While most strokes still do occur among the elderly, a new study suggests that they are increasing globally among younger people, thanks primarily to the obesity epidemic and the growing incidence of type 2 diabetes and high blood pressure. Stroke remains the second leading cause of death worldwide, right after heart disease.
Researchers looked at data from more than 100 studies performed between 1990 and 2010, and determined that the incidence of stroke has increased by one quarter in people between the ages of 20 and 64, and that these patients account for almost one-third of the total number of strokes. On the plus side, the researchers found that during the 20 years they focused on, death rates from strokes fell by 37 percent in developed countries and 20 percent in developing countries, a positive change they attributed to better diagnosis and treatment. However, in the U.S., the number of strokes has been increasing among the young and middle-aged, even as it has decreased in older people.
Strokes occur when a blood vessel supplying the brain is occluded, often preceded by the buildup of plaque in the carotid arteries, the main arteries in the neck that supply blood to the brain. This plaque buildup is the same as the type that occurs in coronary arteries, where a blood clot in an area already narrowed by plaque can cut off blood flow and increase the risk of a heart attack. A blood clot forming in, traveling through, or blocking a carotid artery (or even the dislodging of carotid plaque that travels toward the brain and blocks its blood supply) can cause a stroke.
The risk factors for stroke include high blood pressure, diabetes, smoking and high cholesterol, all of which impact circulation and vascular health and contribute to plaque and clot formation. A history of atrial fibrillation (a potentially serious abnormal heart rhythm); clotting disorders, and the use of estrogen replacement therapy and birth control pills can also increase risk.
The most important things you can do to lower the risk of stroke are to:
- Control your blood pressure, either through lifestyle changes or medication.
- Get regular exercise (people who exercise consistently have a lower risk of stroke).
- Quit if you are a smoker.
- Limit alcohol intake to no more than one drink per day for women and two drinks per day for men.
- Keep tight control of blood sugar and cholesterol levels if you are a diabetic.
The warning signs of stroke include drooping or numbness on one side of the face including an uneven smile, weakness or numbness in one arm (if one arm drifts down when both are raised), and slurred speech (see if the affected individual correctly repeat a simple sentence like "the sky is blue"). If any of these occurs, call 9-1-1 and have the individual transported to a hospital immediately. Other signs of stroke are sudden numbness or weakness of the leg, arm or face, sudden confusion or trouble understanding speech, sudden trouble seeing in one or both eyes, sudden trouble walking, dizziness, loss of balance or coordination and sudden severe headache with no known cause. Here, too, call 9-1-1 and direct the individual to a hospital.
Andrew Weil, M.D.
Majid Ezzati et al "Global and regional burden of stroke during 1990—2010: findings from the Global Burden of Disease Study 2010," The Lancet, doi:10.1016/S0140-6736(13)61953-4