Stroke is the third leading cause of death in the United States, after heart disease and cancer.
While some stroke can be deadly, most of the strokes can probably be treated if victims act quickly. Clot-busting drugs are used to prevent permanent disability after a stroke. However, victims must receive the treatment within a 4-and-a-half-hour window after the stroke symptoms begin.
When a person has a stroke during sleep, he or she could not possibly know when stroke occurred. As such, they could not receive the treatment if he or she slept for more than 4 and a half hours.
A study conducted by researchers from the University of Cincinnati reported nearly 15 percent of people who had a stroke while they slept making them not eligible for clot-busting treatment. Their findings were published online on May 9, 2011 in the journal ‘Neurology’.
The researchers reviewed medical records from people who went to emergency rooms in Ohio and Kentucky in 2005 in order to investigate how many strokes occur during sleep, and whether they differ from strokes that begin while people are awake.
Among the identified 1,854 people who had suffered the most common kind of stroke, in which blood flow to the brain becomes blocked, 273 (almost 15 percent) said they woke up with symptoms.
There were no major differences between strokes that occurred while people were asleep and awake. But people who had wake-up strokes were slightly older and their strokes were somewhat more severe.
None of the patients who woke up with symptoms got the clot-busting drug known as tPA (tissue Plasminogen Activator). In fact, one third of these victims could have received the drugs if time had not been an issue. They also did not have any other reasons like high blood pressure or a recent surgery that would disqualify them from receiving tPA.
According to the researchers, doctors are reluctant to give iPA to stroke patients after the crucial time window because the treatment comes with a risk of bleeding in the brain. Meanwhile, research had not shown any benefits if it is given long after symptoms began.
Perhaps, scientists should find out how to estimate when wake-up strokes actually occurred so that doctors could determine those who wake up with stroke symptoms to receive iPA.