[Sleep apnea as a risk marker in coronary heart disease]

Obstructive sleep apnea (OSA) and coronary heart disease (CHD) are both frequent in the middle ages. Both disease share a similar spectrum or risk factors and attendant diseases. The aim of the study was to determine the prevalence of obstructive sleep apnea in patients with coronary heart disease diagnosed by coronary angiography. Furthermore, influence of sleep apnea and attendant diseases and risk factors for coronary heart disease, especially the risk for myocardial infarction and reduced left ventricular ejection fraction, was investigated. We included in this study 143 patients (121 men, 22 women mean age 60 +/- 8 years (35-81) who underwent coronary angiography because of angina pectoris or were suspicious for CHD due to noninvasive investigations. These patients has symptoms of OSA based on a standardized questionnaire. They underwent a four-channel screening with a non-laboratory-monitoring-system (NLMS) for detection of sleep-related breathing disorders. In addition, spectrum of risk factors and concomitant diseases were considered. Sleep apnea was more frequent in patients with CHD (30.6%) in comparison to patients without CHD (21.8%), but did not reach statistical significance. Patients with CHD and OSA had a significantly higher frequency of a history of myocardial infarction and had a significantly lower left ventricular ejection fraction than patients without OSA.

Patients with the combination of OSA and CHD are at higher risk for myocardial infarction and reduced left ventricular ejection fraction. Patients with CHD should be screened for OSA in case of secondary prevention.