Approximately 75-80% of strokes are of the clotting (ischemic) variety, while the remainder (hemorrhagic strokes) are due to bleeding from broken blood vessels. Sometimes platelets (cells in the blood stream responsible for clotting) become ‘sticky’ and promote clotting. If the blood clots too easily it can result in blood flow blockage and subsequent tissue death in that part of the brain normally nourished by the affected blood vessel. You can reduce the risk of the blockage type strokes by keeping your blood platelets from becoming sticky.
A completed stroke is caused by irreversible brain injury due to the interruption of blood flow. In contrast, a transient ischemic attack (TIA) is a temporary focal neurologic deficit caused by the brief interruption of local cerebral blood flow. Strokes occur in one third of patients who have a TIA.
The duration of a focal neurologic deficit that leads to cerebral infarction has arbitrarily been determined to be 24 hours or greater. Any focal neurologic deficit that resolves completely within 24 hours is considered a TIA. The diagnosis of a TIA indicates that no irreversible neurologic injury has occurred and provides an excellent opportunity to prevent permanent damage.
The first step in the evaluation of a patient with possible TIA is to determine if the event in question actually represents a TIA. Certain conditions should be ruled out before the diagnosis of TIA is made. Excluding other diagnoses reduces the possibility of inappropriately labeling a patient with the diagnosis of cerebrovascular disease and launching into a course of costly and potentially dangerous diagnostic testing.
The symptoms of a TIA depend on the region of the brain that is supplied by the transiently occluded cerebral artery.
If a TIA is recognized, steps can be taken to prevent future ischemic stroke. All TIAs should be promptly investigated because the risk of ischemic stroke is highest soon after a TIA.
Elevated blood pressure increases the risk of stroke substantially. Discontinuing hypertensive medication with a return of high blood pressure significantly increases the risk of stroke, especially for someone under the age of 55. Hypertensives are strongly advised not to discontinue medication permanently unless their blood pressure stays close to the normal range.
One study found that while patients on pressure-lowering medications still faced double the stroke risk of healthy controls, patients who abandoned these medications had nearly five times the risk. They authors speculate that the thinning of the arterial wall that occurs with the use of many antihypertensive drugs (due to lowered pressure) might render the wall more subject to injury from high pressure that may occur when medications are ceased. The stroke risk associated with stopping hypertension medication appears to be even higher – almost eight times higher in patients under the age of 55 years than in older patients. This phenomenon might be explained by the vascular thickening that accompanies aging.
Sometimes symptoms of a stroke are difficult to identify. Unfortunately, the lack of awareness spells disaster. The stroke victim may suffer brain damage when people nearby fail to recognize the symptoms of a stroke. Now doctors say a bystander can recognize a stroke by asking three simple questions:
Ask the individual to SMILE.
Ask him or her to RAISE BOTH ARMS.
Ask the person to SPEAK A SIMPLE SENTENCE (Coherently) (ie. It is sunny out today)
If he or she has trouble with any of these tasks, call 911 immediately and describe the symptoms to the dispatcher.
Signs, symptoms & indicators of Increased Risk of Stroke
Rapid pulse rate
See the link between Increased Risk of Coronary Disease / Heart Attack and Pulse Rate.
Counter Indicators
Slowed pulse rate
See the link between Increased Risk of Coronary Disease / Heart Attack and Pulse Rate.
Having a slight/having a moderate/having a high fever
Fever is a frequent complication early after stroke and in the majority of cases, it can be explained by infection or chemical aspiration pneumonia. In about half of the infected patients, infection was most probably acquired before stroke. Fever was associated with a more severe neurological deficit on admission.
Conditions that suggest Increased Risk of Stroke
Arrhythmias/Dysrhythmias
In atrial fibrillation (AF), the erratic motion of the atria leads to blood stasis which predisposes to blood clots which may travel from the heart to the brain and other areas. Thus, AF is an important risk factor for stroke, the most feared complication of atrial fibrillation. AF may increase mortality up to 2-fold, primarily due to embolic stroke.
Atrial fibrillation is the most common clinically significant cardiac arrhythmia and a major risk factor for ischemic stroke and peripheral embolism. Anticoagulant use reduces this risk.
Recent onset/medium-term/long-term hypertension
Sleep Apnea
There is evidence suggesting that individuals with obstructive sleep apnea may be at increased risk of stroke. Researchers looking at “heavy snorers” say that their increased risk of stroke may be linked to reduced blood flow in the brain during certain stages of sleep.
Risk factors for Increased Risk of Stroke
Stroke in family members
Low Total Cholesterol
Researchers have found that as cholesterol levels drop, the risk of hemorrhagic stroke (accounting for 20% of strokes) increased significantly. A person with a cholesterol level below 180mg/dl had twice the risk of that type of stroke when compared with someone at a level of 230mg/dl.
Anticoagulant Use
Atrial fibrillation is the most common clinically significant cardiac arrhythmia and a major risk factor for ischemic stroke and peripheral embolism. Anticoagulant use reduces this risk.
Hemochromatosis (Iron overload)
According to a study published in Neurology, high iron levels in stroke patients may prompt more severe neurological symptoms and possibly increase brain damage. Elevations of iron may intensify post-stroke neurological problems such as increased weakness, speech and orientation difficulties, and decreased levels of consciousness. Stroke patients with high ferritin concentrations may also have larger areas of the brain damaged due to stroke. High body iron stores may increase free radical production in brain cells, thus prompting stroke progression.
Copper Deficiency
A copper deficiency has been associated with weakening of connective tissue that can be a contributing factor for the development of cerebral aneurysms and hemorrhagic strokes.
EFA (Essential Fatty Acid) Type 3 Requirement
Consuming cold water fish (and probably omega-3 fatty acids) reduced the incidence of stroke in women by 28 percent. This study demonstrated a reduction in clotting type strokes, without an increase in hemorrhagic strokes.
Regular/occasional/history of COX-2 inhibitor use
Animal research suggests that the selectivity of COX-2 inhibitors could create an imbalance that promotes blood clotting and blood vessel constriction. COX-1 makes thromboxane A2, which promotes blood vessel constriction and “stickiness” in blood cells called platelets. COX-2 is the major source of prostacyclin, which helps prevent platelets from clumping and promotes blood vessel dilation. Until further research is completed it may be wise to use COX-2 inhibitors cautiously, if at all, if you are at greater risk of stroke. [Science April 19, 2002;296: pp.539-541]
Moderate/high fruit/vegetable consumption
Moderate/high/low cold water fish consumption
Increased Risk of Stroke suggests the following may be present
Increased Risk of Stroke could instead be
Bell's Palsy
A facial paralysis that has resulted from a stroke is sometimes misdiagnosed as Bell’s palsy.
Recommendations for Increased Risk of Stroke
Taurine
Taurine reduces platelet aggregation, which is how most natural products work in stroke prevention.
Grape Seed Extract / Resveratrol
Previous studies have determined an association between mild-to-moderate red wine consumption with a reduced incidence of cardiovascular, cerebrovascular, and peripheral vascular risk.
Johns Hopkins University School of Medicine (Maryland, USA) researchers investigated the mechanism by which resveratrol, a compound found in the skins and seeds of red grapes, may protect against stroke.
Two hours after feeding mice a single modest dose of resveratrol, the researchers induced an ischemic stroke. Those animals that had preventively ingested the resveratrol suffered significantly less brain damage, as compared to ones that had not been given the compound.
Sylvain Dore, lead researchers of the study, posits that resveratrol increases levels of an enzyme (heme oxygenase) already known to shield nerve cells in the brain from damage. When the stroke hits, the brain is ready to protect itself because of elevated enzyme levels. In mice that lacked the enzyme, the study found, resveratrol had no significant protective effect and their brain cells died after a stroke.
The team concludes that: “The data suggest a potential intracellular pathway by which resveratrol can provide cell/organ resistance against neuropathological conditions.”
Cayenne Pepper (Capsicum frutescens)
Cayenne reduces platelet aggregation (makes the blood less likely to clot) and thus may reduce the risk of clotting strokes.
Vegetarian/Vegan Diet
A low incidence of cerebrovascular disease was associated with geographical regions where fresh fruit and vegetable consumption (increased potassium) was high. [Low fruits and vegetables, high-meat diet increase cerebrovascular event risk. Medical Tribune March 10, 1997:26]
Increased Fruit/Vegetable Consumption
Consuming at least 3 servings per day of fruit and vegetables was associated with reduced risk of stroke and death from stroke, ischemic heart disease and cardiovascular disease in a study of over 9,000 adults, free of cardiovascular disease at the beginning of a 19 year study.[Am J Clin Nutr 2002;76(1): pp.93-99]
Artificial Sweetener Avoidance
While artificially sweetened soft drinks lack calories and thus may be a seemingly attractive alternative to sugar-sweetened beverages, the long-term health consequences of drinking diet soft drinks remains unclear. Hannah Gardener, from the University of Miami Miller School of Medicine (Florida, USA), and colleagues examined the relationship between both diet and regular soft drink consumption and risk of stroke, myocardial infarction (or heart attack), and vascular death. Data were analyzed from 2,564 participants enrolled in the Northern Manhattan Study.
The team found that those subjects who drank diet soft drinks daily were 43% more likely to have suffered a vascular event, as compared to those who drank none, after adjusting for confounding factors. People who drank between one diet soft drink a month and six a week, and those who chose regular soft drinks, were not found to be at increased risks for vascular events. The study authors conclude that: “Daily diet soft drink consumption was associated with several vascular risk factors and with an increased risk for vascular events.”
[Gardener H, Rundek T, Markert M, Wright CB, Elkind MS, Sacco RL. “Diet Soft Drink Consumption is Associated with an Increased Risk of Vascular Events in the Northern Manhattan Study.” J Gen Intern Med., January 27, 2012.]
Increased Fish Consumption
Eating fish, one or more times per month, was associated with a reduced risk of ischemic stroke in a study of 43,671 men aged 40 to 75 years followed for 12 years. No associations were found between fish or long-chain omega-3 polyunsaturated fatty acid intake and risk of hemorrhagic stroke.
The use of fish oil or increased consumption of omega-3 fatty acids should have the same effect. [JAMA 2002;288(24): pp.3130-6]
Caffeine/Coffee Avoidance
Coffee, including decaf, contains significant amounts of Vitamin K which is an important factor for blood coagulation. People at high risk for blood clots, strokes, and heart attacks should avoid coffee and decaf for this reason.
Conventional Drugs / Information
You can increase the chance of getting the preventive effects and decrease the chance of side effects effects of any medicine by choosing and using it wisely. When it comes to using aspirin to lower the risk of heart attack and stroke, choosing and using wisely means knowing the facts and working with your health professional.
There are many reasons to believe that the drug dipyridamole (300mg per day) will be far more effective in the prevention of heart attacks and strokes than aspirin. Moreover, dipyridamole has none of the harmful side effects of aspirin.
Dipyridamole, like aspirin, inhibits platelet adhesion, and thus tends to prevent the vascular thrombosis of heart attacks and strokes. In a trial referencing the poor response to aspirin, Dipyridamole was added to the treatment protocol and the results were outstanding. Over a two-year period, stroke deaths were decreased by 50%, deaths from myocardial infarction decreased by 38% and deaths from cancer by 25%. [ European Stroke Prevention Study, Lancet, December 12, 1987; pp. 1,371-4]
Policosanol/Octacosanol
Policosanol inhibits the formation of clots, and may work synergistically with aspirin in this respect. 75% of strokes are of the clotting kind. In a comparison of aspirin and policosanol, aspirin was better at reducing one type of platelet aggregation (clumping together of blood cells) but policosanol was better at inhibiting another type. Together, policosanol and aspirin worked better than either alone.
Lithium (low dose)
Research in experimental animals with deliberately induced ischemic strokes has shown that lithium reduces the areas of cell death.
Potassium
Potassium, found in fruits and vegetables, has been shown to decrease the incidence of strokes. A low potassium diet increases the risk of stroke. [Neurology 2002;59(3): pp.314-320]
Lecithin / Choline / GPC
Research on GPC’s therapeutic effect in cases of vascular dementia caused by stroke suggests that GPC may promote functional recovery. These studies were uncontrolled so additional research will be necessary to confirm this benefit.
EPA (eicosapentanoic acid)
EPA reduces platelet aggregation and thus helps prevent those strokes that are due to an abnormal clotting tendency.
Essential Fatty Acids
High doses of Omega-3 oils reduce platelet aggregation and thus reduce the abnormal clotting tendency which is seen in 75% of strokes.
Vitamin Folic Acid
A study found that people with a dietary intake of at least 300mcg per day of folic acid reduced their risk of stroke and heart disease by 20% and 13%, respectively, compared with those who consumed less than 136mcg of folic acid per day.
[Stroke 2002;33: pp.1183-9]
Vitamin E
Vitamin E at 300 IU or above reduces platelet aggregation, as do the tocotrienols. It is interesting to note that some doctors report that starting to take large doses of vitamin E immediately after a stroke will encourage a higher level of recovery than without the use of vitamin E. For example, instead of having to use a walker, a patient may become mobile with just a cane. This was based on the work of Dr.s Wilfred and Evan Shute. They believed that vitamin E reduces ischemia commonly experienced in myocardial infarction, stroke and renal failure.
These doctors recommended doses from 400 IU to 8,000 IU daily. The usual dose range was 800 to 1600 IU but they reported that they had given 8,000 IU (about 8 grams) without seeing any toxicity.
Yet, a study reported in the June 15, 1999, issue of the “Annals of Internal Medicine” presented data derived from over 40,000 subjects — male health professionals whose dietary intake, use of vitamin supplements and health status were followed starting in 1986.
The researchers found no difference in risk of stroke between the high vitamin E- and C-consuming subjects and those who consumed lower levels of the two nutrients. Similarly, the researchers found that a higher intake of most of the carotenoids did not decrease the risk in these men of either total stroke or ischemic stroke. Only with respect to lutein (a carotenoid found mainly in dark-green leafy vegetables) did the investigators find a weak trend of decreased risk of stroke with increased intake.
Vitamin B6 (Pyridoxine)
Vitamin B6 at 150-200mg daily reduces platelet aggregation, and thus may help prevent ischemic (clotting type) strokes.
Key
| Weak or unproven link |
| Strong or generally accepted link |
| Proven definite or direct link |
| Strongly counter-indicative |
| May do some good |
| Likely to help |
| Highly recommended |
| May have adverse consequences |
Glossary
Ischemia
Localized tissue anemia due to obstruction of the inflow of arterial blood.
Stroke
A sudden loss of brain function caused by a blockage or rupture of a blood vessel that supplies the brain, characterized by loss of muscular control, complete or partial loss of sensation or consciousness, dizziness, slurred speech, or other symptoms that vary with the extent and severity of the damage to the brain. The most common manifestation is some degree of paralysis, but small strokes may occur without symptoms. Usually caused by arteriosclerosis, it often results in brain damage.
Hypertension
High blood pressure. Hypertension increases the risk of heart attack, stroke, and kidney failure because it adds to the workload of the heart, causing it to enlarge and, over time, to weaken; in addition, it may damage the walls of the arteries.
Aspiration
Inhalation, or removal of fluids or gases from a cavity using suction.
Cardiac
Pertaining to the heart, also, pertaining to the stomach area adjacent to the esophagus.
Arrhythmia
A condition caused by variation in the regular rhythm of the heartbeat. Arrhythmias may cause serious conditions such as shock and congestive heart failure, or even death.
Embolism
Obstruction of a vessel by an abnormal body, usually a detached blood clot.
Anticoagulant
A substance that prevents or delays blood clots (coagulation).
Apnea
Cessation of breathing.
Cholesterol
A waxy, fat-like substance manufactured in the liver and found in all tissues, it facilitates the transport and absorption of fatty acids. In foods, only animal products contain cholesterol. An excess of cholesterol in the bloodstream can contribute to the development of atherosclerosis.
Milligram
(mg): 1/1,000 of a gram by weight.
Iron
An essential mineral. Prevents anemia: as a constituent of hemoglobin, transports oxygen throughout the body. Virtually all of the oxygen used by cells in the life process are brought to the cells by the hemoglobin of red blood cells. Iron is a small but most vital, component of the hemoglobin in 20,000 billion red blood cells, of which 115 million are formed every minute. Heme iron (from meat) is absorbed 10 times more readily than the ferrous or ferric form.
Free Radical
A free radical is an atom or group of atoms that has at least one unpaired electron. Because another element can easily pick up this free electron and cause a chemical reaction, these free radicals can effect dramatic and destructive changes in the body. Free radicals are activated in heated and rancid oils and by radiation in the atmosphere, among other things.
Copper
An essential mineral that is a component of several important enzymes in the body and is essential to good health. Copper is found in all body tissues. Copper deficiency leads to a variety of abnormalities, including anemia, skeletal defects, degeneration of the nervous system, reproductive failure, pronounced cardiovascular lesions, elevated blood cholesterol, impaired immunity and defects in the pigmentation and structure of hair. Copper is involved in iron incorporation into hemoglobin. It is also involved with vitamin C in the formation of collagen and the proper functioning in central nervous system. More than a dozen enzymes have been found to contain copper. The best studied are superoxide dismutase (SOD), cytochrome C oxidase, catalase, dopamine hydroxylase, uricase, tryptophan dioxygenase, lecithinase and other monoamine and diamine oxidases.
Fatty Acids
Chemical chains of carbon, hydrogen, and oxygen atoms that are part of a fat (lipid) and are the major component of triglycerides. Depending on the number and arrangement of these atoms, fatty acids are classified as either saturated, polyunsaturated, or monounsaturated. They are nutritional substances found in nature which include cholesterol, prostaglandins, and stearic, palmitic, linoleic, linolenic, eicosapentanoic (EPA), and decohexanoic acids. Important nutritional lipids include lecithin, choline, gamma-linoleic acid, and inositol.
Bell's Palsy
One-sided facial paralysis of sudden onset and unknown cause. The mechanism is presumed to involve swelling of the nerve due to immune or viral disease, with ischemia and compression of the facial nerve in the narrow confines of its course through the temporal bone.