Age and stroke
Age, sex, and genetics are 3 risk factors in the development of stroke that cannot currently be changed. In the future, however, we may be able to identify and alter genes in order to reduce some types of genetic risk for stroke. For the time being, your best bet for lowering your risk of stroke is to prevent some of the conditions that lead to strokes.
The older you are the higher your risk for stroke. Because women tend to live longer than men, there is a higher potential for stroke in women older than 80. Plaque buildup in the blood vessels leading to the brain is the primary cause of stroke from the ages of 60 to 80. After the age of 80, blood clots and cerebral hemorrhages become more common causes of stroke.
In young individuals between 18 and 50, the mechanisms of stroke are more diverse. Worldwide, stroke in young adults is increasing. This poses an economical challenge both because of the associated high health-care costs and loss of productivity. In addition to plaque build-up in blood vessels, less common causes of stroke in the young include genetic disorders, illicit drug use, use of oral contraceptives in women, pregnancy, tears in arteries feeding the brain, blood clotting disorders, migraine, and a congenital hole between the upper chambers of the heart. Although less common conditions can cause strokes in the young, more traditional risks such as high blood pressure, diabetes mellitus, smoking, low physical activity, obesity, and plaque build-up cause almost 80% of all ischemic strokes in young adults.
Drugs such as cannabis, opioids, ecstasy, lysergic acid diethylamide (LSD), amphetamines, and cocaine are associated with strokes due to their effects on the cardiovascular system. They can cause a stroke by increasing the risk of blood clots, cerebral hemorrhages, inflammation of the arteries (vasculitis), reversible constriction of blood vessels in the brain, and accelerated plaque development.
Pregnancy is most likely to cause stroke from the 3rd trimester to 6 weeks post-partum. Strokes related to pregnancy are often caused by blood clots formed elsewhere in the body due to excessive blood clotting.
The role of migraine headaches in stroke is still unclear. Multiple studies, however, have shown that individuals who get migraines with an aura (headaches with visual changes) are at greater risk of stroke. Cancer is recognized as a risk for stroke in young adults until age 60. A large Teenage and young cancer survivor study showed a 50% higher-than-expected occurrence of ischemic stroke after a malignancy. This may be related to the toxic effects of chemotherapy and/or radiotherapy rather than cancer itself.
A tear in the arteries of the neck is the cause of stroke in about 20% of young adults. This can be caused by high blood pressure, migraine, trauma in the neck area, or systemic infections. Stroke that occurs with no clear risk factors (cryptogenic stroke) is strongly associated with a congenital hole between the upper chambers of the heart (atrial septal defects such as a patent foramen ovale). These accounts for approximately 1/3 of all stroke in the young. The theory is that this kind of congenital defect makes it easier for blood clots to pass between the chambers and cause a stroke. Treatment may include surgical closure of the cardiac defect.
In light of the long-term effects of stroke on quality of life, it is imperative that modifiable risk factors such as lifestyle change be addressed as early as possible.
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