Obstructive Sleep Apnea Could Be Fatal For Stroke Patients!
Posted Mar 12 2010 8:29am
Sleep apnea is a condition in which a person’s breathing can briefly cease or become blocked numerous times during the night. Sleep apnea occurs frequently among patients with stroke, but whether it is an independent risk factor for mortality is still unknown.
In order to understand this relationship better, researchers from Umea University Hospital in Sweden examined long-term survival among 132 stroke patients admitted for in-hospital stroke rehabilitation between 1995 and 1997. All the participated patients underwent overnight sleep apnea recording about 3 weeks after their stroke, and they were followed for an average of 10 years.
Out of the 132 participants, 23 patients (17.4 percent) had obstructive sleep apnea and 28 patients (21.2 percent) had central sleep apnea during Cheyne-Stokes respiration. 2 patients who had both obstructive and central sleep apnea were excluded. A total of 79 patients served as controls.
Researchers found that 116 (88 percent) patients had died at follow-up. This included all patients with obstructive sleep apnea, 96 percent of those with central sleep apnea and 81 percent of patients without either form of sleep apnea. Obstructive sleep apnea is a condition in which breathing is blocked by collapsing airway tissues while central sleep apnea is one in which respiration controlled by the brain is interrupted.
The results showed that central sleep apnea was not associated with increased mortality. However, the mortality rates of patients with obstructive sleep apnea were 76 percent higher than those without apnea.
In the paper published on February 11, 2008 in the Archives of Internal Medicine, the researchers pointed out that it could be the drop in nighttime levels or oxygen in the bloodstream and an increased risk of cardiac arrest that might account for the increased mortality among stroke patients who have sleep apnea.