By Heidi Moawad, MD |
A stroke may seem like an unpredictable event. And, in large part, it is unpredictable. No one can forecast exactly when a stroke will happen. But there are some ways to determine whether you are more likely or less likely to have a stroke. Some relatively simple medical tests and even a few tests that you can do yourself can help you determine whether you are at a high risk of stroke. Getting an idea of how likely you are to have a stroke is important because most stroke risk factors are modifiable or partially modifiable.
The following tests can help you determine which type of action you need to take to reduce your risk of having a stroke.
When your doctor listens to your heart using a stethoscope, the sounds that your heart makes can help your doctor identify whether you have a problem that involves one of your heart valves or whether you have an irregular rate and rhythm of your heartbeat. Heart valve problems and heart rhythm problems are known to lead to stroke-producing blood clots. Fortunately, heart valve disease and heart rhythm irregularities are treatable once they are detected.
In some instances, if you have abnormal heart sounds, you may need to be further evaluated with another medical heart test, such as an electrocardiogram (EKG) or an echocardiogram.
An EKG monitors your heart rhythm by using small metal discs that are positioned superficially on the skin of the chest. A painless test, an EKG does not involve needles or injections and it does not require you to take any medication.
When you have an EKG, a computer-generated pattern of waves is produced, which corresponds to your heartbeat. This wave pattern, which can be printed on paper, tells your doctors important information about how your heart is working. An abnormal heart rate or an irregular heart rhythm can put you at risk of stroke.
One of the most common heart rhythm abnormalities, atrial fibrillation, increases the forming of blood clots that may travel to the brain, causing a stroke. Atrial fibrillation is not uncommon and it is a treatable heart rhythm abnormality. Sometimes, people who are diagnosed with atrial fibrillation are required to take blood thinners to reduce the chances of having a stroke.
An echocardiogram is not as common as the other tests on this list. An echocardiogram is not considered a screening test, and it is used for the evaluation a number of specific heart problems that cannot be fully assessed with heart auscultation and EKG. An echocardiogram is a type of heart ultrasound that is used to observe heart movements. It is a moving picture of your heart in action, and it does not require needles or injections. An echocardiogram typically takes longer to complete than an EKG. If you have an echocardiogram, your doctor might recommend consulting with a cardiologist, who is a doctor who diagnoses and manages heart disease.
Over 3/4 of individuals who experience a stroke have hypertension, which has long been defined as a blood pressure higher than 140mmHg /90 mmHg.
Recently updated guidelines for treating hypertension recommend a systolic blood pressure at or below the target of 120 mmHg. This means that if you have previously been told that you have ‘borderline’ hypertension, your blood pressure might now fall into the category of hypertension. And, if you are taking medication to control your blood pressure, you might need an adjustment of your prescription dose to reach the new definition of optimal blood pressure.
Hypertension means that your blood pressure is chronically elevated. Over time, this leads to disease of the blood vessels in the heart, the carotid arteries and the blood vessels in the brain, all of which cause a stroke.
Hypertension is a manageable medical condition. Some people are more genetically predisposed to hypertension, and there are some lifestyle factors that contribute to and exacerbate hypertension. Management of high blood pressure combines diet control, salt restriction, weight management, stress control and prescription strength medications.
You have a pair of sizeable arteries, called carotid arteries, in your neck. The carotid arteries deliver blood to your brain. Disease of these arteries leads to the formation of blood clots that can travel to the brain. These blood clots cause strokes by interrupting blood flow to the arteries of the brain. Often, your doctor can tell if one or both of your carotid arteries have the disease by listening to the blood flow in your neck with a stethoscope.
Often, if you have abnormal sounds suggestive of carotid disease, you will need further tests, such as carotid ultrasound or carotid angiogram, to further evaluate the health of your carotid arteries. Sometimes, if the carotid artery disease is extensive, you may need surgical repair to prevent a stroke.
Fat and Cholesterol Levels
Your blood cholesterol and fat levels are easily measured with a simple blood test. Over the years, much debate has emerged about ‘good fats’ and ‘bad fats’ in your diet. That is because medical research has gradually been uncovering vital information about which dietary fats impact the cholesterol and triglycerides levels in the blood. Some people are more predisposed to high fat and cholesterol levels due to genetics. Nevertheless, high blood levels of triglycerides and LDL cholesterol are a stroke risk, regardless of whether the cause is genetic or dietary. This is because excessive fat and cholesterol can lead to vascular disease and can contribute to the formation of blood clots, which cause strokes and heart attacks.
Current guidelines for optimal blood fat and cholesterol levels are:
* Below 150 mg/dL for triglycerides
* Below 100 mg/dL for LDL
* Above 50 mg/dl for HDL
* Below 200 mg/dL for total cholesterol
Find out more about your ideal fat and cholesterol levels and learn more about the current guidelines for fat and cholesterol in your diet. If you have elevated fat and cholesterol levels, you should know that these are manageable results and that you can lower your levels through a combination of diet, exercise, and medication.
Individuals who have diabetes are two to three times more likely to experience a stroke throughout their lifetime. Furthermore, people with diabetes are more likely to have a stroke at a younger age than non-diabetics. There are several tests that are commonly used to measure blood sugar. These tests are used to determine whether you have undiagnosed diabetes or early diabetes.
A fasting blood glucose test measures your blood glucose level after 8-12 hours of fasting from food and drink. Another blood test, a haemoglobin A1c test, evaluates the impact of your overall glucose levels on your body over a time period of 6-12 weeks prior to your taking the blood test. Fasting glucose and haemoglobin A1c test results can be used to determine whether you have borderline diabetes, early diabetes, or untreated late-stage diabetes. Diabetes is a treatable disease that can be managed with diet, medication or both.
This is not so much a ‘test’ as it is determining whether or not you are able to participate in caring for yourself regularly. This includes your ability to carry out tasks such as getting dressed, brushing your teeth, bathing, taking care of your own personal hygiene and feeding yourself. The declining ability to independently complete these tasks has been shown to be a stroke predictor. Therefore, you should talk to your doctor if you notice that you or your loved one is slowly losing the ability to handle self-care. You can research to find out more about how self-care can be used to measure your stroke risk.
One scientific research study from Albert Einstein College of Medicine that looked at the walking speed of 13,000 women found that those who had the slowest walking speed were at a 67% greater risk of stroke than those who had the fastest walking speed. Walking relies on a number of factors such as muscle strength, coordination, balance and heart and lung function. Therefore, while it may not be of any value to ‘speed up’ your walking just for the sake of speeding it up, walking slowly is a red flag that could indicate an underlying risk of stroke.
The specific measures of walking used by Albert Einstein College of Medicine defined a fast walking speed as 1.24 meters per second, average walking speed as 1.06-1.24 meters per second and a slow walking speed as slower than 1.06 meters per second.
Standing on One Leg
Researchers in Japan have published the results of a scientific study that concluded that being able to stand on one leg for longer than 20 seconds is another indicator that can determine a person’s chances of having a stroke. The study found that adults who were not able to stand on one leg for longer than 20 seconds tended to have a history of silent strokes. Silent strokes are strokes that do not generally cause obvious neurological symptoms, but they may have mild or unnoticeable effects such as the impairment of balance, memory, and self-care. Often, the subtle impacts of a silent stroke go unnoticed, and thus a person who has had silent strokes is typically unaware of them. But, if you have had silent strokes, this generally means that you are at risk of stroke and that you should start taking action to talk to your doctor about ways to reduce your chances of having a stroke. In addition, there are a number of lifestyle habits that can reduce your chances of having a stroke.
Sex differences in predictors of ischemic stroke: current perspectives, Alyana A Samai and Sheryl Martin-Schild, Vascular Health and Risk Management, July 2015
Walking speed and risk of incident ischemic stroke among postmenopausal women, McGinn AP, Kaplan RC, Verghese J, Rosenbaum DM, Psaty BM, Baird AE, Lynch JK, Wolf PA, Kooperberg C, Larson JC, Wassertheil-Smoller S, Stroke, 2008