Objective:
Some studies have shown the atherogenic dyslipidemia as being sometimes independent of the obesity; however, with a close relation to the obstructive sleep apnea (OSA). The aim of this study was to investigate a relationship between parameters defining the quality of sleep and the standard lipid profile despite the obesity.

Methods:
The data of 211 patients with suspected OSA were analyzed prospectively. The following tests were performed: polysomnography, morphometric assessment and serum lipid levels.

Results:
Value of AHI showed a positive correlation with TG, TG/HDL ratio, BMI, plasma atherogenic index (API), circumference of neck, waist, and hip, and WHR. A negative correlation was found between AHI and HDL. The patients with severe OSA (AHI>30) differ significantly from the patients with moderate and mild OSA in terms of TG, and the ratio of TG /HDL and API and they are, therefore, in the group of much higher risk of cardiovascular disease. Significant predictors of the severity of sleep apnea are as follow: the ratio of TG/HDL, BMI and the neck circumference. The arousal index was the only parameter of the sleep quality significantly associated with the level of TG.

Conclusion:
The most important parameters of the quality of sleep that determine atherogenic risk are AHI and arousal index that are significantly correlated with TG/HDL ratio. Particularly, high risk of cardiologic problems applies to patients with AHI>30 who substantially differ in terms of lipid profile from the patients with mild or moderate OSA. Arousal index significantly distinguishes patients with AHI> 30 from the other groups of patients.