Expired CME Article
Inflammatory Aspects of Sleep Apnea and Their Cardiovascular Consequences
Abstract
Obstructive sleep apnea (OSA) is a common medicalcondition that occurs in a considerable percentage of the population.
Substantial evidence shows that patients with OSA have an increased
incidence of hypertension compared with individuals without OSA,
and that OSA is a risk factor for the development of hypertension.
It is established that OSA may be implicated in stroke and transient
ischemic attacks. OSA is associated with coronary heart disease,
heart failure, and cardiac arrhythmias. Pulmonary hypertension may
be associated with OSA, especially in patients with pre-existing
pulmonary disease. Although the exact cause that links OSA with
cardiovascular disease is unknown, there is evidence that OSA is
associated with a group of proinflammatory and prothrombotic factors
that have been identified as important in the development of
atherosclerosis. OSA is associated with increased daytime and nocturnal
sympathetic activity. Autonomic abnormalities seen in patients
with OSA include increased resting heart rate, decreased R-R
interval variability, and increased blood pressure variability. Both
atherosclerosis and OSA are associated with endothelial dysfunction,
increased C-reactive protein, interleukin 6, fibrinogen, plasminogen
activator inhibitor, and reduced fibrinolytic activity. OSA
has been associated with enhanced platelet activity and aggregation.
Leukocyte adhesion and accumulation on endothelial cells are common
in both OSA and atherosclerosis. Clinicians should be aware
that OSA may be a risk factor for the development of cardiovascular
disease.
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