They're called "wake-up strokes" because you go to bed feeling normal, then wake up with stroke symptoms.
Unfortunately, this makes it difficult for doctors to determine exactly when the stroke began -- and clot-dissolving drugs have been considered effective only if given within 4 1/2 hours of when a stroke started.
But preliminary research shows that clot-busting treatments appear to be safe for wake-up strokes if patients can get to the emergency room quickly, according to a new study presented today at the American Stroke Association's annual international conference in New Orleans.
In the study of 326 stroke patients at a London medical center, researchers found that wake-up stroke patients treated with the drugs had similar death rates, risk of bleeding inside the brain, and recovery rates when compared to regular stroke patients treated within the 4 1/2-hour window.
Doctors have been reluctant to give clot-busting drugs without knowing when symptoms began because of the bleeding risk, lead researcher Dulka Manawadu, M.D., of King's College Hospital in London, said in a prepared statement.
However, a significant proportion of patients who wake up with stroke symptoms may have suffered a stroke in the early hours of the morning and may still be within the window of time for using the drugs.
The study underscores how critical it is for people who experience stroke symptoms to get to the emergency room so treatment can be started. It's estimated that about 60,000 Americans a year turn up at emergency rooms having suffered a stroke while they were asleep.
"Because wake-up strokes are common, occurring in up to a quarter of stroke sufferers, more research is needed on how to treat these patients," Manawadu said.
In other stroke news from the annual American Stroke Association's international conference:
Severe, rapid memory loss may be linked to -- and could predict -- a future deadly stroke. Research presented at the conference found that older adults who died from stroke had the most severe and rapid memory loss in the years just prior to their stroke, as compared to those who survived or who never had a stroke. Nearly 12,000 people age 50 and older were examined every two years for signs of memory loss and followed up to 10 years. Study authors say memory loss may help gauge a patient's risk for a future fatal stroke.
Opening blocked neck arteries with a stent or surgery equally effective. A large study comparing two procedures to open blocked neck (carotid) arteries found that both a metal stent or surgery kept the arteries clear. Two years after the procedures, less than seven percent of patients had re-blockage, according to research presented at the annual stroke conference. This is much better than bare metal stents placed in coronary arteries, where re-blockage occurs about 20 percent of the time, said lead researcher Brajesh K. Lal, M.D., of the University of Maryland School of Medicine. About 10 percent of strokes are caused by blockages in the neck arteries, which supply blood to the brain.
Sleep apnea linked to silent strokes and small lesions in the brain. People with severe sleep apnea -- more than five episodes per night -- may have an increased risk of silent strokes and small lesions in the brain, according to a small study presented at the annual stroke conference. "Sleep apnea is widely unrecognized and still neglected," said lead researcher Jessica Kepplinger, M.D. She and her researchers found that 51 of 56 stroke patients, average age 67, had sleep apnea and were more likely to have silent strokes and white matter lesions. They suggest that sleep apnea be recognized as another vascular risk factor, such as high blood pressure.