Selected routine laboratory tests in the clinical assessment of patients with obstructive sleep apnea.

INTRODUCTION: Obstructive sleep apnea (OSA) is a chronic disease characterized by repetitive complete or partial occlusion of the upper airways during sleep with respiratory muscle effort, which leads to consecutive apneas and hypopneas. Obstruction of the upper airways during sleep leads to repetitive episodes of disrupted airflow and consequent changes in blood oxygenation, resulting in hypoxaemia and hypercapnia. Intermittent hypoxaemia induces the production of pro-inflammatory factors and promotes metabolic dysregulation and platelet aggregation. OBJECTIVE: The main aim of this study was to determine differences, if any, in selected standard parameters in routine laboratory tests often used in GP practice between patients with obstructive sleep apnea, without comorbidities, and a well-defined control group with the absence of this syndrome proven in polygraphic examination. MATERIAL AND METHODS: Of the 192 clinically assessed persons with suspected OSA and admitted to the Internal Medicine Department in Lublin, 85 were qualified for the study after application of exclusion criteria. Demographic and health behaviour-related data, medical history regarding sleep habits and cardiovascular disease, were collected from each patient. RESULTS: Apart from significantly higher MCV and MCH among the cpontrol group, no significant differences were found between patients with obstructive sleep apnea and the control group. CONCLUSIONS: The results can be useful for the holistic assessment of the health status of patients with newly-diagnosed OSA.

Level of Serum Fetuin-A Correlates with Heart Rate in Obstructive Sleep Apnea Patients without Metabolic and Cardiovascular Comorbidities.

Obstructive sleep apnea (OSA) is the most common type of sleep-induced breathing disorder in the adult population and significantly affects the condition of the cardiovascular system. Fetuin-A (Fet-A) is a hepato- and adipokine, which prevents vessel calcification, and its level correlates with atherogenesis and metabolic disorders. The associations of cardiovascular diseases (CVD) both with OSA, which increases CVD risk, and Fet-A, which prevents CVD, justify the question of their mutual interactions in patients with OSA. Therefore, we sought to analyze Fet-A as an early biomarker of CVD risk in OSA patients without metabolic and cardiovascular comorbidities except for properly controlled arterial hypertension. We have found that in these patients, OSA does not appear to directly affect Fet-A levels. However, high Fet-A levels were more common in the group of patients with OSA, and the hypopnea index was significantly higher among subjects with the highest Fet-A levels. The level of Fet-A in OSA patients positively correlates with pulse rate, and it does not correlate with pulse pressure in this group unlike in the control group, where such a relationship exists. To our best knowledge, this is the first study to analyze this relationship in OSA patients without any significant cardiovascular comorbidities.