Otherwise healthy middle-aged people with Obstructive sleep apnea - a disorder in which they frequently stop breathing for brief periods while they sleep - show early signs of hardening of their arteries, according to a report from Brazil.

“Our findings support the hypothesis of a direct link between obstructive sleep apnea and cardiovascular diseases,” said Dr. Luciano F. Drager.

Drager and his team at the University of Sao Paolo measured indicators of early atherosclerosis in 30 patients with untreated Obstructive sleep apnea and in 12 matched healthy volunteers. None of the participants had previous evidence of cardiovascular disease.

The measurements of early atherosclerosis tended to show a direct correlation with the severity of sleep apnea, the investigators report in the American Journal of Respiratory and Critical Care Medicine.

A parameter reflecting artery stiffness was significantly higher among patients with severe sleep apnea than among patients with milder apnea and among the healthy comparison group, the report indicates. The same was found for the thickness of the artery walls.

“The novel finding in the present study is that middle-aged patients with severe Obstructive sleep apnea, without overt cardiovascular diseases, demonstrate early signs of atherosclerosis,” the researchers conclude.

“We are currently performing a randomized study with CPAP (continuous positive airway pressure) to evaluate the impact on these signs of atherosclerosis,” Drager said.

CPAP delivers pressurized air via a facemask to patients while they sleep, to prevent their airways becoming blocked. It is usually used to relieve the sleep interruptions that lead to dangerous sleepiness during the day.

“This study should add important evidences to justify the (greater) use of CPAP in patients with Obstructive sleep apnea, even in the absence of prominent sleepiness-related daytime symptoms,” Drager noted.

SOURCE: American Journal of Respiratory and Critical Care Medicine, September 1, 2005.