Biomedical subjects

John P Lekakis

Publications and source records attributed to John P Lekakis.

At least 19 recordsLinked to original sources

PubMed2007

Central blood pressures: do we need them in the management of cardiovascular disease? Is it a feasible therapeutic target?

It is well established that in young and healthy individuals central (aortic or carotid) systolic and pulse pressures are different from peripheral (brachial) corresponding pressures as a consequence of progressive changes in arterial stiffness and pressure wave reflections along the arterial tree. There is evidence indicating that in interventions with pharmaceutical and non-pharmaceutical agents, central pressures are subjected to greater changes than peripheral pressures, and they are more closely related to the pathophysiology of end-organ damage or cardiovascular risk. Therefore central blood pressures may be of higher clinical importance than peripheral pressures. The present review aims to provide an insight into the (patho)physiology of central blood pressures, to present the most accurate techniques for their estimation, and to discuss the available experimental and epidemiological data that support the emerging need for the evaluation of central blood pressures in clinical practice.

Aorta↗

PubMed2006

The relative impact of different measures of adiposity on markers of early atherosclerosis.

BACKGROUND: Although there are several methods available to assess adiposity, there is still controversy on the relative clinical utility of each of these methods. This study examines the relative impact of different measures of adiposity on markers of early atherosclerosis. In particular weight changes over time have been poorly assessed in this setting. METHODS: Eighty-six healthy individuals (31 men, age 36.5+/-8.9 years) with a wide range of body-mass index (28.7+/-7.0, 18.9-57.9 kg/m2) without hypertension, diabetes or smoking were examined. In addition to waist circumference and waist-to-hip ratio self-reported weight change since adolescence was also calculated. Ultrasonography was used to measure abdominal fat layers and their ratio. Flow-mediated dilatation of the brachial artery, serum levels of intercellular adhesion molecule (sICAM-1) and mean intima-media thickness of the carotid artery were measured as markers of early atherosclerosis. RESULTS: Stepwise multivariate regression analysis showed waist circumference and waist-to-hip ratio as the only independent predictor of flow-mediated dilatation. Waist circumference and weight change but not current body-mass index were independent predictors of intima-media thickness. These correlations were not influenced by ultrasonographically measured fat layers, C-reactive protein and basal insulin resistance. Body-mass index and weight gain were associated with sICAM-1 but not independently of basal insulin resistance and C-reactive protein. CONCLUSIONS: Waist circumference and weight gain were the strongest predictors of early atherosclerosis in a population of apparently healthy adults. The ultrasonographically measured fat layers did not provide additional information in this population.

Abdominal Fat↗

PubMed2006

Long-term prognostic role of flow-mediated dilatation of the brachial artery after acute coronary syndromes without ST elevation.

Coronary endothelial vasodilator dysfunction is associated with increased cardiac events; the close relation between coronary vasomotor dysfunction and brachial artery vasoreactivity has been previously described. This study assessed the prognostic value of noninvasively assessed brachial artery vasoreactivity in survivors of acute coronary syndromes without ST-segment elevation. We examined 98 men (63.1 +/- 10.8 years) who were referred to our hospital for acute coronary syndromes without ST-segment elevation. Brachial artery endothelium-dependent flow-mediated dilation (FMD) and endothelium-independent nitrate-mediated dilation were examined in all patients using high-resolution echocardiographic Doppler ultrasound within 24 hours of admission. Plasma malondialdehyde, a marker of oxidative stress, and left ventricular ejection fraction were also assessed. Twenty-seven patients underwent coronary revascularization. Patients were followed for 24.8 +/- 5.9 months. Cardiovascular death, myocardial infarction, stroke, and unstable angina were designated as cardiovascular events (CEs). Twenty CEs were recorded. Kaplan-Meyer analysis showed that patients with FMD <1.9% (tertile 1 of FMD values) were more likely to have CEs than those with FMD >1.9% (log rank 5.29, p = 0.021). Multivariate Cox regression analysis showed that FMD <1.9% predicted CEs with an adjusted hazard ratio of 3.035 (95% confidence interval 1.148 to 8.023, p = 0.025) after adjustment for age, risk factors, troponin T, ejection fraction, revascularization procedures, number of diseased vessels, and medication. In conclusion, endothelium-dependent dilation of the brachial artery is a strong independent predictor of adverse outcome in survivors of acute coronary syndromes without ST-segment elevation.

Acute Disease↗

PubMed2006

Assessment of vascular wall shear stress and implications for atherosclerotic disease.

Mechanical characteristics of circulation and vasculature, such as blood flow in combination with geometrical features, participate in the generation of several pathophysiological processes, such as development of blood vessel structure, chronic vessel tone regulation, atherosclerosis and others. We aim to briefly describe the basic mechanical and haemodynamic phenomena related to the forces applied to arterial walls, especially shear stresses and the shear-induced physiologic and pathophysiologic processes focusing on those related to atherosclerotic disease.

Atherosclerosis↗

PubMed2006

Abnormal endothelial function in female patients with hypothyroidism and borderline thyroid function.

BACKGROUND: It has been suggested that hypothyroidism is associated with an increased risk for cardiovascular disease. The aim of this study was to assess non-invasively NO-dependent endothelial function of resistance arteries in subjects with hypothyroidism of varying severity. METHODS: Ninety-six female subjects (aged: 42+/-13 years) comprised the study population. Subjects were divided into five groups based on TSH levels at presentation: Group 0 (n=23) with TSH: 0.3-2.0 microU/ml, Group 1 (n=22) with TSH: 2.1-4.0 microU/ml (upper normal), Group 2 (n=18) with TSH: 4.1-10 microU/ml (subclinical hypothyroidism), Group 3 (n=22) with TSH >10 microU/ml (overt hypothyroidism). One additional group with well-controlled hypothyroidism on L-thyroxine therapy (Group 4, n=11, TSH: 0.3-2.0 microU/ml) was also studied. Endothelial function of resistance arteries was assessed by measuring forearm blood flow response during reactive hyperemia utilizing venous occlusion strain-gauge plethysmography. RESULTS: Duration of reactive hyperemia was significantly different among groups of subjects with varying hypothyroidism (83.7+/-58.3 s, 53.2+/-35.7 s, 52.8+/-47.5 s, 12.9+/-13.3 s and 69.5+/-26.2 s in Groups 0, 1, 2, 3 and 4, respectively, p<0.001, ANOVA). Duration of reactive hyperemia was significantly shorter in subjects with upper normal TSH values (Group 1) compared to controls (53.2+/-35.7 s vs. 83.7+/-58.3 s, p=0.013), while it was comparable to that of subjects with subclinical hypothyroidism (Group 2) (52.8+/-47.5 s). However, duration of reactive hyperemia in Group 1 was significantly longer compared to Group 3 (overt hypothyroidism) (53.2+/-35.7 s vs. 12.9+/-13.3 s, p=0.002). Similarly, duration of reactive hyperemia in subjects with subclinical hypothyroidism was significantly longer compared to subjects with overt hypothyroidism (52.8+/-47.5 s vs. 12.9+/-13.3 s, p=0.003). Duration of reactive hyperemia in Group 4 (well-controlled hypothyroidism on L-thyroxine therapy) did not differ significantly compared to controls. There was a highly significant linear correlation between duration of reactive hyperemia and TSH (r=-0.383, p<0.001). CONCLUSION: Endothelial dysfunction was detected in the microvasculature of patients with hypothyroidism. Duration of reactive hyperemia decreased with increasing TSH levels. Since endothelial dysfunction is a factor leading to atherosclerosis, this abnormality may partly explain predisposition of patients with thyroid failure to cardiovascular disease.

Adult↗

PubMed2006

Circadian variation of arterial pressure wave reflections.

BACKGROUND: Various factors are implicated in the circadian pattern of cardiovascular vulnerability. The exact mechanisms involved in the peak incidence of cardiovascular events occurring during the early morning hours after awaking are not completely known. The purpose of our study was to investigate the circadian variation of timing and intensity of wave reflections in healthy individuals and to test the hypothesis that significant changes occur during the day. METHODS: Thirteen healthy non-smokers (seven women and six men, mean age 40.7 +/- 16.5 years) were examined. Aortic pulse wave analysis was performed to estimate surrogates of wave reflections intensity (augmentation index [AIx]) and timing. Twelve measurements separated by 1-h intervals were performed from 8 am to 7 pm each study day. RESULTS: Analysis of variance for repeated measures indicated significant changes during the 12-h period for heart rate corrected AIx (P = .033) and heart rate (P = .035). The AIx was maximal at 8 am within 1-h after awaking (17% +/- 3.6%); it was gradually diminished until 3 pm (9% +/- 4.1%) and again increased to a second (albeit lower) peak value during the late afternoon (7 pm). CONCLUSIONS: It is possible that the increased intensity of reflected waves occurring during the early morning in combination with the rising trend of blood pressure and heart rate at the same time results in an aggravated left ventricular afterload and an increase in myocardial oxygen demand. The morning-related enhancement of wave reflections may have potential implications for the increased risk for cardiovascular events during the early morning, which remains to be clarified.

Adult↗

PubMed2006

Arterial wave reflection is associated with severity of extracoronary atherosclerosis in patients with coronary artery disease.

BACKGROUND: Arterial wave reflection is a major determinant of left ventricular function, coronary perfusion and cardiovascular risk. We investigated whether arterial wave reflection may detect atherosclerosis of peripheral arteries in patients with documented coronary artery disease (CAD). METHODS: Radial artery applanation tonometry and pulse wave analysis was performed in 184 patients with documented CAD at coronary angiography; central blood pressures and augmentation index (AI) were measured. Ankle-brachial (ABI) index and intima-media thickness (IMT) were used as indices of atherosclerosis of the lower limbs and the carotid arteries respectively. RESULTS: Patients with abnormal IMT (> 0.7 mm, first tertile) or ABI (< 0.94, first tertile) had higher AI than patients with lower IMT or higher ABI (24 +/- 17 versus 17 +/- 16% and 23 +/- 18 versus 18 +/- 13%, respectively, P < 0.05). In multivariate analysis, increasing AI was associated with age, female gender, heart rate, mean blood pressure, hyperlipidaemia, and use of statins (regression coefficient (beta) = 0.50, beta = 0.15, beta = -0.60, beta = 0.23, beta = 0.16 and beta = -0.14, respectively, P < 0.05). Increasing AI was associated with an adjusted-odds ratio of 1.035 [95% confidence interval (CI), 1.005-1.066], P = 0.02 for an abnormal IMT and of 1.08 (95% CI, 1.024-1.146), P = 0.005 for ABI after adjustment for age, gender, heart rate, height, blood pressure, atherosclerotic risk factors, obesity and medication. No relation was found between AI and Gensini score or for the number of diseased coronary vessels. CONCLUSION: Augmentation index is a marker of extensive extracoronary atherosclerosis in patients with CAD.

Aged↗

PubMed2006

Genetic variations of the endothelial nitric oxide synthase gene are related to increased levels of C-reactive protein and macrophage-colony stimulating-factor in patients with coronary artery disease.

It was the objective of this study to investigate the relation between nitric oxide synthase (NOS3) gene polymorphisms, vascular inflammation, endothelial function, and atherosclerosis. We examined the effects of a variable nucleotide tandem repeats (VNTR) in intron 4, G894T in exon 7 and T-786C at the promoter region of NOS3 on i) C-reactive protein (CRP) and macrophage-colony stimulating-factor (MCSF), and ii) augmentation index (AI) measured by pulse-wave analysis , flow-mediated dilation (FMD) of the brachial artery, intima-media thickness (IMT) of the carotid and femoral artery using ultrasonography and ankle-brachial index (ABI) in 122 patients with chronic coronary artery disease (CAD) who underwent coronary angiography. MCSF and CRP were increased in patients withT-786C (77/122) or VNTR (40/122) allele compared to those without (F = 10.8, p = 0.002 and F = 3.8, p = 0.04 for T-786C and F = 3.65, p = 0.04 and F = 3.2 p = 0.049 forVNTR), even after adjustment for traditional risk factors and medication. Patients with combination of VNTR and T-786C (31/122) had higher MCSF or CRP than patients with one or none of these alleles (p < 0.05). Among patients with T-786C, those with MCSF>262 pg/ml or CRP>3.2 mg/l (n = 33/77) had a higher femoral and carotid IMT and number of plaques in the peripheral arteries than those with lower values of these inflammatory indices (p < 0.05). Patients with MCSF >262 pg/ml had also lower FMD and higher Gensini score than those with lower MCSF (p < 0.05). The intron 4-VNTR and T-786C mutation of NOS3 gene enhance the inflammatory process in patients with chronic CAD.

C-Reactive Protein↗

PubMed2005

Divergent effects of rofecoxib on endothelial function and inflammation in acute coronary syndromes.

BACKGROUND: The safe use of selective inhibitors of cyclooxygenase-2 in patients with cardiovascular disease has been questioned because of studies showing an increased risk of cardiac events. We examined the short-term effect of rofecoxib, a selective cyclooxygenase-2 inhibitor, on endothelial function, oxidative damage and inflammation in patients with acute coronary syndromes without ST-segment elevation. METHODS: Forty-three patients with acute coronary syndromes without ST-segment elevation participated in the study. Flow-mediated dilatation (FMD), nitrate-mediated dilatation (NMD) of the brachial artery, malondialdehyde, a marker of lipid peroxidation, C-reactive protein, an acute phase marker of inflammation, and interleukin-6, a proinflammatory cytokine, were measured within 24 h of admission and a week later. Patients were randomized to receive for a week 100 mg aspirin daily with either 25 mg of rofecoxib (n=21) or placebo (n=22) orally once daily. RESULTS: Malondialdehyde, C-reactive protein and interleukin-6 levels were reduced in the rofecoxib group (p=0.04, p=0.003 and p=0.02 respectively) while they remained unchanged in the placebo group after 1 week of treatment. FMD and NMD changes in both groups were not statistically different. CONCLUSIONS: Co-administration of rofecoxib with low-dose aspirin decreases inflammatory and oxidative indices but does not improve endothelial function. The lack of improvement in FMD despite the improvement in inflammation and oxidative stress could be viewed in association to the recent observations on the adverse effects of COX-2 inhibition on the cardiovascular system.

Acute Disease↗

PubMed2005

Transmission of calibration errors (input) by generalized transfer functions to the aortic pressures (output) at different hemodynamic states.

BACKGROUND: Aortic pressure waveforms are calculated non-invasively by applying generalized transfer functions (GTF) to tonometric radial pressure waveforms. Input errors mainly during acquisition and calibration of tonometric pressures are "transferred" to aortic pressure calculation. The present study aimed to quantify the proportion of specific input errors which is "transferred" by the GTFs in a wide range of hemodynamic conditions and for different error combinations in brachial systolic (SBP) and diastolic (DBP) blood pressure measurements. METHODS: Aortic pulse wave analysis was performed in 103 subjects (52 normotensive and 51 untreated hypertensive) by the SphygmoCor System. Each pressure waveform was initially calibrated by sphygmomanometrical brachial pressures. Isolated, parallel and reverse errors in brachial SBP/DBP from -10 to +10 mmHg were simulated, by recalibration of the recorded radial pressure waveforms, inducing specific "errors" of GTF-input values. For every recalculated aortic SBP and DBP, the difference from the initial estimated value was considered to represent the "transferred error" to the aortic pressure estimation. RESULTS: Parallel errors by +/-5 mmHg in both SBP and DBP resulted to an identical change in GTF-derived aortic pressures, as expected. When an overestimation in SBP by 5 mmHg and an underestimation in DBP by -5 mmHg occurred (reverse errors), almost 56% of this error (approximately 2.8 mmHg) was transferred. An isolated error in brachial SBP by +/-5 mmHg was transmitted by 76% ( approximately 3.8 mmHg) to GTF-derived aortic SBP. In subjects with mean blood pressure>117 mmHg or with heart rates<74 bpm, a greater percent of the calibration error was transferred to GTF-derived blood pressures. CONCLUSIONS: Input errors in brachial pressure values result in a quantifiable effect on transfer function output (aortic pressures). The percent of the "error transfer" by the GTFs depends on heart rate and BP levels, which should be taken into account when applying GTFs at populations with different hemodynamic conditions.

Adult↗

PubMed2005

Arterial stiffness is increased in subjects with hypothyroidism.

BACKGROUND: The association between hypothyroidism and increased vascular resistance, arterial wall thickening and endothelial dysfunction is well recognized. The aim of the present study was to examine if hypothyroid subjects have increased arterial stiffness, a risk factor for cardiovascular morbidity and mortality. METHODS: Sixty-five subjects (59 females and 6 males) with normal thyroid function or hypothyroidism of varying degree were investigated by radial artery applanation tonometry and pulse wave analysis, for evaluation of arterial stiffness. RESULTS: Serum TSH values were positively correlated with central systolic blood pressure (r=0.258, p=0.037), central pulse pressure (r=0.316, p=0.010), augmentation pressure (r=0.299, p=0.015) and negatively with reflection time index (RTI), which indicates the pressure wave velocity (r=-0.311, p=0.012). Hypothyroid patients presented higher central systolic pressure and pulse pressure, higher augmentation pressure and lower RTI, indicating increased arterial stiffness in these subjects. RTI was independently related to age, central systolic pressure and TSH. Mild changes of arterial stiffness were observed even in subjects with TSH range 2.01-4.0 muU/ml suggesting that this group may have an early stage of mild thyroid failure. CONCLUSIONS: Hypothyroidism, even in the subclinical stage, is associated with changes in arterial stiffness. The observed abnormalities in arterial stiffness may have detrimental effects on left ventricular function and coronary perfusion in hypothyroid subjects.

Adult↗

PubMed2005

Arterial stiffness assessed by pulse wave analysis in essential hypertension: relation to 24-h blood pressure profile.

BACKGROUND: Arterial stiffness is a risk factor for cardiovascular morbidity and mortality and appears to be increased in arterial hypertension. The purpose of the present study was to relate systemic arterial stiffness assessed by pulse wave analysis to variables of 24-h ambulatory blood pressure monitoring (ABPM) in patients with essential hypertension. METHODS: Seventy-two subjects with untreated mild to moderate arterial hypertension underwent evaluation with 24-h ambulatory blood pressure monitoring. In the same subjects, applanation tonometry and pulse wave analysis was performed for evaluation of systemic arterial stiffness expressed as augmentation index and estimated aortic pulse wave velocity. RESULTS: Clinic systolic blood pressure, mean heart rate during 24-h blood pressure monitoring and height were independent predictors of augmentation index and estimated aortic pulse wave velocity. The 41 patients with blunted reduction in nighttime blood pressure (nondippers) showed higher mean systolic blood pressure (p=0.02), lower systolic and diastolic blood pressure variability (p<0.001), higher pulse pressure during 24-h monitoring (p=0.05) and higher estimated aortic pulse wave velocity (p=0.03), indicating stiffer arteries in this group. CONCLUSIONS: These results suggest that blood pressure change from day- to nighttime is an important determinant of arterial stiffness assessed by pulse wave analysis; this association could contribute to the higher cardiovascular risk in nondippers.

Blood Pressure Monitoring, Ambulatory↗

PubMed2005

Intima-media thickness score from carotid and femoral arteries predicts the extent of coronary artery disease: intima-media thickness and CAD.

OBJECTIVES: In the present study we measured carotid and femoral intima-media thickness (IMT) by B-Mode ultrasonography, as well as angiographic extent and severity of coronary artery disease in patients referred for coronary arteriography, to assess the relation between individual IMT, scores incorporating IMT from the carotid and femoral arteries and the extent and severity of coronary artery disease. METHODS: Two hundred and two patients referred for elective coronary angiography underwent ultrasound imaging of both carotid and femoral arteries for IMT measurements. An IMT score was developed as the number of sites with abnormal IMT (range 0-8). Multiple regression analysis indicated that IMT score was independently related to Gensini score, age and glucose levels. A high risk IMT score predicted an extended coronary artery disease although a low or medium risk IMT score cannot exclude the possibility of multivessel disease. Also, a high risk group could predict the performance of revascularization procedures and all cardiovascular events during a follow-up of 14.5 +/- 2.4 months. CONCLUSIONS: IMT incorporating data from common and internal carotid artery, carotid bifurcation and femoral artery are well correlated with the extent of coronary atherosclerosis, much better than individual IMT. Patients with high IMT score usually have multivessel coronary artery disease and are at increased risk for subsequent cardiovascular events.

Age Factors↗

PubMed2005

Effect of nebivolol and atenolol on brachial artery flow-mediated vasodilation in patients with coronary artery disease.

Endothelial dysfunction is considered to be the first step in atherogenesis as well as a predictor of adverse cardiovascular events in patients with coronary artery disease (CAD), while endothelial function improvement is associated with improved clinical outcome. Nebivolol is a beta1-adrenoreceptor antagonist with an independent beneficial action on endothelial function, increasing nitric oxide bioavailability. The aim of the present study was to examine the effects of nebivolol on endothelial function in the brachial artery in patients with CAD compared with another selective beta1 adrenergic receptor antagonist, atenolol. Thirty-five patients with stable CAD were randomized to receive either 5 mg nebivolol (n = 17) or 50 mg atenolol (n = 18) daily for 4 weeks. Each patient underwent measurement of endothelial function by means of flow-mediated dilatation (FMD) of the brachial artery before and after 4 weeks of treatment. All vasoactive drugs and cardiovascular risk factors were comparable in the two groups. No significant differences were observed between the two groups at baseline in FMD. In the atenolol group FMD remained unchanged at the end of the 4-week treatment, but in patients treated with nebivolol FMD showed a significant increase by the end of the treatment period (3.9 +/- 2.7% vs. 5.6 +/- 2.9%, p = 0.047) leading to a significantly higher value compared to patients treated with atenolol (5.6 +/- 2.9% vs. 3.4 +/- 3.2%, p = 0.041).Beta(1) blockade by nebivolol but not atenolol improves endothelial dysfunction in patients with CAD, an effect that might further reduce the risk for cardiovascular events in patients with CAD.

Adrenergic beta-Antagonists↗

PubMed2005

Acute effects of caffeine on arterial stiffness, wave reflections, and central aortic pressures.

Caffeine is considered to be the most widely consumed pharmacologic substance in the world. Several recent sources of evidence suggest that caffeine, besides its well-established pressor effects, provokes further alterations in arterial stiffness, wave reflections, and especially aortic blood pressures, which are often overlooked. The increasing evidence regarding the prognostic value of the latter cardiovascular factors prompted us to seek additional information concerning the relationship of aortic blood pressures to caffeine consumption. The main purpose of the present review was to evaluate the acute influence of caffeine on arterial stiffness, wave reflections, and central systolic pressures, which are involved in the pathogenesis and prognosis of cardiovascular diseases. Current evidence supports the hypothesis that caffeine influences the cardiovascular system at least acutely, not only through a peripheral blood pressure elevation but also through an increase in arterial stiffness and an enhancement of arterial wave reflections. Moreover, it seems that peripheral pressure measurements might have underestimated caffeine pressor effects, as a significantly greater response is observed in aortic pressures. The mechanisms explaining these effects of caffeine are not always clear, and neither is the role of caffeine in cardiovascular risk. However, it is concluded that strategies aiming at the control of dietary caffeine consumption merit serious consideration.

Aorta↗

PubMed2005

Red wine acutely induces favorable effects on wave reflections and central pressures in coronary artery disease patients.

BACKGROUND: To investigate red wine's acute effects on aortic pressures and arterial stiffness in patients with coronary artery disease (CAD). METHODS: Fifteen patients with CAD were recruited in a double-blind, cross-over study, which was comprised of 2 study days. Each volunteer consumed either 250 mL of regular or 250 mL of dealcoholized red wine. Wave reflections, expressed as augmentation index (AIx), as well as central and peripheral blood pressures (BP) were assessed at fast and 30, 60, and 90 min postprandially. RESULTS: Both regular and dealcoholized red wine caused a significant decrease in AIx by 10.5% +/- 1.4% (P = .001) and 6.1% +/- 1.4% (P = .011), respectively, whereas no significant change was induced in mean BP and timing of wave reflections expressing pulse wave velocity. Peripheral systolic BPs remained unaltered in both beverages, whereas a significant decrease in peripheral and central diastolic BPs was observed after the dealcoholized red wine consumption (P = .03 and P = .035, respectively). Central systolic BP was decreased after the consumption of regular (-7.4 +/- 2.4 mm Hg, P = .05) and dealcoholized red wine (-5.4 +/- 2.7 mm Hg, P = .019). CONCLUSIONS: Both types of red wine provoked favorable acute effects on wave reflections and central systolic pressures, whereas no such effect was evident at the brachial artery. Therefore, these findings could be attributed mainly to red wine antioxidant substances, rendering it a possible means of at least acute attenuation of increased wave reflections, arterial stiffness, and central pressures in patients with coronary artery disease.

Adult↗

PubMed2005

Effect of coffee on endothelial function in healthy subjects: the role of caffeine.

Coffee is one of the most widely used pharmacologically active beverages. The present study was designed to evaluate the acute effect of coffee ingestion on endothelial function in healthy individuals, and the potential role of caffeine. We studied 17 healthy young adults (28.9+/-3.0 years old; nine men), who were regular non-heavy coffee drinkers. The endothelial performance was estimated by endothelium-dependent FMD (flow-mediated dilatation) of the brachial artery before and 30, 60, 90 and 120 min after ingestion of a cup of caffeinated coffee (80 mg of caffeine) or the corresponding decaffeinated beverage (< 2 mg of caffeine) in two separate sessions, following a randomized single-blind cross-over design. There was no difference in baseline FMD values between the two sessions [7.78 compared with 7.07% after caffeinated and decaffeinated coffee respectively; P = NS (not significant)]. Caffeinated coffee led to a decline of FMD (7.78, 2.86, 2.12, 4.44 and 4.57% at baseline, 30, 60, 90 and 120 min respectively; P < 0.001). This adverse effect was focused at 30 (P = 0.004) and 60 min (P < 0.001). No significant effect on FMD was found with the decaffeinated coffee session (7.07, 6.24, 5.21, 7.41 and 5.20%; P = NS). The composite effect of the type of coffee consumed over time on FMD was significantly different (P = 0.021). In conclusion, coffee exerts an acute unfavourable effect on the endothelial function in healthy adults, lasting for at least 1 h after intake. This effect might be attributed to caffeine, given that decaffeinated coffee was not associated with any change in the endothelial performance.

Adult↗

PubMed2004

Pulse pressure in acute stroke is an independent predictor of long-term mortality.

The management of blood pressure (BP) during the acute phase of stroke remains a matter of debate. The aim of the present study was to evaluate a possible association between long-term mortality and BP values in acute stroke by means of BP monitoring. We studied a consecutive series of 198 first-ever acute stroke patients. BP monitoring was initiated in all subjects within 24 h of ictus. One year after stroke onset, 34 (17.7%) patients had died. Multivariate Cox regression analysis revealed only age, level of consciousness on admission, lacunar stroke and 24-hour pulse pressure (24-hour PP) as significant outcome predictors. The hazards ratio for 1-year mortality associated with every 10 mm Hg increase in 24 h PP was 1.39 (95% CI: 1.04-1.86, p = 0.028). The present results demonstrate that increasing 24-hour PP levels in patients with acute stroke are independently associated with higher long-term mortality. This may have implications in acute stroke BP management and warrants further investigation.

Aged↗