The Connection Between Diabetes and Stroke

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If you have diabetes you are at higher risk for stroke and other cardiovascular diseases. As with many of the health problems associated with diabetes, higher-than-normal blood glucose (blood sugar) levels raise the risks.

High Blood Sugar Levels Raise Stroke Risk

Persistently elevated blood glucose levels contribute to the buildup of plaque in blood vessels. Plaque -- a pasty substance made up of cholesterol, calcium, cellular waste and protein -- sticks to the walls of blood vessels and can interfere with blood flow. This impaired blood flow can lead to stroke.

Your blood sugar level over the past couple of months is indicated by the hemoglobin A1c test. The American Diabetes Association says that people with A1c levels above 7% are nearly three times as likely to have a stroke as people with an A1c level below 5%.

For those with diabetes, the important thing to do when it comes to reducing stroke risk is to keep blood sugars within the target range. Controlling blood glucose levels will help minimize plaque buildup.

What Is a Stroke?

A stroke involves blood vessels and the brain. According to the American Stroke Association, “A stroke occurs when a blood vessel that carries oxygen and nutrients to the brain is either blocked by a clot [ischemic stroke] or bursts [hemorrhagic stroke]. When that happens, part of the brain cannot get the blood (and oxygen) it needs, so it starts to die.”

Strokes happen suddenly and require immediate medical attention. Treatment within 60 minutes of the first symptoms often leads to a good prognosis. If deprived of oxygen for more than a few minutes, brain cells begin to die. The longer the stroke lasts, the greater the damage to the brain.

Symptoms of Stroke

Sudden onset of any of the following warning signs of a stroke warrants an immediate call to emergency medical personnel:

  • Numbness or weakness in one leg, arm or side of the face
  • Difficulty walking or keeping balance, or extreme dizziness
  • Confusion or difficulty talking or understanding others
  • Double vision

Transient ischemic attacks (TIAs) are a form of mini-stroke. The symptoms are the same as for a full-blown stroke, but they don’t last as long -- often only a few minutes to an hour. TIAs are warning signs that a bigger stroke could follow.

Risk Factors for Stroke

A family history of heart disease increases stroke risk, as does being over the age of 55. Other risk factors for stroke include:

  • High Blood Pressure: Elevated blood pressure causes the heart to work harder and is one of the primary risk factors for stroke. Blood pressure readings lower than 130/80 are best.
  • Extra Weight Around the Middle: People with excess weight around the midsection (“apple-shaped”) are at higher risk for stroke. According to the National Institutes of Health, men’s waist measurements should be less than 40 inches and women’s should be less than 35 inches.
  • High cholesterol: So-called “bad” (LDL) cholesterol contributes to plaque buildup. The goal is less than 100 mg/dL (milligrams per deciliter). “Good” (HDL) cholesterol helps remove plaque, so that level should be kept above 40 mg/dL. High triglycerides also lead to more plaque. Those levels should be less than 150 mg/dL.
  • Smoking: Among its many bad effects on health, this habit narrows blood vessels and speeds the process of plaque buildup, giving clots more chance to form.

Ways to Reduce Stroke Risk

The following steps will help reduce the risk for stroke:

  • Good glucose control
  • Controlling blood pressure with exercise or medication
  • Eating a heart-healthy, low-fat diet rich in fruit, vegetables, and whole grains
  • Exercising daily to help lower cholesterol and control blood glucose levels
  • Trying to achieve an ideal body weight
  • Asking a health care professional about beginning an aspirin regimen
  • Quitting smoking
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Article Sources

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  • "Diabetes, Heart Disease, and Stroke." August, 2013. National Diabetes Information Clearinghouse. 7 Sep 2007 National Institute of Diabetes and Digestive and Kidney Disorders
  • "What is Stroke?" American Stroke Association. American Heart Association. Accessed 2/19/2016

  • "Type 2 Diabetes Practice Guidelines." July 1, 2008. National Guideline Clearinghouse.

  • "NINDS Transient Ischemic Attack Information Page." National Institute of Neurological Disorders and Stroke.