Healthier habits reduce stroke risk factors
7/13/2013, 6 a.m.
Someone dies of a stroke every four minutes. Those who survive often spend a lifetime of disability and loss of independence. Yet, according to the National Institute of Neurological Disorders and Stroke (NINDS), an arm of the National Institutes of Health, 80 percent of strokes are preventable.
Some risk factors for the condition cannot be controlled. Age, gender, race and family history are unchangeable. Other factors, however, can be modified by medical treatment or avoided altogether.
By far, high blood pressure, or hypertension, the biggest contributor to stroke, is controllable through medications and healthy lifestyles.
NINDS indicates that high blood pressure causes a two- to four-fold increase in the risk of stroke before age 80.
Dr. Natalia S. Rost, associate director of the Acute Stroke Service at Massachusetts General Hospital, agrees. “There is ongoing damage to vessels in untreated high blood pressure,” Rost explained. Health professionals prefer a pressure that is 120/80 or less. “We now know that there is low impact damage even when blood pressure is only slightly higher than it should be,” she said.
This is not good news for African Americans, 40 percent of whom are afflicted. Not only is the condition more severe in blacks than in whites, it develops earlier in life and is less likely to be controlled.
“That creates a perfect storm,” explained Rost. Researchers at the University of Alabama at Birmingham bore that out. They found that in those with uncontrolled hypertension the risk of stroke is three times larger for African Americans than for whites.
The solution, according to Rost, is simple. “Check blood pressure regularly,” she advised. Annually is acceptable, but semi-annually is even better. And if one’s primary care provider is not available, the monitors at the local supermarket or pharmacy will do. But unless blood pressure is perfect, seek medical evaluation and treatment right away.
Diabetes is another modifiable condition closely linked to stroke. Although associated with excessive sugar in the blood, the disease also causes destructive changes in the blood vessels throughout the body, including the brain. What’s worse is that if blood glucose levels are high at the time of stroke, brain damage can be more severe and extensive. Treating diabetes can delay or prohibit the complications that increase the risk of stroke.
Heart disease and high cholesterol are precursors to a brain attack. Excessive “bad” cholesterol is the major cause of narrowing of blood vessels, leading to both heart attack and stroke. One heart defect in particular — atrial fibrillation — is responsible for one in four strokes. Atrial fibrillation is a type of irregular heartbeat in which the upper chambers of the heart quiver instead of contract forcefully. Blood tends to pool then clot, which can result in an ischemic stroke.
Some risk factors of stroke, however, are preventable and under one’s control. Smoking is one example. Most people associate cigarette smoking with cancer, but its damage extends far beyond malignant tumors. The NINDS notes that cigarette smoking causes a roughly two-fold increase in the risk of ischemic (blood clot) stroke and a four-fold increase in the risk of hemorrhagic (bleeding) stroke.