Cigarette smoking and hypertension Virdis, A; Giannarelli, C; Neves, M Fritsch ...
Current pharmaceutical design,
08/2010, Letnik:
16, Številka:
23
Journal Article
Recenzirano
Cigarette smoking is a powerful cardiovascular risk factor and smoking cessation is the single most effective lifestyle measure for the prevention of a large number of cardiovascular diseases. ...Impairment of endothelial function, arterial stiffness, inflammation, lipid modification as well as an alteration of antithrombotic and prothrombotic factors are smoking-related major determinants of initiation, and acceleration of the atherothrombotic process, leading to cardiovascular events. Cigarette smoking acutely exerts an hypertensive effect, mainly through the stimulation of the sympathetic nervous system. As concern the impact of chronic smoking on blood pressure, available data do not put clearly in evidence a direct causal relationship between these two cardiovascular risk factors, a concept supported by the evidence that no lower blood pressure values have been observed after chronic smoking cessation. Nevertheless, smoking, affecting arterial stiffness and wave reflection might have greater detrimental effect on central blood pressure, which is more closely related to target organ damage than brachial blood pressure. Hypertensive smokers are more likely to develop severe forms of hypertension, including malignant and renovascular hypertension, an effect likely due to an accelerated atherosclerosis.
Abstract Aim The present paper is a selective review on the methodology and clinical significance of techniques to assess specifically endothelial function, carotid mechanics and renal vascular ...function, particularly in the light of vascular dysfunction in metabolic syndrome and type 2 diabetes. Data synthesis Endothelial dysfunction appears to be earlier detectable in the microcirculation of patients with altered glucose metabolism, while it attains significance in the macro-circulation at more advanced disease stages. Smooth muscle cell dysfunction is now increasingly recognized to play a role both in the development of endothelial dysfunction and abnormal arterial distensibility. Furthermore, Impaired glucose metabolism affects carotid mechanics through medial calcification, structural changes in extracellular matrix due to advanced glycation and modification of the collagen/elastin material stiffness. The assessment of renal vascular function by dynamic ultrasound or magnetic resonance imaging has recently emerged as an appealing target for identifying subtle vascular alterations responsible for the development of diabetic nephropathy. Conclusions Vascular dysfunction represents a major mechanism for the development of cardiovascular disease in patients with abnormal glucose metabolism. Hence, the currently available non-invasive techniques to assess early structural and vascular abnormalities merit recommendation in this population, although their predictive value and sensitivity to monitor treatment-induced changes have not yet been established and are still under investigation.
Aims/hypothesis
Endothelium-derived factors are thought to be physiological modulators of large artery stiffness. The aim of the study was to investigate whether endothelial function could be a ...determinant of arterial stiffness in essential hypertensive patients, in relation with the concomitant presence of type 2 diabetes mellitus.
Methods
The study included 341 participants (84 hypertensive patients with and 175 without type 2 diabetes mellitus, 82 matched controls). Brachial artery endothelium-dependent flow-mediated dilation (FMD) was determined by high-resolution ultrasound and computerised edge detection system. Applanation tonometry was used to measure carotid–femoral pulse wave velocity (PWV).
Results
Hypertensive patients with diabetes had higher PWV (10.1 ± 2.3 m/s vs 8.6 ± 1.4 m/s,
p
< 0.001) and lower FMD (3.51 ± 2.07 vs 5.16 ± 2.96%,
p
< 0.001) than non-diabetic hypertensive patients, who showed impaired vascular function when compared with healthy participants (7.9 ± 1.6 m/s and 6.68 ± 3.67%). FMD was significantly and negatively correlated to PWV only in hypertensive diabetic patients (
r
= −0.456,
p
< 0.001), but not in hypertensive normoglycaemic patients (
r
= −0.088,
p
= 0.248) or in healthy participants (
r
= 0.008,
p
= 0.946). Multivariate analysis demonstrated that, in the diabetic group, FMD remained an independent predictor of PWV after adjustment for confounders (
r
2
= 0.083,
p
= 0.003). Subgroup analysis performed in non-diabetic hypertensive patients revealed that neither obesity nor the metabolic syndrome affected the relationship between FMD and PWV.
Conclusions/interpretation
Endothelial dysfunction is a determinant of aortic stiffness in hypertensive diabetic patients but not in hypertensive patients without diabetes. These results suggest that type 2 diabetes mellitus on top of hypertension might worsen arterial compliance by endothelium-related mechanisms.
Purpose
Several foods and nutrients have been independently associated with systolic (SBP) and diastolic (DBP) blood pressure values. This study aimed to evaluate the effects of combined dietary ...habits on SBP and DBP values in a large cohort of healthy adults, with a cross-sectional design. Adherence of participants to four a priori dietary patterns was considered: the Healthy Eating Index 2010 (HEI-2010); the Dietary Approaches to Stop Hypertension (DASH); the Greek Mediterranean Diet Score (MDS); and the Italian Mediterranean Index (IMI).
Methods
Overall, 13,597 volunteers (35–64 years) were enrolled in 1993–1998 in the EPIC-Florence cohort. Information on dietary habits, anthropometry, smoking status, education, physical activity habits, previous diagnosis of hypertension and SBP and DBP measurements were collected at baseline. Multivariate regression models were performed on 10,163 individuals (7551 women) after excluding subjects with prevalent hypertension.
Results
IMI, DASH and HEI-2010 were significantly and inversely associated with SBP and DBP values in the total population. The strongest association emerged between IMI and SBP (
β
− 1.80 excellent adherence vs low adherence, 95% CI − 2.99; − 0.61,
p
trend 0.001) and DBP (
β
− 1.12, 95% CI − 1.869; − 0.39,
p
trend 0.001) values. In sub-group analyses, an inverse association also emerged between IMI and SBP and DBP values among females and between DASH and DBP among males. MDS was not associated with SBP or DBP.
Conclusion
Overall, this study, carried out in a large cohort of healthy adults from Tuscany (Central Italy), showed inverse significant associations between specific a priori dietary patterns, identifying general models of health-conscious diet, and blood pressure values.
Abstract The endothelium plays a primary role in the modulation of vascular tone and structure, through production of the relaxing factor nitric oxide, which acts by protecting the vessel wall from ...the development of atherosclerosis and thrombosis. A dysfunctioning endothelium, characterized by reduced nitric oxide availability, can be a promoter of atherosclerosis. Ageing is a well-documented cardiovascular risk factor. One of the possible physiopathological mechanisms whereby increasing age may lead to cardiovascular damage is the promotion of endothelial dysfunction. In humans, age-related impairment in endothelium-dependent vasodilation has been well documented in different vascular districts and involves the impairment of nitric oxide activity secondary to oxidative stress generation. Regular physical training is an important non-pharmacological intervention which protects the vascular endothelium from ageing-related alterations and ameliorates the cardiovascular risk profile among the elderly population.
The measurement of the brachial artery diameter is frequently used in clinical studies for evaluating the flow-mediated dilation and, in conjunction with the blood pressure value, for assessing ...arterial stiffness. This paper presents a system for computing the brachial artery diameter in real-time by analyzing B-mode ultrasound images. The method is based on a robust edge detection algorithm which is used to automatically locate the two walls of the vessel. The measure of the diameter is obtained with subpixel precision and with a temporal resolution of 25 samples/s, so that the small dilations induced by the cardiac cycle can also be retrieved. The algorithm is implemented on a standalone video processing board which acquires the analog video signal from the ultrasound equipment. Results are shown in real-time on a graphical user interface. The system was tested both on synthetic ultrasound images and in clinical studies of flow-mediated dilation. Accuracy, robustness, and intra/inter observer variability of the method were evaluated
Third molar extraction is one of the most frequent interventions in dentistry. Nevertheless, there is scarce evidence on the host response of individuals with impacted or semi-impacted third molars ...and the possible effects of surgical removal. A case-control study of 40 patients was designed to evaluate 1) the differences in biomarkers of systemic inflammation, vascular function, and metabolism (high-sensitive C-reactive protein, lipids, fibrinogen, oxidative stress, and endothelial function analysis) and 2) the acute and short-term effects of surgical removal in patients with bilateral impacted or semi-impacted third molars compared to controls with no third molars. Patients undergoing third molar extraction exhibited greater levels of systemic inflammation, oxidative stress, and triglycerides than controls. Raised white blood cell counts as well as peaks of serum levels of C-reactive protein and fibrinogen were noticed in the first postoperative week. Three months after the extraction, all markers returned to baseline values. Malondialdehyde, an indicator of oxidative stress indicator, was significantly reduced after third molar removal. Semi-impacted or impacted third molars are associated with higher systemic inflammation, and their removal may represent a useful human model to study acute inflammation and determine beneficial systemic effects (ClinicalTrials.gov NCT03048175).
PDF