Stroke: Risk Factor Management

Authored by MCN Neurologists

The most common type of stroke is ischemic stroke, which is a blockage of an intracranial artery, thereby depriving a portion of the brain from blood, oxygen, nutrients, etc.  The same disease of the arteries affects both the heart and the brain.  Whereas blocked arteries in the heart lead to a heart attack, in the brain, when the arteries plug, or occlude, the portion of the brain dependent on that blood supply dies and the damage is called a stroke.  Often there is little warning and the damage can be severe. The best management of a stroke is before it occurs to prevent the damage, but how is this done?  We all have a predilection for atherosclerotic disease, commonly referred to as “hardening of the arteries.” It is in our human genome and varies from family to family.  Autopsy studies during WWII found some atherosclerotic disease in individuals as young as 20.  The disease is also affected by aging, for the risk of stroke doubles for each decade beyond the age of 50!  Furthermore, stroke occurs more commonly in men than women and more often in African Americans than Caucasians.

Management of Stroke Risk Factors

Though we have no control over our genetics, race, gender or impact of aging, there are accompanying medical conditions common to us all which are known to accelerate the naturally occurring atherosclerotic disease process.  Each of these conditions can be modified through medical means and, when successfully accomplished, greatly reduce the risk of both stroke and heart attack.  There are other medical conditions which contribute to the likelihood of stroke as well, requiring medical treatment to reduce their impact on stroke.

These conditions include hypertension, diabetes, elevated lipids (cholesterol), smoking, obesity, cardiac conditions, peripheral vascular disease and a sedentary lifestyle. Some of these issues are lifestyle related and some are medical conditions.  Nonetheless, attention to these issues is essential for reduction in stroke risk, either before the stroke or after the initial event, but hopefully before major injury occurs!

Hypertension is perhaps the most common and potent cause of arterial injury.  At present, the values of 130/70 are recognized by the American Stroke Association as being the upper limits of normal.  Any greater numbers, either systolic or diastolic, increase stroke risk as much as 6 times.  Although asymptomatic and perhaps under-treated, it is easily managed by all physicians and should be treated aggressively until controlled.  It is easily monitored at home with the purchase of an electronic BP cuff, and the readings one obtains and provides to one’s physician make it easy for them to prescribe and guide us.

Diabetes is increasingly common given the rates of obesity now recognized in the U.S.  Whether insulin dependent, oral medication controlled or simply diet controlled, it is clearly a mistake to take the disease lightly.  The risk of heart disease and stroke is greatly increased in the presence of diabetes, and is reduced when the illness is well controlled and of course the converse is true.

Elevated Lipids are also important.  In the 1970’s the “normal” cholesterol level in the U.S. was 240.  We now know this number is far from normal and was merely “average.”  Thus, at that time, the average American was destined for a heart attack or stroke.  At present, the upper limit of normal for total cholesterol is 200.  After stroke, we often strive to get total cholesterol below 170.  Some researchers feel even that number is too high.  They recommend the lower the better.
Also, the LDL cholesterol fraction is important independent of the total cholesterol number.  We seek <100 for starters and after stroke we prefer this be <70.  It is also important to have the “good” cholesterol (HDL) level higher than 60, though we have few means at our disposal to control this number.
Elevated triglycerides have also been implicated in the generation of atherosclerosis.  Diet, exercise, supplements and medication are all useful in lowering these numbers and often all need to be part of the program to avoid stroke.

Cardiac Conditions are often associated with stroke.  In particular, Atrial Fibrillation, Dilated Cardiomyopathy (poorly contracting heart muscle from any cause) and Atherosclerotic Heart Disease leave the heart less efficient at pumping blood, perhaps causing stagnation of blood flow and permitting clots to form, which are later pumped out of the heart and often find their way to the brain.  All of these conditions are modifiable with proper medical attention and anticoagulation.

Peripheral Vascular Disease is the same condition of the arteries in the rest of the body which occurs in the heart and brain.  The presence of this condition implies similar blockage of vessels in the brain and also to the brain.  The carotid arteries, which are the direct blood flow to most of the brain, are noted in the anterior portion of the neck.  When the carotids plug, stroke is imminent and aggressive medical intervention is required, sometimes even surgery.  Ultrasound screening is effective in recognizing this condition.

Lifestyle Choices (smoking, exercise, obesity) play a major role in the acceleration of vascular disease. Each of these issues has an impact on one’s blood pressure, sugar readings and cholesterol, but also have a very significant independent role in the generation of atherosclerosis.  It is easier to maintain a self-indulgent approach towards these issues and hope that modern medicine can rectify any troubles one creates for one’s self, but it is certainly short-sighted to have this attitude.  Perhaps it is just this attitude which represents the single greatest reason Americans are not healthy despite the vast amount of money we spend on our healthcare compared to the rest of the civilized world without recognizing commensurate benefit.  No matter how much we increase our spending on healthcare, without starting to focus on preventive trends we will not improve our situation.

In summary, simple recognition and attention to one’s risk factors, irrespective of one’s family history or age, can make a major difference in the quality and length of life if stroke injury is less common.  By becoming responsible for our own habits and working with our physicians on simple measurements and controls of these risk factors, we all can make a substantial contribution to the reduction of heart disease and stroke.

For further information about Stroke Risk Factor Management, click on the following links:

www.strokeassociation.org (American Stroke Association)
www.strokemn.org (Minnesota Stroke Association)

Dr. Irfan Altafullah discusses stroke signs and symptoms with Fox 9 News:

          Stroke Awareness – May 2014

          Stroke Signs and Symptoms – May 2014

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