Elderly patients with moderate sleep apnea live longer than their counterparts, says study

Mar 24 2010

Findings from the Technion-Israel Institute of Technology could provide good news for elderly patients who suffer from sleep apnea. The research results from Prof. Peretz Lavie and Dr. Lena Lavie of the Faculty of Medicine show that elderly patients with moderate sleep apnea live longer than their counterparts in the general population.

In an article published in the December 2009 issue of the Journal of Sleep Research, the researchers hypothesize that the intermittent lack of oxygen (hypoxia) that occurs with sleep apnea actually provides protection to elderly patients' cardiovascular systems. This would explain, they say, why elderly patients with moderate sleep apnea show significantly lower mortality rate compared with the general population. The findings were based on a study of 611 individuals with a media age of 70, and a five-year follow-up period.

Behind this phenomenon, say the researchers, is a protein in the blood known as VEGF (vascular endothelial growth factor), which is created during hypoxia, and which is responsible for the growth of new blood vessels. The study found that the ability of individuals to produce VEGF varied widely among patients, and individuals who could produce a large amount when exposed to hypoxia had more blood vessels around their hearts when compared to individuals who could not. The resulting reservoir of blood, they believe, provides protection in the case of heart attack.

Researchers at Heinrich Heine University in Dusseldorf, Germany recently confirmed the Lavies' hypothesis. In the most recent issue of Chest, the Journal of the American College of Chest Physicians, Stephan Steiner and colleagues from the Department of Cardiology reported that patients with sleep apnea had significantly more blood vessels around their hearts than patients without sleep apnea - even though there were no differences between the groups in age, weight, heart condition or use of medication.

"If confirmed, these findings may have important clinical implications regarding treatment of sleep apnea syndrome," say Prof. and Dr. Lavie in an editorial that accompanied the Chest article. "Moreover, such findings, if combined with individual gene analysis, may provide new treatment strategies for cardiovascular protection."

Sleep apnea is characterized by interruptions in breathing during sleep that last 10 seconds or more, at least five times per hour. They cause repeated interruptions of sleep and decreased oxygen levels in the blood, and have been linked with cardiovascular diseases, especially hypertension. The condition affects up to 10 percent of adult men, who in most cases are not aware that their breathing stops during sleep but who complain of chronic fatigue, excessive sleepiness, tendency to doze off during the day and loud, intermittent snoring.

Source: Technion-Israel Institute of Technology .