SESSION TYPE: Sleep Posters
PRESENTED ON: Wednesday, October 24, 2012, 2012 at 01:30 PM - 02:30 PM
PURPOSE: The purpose of our study was to describe the spectrum of brachial artery reactivity, and assess an important marker of endothelial inflammation (Nitric Oxide) - in a group of hypertensive population with and without OSAHS, non hypertensive patients with OSAHS, and in Obese patients without OSAHS compared to healthy volunteers.
METHODS: One hundred and fifty subjects were enrolled and subdivided into: (Group I) Forty patients with controlled essential systemic hypertension., (Group II) Forty patients with resistant hypertension. All hypertensive patients (groups I and II) were subjected to limited cardio respiratory sleep study, and subdivided based on the presence or absence of obstructive sleep apnea hypopnea syndrome.(Group III) Thirty non hypertensive patients newly diagnosed to have OSAHS.(Group IV) Thirty non hypertensive obese otherwise apparently healthy. (GroupV, Control group) Ten non-smoking healthy volunteers. Assessment of vascular reactivity was done using Doppler ultrasound assessment of brachial artery responsiveness to both endothelium -dependent and endothelium -independent stimuli, then measurement of marker of endothelial inflammation was done including level of plasma Nitric oxide . Representative samples were taken to undergo assessment of plasma level of nitric oxide .
RESULTS: Brachial artery reactivity showed a significantly blunted response to shear stress (Endothelium Dependent stimulus) in patients with OSAHS, in patients with resistant hypertension and in patients with both OSAHS and hypertension. On the other hand, NTG mediated dilation (Endothelium Independent stimulus) was also significantly blunted in patients with resistant hypertension with or without OSAHS and in patients with severe OSAHS. Serum Nitrates was found to be of statistically significantly lowest values in patients with severe OSAHS, and in patients with both OSAHS and hypertension. Obesity alone, as well as hypertension alone were also associated with decreased levels of serum Nitrates but to a much lesser extent than OSAHS combined to hypertension.
CONCLUSIONS: Endothelial dysfunction is considered a pre-hypertension step in patients without overt hypertension. It is considered a marker of systemic inflammation which can be detected in patients with OSAHS
CLINICAL IMPLICATIONS: Measures to restore endothelial integrity are of utmost importance in clinical practice to guard against the development of hypertension, CAD, CVS, and other clinical syndromes
DISCLOSURE: The following authors have nothing to disclose: Heba Gharraf, Mohamed Samy Atta, Mahmoud Ibrahim, Mohamed Mabrouk Elhoffy, Iman ElSharkawy
No Product/Research Disclosure InformationFaculty of Medicine, Alexandria University, Egypt, Alexandria, Egypt