Hypertensive Crisis: Stroke Risk And Prevention

Hypertensive crisis, defined as an increase in systolic blood pressure beyond 179mmHg or diastolic blood pressure beyond 109mmHg, can cause end-organ damage, with the brain being an early target. High blood pressure damages arteries throughout the body, creating conditions that can make arteries burst or clog easily. Weakened or blocked arteries in the brain increase the risk of stroke. Hypertension accelerates the arteriosclerotic process, increasing the likelihood of cerebral lesions related to stenosis and embolism originating from large extracranial vessels, the aortic arch, and the heart.

High blood pressure and the risk of stroke

High blood pressure, or hypertension, is a condition in which blood flows with too much force, exerting excess pressure on the arteries. This pressure stretches the arteries beyond their healthy limit, causing small tears. Over time, high blood pressure damages arteries throughout the body, creating conditions that make arteries more susceptible to bursting or clogging. Weakened or blocked arteries in the brain significantly increase the risk of stroke.

How High Blood Pressure Causes Strokes

High blood pressure can lead to stroke in two main ways:

• Strokes due to a clot (ischemic stroke): High blood pressure damages blood vessels by making them narrower and stiffer, leading to a build-up of fatty material. This process is called atherosclerosis. Clots can form on these areas of fatty material, and if a clot travels to the brain, it causes an ischemic stroke or transient ischemic attack (TIA or mini-stroke). Ischemic strokes account for most strokes.
• Strokes due to bleeding in or around the brain (haemorrhagic stroke): High blood pressure can damage and weaken blood vessels inside the brain, making them more prone to rupturing and causing bleeding in the brain, resulting in a haemorrhagic stroke. Haemorrhagic strokes are less common but are often associated with high blood pressure.

Reducing the Risk of Stroke

Managing high blood pressure is critical to reducing the risk of stroke. Here are some ways to help manage high blood pressure:

• Eat a healthy diet, including reducing salt intake.
• Engage in regular physical activity and maintain a healthy weight.
• Avoid tobacco smoke.
• Take prescribed medication.
• Limit alcohol consumption.

Hypertension and the brain

Hypertension, or high blood pressure, is a leading cause of stroke, which in turn is a leading cause of death and severe, long-term disability. Strokes occur when a blood vessel to the brain is narrowed or blocked by a clot (ischemic stroke) or bursts (hemorrhagic stroke). When this happens, the brain is deprived of the blood and oxygen it needs, causing brain cells to die. As the brain controls movement, thought, language, memory, and vision, a stroke can affect all of these functions, and may even cause paralysis or death.

High blood pressure damages arteries throughout the body, creating conditions that make arteries more likely to burst or clog. Weakened or blocked arteries in the brain create a much higher risk for stroke, which is why managing high blood pressure is critical to reducing the risk of stroke.

Intracranial hypertension (IH) is a build-up of pressure around the brain, which can put pressure on the optic nerve, causing vision changes, headaches, or temporary blindness. It can happen suddenly, for example, as the result of a severe head injury, stroke, or ruptured brain aneurysm. It can also be caused by conditions that affect the brain, such as a brain abscess, brain tumour, meningitis, or encephalitis. In some cases, there is no obvious cause, and this is known as idiopathic intracranial hypertension.

Idiopathic intracranial hypertension is more common in women, especially in their 20s and 30s, and is linked to weight gain. It is treated by addressing the underlying causes, such as losing weight, stopping certain medications, and taking diuretics to remove excess fluid from the body. In more severe cases, surgery may be required to relieve pressure on the optic nerve and allow fluid to drain away.

Hypertensive crisis and the body

Hypertensive crisis is defined as an increase in systolic blood pressure >179 mmHg or diastolic blood pressure >109 mmHg. It typically causes end-organ damage, with the brain being an early target. The brain is affected by hypertensive crisis in the following ways:

Endothelial Damage

Hypertension increases the stress on the endothelium, which can increase permeability over the blood-brain barrier and lead to local or multifocal brain oedema. Endothelial damage can also alter blood cell-endothelium interaction, leading to local thrombi formation and ischaemic lesions.

Fibrinoid Necrosis

Fibrinoid necrosis can cause lacunar infarcts through focal stenosis and occlusions.

Degenerative Changes in Smooth Muscle Cells and Endothelium

Degenerative changes in smooth muscle cells and endothelium can predispose individuals to intracerebral haemorrhages.

Acceleration of the Arteriosclerotic Process

Hypertension accelerates the arteriosclerotic process, increasing the likelihood of cerebral lesions related to stenosis and embolism originating from large extracranial vessels, the aortic arch, and the heart.

Adaptive Structural Changes in the Resistance Vessels

Adaptive structural changes in the resistance vessels reduce vessel wall tension but increase peripheral vascular resistance. This may compromise the collateral circulation and enhance the risk of ischaemic events in connection with episodes of hypotension or distal to a stenosis.

Overall, the effects of hypertensive crisis on the body can lead to stroke, with the brain being particularly susceptible to damage from high blood pressure.

How to reduce high blood pressure

Hypertensive crisis, or dangerously high blood pressure, can lead to a stroke. High blood pressure damages arteries throughout the body, creating conditions that cause arteries to burst or clog easily. Weakened or blocked arteries in the brain significantly increase the risk of a stroke. Therefore, managing high blood pressure is critical to reducing the risk of a stroke.

Eat a healthy, well-balanced diet

Eat foods that are lower in fat, sodium (salt), and increase your consumption of potassium, fruits, vegetables, and whole grains. The DASH eating plan is an example of a diet that can help lower blood pressure.

Get regular physical activity

Regular physical activity can help you maintain a healthy weight and lower your blood pressure. It can also be a stress management technique, which is another way to lower high blood pressure.

Maintain a healthy weight

Being overweight or obese increases your risk of high blood pressure. Maintaining a healthy weight can help control high blood pressure and reduce your risk of other health problems.

Limit alcohol consumption

Drinking too much alcohol can raise your blood pressure and also leads to weight gain.

Quit smoking

Cigarette smoking raises your blood pressure and puts you at a higher risk of a heart attack and stroke.

Manage stress

Learning how to relax and manage stress can improve your emotional and physical health and lower high blood pressure. Stress management techniques include exercising, listening to music, focusing on something calm or peaceful, and meditating.

Get enough high-quality sleep

A good night's rest can help to lower high blood pressure.

High blood pressure as a silent killer

High blood pressure, or hypertension, is often referred to as "the silent killer" because it frequently goes undetected and can lead to severe health complications and even death. This is because most people with high blood pressure do not experience any noticeable symptoms. Many people are unaware they have this condition until they suffer a major health event, such as a heart attack or stroke.

High blood pressure is a serious medical condition where the blood vessels push against artery walls at a higher rate than normal. This extra force can damage arteries throughout the body, creating conditions that make them more susceptible to bursting or clogging. When this occurs in the brain, it can result in a stroke, which is a leading cause of death and severe, long-term disability. Weakened or blocked arteries in the brain significantly increase the risk of stroke, which is why managing high blood pressure is critical to reducing the chances of this life-threatening event.

The only way to truly know if you have high blood pressure is to get it tested. Early detection is crucial as it can help prevent or delay the serious health consequences associated with untreated hypertension. If left untreated, high blood pressure can increase the risk of heart attack, stroke, brain aneurysm, heart failure, kidney disease, clogged arteries, and even dementia. It can also lead to sexual dysfunction and vision problems, including blindness.

To manage high blood pressure, lifestyle changes are often recommended, such as decreasing salt and alcohol intake, losing weight if necessary, stopping smoking, and engaging in regular exercise. In addition, medication may be prescribed to help lower blood pressure and improve health outcomes. It is important to note that high blood pressure is usually a lifelong condition, and controlling it should be part of a healthy living plan.

Frequently asked questions