The extent of target-organ damage has been positively associated with the magnitude of blood pressure (BP) variability in essential hypertension. However, the clinical implications of the rate of BP ...changes have never been investigated. We evaluated the possible association between the 24-hour time rate of systolic blood pressure (SBP) variation derived from computerized analysis of ambulatory BP monitoring (ABPM) data and the extent of common carotid artery intima-media thickness (CCA-IMT) in normotensive (n=237) and in uncomplicated hypertensive subjects (n=284). No antihypertensive and lipid-lowering treatment had ever been administered in any of the 521 subjects who underwent ABPM on a usual working day. The time rate of SBP variation was computed as the first derivative of the SBP values against time. The 24-hour rate of SBP variation was significantly (p<0.001) higher in hypertensive (0.609mmHg/min, 95%CI:0.596–0.622) than in normotensive individuals (0.566mmHg/min, 95%CI:0.554–0.576) even after adjusting for baseline characteristics, day-night BP changes, 24-hour heart rate (HR), SBP- and HR variability. In the hypertensive subgroup, the multiple linear regression models revealed independent determinants of CCA-IMT in the following rank order: age (p<0.001), 24-hour time rate of SBP variation (p<0.001), smoking (p=0.002), male gender (p=0.008) and triglycerides (p=0.017). Age (p<0.001) and 24-hour time rate of SBP variation (p=0.015) were the only significant determinants of CCA-IMT in normotensive individuals. A 0.1mmHg/min increase in the 24-hour rate of SBP variation correlated to an increment of 0.024mm (95%CI:0.005–0.042) and 0.026mm (95%CI:0.013–0.040) in the CCA-IMT of the normotensive and hypertensive subjects respectively even after adjustment for all baseline characteristics and other ABPM parameters. Thus, the rate of BP fluctuations is greater in hypertensive patients and correlates to CCA intima-media thickening. These findings indicate that steeper BP variations may produce a greater stress on the vessel wall and consequently result in medial hypertrophy of the large arteries.
Hyperhomocysteinemia has been recognised as an independent cardiovascular risk factor, while statins have been reported to have pleiotropic effects other than lipid lowering. In our study we sought ...to evaluate the possible effect of short-term administration of simvastatin on homocysteine (Hcy) and other established serum proatherogenic and inflammatory markers in essential hypertensive patients. Our study population consisted of 18 untreated mild essential hypertensive patients (9 men, mean age: 51.2±10.9 years, office blood pressure = 149/96 mmHg). All subjects received simvastatin (40mg/day) for a period of 1 month. Venous blood samples were drawn before and after the period of treatment with simvastatin in order to evaluate lipid, lipoprotein-a (Lp-a), apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), fibrinogen, uric acid, homocysteine, folic acid, vitamin B12, high sensitivity-CRP (hsCRP) levels, by standard methodology. For the pooled population BMI was 27.2±3.6 kg/m2, left ventricular mass index was 106±35.1 g/m2, relative wall thickness was 0.45±0.07 and hsCRP levels were 1.5±0.3 mg/l. After 1 month on simvastatin, there was a significant reduction in total cholesterol (215.1±40.7 vs 156.0±29.2 mg/dl, p<0.001), triglycerides (114.1±30.9 vs 89.6±27.8 mg/dl, p<0.05), LDL (141.4±29 vs 89.6±21.6 mg/dl, p<0.001), ApoB (101.6±19.2 vs 71.8±15 mg/dl, p<0.001), uric acid (5.8±1.2 vs 5.4±1.1 mg/dl, p<0.05), homocysteine (13.6±7.3 vs 12.7±7.4 μmol/l, p<0.05). In all subjects, apoA1 and hs-CRP did not exhibit any statistically significant attenuation (p=NS, for all cases). Moreover, the reduction of Hcy serum levels was not correlated with the observed reductions in total cholesterol, triglycerides, LDL, ApoB and uric acid values (p=NS, for all cases). Even in newly diagnosed essential hypertensive subjects, short-term administration of simvastatin resulted in a significant and independent attenuation of Hcy serum levels. These findings may elucidate the diverse pathophysiological mechanisms by which statins reduce cardiovascular risk, in this setting.
Statins have been reported to improve blood pressure control in essential hypertensive subjects via diverse pathophysiological mechanisms, while salt sensitivity is an emerging cardiovascular risk ...factor. In this study, we sought to investigate the possible effects of short-term administration of simvastatin on blood pressure levels in salt sensitive and salt resistant essential hypertensive subjects. Eighteen untreated mild essential hypertensive patients (9 men, age 51.2±10.9 years) were screened for salt sensitivity by means of an established protocol. All subjects underwent 24h ambulatory BP monitoring before and after 1 month of treatment with simvastatin (40mg/day). Venous blood samples were drawn before and after statin administration period for determination of lipid, lipoprotein-a, apolipoprotein A1 and apolipoprotein B levels. For the pooled population BMI was 27.2±3.6 kg/m2, left ventricular mass index was 106±35.1 g/m2 and relative wall thickness was 0.45±0.07. Four patients were classified as salt sensitive (SS) (2 men, 60±9 years), while 14 were salt resistant (SR) (7 men, 60±10 years). After 1 month on simvastatin, only SS patients, presented significant reductions in office systolic BP (155±12.9 vs 130±18.2 mmHg, p<0.05), 24-h diastolic BP (85.9±5.7 vs 76.3±4.3 mm Hg, p<0.05), 24-h mean BP (104.4±5.1 vs 93.3±7.5 mm Hg, p<0.05), daytime diastolic BP (89.1±7.6 vs 78.9±6 mm Hg, p<0.05), daytime mean BP (107.5±8.5 vs 95.1±8.3 mm Hg, p<0.05), while patients in the SR group did not exhibit any significant reduction in 24h BP levels (p=NS). Moreover, there was no correlation between the reductions of 24h BP in the SS group and the reductions of the lipid parameters (p=NS). In newly diagnosed essential hypertensive subjects, short-term administration of simvastatin resulted in a significant attenuation of BP values in salt sensitive hypertensives, independently of lipid lowering, suggesting a possible link between salt sensitivity and the pleiotropic mechanisms of statins action. These findings suggest that salt sensitive patients may benefit more from the pleiotropic effects of statins, in the same setting.
Several serum markers have been recognized as risk factors for target organ damage, while carotid intima-media thickness (IMT) has been established as an independent risk factor for cardiovascular ...events. In our study, we sought to validate the measurement of several biochemical risk factors as markers of carotid atherosclerosis in essential hypertensive subjects. This study included 24 untreated, mild essential, non-smokers hypertensive patients (13 men, mean age: 50 ±11.7 years) who underwent 24h ambulatory blood pressure monitoring in order to exclude white-coat hypertension. All subjects underwent B-mode ultrasonography of the carotid arteries to determine IMT and the presence of atheroma plaques of the common and internal carotid artery and carotid bulb. Venous blood samples were drawn from all participants in order to evaluate lipid and lipoprotein-a (Lp-a), apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), fibrinogen, uric acid, homocysteine and hsCRP levels, by standard methodology. For the pooled population, BMI was 27.6±5.1 kg/m2, cholesterol was 211.2±43.3 mg/dl, triglycerides were 115±56.2 mg/dl, HDL was 57.1±15 mg/dl, LDL was 139±31 mg/dl, Lp-a was 46±78 mg/dl, ApoA1 levels were 124.1±15.2 mg/dl, ApoB was 101.6±18.7, hs-CRP levels were 2.16±2 mg/l, fibrinogen was 270.8±49 mg/dl, uric acid levels were 5.8±1.4 mg/dl, homocysteine was 13.2±6.2 μmol/l. In the univariate model, IMT of the internal carotid artery was correlated with levels of triglycerides (r=0.432, p=0.039), uric acid (r=0.610, p=0.002), homocysteine (r=0.507, p=0.014) and ApoA1 (r=-0.457, p=0.028). Furthermore, in stepwise regression analysis only serum levels of uric acid and homocysteine remained significant after adjustment for all parameters analyzed (p=0.002 and p=0.016 respectively). In essential hypertensive subjects, serum levels of uric acid and homocysteine are closely related to carotid IMT, independently of a wide range of established proatherogenic and inflammatory mediators.
Several studies have addressed the epidemiology of community-associated Staphylococcus aureus (CA-SA) in Europe; nonetheless, a comprehensive perspective remains unclear. In this study, we aimed to ...describe the population structure of CA-SA and to shed light on the origin of methicillin-resistant S. aureus (MRSA) in this continent.
A total of 568 colonization and infection isolates, comprising both MRSA and methicillin-susceptible S. aureus (MSSA), were recovered in 16 European countries, from community and community-onset infections. The genetic background of isolates was characterized by molecular typing techniques (spa typing, pulsed-field gel electrophoresis and multilocus sequence typing) and the presence of PVL and ACME was tested by PCR. MRSA were further characterized by SCCmec typing. We found that 59% of all isolates were associated with community-associated clones. Most MRSA were related with USA300 (ST8-IVa and variants) (40%), followed by the European clone (ST80-IVc and derivatives) (28%) and the Taiwan clone (ST59-IVa and related clonal types) (15%). A total of 83% of MRSA carried Panton-Valentine leukocidin (PVL) and 14% carried the arginine catabolic mobile element (ACME). Surprisingly, we found a high genetic diversity among MRSA clonal types (ST-SCCmec), Simpson's index of diversity = 0.852 (0.788-0.916). Specifically, about half of the isolates carried novel associations between genetic background and SCCmec. Analysis by BURP showed that some CA-MSSA and CA-MRSA isolates were highly related, suggesting a probable local acquisition/loss of SCCmec.
Our results imply that CA-MRSA origin, epidemiology and population structure in Europe is very dissimilar from that of USA.
Currently, surveillance of livestock-associated meticillin-resistant
(LA-MRSA) in humans in Europe is not systematic but mainly event-based. In September 2014, the European Centre for Disease ...Prevention and Control (ECDC) initiated a questionnaire to collect data on the number of LA-MRSA from human samples (one isolate per patient) from national/regional reference laboratories in European Union/European Economic Area (EU/EEA) countries in 2013. Identification of LA-MRSA as clonal complex (CC) 398 by multilocus sequence typing (MLST) was preferred, although surrogate methods such as
-typing were also accepted. The questionnaire was returned by 28 laboratories in 27 EU/EEA countries. Overall, LA-MRSA represented 3.9% of 13,756 typed MRSA human isolates, but it represented ≥ 10% in five countries (Belgium, Denmark, Spain, the Netherlands and Slovenia). Seven of the reference laboratories did not type MRSA isolates in 2013. To monitor the dispersion of LA-MRSA and facilitate targeted control measures, we advocate periodic systematic surveys or integrated multi-sectorial surveillance.
PDF
