Independent association between obstructive sleep apnea and noncalcified coronary plaque demonstrated by noninvasive coronary computed tomography angiography.

BACKGROUND

Coronary artery atherosclerosis has been associated with obstructive sleep apnea (OSA). However, the type and severity of plaque formation have not been characterized. This study evaluated the association of coronary noncalcified plaques and severity of stenosis in patients with OSA.

METHODS

This study was a retrospective analysis of 81 patients, 49 with OSA and 32 without OSA, who had undergone multidetector-row helical computed tomography scanning. The board-certified radiologist was blinded to the diagnosis of OSA and reviewed the scans for plaque characterization, severity of stenosis, and number of vessels involved.

RESULTS

Of the 81 patients reviewed, the mean apnea-hypopnea index in the OSA group was 42.2 vs 7.5 in the non-OSA group. The groups did not significantly differ in the distribution of comorbid conditions. We found that among the patients with OSA, 63% had noncalcified/mixed plaques, as opposed to 16% in the non-OSA group (P < 0.0001), with unadjusted odds ratio of 9.3 (3.0, 28.4). After adjustment for other risk factors such as age, sex, race, hypercholesterolemia, and history of smoking, the association remained strong, with an odds ratio of 7.0 (1.9, 26.5; P < 0.05).

CONCLUSIONS

Our study finds that the frequency of noncalcified/mixed plaques is much higher in patients with OSA than in non-OSA patients. Patients with OSA also have more severe stenosis and a higher number of vessels involved. This study adds to a growing body of data regarding our understanding of the association of OSA and atherosclerosis.