systolic reading of 120–129 mmHg and a diastolic reading of less than 80 mmHg. It is not yet hypertension, but indicates an increased risk of developing it without intervention.
• Stage 1 hypertension is a systolic reading of 130–139 mmHg or a diastolic reading of 80–89 mmHg. At this stage, lifestyle changes are typically recommended, and medication may be considered depending on overall cardiovascular risk.
• Stage 2 hypertension is a systolic reading of 140 mmHg or higher, or a diastolic reading of 90 mmHg or higher. This stage usually requires both lifestyle modification and medication to bring blood pressure under control.
• Hypertensive crisis is a systolic reading higher than 180 mmHg and/or a diastolic reading higher than 120 mmHg. This is a medical emergency requiring immediate attention. At this level, there is a serious risk of organ damage, stroke, or heart attack.

Both stage 1 hypertension and stage 2 hypertension require medical assessment and, in many cases, treatment. The category determines the urgency and type of intervention recommended.

Potential Health Risks Associated with Untreated Hypertension

The effects of high blood pressure on the body are wide-ranging and can be severe if left unmanaged. Chronically elevated blood pressure damages the arteries, heart, brain, kidneys, and eyes. Key hypertension risks include:

• Heart attack and coronary artery disease: High blood pressure damages arterial walls, promoting plaque build-up that can block coronary arteries.
• Stroke: Hypertension is one of the leading causes of stroke, either by bursting a blood vessel in the brain or by promoting clot formation.
• Heart failure: The heart must work harder against elevated pressure, leading to enlargement and eventual weakening of the heart muscle.
• Kidney damage: Narrowed blood vessels in the kidneys impair their ability to filter waste, potentially leading to chronic kidney disease.
• Vision loss: Damage to the small blood vessels in the eyes (hypertensive retinopathy) can cause visual impairment or blindness.
• Peripheral artery disease: Reduced blood flow to the limbs can cause pain, cramping, and in severe cases, limb amputation.
• Vascular dementia: Impaired blood flow to the brain over time may contribute to cognitive decline.
• Aneurysm: Elevated pressure can cause arterial walls to bulge and potentially rupture — a potentially fatal complication.

Lifestyle Modifications to Lower Blood Pressure Naturally

For many people with elevated or stage 1 hypertension, lifestyle changes alone can be sufficient to reduce blood pressure naturally to healthy levels. Even for those who require medication, these modifications significantly enhance treatment effectiveness:

• Adopt a heart-healthy diet: The DASH (Dietary Approaches to Stop Hypertension) diet is clinically proven to lower blood pressure. It emphasises fruits, vegetables, whole grains, lean proteins, and low-fat dairy, while limiting sodium, saturated fats, and added sugars.
• Reduce sodium intake: Limiting salt to less than 6g per day (approximately one teaspoon) can meaningfully reduce blood pressure.
• Exercise regularly: At least 150 minutes of moderate-intensity aerobic activity per week — such as brisk walking, cycling, or swimming — can reduce blood pressure by 5–8 mmHg.
• Maintain a healthy weight: Losing even a modest amount of weight, particularly around the abdomen, can substantially lower blood pressure.
• Limit alcohol: Drinking no more than 14 units of alcohol per week, spread across several days, helps keep blood pressure in check.
• Quit smoking: Every cigarette temporarily raises blood pressure. Stopping smoking reduces cardiovascular risk significantly.
• Manage stress: Mindfulness, deep breathing, yoga, and adequate sleep hygiene can all help reduce blood pressure by lowering stress hormone levels.
• Reduce caffeine: In some individuals, caffeine causes a temporary spike in blood pressure. Monitoring your response to caffeinated drinks is advisable.

Medical Treatments for High Blood Pressure

When lifestyle changes are insufficient, or when blood pressure is very high at diagnosis, medical treatment is required. Hypertension treatment is typically long-term, and the goal is to bring blood pressure to a safe level and keep it there.

Medications: Types and How They Work

There are several classes of high blood pressure medicines, and doctors often prescribe a combination to achieve optimal control:

• ACE inhibitors (e.g. ramipril, lisinopril): Relax blood vessels by blocking the production of a hormone that causes them to constrict.
• ARBs — Angiotensin II Receptor Blockers (e.g. losartan, candesartan): Similar in effect to ACE inhibitors, with a different mechanism and fewer side effects for some patients.
• Calcium channel blockers (e.g. amlodipine, felodipine): Relax the muscles of the heart and blood vessel walls to lower blood pressure.
• Thiazide diuretics (e.g. bendroflumethiazide): Help the kidneys remove excess sodium and water, reducing blood volume and pressure.
• Beta-blockers (e.g. atenolol, bisoprolol): Reduce heart rate and the force of contraction, lowering blood pressure. Often used alongside other medications.
• Alpha-blockers and other agents: Used when first-line treatments are insufficient or not tolerated.

It is important to take all prescribed medications as directed and not to stop them without consulting your doctor, even if you feel well. Regular high blood pressure checks allow your doctor to assess whether your treatment plan remains appropriate.

High Blood Pressure in Specific Populations

Hypertension in Older Adults

Blood pressure naturally tends to rise with age, making hypertension extremely common in older adults. Isolated systolic hypertension is particularly prevalent in this group. Treatment must be carefully tailored to avoid excessively low blood pressure (hypotension), which can increase the risk of falls and dizziness. Lifestyle modifications remain important, but medication is often required.

Hypertension in Pregnant Women

High blood pressure during pregnancy requires close monitoring and careful management, as it poses risks to both mother and baby. Gestational hypertension develops after 20 weeks of pregnancy and usually resolves after delivery. Pre-eclampsia is a more serious condition characterised by hypertension and signs of organ damage, including elevated protein in the urine. In severe cases, it can progress to eclampsia, which involves seizures. Certain blood pressure medicines — including ACE inhibitors — are not safe during pregnancy; alternatives such as labetalol and nifedipine are typically prescribed instead.

Hypertension in Children and Adolescents

Although less common, hypertension can occur in children and young people. It is more often secondary to an underlying cause, such as kidney disease or a congenital heart defect. Childhood obesity is an increasingly common contributor to elevated blood pressure in younger populations. Blood pressure levels in children are assessed relative to age, sex, and height using specific paediatric reference charts.

Preventing High Blood Pressure

Prevention is always preferable to treatment. While some risk factors — such as age, family history, and genetics — cannot be changed, many of the most significant contributors to hypertension are modifiable. The following strategies can meaningfully reduce your risk:

• Eat a balanced, low-sodium diet rich in fruits, vegetables, and whole grains.
• Maintain a healthy body weight throughout life.
• Exercise regularly and avoid prolonged periods of sitting.
• Limit alcohol consumption and quit smoking.
• Manage chronic stress through healthy coping strategies.
• Attend regular health check-ups and have your blood pressure measured at least every two years if readings are normal, or more frequently if you are at higher risk.
• Manage underlying health conditions — such as diabetes and kidney disease — that can contribute to high blood pressure.

Early detection through routine high blood pressure checks remains one of the most powerful tools in preventing the long-term complications of hypertension. If you have not had a blood pressure test recently, speak to your GP or visit a pharmacy, where many offer free blood pressure testing services.

Taking proactive steps today — whether through lifestyle changes, medication adherence, or regular monitoring — can significantly reduce your risk of serious cardiovascular events and help you maintain a healthier, longer life. High blood pressure, clinically known as hypertension, is a chronic medical condition in which the force of blood pushing against the walls of the arteries is consistently too high. Over time, this persistent elevated blood pressure can cause significant damage to blood vessels and major organs, increasing the risk of heart disease, stroke, kidney failure, and other serious health complications.