Assessment of the relationship between endocan and obstructive sleep apnea severity

Obstructive sleep apnea (OSA) and endothelial dysfunction are associated with cardiovascular risk factors and the development of atherosclerosis. Endocan is a marker of endothelial dysfunction, while obstructive sleep apnea is one of the causes of endothelial dysfunction. In this study, we investigated the relationship between endocan and obstructive sleep apnea severity.

A total of 179 patients with snoring complaints were included. All patients underwent polysomnography, and based on the results, the participations were allocated to the control group (n = 39) or to the obstructive sleep apnea group (n = 140). The OSA group was classified as having mild (apnea-hypopnea index (AHI) = 5-15; n = 43), moderate (AHI = 15-30; n = 42), or severe OSA (AHI > 30; n = 55). All participations had their endocan levels measured.

Endocan levels in OSA patients were significantly higher than in the control group (11.8 (3.13-200) vs 3.13 (3.13-23) ng/ml, p < 0.001). Also, endocan levels were significantly higher in the severe OSA group than moderate and mild obstructive OSA (13.2 (3.13-200), 12.6 (3.13-200) and 8.44 (3.13-50.5) ng/ml, p = 0.015, respectively). Multiple logistic regression analysis showed that smoking, age and endocan levels were independent predictors of OSA severity (p = 0.024, p = 0.037, p = 0.004, respectively).

Endocan seems to be a potential risk stratification marker in this patient population.