Role of endogenous androgens on carotid atherosclerosis in non-obese postmenopausal women

BackgroundRecent randomized trials on hormone replacement therapy in postmenopausal women raised many doubts about their role in cardiovascular disease prevention. Therefore the role of other sex hormones needed to be investigated. In particular androgens seem to have a protective role on atherosclerosis. The present study was performed to assess the role of endogenous sex hormones on carotid atherosclerosis in postmenopausal women.Methods and resultsWe consecutively enrolled 101 postmenopausal women aged 45–75 (mean age 57.4) years referred to our University hospital menopausal health-screening clinic. The subjects underwent a medical history, a physical examination and biochemical analysis. Extracranial carotid arteries were assessed by ultrasound. Fifty percent of our sample had carotid plaques. On the multivariate logistic regression analysis age, glycaemia (positively) and testosterone (negatively) (P = 0.02) were significantly correlated to carotid atherosclerosis. In non-obese subjects we found that participants in the third tertile had a significantly lower prevalence of carotid atherosclerosis (P = 0.02) compared to those in the first tertile of testosterone.ConclusionsThese results suggest a possible protective role of endogenous androgens at least on carotid atherosclerosis. Of course these preliminary results should be supported by prospective studies. Also the different role of these hormones on obese and non-obese subjects needs to be clarified.     

Large brachial and common carotid artery diameter in postmenopausal women with carotid atherosclerosis

Background and purposeIt is recognized that arteries can enlarge to compensate atherosclerosis. The role of diameter enlargement of unaffected arteries is not well known. We hypothesized that brachial and common carotid arteries diameters were larger in subjects with carotid atherosclerosis compared to subjects without these lesions.MethodsWe measured diameters in the common carotid and brachial arteries. Intimal medial thickness (IMT) of carotid arteries and carotid atherosclerosis were also evaluated using ultrasound in 83 cases and 83 disease-free control subjects.ResultsCommon carotid and brachial diameter was greater in cases (subjects with carotid atherosclerosis) than controls (subjects without carotid atherosclerosis) after adjustment for confounding variables (P < 0.02). Common carotid diameter was also larger in individuals with greater IMT (P < 0.0001), whereas brachial artery diameter was not. Subjects with more than one carotid plaque had larger arterial diameters than those with one or without plaques.ConclusionsCommon carotid and brachial artery diameters are both larger in cases than controls. This result suggests that vascular remodeling is a systemic process and not only a local response to atherosclerosis. The relationship between diameters and burden of disease could also suggest a link between vascular remodeling and severity of disease. Finally, if confirmed in prospective studies, brachial artery diameter could help to identify subjects at high cardiovascular risk, at least in postmenopausal women.     

Large brachial artery diameter and diabetes in post-menopausal women

Background and aim

Vascular remodelling is one of the possible compensatory mechanisms in response to artery wall injury. It was demonstrated that post-menopausal women with carotid atherosclerosis had a larger brachial artery diameter (BAD) than women without carotid plaques. Therefore, it is possible to hypothesise that artery enlargement could be a marker of early atherosclerosis. To investigate the eventual association between carotid and brachial artery diameter and disease affecting the vascular wall, we performed a case–control study in post-menopausal women with or without type II diabetes mellitus.

Methods and results

We enrolled 28 cases (with diabetes) and 56 controls (without diabetes) matched for age and carotid atherosclerosis presence and severity. On the t-test, women with diabetes showed significantly larger brachial and common carotid artery diameters and, as expected, higher plasma glucose level and homeostasis model assessment (HOMA) than women without diabetes. On the univariate analysis, only plasma glucose level results correlated to BAD in the whole sample. Multivariate analysis confirmed that diabetes was a good predictor of brachial and carotid artery diameter, while age, systolic blood pressure and triglycerides were correlated only to the carotid diameter.

Conclusions

Our data confirm that vascular remodelling is a systemic process occurring in conditions related to atherosclerosis, such as type II diabetes. Indeed, artery diameter could be a marker of early response of vessel wall to injury.     

Erectile dysfunction can improve the effectiveness of the current guidelines for the screening for asymptomatic coronary artery disease in diabetes

About 40% of diabetic patients with asymptomatic coronary artery disease (CAD) are missed on the basis of the current screening guidelines. Erectile Dysfunction (ED) is a powerful marker of asymptomatic CAD. Aim of the study is to evaluate whether ED can improve the effectiveness of the current guidelines for the screening of CAD in diabetes. From among 299 consecutive men with newly diagnosed type 2 diabetes without any apparent vascular complication, 293 (mean age 56.6±5.9 years) were enrolled. Among them, 219 did not have myocardial ischemia (NO CAD group) and 74 men had a coronary stenosis angiographically proven (CAD group). Five risk factors (RFs) of the current screening guidelines (hypertension, dyslipidemia, family history for CAD, smoking e micro/macroalbuminuria) and ED were assessed. ED was significantly more prevalent in the CAD than in the NO CAD group (37.8 versus 15.1%; P<0.001) and was a predictor of asymptomatic CAD (OR: 4.4; 95%CI: 2.1-9.0; P<0.001). If ED is added to the list of RFs, it can increase the sensitivity of the current guidelines from 62 to 89%, without a significant variation in specificity (from 60 to 57%). The negative predictive value can increase from 82 to 94%. ED can reduce from 37.84 to 10.81% the percentage of patients with silent CAD missed at the screening. This study first shows that ED can improve the effectiveness in discriminating diabetic men to screen for asymptomatic CAD, when it is added to the list of RFs of the current screening guidelines.     

Association of lipoprotein(a) levels and apolipoprotein(a) phenotypes with coronary artery disease in Type 2 diabetic patients and in non-diabetic subjects.

AIMS: We investigated whether in Type 2 diabetic patients lipoprotein(a) (Lp(a)) levels and apolipoprotein(a) (apo(a)) polymorphism are associated with angiographically documented coronary artery disease (CAD). We also examined whether there are differences in the distributions of Lp(a) levels and apo(a) phenotypes between CAD patients with and without diabetes. METHODS: A hundred and seven diabetic patients with CAD, 274 diabetic patients without CAD, 201 non-diabetic patients with CAD, and 358 controls were enrolled. RESULTS: Diabetic patients with CAD showed Lp(a) levels (21.2 +/- 17.7 vs. 15.1 +/- 17.8 mg/dl; P = 0.0018) and a percentage of subjects with at least one apo(a) isoform of low molecular weight (MW) (67.2% vs. 27.7%; P = 0.0000) significantly greater than diabetic patients without CAD. Multivariate analysis showed that in diabetic patients Lp(a) levels and apo(a) phenotypes were significantly associated with CAD; odds ratios (ORs) of high Lp(a) levels for CAD were 2.17 (1.28-3.66), while ORs of the presence of at least one apo(a) isoform of low MW were 5.35 (3.30-8.60). Lp(a) levels (30.2 +/- 23.7 vs. 21.2 +/- 17.7 mg/dl; P = 0.0005) and the percentage of subjects with at least one apo(a) isoform of low MW (87.0% vs. 67.2%; P = 0.0001) were significantly higher in CAD patients without than in those with diabetes. CONCLUSIONS: Our data suggest that Lp(a) levels and apo(a) phenotypes are independently associated with CAD in Type 2 diabetic patients; thus both these parameters may be helpful in selecting diabetic subjects at high genetic cardiovascular risk. However, Lp(a) levels and apo(a) polymorphism seem to be cardiovascular risk factors less important in diabetic than in non-diabetic subjects. Diabet. Med. 18, 589-594 (2001)     

Defect of a subpopulation of natural killer immune cells in Graves' disease and Hashimoto's thyroiditis: normalizing effect of dehydroepiandrosterone sulfate

BACKGROUND: The study of the natural killer (NK) immune compartment could provide important findings to help in the understanding of some of the pathogenetic mechanisms related to autoimmune thyroid diseases (Graves' disease (GD) and Hashimoto's thyroiditis (HT)). Within this context, it was suggested that alterations in NK cell cytotoxicity (NKCC) and NK production of cytokines might occur in subjects with GD and HT, whereas the normalization of NK functions could potentially contribute to the prevention of the onset or the progression of both diseases. OBJECTIVE: Due to the hypothesis of alterations in NK in autoimmune thyroid diseases, we were interested to evaluate NKCC in GD and HT patients and to modulate NK function and secretory activity with cytokines and dehydroepiandrosterone sulfate (DHEAS) in an attempt to normalize NK cell defect. DESIGN: We studied 13 patients with recent onset Graves' disease, 11 patients with Hashimoto's thyroiditis at first diagnosis and 15 age-matched healthy subjects. METHODS: NK cells were concentrated at a density of 7.75x10(6) cells/ml by negative immunomagnetic cell separation and validated by FACScan as CD16+/CD56+cells. NK cells were incubated with interleukin-2 (IL-2) and interferon-beta (IFN-beta) and co-incubated with DHEAS at different molar concentrations for measuring NKCC and the secretory pattern of tumor necrosis factor-alpha (TNF-alpha) from NK cells. RESULTS: Lower spontaneous, IL-2- and IFN-beta-modulated NKCC was demonstrated in GD and HT patients compared with healthy subjects (P<0.001). A decrease in spontaneous and IL-2-modulated TNF-alpha release from NK cells was also found in both groups of patients (P<0.001). The co-incubation of NK cells with IL-2/IFN-beta+DHEAS at different molar concentrations (from 10(-8) to 10(-5) M/ml/NK cells) promptly normalized NKCC and TNF-alpha secretion in GD and HT patients. CONCLUSIONS: A functional defect of a subpopulation of NK immune cells, involving both NKCC and the secretory activity, was demonstrated in newly-diagnosed GD and HT patients. This defect can be reversed by a dose-dependent treatment with DHEAS. The impairment of NK cell activity in autoimmune thyroid diseases could potentially determine a critical expansion of T/B-cell immune compartments leading to the generation of autoantibodies and to the pathogenesis of thyroid autoimmunity.