Carotid intima-media thickness is not associated with homocysteine and vitamin D levels in obstructive sleep apnea

Obstructive sleep apnea syndrome (OSA) is associated with increased vascular morbidity. Accelerated atherosclerosis might be one of the most important mechanisms linking OSA with the development of vascular disorders. Homocysteine (HCY) and vitamin D has been associated with atherogenesis. The aim of this study was to assess a possible association between the levels of HCY and vitamin D and the carotid intima-media thickness (cIMT), which is a known marker for subclinical atherosclerosis in patients with OSA. We prospectively enrolled 110 patients with the history of snoring, who underwent standard overnight polysomnography. Clinical characteristics of the population were recorded on admission and blood samples were obtained in the fasting condition following morning. Extracranial cIMT measurements were performed according to the standardized scanning protocol. A significant correlation was found between cIMT and apnea-hypopnea index (r = .276, p = .006), age (r = .486, p < .001), diabetes mellitus (r = .377, p < .001), coronary artery disease (r = .274, p = .006) and history of stroke (r = .251, p = .012). We failed to find any significant correlation between cIMT and the levels of HCY (r = .036, p = .724) or vitamin D (r = .027, p = .800). In conclusion, our data suggest that the association of cIMT with the severity of OSA can be influenced by multiple metabolic consequences of OSA including traditional and non-traditional risk factors. HCY and vitamin D do not seem to play a superior role in this process.