Risk Factors for Stroke
A risk factor is something that increases your likelihood of getting a disease or condition.It is possible to have a stroke without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of having a stroke. If you have a number of risk factors, ask your doctor what you can do to reduce your risk.Hypertension is the leading risk factor for stroke. Blood pressure is the force of blood on walls of arteries. High blood pressure is when this pressure is higher than expected over a prolonged period of time. Normal blood pressure is in the range of 120/80 mm Hg. Hypertension is defined as blood pressure 140/90 mm Hg. If you have diabetes or chronic kidney disease, it is defined as 130/80 mm Hg. Hypertension causes turbulent blood flow that can damage blood vessels walls and overtime causes them to weaken. If you have hypertension and are not keeping your blood pressure in a specific target range, you have an increased risk of having a stroke. Hypertension has no symptoms, so it is important to have your blood pressure checked regularly.Other risk factors can also be modified through lifestyle changes while other can not be reduced but are important to know:
Factors That Can Be Modified or ChangedSmokingSmoking is a major contributing factor to stroke. Smoking can:
- Irritates and narrows blood vessels which can narrow blood vessel and decrease blood flow
- Contributes to the build up of arterial plaque
- Raises heart rate and blood pressure which can place extra pressure on weakened blood vessel walls
Risk Factors Specific to WomenThere are risk factors that are unique to women. They may be influenced by conditions and/or treatments. In some cases, it may lead to an increased risk of blood vessel damage or blood clots that can interfere with blood flow to the brain, leading to a stroke. These include:
- History of preeclampsia
- Oral contraceptive use
- Migraine with aura (visual disturbances)
- Long-term use of hormone replacement therapy (HRT), which is common during and after menopause
Medical ConditionsCardiovascular Diseases Cardiovascular diseases are major contributors to stroke. Many chronic conditions, such as coronary artery disease or atrial fibrillation , affect heart function, making it difficult to meet the body's demands. Long-term problems cause damage to blood vessels, increasing the risk of blockage (ischemic stroke) or bleeding (hemorrhagic stroke). Some cardiovascular issues include:
- Transient ischemic attacks (TIA)—Sometimes referred to as mini-strokes, TIAs occur when a blood flow is temporarily reduced by narrowing or blockage of blood vessels that supply the brain. The situation usually corrects itself within 24 hours. TIAs are serious and often serve as a warning for a future major stroke.
- Brain aneurysm —An outpouching of a blood vessel wall in the brain that form in areas where the artery wall is weak or thin. The bulging, blood-filled pocket can put pressure on parts of the brain, or in some cases, burst.
- Ateriovenous malformations (AVM)—A rare condition marked by abnormal connections that occur between arteries and veins. Instead of an artery supplying an area of the brain with blood, it is connected directly to a vein that takes it away, bypassing the brain tissue that needs it.
- Vasculitis —Inflammation of the blood vessels. Inflammation over time may damage blood vessels, which in turn may bleed or burst.
- Silent stroke —Brain tissue damage found incidentally during imaging tests may indicate areas where previous strokes occurred. Silent strokes can be a warning for future stroke.
- Previous heart attack or stroke
Factors That Cannot Be ChangedAgeBrain function normally decreases as we age. This decrease is generally not enough to cause problems, but can increase the risk of developing cardiovascular disease, which can lead to a stroke. Some changes include stiffer blood vessels, small breaks in blood vessels, and minor cognitive and memory loss.GenderThe risk of stroke increases as you age. Although men are more likely to have a stroke at a younger age, women overall tend to have more strokes and die from them. This may be due to risk factors that are unique to women in combination with standard ones.Genetics and EthnicityHaving family members that have had a stroke or history of cardiovascular disease increases your risk as well. You are also at a higher risk if you have certain genetic abnormalities. For example, your blood may have a tendency to clot, which can increase the risk of narrowed or blocked arteries.In general, African Americans have a higher incidence of hypertension than Caucasians and, therefore, a higher risk of having a stroke. Stroke risk is also higher among American Indians and Native Alaskans.
Controllable risk factors—tobacco use & smoking. National Stroke Association website. Available at: http://www.stroke.org/site/PageServer?pagename=Smoking. Accessed June 12, 2014.
Esse K, Fossati-Bellani M, et al. Epidemic of illicit drug use, mechanisms of action/addiction and stroke as a health hazard. Brain Behav. 2011;1(1):44-54.
Furie KL, Kasner SE, et al. Guidelines for the Prevention of Stroke in Patients With Stroke or Transient Ischemic Attack: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke. 2011;42(1):227-276. Available at: http://stroke.ahajournals.org/content/early/2010/10/21/STR.0b013e3181f7d043.full.pdf. Accessed June 16, 2014.
Risk factors for stroke or transient ischemic attack. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated June 2, 2014. Accessed June 12, 2014.
Who is at risk for a stroke? National Heart, Lung, and Blood Institute website. Available at: http://www.nhlbi.nih.gov/health/health-topics/topics/stroke/atrisk.html. Updated March 26, 2014. Accessed June 12, 2014.
12/16/2008 DynaMed's Systematic Literature Surveillance http://www.ebscohost.com/dynamed: Farquhar C, Marjoribanks J, Lethaby A, Suckling J, Lamberts Q. Long term hormone therapy for perimenopausal and postmenopausal women. Cochrane Database Syst Rev. 2008;CD004143.
10/23/2009 DynaMed Systematic Literature Surveillance http://www.ebscohost.com/dynamed: Lin HJ, Lee BC, Ho YL, et al. Postprandial glucose improves the risk prediction of cardiovascular death beyond the metabolic syndrome in the nondiabetic population. Diabetes Care. 2009;32:1721-1726.
6/2/2014 DynaMed's Systematic Literature Surveillance http://www.ebscohost.com/dynamed: Myint PK, Cleark AB, et al. Bone mineral density and incidence of stroke: European prospective investigation into cancer-norfolk population-based study, systemic review, and meta-analysis. Stroke. 2014 Feb;45(2):373-82.
6/2/2014 DynaMed's Systematic Literature Surveillance http://www.ebscohost.com/dynamed: Imfeld P, Bodmer M, et al. Risk of incident stroke in patients with Alzheimer disease or vascular dementia. Neurology. 2013 Sep 3;81(10):910-919.
6/18/2014 DynaMed's Systematic Literature Surveillance http://www.ebscohost.com/dynamed: Bushnell C, McCullough LD, et al. Guidelines for the prevention of stroke in women: a statement for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2014;45(5):1545-1588. Available at: http://stroke.ahajournals.org/content/early/2014/02/06/01.str.0000442009.06663.48.full.pdf. Accessed June 19, 2014.
- Reviewer: Rimas Lukas, MD
- Review Date: 12/2014
- Update Date: 12/20/2014
Many medical groups felt that early exposure to certain foods like peanuts increased a child's risk of developing food allergies. However, newer research including this trial suggest that early exposure may actually decrease the risk of developing food allergies.
Breastfeeding May Decrease the Risk of Childhood Obesity
Tonsillectomy May Reduce Number of Sore Throat Days in Children
Research Review Finds Little Support for Nearly Half of Medical Talk Show Recommendations