According to the American Heart Association, "stroke is the leading cause of serious, long-term disability in the United States". The group’s
The Stroke Association defines a stroke as a "brain attack which occurs when a blood clot blocks an artery (a blood vessel that carries blood from the heart to the body) or a blood vessel (a tube through which the blood moves through the body) breaks, interrupting blood flow to an area of the brain."
There are two types of stroke. Ischemic stroke occurs when a blood vessel which supplies the brain bocomes blocked. It is the most common, accounting for an estimated 87% of all stroke cases. Hemorragic stroke occurs when blood leaks into the brain from a broken blood vessel and is more often fatal. Without the flow of blood and oxygen, brain cells die, which results in brain damage and disability.
Heart Disease and Stroke Statistics, 2009 Update, also reports that, on average, every 40 seconds, someone has a stroke, and each year, about 795,000 people experience a stroke. There are almost five million stroke survivors in America today.Stroke Causes Different Disabilities
The type and severity of disability caused by stroke depends on what part of the brain was affected and the severity of the damage incurred. According to the National Institute of Neurological Disorders and Stroke, "generally, stroke can cause five types of disabilities: paralysis or problems controlling movement; sensory disturbances including pain; problems using or understanding language; problems with thinking and memory; and emotional disturbances."
Stroke Treatments Today
There are many treatments and therapies for stroke victims. Today, the most widely used are various medications, often combined with physical and/or speech therapy. In addition to medication and physical therapy, there is promising research on the benefits of stem cell treatments for stroke victims. More than 100 studies have been reported by the National Institutes of Health, a division of the U.S. Department of Health and Human Services. Some stem cell treatments would facilitate or improve the recovery and rehabilitation after a stroke. Other stem cell research focuses on the ability to repair damage done during a stroke.
Stem Cell Treatment for Stroke Survivors
One of the latest studies being funded by the National Institutes of Health is based out of the University of Texas at Houston. The study aims to use a patient's own stem cells harvested from bone marrow to repair the brain as quickly as possible after the stroke episode (within 24-72 hours of initial symptoms). If effective, it will help to reduce disability incurred due to brain damage. As of April 2009, at least one patient has undergone this stem cell treatment with encouraging preliminary results.
This clinical study builds on laboratory and animal research which indicated that stem cells can migrate to the injured area of the brain and help repair damage. The prior research showed that, while the stem cells did not generate new brain cells as the scientists had hypothesized, they did cause the cells to protect nerve tissue from damage due to inflammation. When the scientists compared results to the animals that did not receive the injected cells, they found that the animals who received the stem cell therapy showed 60% less nerve tissue damage.
A similar study was conducted at Stanford University in California in 2008, where animals' brains were injected with neural tissue derived from human embryonic stem cells. In this study, the animals demonstrated improved mobility and strength in the parts of their bodies affected by the stroke.
There currently are several research studies underway which investigate the benefits of human umbilical cord stem cells as a treatment for stroke recovery. One study, announced in January 2009, is investigating the benefit of using umbilical cord stem cells in combination with mannitol, a prescription medication with diuretic properties which currently is used to help brain trauma victims.
Both public and privately-funded research programs investigating the use of various types of stem cells to aid stroke victims continue to make rapid and promising progress.