“The brain nerves which communicate with the entire system are the only medium through which Heaven can communicate to man and affect his inmost life.” –Child Guidance, p. 448

A stroke, which is also known as a cerebrovascular (brain/blood vessel) accident (CVA), is when the blood supply to a part of the brain is interrupted or severely reduced, depriving brain tissue of oxygen and food. Within minutes of decreased blood supply, brain cells begin to die. Eventually, enough brain cells die that it causes a loss of brain function in the area that is affected by the stroke. This loss of brain function manifests itself in many ways, depending which part of the brain is injured and how severely it is injured.  Different areas of our brain control different functions of the body. Therefore, the effects of a stroke differ, depending on what part of the brain was affected. Strokes may cause sudden weakness, paralysis, loss of sensation, difficulty with walking, talking, or seeing.

The results of a stroke are either a temporary or permanent disability, or death. According to the World Health Organization, over 15 million people suffer a stroke worldwide each year. Of these, 5 million die and another 5 million are permanently disabled. Stroke is the leading cause of serious, long-term disability in North America. It is also the second-leading cause of death world-wide after heart disease, accounting for 10 percent of all deaths each year. Cardiovascular disease, which can lead to stroke, kill more people each year than any other reason.

Many people refer to a stroke as a “brain attack,” due to the similarities between a stroke and a heart attack, which causes damage and death to the heart due to lack of blood and oxygen. Like a heart attack, a stroke is a medical emergency. Prompt treatment is crucial. Early action can minimize brain damage and potential complications.

A stroke happens very quickly, and even if you are alert to the warning signs of a stroke, and get the medical help needed, very often it is too late to prevent permanent damage.  People in the developed countries have much quicker access to appropriate medical care, and, with sophisticated medications, can often prevent the stroke from causing any more damage.  The faster that help is received, the better the chances of recovery with a decrease in permanent disability. For every minute delay in treating a stroke, the average person loses 1.9 million brain cells, 13.8 billion synapses (connections between brain cells), and 12 km of axonal fibres (which transmit information from one brain cell to another). Each hour in which treatment does not occur, the brain loses as many brain cells as it does in almost 3.6 years of normal aging.

WHAT CAUSES A LACK OF BLOOD SUPPLY TO THE BRAIN?

There are two main reasons for the blood supply to the brain to be disrupted.  The first reason is known as an “ischemic” attack, from lack of blood and oxygen in the brain due to a clot. The word “ischemic” is defined as “an insufficient supply of blood to a part of the body which is caused by an obstruction or blockage in a blood vessel.” About 80% of strokes are ischemic strokes caused by an abrupt interruption of blood flow to the brain due to a clot. Clots can either form from damage in one of the brain arteries, or from plaque breaking off from damaged arteries in other parts of the body, often from the heart. These clots travel in the bloodstream until they become lodged and cannot travel any further. This usually happens in the small arteries that supply blood to various parts of the brain, which then cuts off the blood supply from that part of the brain, depleting the brain of vital nutrients.

The brain depends on its arteries to bring fresh blood from the heart and lungs. The blood carries oxygen and nutrients to the brain, and takes away carbon dioxide and cellular waste. If an artery is blocked, the brain cells (neurons) cannot make enough energy and will eventually stop working. If the artery remains blocked for more than a few minutes, the brain cells may die. This is why immediate medical treatment is critical.  If an artery is blocked for more than three hours, permanent damage is inevitable.

Many people who have had a stroke have other problems or conditions which put them at higher risk for clots, which then cause strokes. We will learn more about these conditions later in the article.

About 20% of strokes are hemorrhagic, caused by uncontrolled bleeding in the brain. Most hemorrhagic strokes are due to high blood pressure. Many people do not realize that they have high blood pressure as it doesn’t cause any noticeable symptoms, but continual high blood pressure puts added stress on the walls of arteries, which then damages and weakens them. This damage, combined with high pressure levels, can cause blood vessels in the brain to burst, which then causes blood to leak into the brain. The sudden increase in pressure caused by the blood leak within the brain can cause damage to the brain cells surrounding the blood. If the amount of blood increases rapidly, the sudden buildup in pressure can lead to unconsciousness or death. Often, surgery is required to remove the extra blood that has leaked into the brain. Hemorrhagic strokes can occur at any age, whereas the incidence of ischemic strokes tends to increase as the person ages.

TRANSIENT ISCHEMIC ATTACK (TIA)

As the name implies, a TIA is a transient or temporary interruption in blood flow to a part of the brain. The symptoms of a TIA are similar to a stroke but last for a shorter period of time, usually less than an hour, and do not leave “noticeable” permanent damage. This is what people also call a “mini-stroke.” Often, a TIA is a warning sign that the person could suffer a stroke in the near future. A TIA is usually caused by a clot lodging in a blood vessel in the brain, but then dislodges itself almost immediately. Because a TIA is caused by a clot, it is also an indication that the person may have further clots that could break off from damaged vessels and cause another blockage. The risk of another TIA or stroke after a TIA is 10–20% within the following 90 days. People who have had a TIA are five times more likely to have a stroke over the next two years than the general population.

Despite the fact that once a TIA is over, and the person seems back to “normal”, there is a cost. Multiple TIAs over time can and will cause permanent damage. While most TIAs seem small, and the symptoms are temporary, their damage can cause a gradual decline in brain function. Vascular dementia is a form of dementia which is caused by reduced blood flow to the brain over a period of time—usually from a stroke or a series of strokes or TIAs. Symptoms include memory loss, confusion, and difficulty performing every day activities. These symptoms worsen over time as more strokes or TIAs occur.  Vascular dementia is preventable by decreasing risk factors for TIAs or strokes.

RISK FACTORS FOR STROKE

  1. MEDICAL CONDITIONS

Risk factors for stroke include a number of diseases that increase the risk of damage to blood vessels which then in turn can cause clots or weakened areas. Certain medical conditions greatly increase the likelihood of having a stroke.

  1. Previous stroke or “mini-stroke” (TIA). This is a warning sign that you have a health condition which increases your risk for more strokes.
  2. Fatty deposits in your carotid arteries. The carotid arteries are the two arteries on either side of the neck that supply blood to the brain. Narrowing in the arteries decreases the amount of blood flow to the brain. If the arteries become too narrow, blood cells may collect and form clots. Clots can also break off the fatty deposits and go to the brain.
  3. High blood pressure. High blood pressure is the number-one cause for strokes that is preventable; reducing blood pressure levels reduces risk. High blood pressure accounts for 35–50% of stroke risk. Not only can high blood pressure lead to bleeding in the brain, but the damage to blood vessels from high blood pressure is also a leading cause of clot development. World-wide, high blood pressure contributes to more than 12.7 million strokes. Medication and lifestyle changes can lower your blood pressure and reduce your risk.
  4. High blood sugar can increase your risk by damaging your blood vessels. Any damage to blood vessels increases the chances of clot formation. Decrease your risk by managing your diabetes to maintain sugars within normal levels.
  5. Heart disease. Atherosclerosis (hardening of the arteries) causes plaque to build up in blood vessels. This plaque then can break off, and travel to the brain. Diseases of the heart valves, congestive heart failure or a recent heart attack also increases risk of stroke.
  6. Atrial fibrillation (AF), which is an irregular heartbeat, can be caused by specific heart conditions, but it can also occur in otherwise healthy hearts. AF increases stroke risk about five-fold. AF can be genetic also. Medications can be used to treat AF, to reduce stroke risk.
  1. LIFESTYLE CHOICES:
  2. Obesity. Being obese is now considered a disease because of all the health complications that come along with being over weight. Obesity rates are climbing in all countries, with some developed countries having up to one-third of the population considered obese. Obesity causes increases in heart disease, diabetes, high blood pressure, elevated cholesterol and fat levels, all conditions that raise stroke risk.
  3. Elevated cholesterol and elevated triglycerides (fats) levels in your blood. Elevations in these levels are directly connected to one’s diet. Reducing your dietary intake of saturated fats and cholesterol may help reduce your risk of a stroke.
  4. Physical inactivity. A sedentary lifestyle, lacking regular exercise can contribute to heart disease which may lead to stroke. Recommendations are that adults get at least 150 minutes of moderate or 75 minutes of vigorous physical activity a week.
  5. Smoking and excessive alcohol intake. As Reformers, these are not risk factors that we typically have problems with, but when we talk with those who we witness to, health teaching as to tobacco and alcohol use and their relationship to strokes can be done. Smokers have twice the risk of having a stroke than someone who has never smoked. However, even if someone has smoked for years, risk is lowered as soon as a person quits. Alcohol contributes to diseases that affect the circulation of the blood, such as high blood pressure, diabetes, elevation of cholesterol, and atrial fibrillation.

Reducing risk of stroke depends on how willing someone is in making changes to these lifestyle choices.

  1. UNCONTROLLABLE RISK FACTORS:

Despite knowledge of risk factors, decreasing those risks with avoidance of harmful substances, making lifestyle changes, and managing disease, a stroke is still not 100% preventable. There are also a number of risk factors that are uncontrollable which also increase stroke risk. These include:

  1. 1. Increasing age. Nearly three-quarters of all strokes occur in people over the age of 65. The risk of having a stroke more than doubles each decade after the age of 55. However, strokes can occur at any age, but with less frequency at younger ages.
  2. Male sex. Men and women both have strokes but stroke incidence is higher in men than women at younger ages. On a yearly basis, more women than men have strokes, but it is because stroke risk increases with age, and women live longer than men.
  3. Heredity and ethnicity. Strokes are more common in people whose close relatives have had a stroke at an early age. African-Americans and Hispanic Americans are at higher risk than white Americans. This may be due in part to a predisposition to high blood pressure and dietary differences.

Overall, strokes are decreasing in the developed world with greater focus on prevention, but it is no longer a disease that affects only the rich, developed world. Stroke risk is increasing in developing countries because of increased personal wealth, with related problems such as increases in obesity and diabetes.

WARNING SIGNS OF A STROKE:

In order to receive medical treatment as soon as possible, everyone should know about the warning signs of a stroke, to recognize it in yourself or others.

WEAKNESS:

Sudden loss of strength or numbness of the face, arm, or leg, especially on one side of the body.

TROUBLE SPEAKING:

Sudden confusion, or sudden difficulty with speaking or understanding speech.

VISION PROBLEMS:

Sudden trouble with vision, (blurred, double vision) in one or both eyes.

DIZZINESS:

Sudden trouble walking, dizziness, loss of balance or coordination, especially if other symptoms also occur.

HEADACHE:

Sudden, severe headache and unusual headache with no known cause.

The signs of a stroke depend on the side of the brain that’s affected, the part of the brain affected, and how severely the brain is injured. Therefore, each person may have different stroke warning signs. Every one of these symptoms indicate a medical emergency, EVEN IF TEMPORARY; they could be an important warning that requires prompt medical attention.

If you or someone you know is having any of these signs, CALL 911 immediately (in North America—other countries may have different emergency numbers) and seek medical help immediately.

If you have ever had a stroke or experience any of the warning signs of a stroke, it is very important that you work with your doctor to determine the most likely cause of the problem and the best course of treatment for you. Treatment of disease, and changes in lifestyle can reduce the risk of a recurrence.