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Untreated obstructive sleep apnea (OSA) is common in patients with hypertension and may impair blood pressure (BP) and target-organ damage responses to antihypertensive therapy. In this study, we recruited hypertensive patients who underwent treatment with a 30-day regimen of hydrochlorothiazide 25 mg plus enalapril (20 mg BID) or losartan (50 mg BID) and were assessed with a baseline clinical evaluation, polysomnography, 24-hour ambulatory BP monitoring, and carotid-femoral pulse wave velocity. All the examinations except for polysomnography were repeated at 6 and 18 months of follow-up. We studied 94 hypertensive patients (mean age, 55±9 years). The frequency of OSA was 55%. Compared with baseline, we did not observe significant differences between groups in 24-hour BP, daytime systolic and diastolic BPs, or night-time systolic BP at 6 and 18 months. The BP control rate at 24 hours (P =0.027). There were no differences in the number and class of antihypertensive medications prescribed during follow-up. In terms of arterial stiffness, patients with OSA had higher pulse wave velocity than did patients without OSA at baseline (10.3±1.9 versus 9.2±1.7 m/s; P =0.024), but both groups had similar decreases in pulse wave velocity during follow-up. In conclusion, with combined antihypertensive treatment aimed at controlling BP, hypertensive patients with OSA had similar 24-hour BP and arterial stiffness to those without OSA.

Whether sex influences the association of obstructive sleep apnea (OSA) with markers of cardiovascular risk in patients with hypertension is unknown. In this study, 95 hypertensive participants underwent carotid-femoral pulse wave velocity, 24-hour ambulatory blood pressure monitoring, echocardiogram, and polysomnography after a 30-day standardized treatment with hydrochlorothiazide plus enalapril or losartan. OSA was present in 52 patients. Compared with non-OSA patients, pulse wave velocity values were higher in the OSA group (men: 11.1±2.2 vs 12.7±2.4 m/s, P=.04; women: 11.8±2.4 vs 13.2±2.2 m/s, P=.03). The proportion of diastolic dysfunction was significant in men and women with OSA. Compared with non-OSA patients, nondipping systolic blood pressure in OSA was higher in men (14.3% vs 46.4%) and in women (41.4% vs 65.2%). OSA was independently associated with pulse wave velocity (β=1.050; P=.025) and nondipping systolic blood pressure (odds ratio, 3.03; 95% confidence interval, 1.08-8.55; P=.035) in the regression analysis. In conclusion, OSA is independently associated with arterial stiffness and nondipping blood pressure in patients with hypertension regardless of sex.

Introduction: In men with hypertension, obstructive sleep apnea (OSA) is associated with increased arterial stiffness. However, it is not clear if the impact of OSA on patients with hypertension is similar in women. Methods: We recruited consecutive patients with established diagnosis of hypertension under a standardized antihypertensive treatment (hydrochlorothiazide plus enalapril or losartan). All patients were submitted to full polysomnography and carotid-femoral pulse wave velocity (PWV). We performed analysis according to the presence of OSA (defined by an apnea-hypopnea index ≥15 events/hour of sleep) and by gender (male and females). Results: Ninety-five patients were studied (14males without OSA; 28 males with OSA, 29 females without OSA and 24 females with OSA). OSA frequency was 66% in males group versus 45% in females group (p=0.02). The age of female with OSA (59±10yrs) was significantly higher than female without OSA(52±10yrs), while the age did not differ between the male with(58±10yrs) or without OSA(56±8yrs). The BMI was also significantly greater in female with OSA (32.8±5 vs. 28.7±5kg/m2), while was similar in male with(30.5±4.5) or without OSA(29.5±2.5). The blood pressure was not different in the patients with or without OSA. PWV was significantly higher in both male(12.7m/s) and female(13.2m/s) with OSA than the couterparts without OSA(male-11 m/s, female-11.7 m/s) even after adjustments by age. The multivariate linear regression showed that OSA was independently associated with PWV(p=0.008). Conclusions: In patients with hypertension, the presence of OSA is associated with higher PWV regardless of gender.

Objective— During hypoxia, active substances released by the endothelium play a key role in the cardiovascular and respiratory responses elicited to optimize oxygen delivery. As hypercholesterolemia is a major cause of endothelial dysfunction, it may interfere with these responses. Methods and Results— We studied cardiovascular and ventilatory responses to acute systemic hypoxia in 14 patients with hypercholesterolemia (HC) and 13 control (CO) subjects. Oxygen saturation decreased similarly in both groups. Diastolic blood pressure increased only in the HC group ( P =0.0002) and, despite systolic blood pressure increases both in the HC group, 140±4 (95% confidence interval [CI],131 to 149 mm Hg) to 154±4 mm Hg (95% CI,145 to 164 mm Hg), and in the CO group, 133±3 (95% CI,126 to 140 mm Hg) to 140±4 mm Hg (95% CI,132 to 148 mm Hg), the HC group showed an enhanced pressor response ( P =0.03, group comparison). Both groups had increased forearm blood flow, but the decrease in forearm vascular resistance in the CO group, 40±5 (95% CI, 30 to 51 UR) to 31±4 UR (95% CI,23 to 39 UR) ( P =0.0001) was not seen in the HC group, 29±3 (95% CI, 22 to 37 UR) to 26±3 UR (95% CI, 20 to 33 UR), ( P =0.03, group comparison). Conclusions— Hypercholesterolemic patients demonstrate a hyperreactive pressor response and absence of forearm vasodilation during acute systemic hypoxia.