Once again we thank the American Heart Association our experts for information.
The warning signals of stroke are:
- Sudden weakness or numbness of the face, arm or leg on one side of the body.
- Sudden dimness or loss of vision, particularly in only one side.
- Loss of speech, or trouble talking or understanding speech.
- Sudden severe headaches with no known cause.
- Unexplained dizziness, unsteadiness or sudden falls, especially with any of the other symptoms.
If you notice one or more of these symptoms, don't wait. See a doctor or get to an Emergency room right away.
About 10% of stokes are preceded by little strokes or transient ischemic attacks, TIAs, However, of those who've had one or more TIAs, about 36% will later have a stroke. A person who's had one or more TIAs is 9.5 times likely to have a stroke than someone of the same age and sex who hasn't. Thus, TIAs are extremely important stroke warning signs. TIAs are more useful for predicting if a stroke will occur rather than when it will happen. They can occur days, weeks or even months before a major stroke. In about 50% of the cases the stroke occurs within one year of the TIA; in about 20% of the cases, within one month.
TIAs occur when a blood clot temporarily clogs an artery, and part of the brain doesn't get the blood it needs. The symptoms occur rapidly and last a relatively short time. More than 75% of TIAs last less than 5 minutes. The average is about a minute, although some last several hours. By definition, TIAs can last up to several to- but not over- 24 hours, although this is very unusual. Unlike stroke, when a TIA is over, people return to normal.
The usual TIA symptoms are very similar to those of stroke.
They are:
- temporary weakness, clumsiness or loss of feeling in an arm, leg or the side of the face on one side of the body ( or some combination of these)
- temporary dimness or loss of vision. particularly in one eye (also often in combination with other symptoms)
- temporary loss of speech or difficulty in understanding speech, particularly with a right-side weakness, and sometimes dizziness, double vision and staggering occur.
The short duration of these symptoms and lack of permanent damage is the main distinction between TIA and stroke.
Although TIAs signal only about 10% of strokes, they are very strong predictors of stroke risk. They should never be ignored! Get Medical attention immediately! A doctor should determine if a TIA or stroke has occurred. or if it's another medical problem with similar symptoms (seizure, migraine, or general medical or cardiac condition). Prompt medical or surgical attention to these symptoms could prevent a fatal or disabling stroke from occurring.
When stroke occurs, there can be severe losses in mental and bodily functions- if not death. That's why preventing stroke is so important. The best way to prevent stroke is to reduce the risk factors. Some factors that increase the risk are hereditary. Others are a function of natural processes. Others result from lifestyle. Factors resulting from heredity or natural processes can't be changed, but environmental factors can be modified with a doctor's help.
Risk factors that can be treated are:
High Blood Pressure--Hypertension is the most important risk factor for stroke. In fact, stroke risk varies directly with blood pressure. Hypertension afflicts about one in four American adults, both men and women, of all ages. Controlling high blood pressure reduces the risk stroke significantly. Often blood pressure can be controlled by eating a healthier diet and maintaining proper weight, Drugs that control blood pressure are also available. Many experts believe that the death rate from stoke has declined over the past decade is due to better control of hypertension.
Heart Disease-Independent of hypertension, people with heart disease have more than twice the risk of stroke than people with normally functioning hearts. The four major controllable risk factors for heart attacks are cigarette/ tobacco, high blood cholesterol, high blood pressure, and physical inactivity. Controlling these factors reduces the risk of heart disease and thus the risk of stroke.
Cigarette Smoking--Inhaling cigarette smoke produces a number of effects damaging to the cardiovascular system. Nicotine in tobacco increases blood pressure. Carbon monoxide reduces the amount of oxygen in the blood and therefore the amount it can supply to the body. Cigarette smoke also causes the platelets in the blood to become sticky and cluster, shortens platelet survival, decreases clotting time and increases blood thickness.
TIAs--Only about 10% of strokes are preceded by TIAs, nevertheless, they are extremely important predictors of stroke and are usually treated with drugs that inhibit clots from forming.
High Red Blood Cell Count--High red blood cell count thickens the blood and makes clotting more likely. This condition is treated by blood thinners.
Risk factors that can't be changed:
Seven risk factors for stroke can't be changed. These are: 1) increasing age, 2) being male (19% higher for men over women), 3) race (African-Americans have more than a 60% greater risk of death and disability form stoke than do whites), 4) diabetes mellitus, 5) prior stroke, 6) heredity, and 7) asymptotic carotid bruit (bruit is an abnormal sound when a stethoscope is placed on a artery, in this case the carotid artery).
Other less-well-documented risk factors include: 1) living in the Southeastern US-states of Alabama, Arkansas, Georgia, Indiana, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Virginia., 2) Season and climate, meaning that stoke deaths occur more often in extreme temperatures, 3) Excessive alcohol intake, and 4) intravenous drug abuse and cocaine abuse.
Secondary risk factors, that is factors that affect the risk of stoke indirectly by increasing the risk of heart disease (which is a primary risk factor for stroke) are: 1) elevated blood cholesterol and lipids, 2) physical inactivity, and 3) obesity.
One final note to take away with you. The 10% of the population in whom one- third of all strokes occur have a set of five risk factors. These are: 1) high blood pressure, 2) elevated blood cholesterol, 3) abnormal glucose tolerance, 4) cigarette smoking and 5) left ventricular hypertrophy (over-development of the left side of the heart). These people need to be followed by physicians closely.
Next month we will be looking at how a stroke is diagnosed and treatment for stoke.
