Comparison of forearm endothelial function between premenopausal and postmenopausal women with or without hypercholesterolemia.
ABSTRACT We sought to determine whether menopausal status or postmenopausal hypercholesterolemia affects forearm resistance artery endothelial function. We studied the forearm resistance artery endothelial function in 75 Japanese women: 25 premenopausal volunteers, 25 postmenopausal women with normal serum low-density lipoprotein (LDL) cholesterol concentrations, and 25 hypercholesterolemic postmenopausal women. Excluded from the study were patients with hypertriglyceridemia, hypertension, or diabetes, cigarette smokers. The forearm blood flow (FBF) during reactive hyperemia and after sublingual nitroglycerin (NTG) administration was measured by strain-gauge plethysmography. The serum concentrations of lipoprotein (a) [Lp(a)] were significantly higher in the hypercholesterolemic postmenopausal group than in the other two groups (P<0.01). These lipid parameters were similar between the premenopausal and postmenopausal women with normal cholesterol. The FBF responses to reactive hyperemia were significantly lower in the postmenopausal hypercholesterolemic women than in the other two groups (P<0.01). The reactive hyperemia also was impaired in the postmenopausal group with normal cholesterol as compared with the premenopausal group (P<0.01). Increases in FBF after NTG were similar between the three groups. By stepwise multivariate analysis, menopausal status and serum LDL cholesterol was the significant predictor of forearm endothelial function. These findings suggest that reactive hyperemia is impaired in forearm resistance arteries after menopause, especially in postmenopausal women with hypercholesterolemia.
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ABSTRACT: To determine the effect of ovarian hormone deficiency on peripheral vascular function. Randomized, single-blind, placebo-controlled. General clinical research center. Twelve healthy, lean, premenopausal women with regular menstrual cycles. Measurements were made during the early to midfollicular and midluteal phases of the menstrual cycle. Patients were then randomized to an 8-week course of gonadotropin-releasing hormone agonist (GnRHa) (n = 6) or placebo (n = 6) and retested. On each occasion, blood flow was assessed in the basal postabsorptive state and under euglycemic-hyperinsulinemic-hyperaminoacidemic conditions. Calf blood flow by venous occlusion plethysmography. No differences in calf blood flow under postabsorptive (1.65 +/- 0.09 vs. 1.73 +/- 0.16 mL/100 g tissue per minute) or insulin-stimulated conditions (2.24 +/- 0.20 vs. 2.30 +/- 0.18 mL/100 g tissue per minute) were found between the follicular and luteal phases of the menstrual cycle, respectively; therefore, pretreatment data were averaged. Ovarian hormone suppression did not alter postabsorptive calf blood flow (GnRHa: 1.68 +/- 0.13 to 1.69 +/- 0.15; placebo: 1.69 +/- 0.21 to 1.64 +/- 0.14 mL/100 g tissue per minute) or the blood flow response to insulin infusion (GnRHa: 2.40 +/- 0.21 to 2.37 +/- 0.29; placebo: 2.10 +/- 0.28 to 2.19 +/- 0.35 mL/100 g tissue per minute). Variation in ovarian hormones associated with the menstrual cycle or short-term ovarian hormone deficiency induced by GnRHa do not affect calf blood flow under postabsorptive conditions or the response to hyperinsulinemia.Fertility and sterility 09/2006; 86(2):440-7. · 3.97 Impact Factor
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ABSTRACT: Endothelial dysfunction characterizes many disease states including subclinical atherosclerosis. The consumption of flavanol-rich cocoa and cocoa-based products has been shown to improve endothelial function in both compromised and otherwise normal, healthy individuals when administered either acutely or over a period of several days, or weeks. Women experience increased risk for cardiovascular disease after menopause, which can be associated with endothelial dysfunction. Whether a flavanol-rich cocoa-based product can improve endothelial function in hypercholesterolemic postmenopausal women is not known. The purpose of the present study was to determine whether chronic dietary administration of flavanol-rich cocoa improves endothelial function and markers of cardiovascular health in hypercholesterolemic postmenopausal women. Thirty-two postmenopausal hypercholesterolemic women were randomly assigned to consume a high-flavanol cocoa beverage (high cocoa flavanols (CF)--446 mg of total flavanols), or a low-flavanol cocoa beverage (low CF--43 mg of total flavanols) for 6 weeks in a double-blind study (n=16 per group). Endothelial function was determined by brachial artery-reactive hyperemia. Plasma was analyzed for lipids (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol), hormones (follicle-stimulating hormone), total nitrate/nitrite, activation of cellular adhesion markers (vascular cell adhesion molecule 1, intercellular adhesion molecule 1, E-Selectin, P-Selectin), and platelet function and reactivity. Changes in these plasma markers were then correlated to brachial reactivity. Brachial artery hyperemic blood flow increased significantly by 76% (P<0.05 vs. baseline) after the 6-week cocoa intervention in the high CF group, compared with 32% in the low CF cocoa group (P=ns vs. baseline). The 2.4-fold increase in hyperemic blood flow with high CF cocoa closely correlated (r2=0.8) with a significant decrease (11%) in plasma levels of soluble vascular cell adhesion molecule-1. Similar responses were not observed after chronic use of low CF. There were no significant differences between high and low CF in other biochemical markers and parameters measured. This study is the first to identify beneficial vascular effects of flavanol-rich cocoa consumption in hypercholesterolemic postmenopausal women. In addition, our results suggest that reductions in plasma soluble vascular cell adhesion molecule-1 after chronic consumption of a flavanol-rich cocoa may be mechanistically linked to improved vascular reactivity.Journal of Cardiovascular Pharmacology 02/2006; 47 Suppl 2:S177-86; discussion S206-9. · 2.38 Impact Factor
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ABSTRACT: Menopause is considered to be a cardiovascular risk factor, but this belief is based on opinions rather than on evidence. Confounding effects of age are often neglected. Population-based study with further subanalysis of case-to-case age-matched cohorts of men and fertile and menopausal women. Epidemiology in primary, public, institutional frame. Nine thousand three hundred and sixty-four men and women aged 18-70 years representative of Italian general population followed-up for 18.8 +/- 7.7 years. Blood pressure (BP), prevalence and incidence of hypertension, serum total, high-density lipoprotein and low-density lipoprotein cholesterol, glucose tolerance, body adiposity, vascular reactivity, target organ damage, overall and cardiovascular mortality and morbidity, by gender and by menopausal status. Cross-sectional: crude BP, pressor response to cold, orthostatic BP decrease, BMI, skinfold thickness, fasting and postload blood glucose and insulin, serum lipids, left ventricular mass, serum creatinine, microalbuminuria and augmetantion index were higher in menopausal than in fertile women, and comparable in menopausal women and men, a difference that was no longer present when adjusting for age or considering age-matched cohorts. Longitudinal: BP increase during follow-up, cardiovascular mortality and morbidity were greater in menopausal than in fertile women, and comparable in menopausal women and men, a difference no longer present in age-matched cohorts. Menopausal status was rejected from multivariate Cox analysis also including age. The cardiovascular effects usually attributed to menopause seem to be a mere consequence of the older age of menopausal women.Journal of Hypertension 11/2008; 26(10):1983-92. · 3.81 Impact Factor