Abstract
Background: Obstructive sleep apnea (OSA) occurs mainly in middle aged subjects and is associated with a higher incidence of cardiovascular complications.
Aim: Assessment of subclinical cardiovascular risk factors in asymptomatic younger OSA patients.
Methods: Patients undergoing a full polysomnography and with an apnea hypopnea index (AHI) >20, were included. They underwent an echocardiography, a measurement of the carotid intima media thickness (IMT), analysis of the endothelial function (brachial flow mediated dilatation, FMD) and a Multislice Computed Tomography (CT) for determination of the coronary plaque burden. We assessed 13 coronary segments for degree of stenosis (1: normal; 2: <50% stenosis; 3: 50-70% stenosis; 4: >70% stenosis).
Results: The patients [n=91; age=50±10y, M/F 79/12] had severe OSA, mean AHI of 52±23, and 59% had up to eleven coronary segments showing a variable degree of plaque burden. There was a significant correlation between the number of affected coronary segments and IMT (r=0.451; p<0.001), FMD (r=-0.255; p=0.019), coronary arterial calcium score (r=0.546;p<0.001), interventricular septum thickness (r=0.217;p=0.041) and age (r=0.414;p<0.01). Correlations were maintained after adjustment for hypertension, age and smoking. Patients with coronary plaques were older (54±9y versus 47±9y; p<0.01), had thicker IMT (680±127μm versus 587±89μm; p<0.01) and had abnormal FMD (6.1±2.1% versus 7.3±2.5%; p=0.029).
Discussion: Our results suggest occurrence of significant subclinical coronary abnormalities and endothelial dysfunction in asymptomatic younger severe OSA patients. Routine screening for subclinical cardiovascular risk factors in OSA may be beneficial.
- © 2011 ERS