Obstructive sleep apnea syndrome in the continuum of uncontrolled hypertension

Aim. To assess frequency and severity of sleep breathing disorders in patients with uncontrolled hypertension among patients referred to a sleep laboratory. Materials and methods. 113 patients aged 18-80 years with arterial hypertension (AH) were included. All patients underwent sleep cardiorespiratory monitoring, general clinical and laboratory diagnostics. Uncontrolled hypertension was defined as systolic blood pressure (BP) >140 mm Hg, or diastolic BP >90 mm Hg. in case of permanent antihypertensive therapy (AHT) taking. Results. Among all patients with uncontrolled hypertension (Group 1; n=42, 37,2%), 95,2% had obstructive sleep apnea syndrome (OSA). Compared with the controlled hypertension group (Group 2), AHI and ODI were higher in Group 1 (AHI 28,0 events/hour [14,8; 51,8] vs. 17,5 events/hour [8,7; 39,0], p=0,03; ODI 25,3 events/hour [14,4; 50,6] versus 17,1 events/hour [8,5; 37,0], p=0,04). In addition, these parameters turned out to be markers of uncontrolled hypertension (AHI >19,9 events/hour, AUC=0,62, p=0,03; OR 3,23, 95%; CI 1,7-6,1, p=0,00; ODI >19,5 events/hour, AUC=0,62, p=0,03; OR 3,07, 95% CI 1,7-5,7, p=0,01). The level of systolic BP >146 mm Hg. turned out to be a marker of the moderate or severe OSA (AUC=0,66, p=0,00; OR 4,45, 95% CI 1,811,2, p=0,00). Conclusion. High incidence of moderate or severe OSA in patients with uncontrolled hypertension emphasizes the importance of sleep breathing disorders examining in these patients. Timely diagnostics and treatment of OSA probably will allow to provide better BP levels control and thus will lead to reducing of cardiovascular risk.