Biomedical subjects

Gérard M London

Publications and source records attributed to Gérard M London.

At least 19 recordsLinked to original sources

PubMed2007

Local shear stress and brachial artery functions in end-stage renal disease.

Physiologic laminar shear stress (SS) is crucial for normal vascular structure and function. As a result of anemia-related lower whole-blood viscosity (WBV), SS could be reduced in patients with ESRD and might be associated with arterial functional alterations. In 44 patients with ESRD and 25 control subjects, brachial artery (BA) compliance and BA diameter changes (flow-mediated dilation [FMD[) were evaluated in response to local shear rate and SS changes during hand warming-induced hyperemia. Patients with ESRD and control subjects had similar BA blood flow, but SS was lower in patients with ESRD (P < 0.001), with lower shear rate (P < 0.01) and lower WBV (P < 0.0001). In control subjects, SS was positively (and physiologically) correlated with arterial diameter (P < 0.001). In contrast, in patients with ESRD, larger arterial diameter was associated with low SS (P < 0.05) and increased arterial wall elastic modulus (P < 0.001). Anemia-associated low WBV aggravates low shear rate, further contributing to SS reduction. These abnormalities were associated with decreased vasodilating response to endothelial mechanical stimulation. Compared with control subjects, BA compliance and FMD increases in response to hand warming-induced increased SS were lower in ESRD patients (P < 0.01), whereas their BA diameter response to glyceryl trinitrate did not differ. The long-term WBV and SS increases after anemia correction improved FMD (P < 0.01) and BA compliance (P < 0.05) and heightened arterial wall sensitivity to mechanical stimulation. Maintenance low SS as a result of anemia could play an indirect role in arterial dysfunction in patients with ESRD.

Adult↗

PubMed2007

Mineral metabolism and arterial functions in end-stage renal disease: potential role of 25-hydroxyvitamin D deficiency.

In ESRD, arterial function is abnormal, characterized by decreased capacitive function (arterial stiffening) and reduced conduit function, shown by diminished flow-mediated dilation (FMD). The pathophysiology of these abnormalities is not clear, and this cross-sectional study analyzed possible relationships among arterial alterations and cardiovascular risk factors, including mineral metabolism parameters, such as serum parathormone, and vitamin D "nutritional" and "hormonal" status by measuring serum 25-hydroxyvitamin D [25(OH)D(3)] and 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] levels. Aortic stiffness (pulse wave velocity), brachial artery (BA) distensibility (echotracking; n = 42), BA FMD (hand-warming; n = 37), and arterial calcification scores (echography and plain x-rays) were measured in 52 stable and uncomplicated patients who were on hemodialysis. 25(OH)D(3) and 1,25(OH)(2)D(3) serum levels were low and weakly correlated (r = 0.365, P < 0.05). After adjustment for BP and age, multivariate analyses indicated that 25(OH)D(3) and 1,25(OH)(2)D(3) were negatively correlated with aortic pulse wave velocity (P < 0.001) and positively correlated with BA distensibility (P < 0.01) and FMD (P < 0.001). Arterial calcification scores were not independently associated with 25(OH)D(3) and 1,25(OH)(2)D(3) serum concentrations. These results suggest that nutritional vitamin D deficiency and low 1,25(OH)(2)D(3) could be associated with arteriosclerosis and endothelial dysfunction in patients who have ESRD and are on hemodialysis.

Adolescent↗

PubMed2006

Cardiovascular disease in the dialysis population: prognostic significance of arterial disorders.

PURPOSE OF REVIEW: Cardiovascular disease is a major factor in the high mortality of patients with end-stage renal disease, and this population is particularly appropriate to analyse the impact of cardiovascular risk markers on outcome. RECENT FINDINGS: Cardiovascular risk markers in end-stage renal disease include age, left ventricular mass, carotid intima-media thickness, blood pressure and aortic stiffness (pulse wave velocity). Aortic pulse wave velocity has been shown to be an independent predictor of cardiovascular mortality in patients with end-stage renal disease and the general population. Aortic pulse wave velocity has the highest sensitivity and specificity as a predictor of cardiovascular death in end-stage renal disease patients. Pulse wave velocity is an integrated index of vascular function and structure, and is a major determinant of systolic hypertension, thereby increasing left ventricular afterload, left ventricular hypertrophy and left ventricular oxygen consumption. Decreased diastolic blood pressure, another consequence of arterial stiffening, is associated with decreased coronary perfusion contributing to ischaemic heart disease and evolution of adaptive into maladaptive left ventricular hypertrophy. SUMMARY: Aortic stiffness measurements could serve as an important tool in identifying end-stage renal disease patients at higher risk of cardiovascular disease. The ability to identify these patients would lead to better risk stratification and earlier and more cost-effective preventive therapy.

Adult↗

PubMed2005

Circulating endothelial microparticles are associated with vascular dysfunction in patients with end-stage renal failure.

Endothelial dysfunction and arterial stiffness are major determinants of cardiovascular risk in patients with end-stage renal failure (ESRF). Microparticles are membrane fragments shed from damaged or activated cells. Because microparticles can affect endothelial cells, this study investigated the relationship between circulating microparticles and arterial dysfunction in patients with ESRF and identified the cellular origin of microparticles associated with these alterations. Flow cytometry analysis of platelet-free plasma from 44 patients with ESRF indicated that circulating levels of Annexin V+ microparticles were increased compared with 32 healthy subjects, as were levels of microparticles derived from endothelial cells (three-fold), platelets (16.5-fold), and erythrocytes (1.6-fold). However, when arterial function was evaluated noninvasively in patients with ESRF, only endothelial microparticle levels correlated highly with loss of flow-mediated dilation (r = -0.543; P = 0.004), increased aortic pulse wave velocity (r = 0.642, P < 0.0001), and increased common carotid artery augmentation index (r = 0.463, P = 0.0017), whereas platelet-derived, erythrocyte-derived, and Annexin V+ microparticle levels did not. In vitro, microparticles from patients with ESRF impaired endothelium-dependent relaxations and cyclic guanosine monophosphate generation, whereas microparticles from healthy subjects did not. Moreover, in vitro endothelial dysfunction correlated with endothelial-derived (r = 0.891; P = 0.003) but not platelet-derived microparticle concentrations. In fact, endothelial microparticles alone decreased endothelial nitric oxide release by 59 +/- 7% (P = 0.025). This study suggests that circulating microparticles of endothelial origin are tightly associated with endothelial dysfunction and arterial dysfunction in ESRF.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2005

Stiffness of capacitive and conduit arteries: prognostic significance for end-stage renal disease patients.

The aorta is the principal capacitive element of the arterial tree and its increased stiffness, determined by measurement of aortic pulse wave velocity (PWV), is a strong independent predictor of cardiovascular mortality in the general population and end-stage renal disease (ESRD) patients. Whether stiffness of ESRD patients' peripheral arteries has the same prognostic value has never been investigated. A cohort of 305 ESRD patients was followed for 70+/-49 months (mean+/-SD). Ninety-six deaths of cardiovascular origin occurred. At entry into the study, together with standard clinical and biochemical analyses, patients' aortic, brachial artery, and femorotibial PWV were determined. Based on Kaplan-Meier survival curve analyses and Cox proportional hazards analyses, adjusted for age, pulse pressure, and clinical data, aortic PWV was a significant and independent predictor of outcome. Neither brachial artery nor femotibial artery stiffness was able to predict cardiovascular outcome. Receiver operating characteristic curve analysis of aortic PWV indicated the cutoff value of 10.75 m/s, with 84% sensitivity, 73% specificity, 87% negative predictive value, and 72% positive predictive value. These results provide evidence that, in ESRD, increased stiffness of capacitive arteries, like the aorta, is an independent strong predictor of cardiovascular mortality, whereas stiffness of peripheral conduit arteries had no prognostic value.

Adult↗

PubMed2005

Role of arterial wall properties in the pathogenesis of systolic hypertension.

Recent prospective epidemiologic studies have directed attention to systolic blood pressure (SBP) as a better guide than diastolic blood pressure (DBP) to evaluate cardiovascular and all mortality, and recent data have underlined the importance of pulse pressure (PP) as an independent cardiovascular (CV) risk factors(5-7) in individuals more than 50 years of age. Furthermore, it has been shown that drug treatment of hypertension frequently results in adequate control of DBP, whereas control of SBP is achieved to a significantly smaller extent. Such studies have focused attention on the factors that determine the level of SBP and PP. Systolic blood pressure results from the interaction of three principal factors: 1) characteristics of left ventricular ejection (stroke volume); 2) cushioning (dampening) function of the large arteries (arterial stiffness); and 3) propagative and reflective properties of the arterial tree (intensity of wave reflections and timing of incident and reflected pressure waves). Considering the different mechanisms associated with increased SBP, individualized therapeutic approaches will require knowledge of the patient's unique profile of arterial stiffness and wave reflection characteristics.

Antihypertensive Agents↗

PubMed2005

Advanced oxidation protein products as risk factors for atherosclerotic cardiovascular events in nondiabetic predialysis patients.

BACKGROUND: Inflammation and oxidative stress are established risk factors for atherosclerosis, but whether they contribute to the accelerated atherogenesis associated with chronic kidney disease (CKD) remains to be assessed at the predialysis stage. METHODS: We prospectively examined the relationship between plasma levels of C-reactive protein (CRP), fibrinogen, and advanced oxidation protein products (AOPPs), as selected markers of inflammation and oxidative stress, and incident first occlusive atherosclerotic cardiovascular (CV) events (ASCVEs) in a single-center cohort of 80 uremic predialysis patients without diabetes with a creatinine clearance ranging from 20 to 40 mL/min/1.73 m2 . RESULTS: During follow-up (median, 7 years), 21 patients developed coronary, cerebral, or peripheral artery occlusive accidents, an incidence of 44/1,000 patient-years. Except for older age, their conventional risk factors did not differ compared with the 59 patients who remained free of such accidents. Conversely, plasma levels of CRP (4.3 +/- 2.7 versus 2.3 +/- 2 mg/L; P = 0.005), fibrinogen (5.6 +/- 1.4 versus 4.4 +/- 1.2 mg/L; P = 0.0009), and AOPPs (58 +/- 20 versus 42 +/- 14 micromol/L; P = 0.0002) were significantly greater at baseline, although serum creatinine levels did not differ between the 2 groups. By multivariate Cox regression analysis, age and CRP, fibrinogen, and AOPP levels were significant independent predictors of ASCVEs. Risk factor-adjusted hazard ratios were as follows: age, 1.13 (95% confidence interval, 1.04 to 1.22; P = 0.002); CRP level, 1.37 (95% confidence interval, 1.05 to 1.79; P = 0.02); fibrinogen level, 2.23 (95% confidence interval, 1.20 to 4.13; P = 0.011); and AOPP level, 1.68 (95% confidence interval, 1.12 to 2.51; P = 0.011). CONCLUSION: CRP, fibrinogen, and AOPP levels independently predict ASCVEs in patients with CKD in the predialysis phase and might directly contribute to the uremia-associated accelerated atherogenesis.

Arteriosclerosis↗

PubMed2005

Arteriosclerosis, vascular calcifications and cardiovascular disease in uremia.

PURPOSE OF REVIEW: Arterial calcification in chronic kidney disease (CKD) is associated with increased cardiovascular risk. The mechanisms responsible for arterial calcification include alterations of mineral metabolism and expression of mineral-regulating proteins. RECENT FINDINGS: Arterial calcification is similar to bone formation, involving differentiation of vascular smooth muscle cells (VSMCs) into phenotypically distinct osteoblast-like cells. Elevated phosphate and/or calcium trigger a concentration-dependent increase of calcium precipitates in VSMC in vitro. The calcification is initiated by VSMC release of membrane-bound matrix vesicles and formation of apoptotic bodies. The presence of serum prevents these changes, indicating the presence of calcification inhibitors. Arterial calcification occurs in two sites: the tunica intima and tunica media. Intimal calcification is a marker of atherosclerotic disease and is associated with arterial stenotic lesions. Medial calcification influences outcome by promoting arterial stiffening whose principal consequences are left-ventricular hypertrophy and altered coronary perfusion. Aortic stiffness is an independent predictor of all-cause and cardiovascular mortality in CKD patients. Age, duration of dialysis, smoking and diabetes are risk factors for the development of arterial calcification in end-stage renal disease. Oversuppression of parathyroid hormone and low bone turnover potentiate the development of arterial calcification. SUMMARY: Arterial disease in CKD patients is characterized by extensive calcification. Evidence has accumulated pointing to the active and regulated nature of the calcification process. Elevated phosphate and calcium may stimulate sodium-dependent phosphate cotransport involving osteoblast-like changes in cellular gene expression. Arterial calcification is responsible for stiffening of the arteries with increased left-ventricular afterload and abnormal coronary perfusion as the principal clinical consequences.

Animals↗

PubMed2005

Modeling the implications of changes in vascular calcification in patients on hemodialysis.

BACKGROUND: The Treat-to-Goal Study found that sevelamer slowed the progression of coronary calcification in patients on hemodialysis compared to calcium-based phosphate binders. To understand the implications of this effect for cardiovascular events, risk equations are needed. METHODS: Data on 179 patients on hemodialysis treated at one center in France included biochemical values during the year prior to study entry, patient characteristics, and cardiovascular events over an average of 4 years. As arterial calcification was evaluated ultrasonographically and quantified using a 0 to 4 score, an equation relating this to the electron-beam tomography (EBT)-based calcification score used in the trial was developed and applied to all patients. The estimated scores were then used in survival and Cox proportional hazards analyses of cardiovascular events in relation to the degree of calcification, controlling for other characteristics. RESULTS: Mean age at inclusion was 54 years, dialysis vintage 70 months, average follow-up 49 months; 32% suffered an event. The calcification score, diabetes, C-reactive protein (CRP), diastolic blood pressure, gender, smoking and hypertension are independent predictors of cardiovascular risk. The resulting equation indicates that, relative to a calcification score below 400, the risk of an initial event increases 44% for a score of 600, and more than doubles for a score of 1000. CONCLUSION: In the absence of long-term follow-up studies, these equations permit quantification of the expected long-term clinical consequences of the impact of various phosphate binders on vascular calcification. Together with resource use and cost information, these equations are key inputs for formal cost-effectiveness analyses.

Blood Pressure↗

PubMed2004

Arterial stiffness and kidney function.

The vascular hallmark of subjects with end-stage renal disease undergoing hemodialysis is increased aortic stiffness, a phenomenon independent of mean arterial blood pressure, wall stress, and standard cardiovascular risk factors such as plasma glucose, cholesterol, obesity, and smoking. These observations suggest that subtle links might associate arterial stiffness and kidney function in normotensive and hypertensive populations. Recently, aortic pulse wave velocity and creatinine clearance have been shown to be statistically associated in subjects with plasma creatinine < or =130 micromol/L, again independently of mean arterial blood pressure and classical cardiovascular risk factors. This association was even shown to predominate in subjects younger than age 55 years. In addition, acceleration of aortic pulse wave velocity with age was more important in these subjects than in untreated normotensive control individuals, and the phenomenon was consistently predicted by baseline plasma creatinine values. Among all antihypertensive drugs, angiotensin-converting enzyme inhibitors only were shown to exhibit a significant and independent effect on aortic stiffness. The use of these drugs was significantly associated with improvement of large aortic stiffness in subjects treated for hypertension. In conclusion, increased stiffness of central arteries is independently associated with reduced creatinine clearance in subjects with mild to severe renal insufficiency, indicating that kidney diseases may interact not only with small but also with large conduit arteries, independently of age, blood pressure level, and classical cardiovascular risk factors. Whether sodium, divalent ionic species (calcium, phosphates), and the renin-angiotensin-aldosterone system play a role in such alterations remains to be elucidated.

Adult↗

PubMed2004

Mechanism(s) of selective systolic blood pressure reduction after a low-dose combination of perindopril/indapamide in hypertensive subjects: comparison with atenolol.

OBJECTIVES: The goal of this study was to determine if a low-dose combination of the angiotensin-converting enzyme inhibitor perindopril (Per) and the diuretic indapamide (Ind) reduces central (thoracic aorta, carotid artery) as well as brachial systolic blood pressure (SBP) more than the beta-blocker atenolol and to determine the hemodynamic factors influencing independently brachial and central SBP: pulse wave velocity (PWV) and pattern of wave reflections. BACKGROUND: In high cardiovascular risk populations, angiotensin blockade improves survival without affecting brachial SBP and diastolic blood pressure (DBP). Whether central SBP, which is physiologically lower than brachial SBP, is significantly reduced has never been investigated. METHODS: This study was a double-blind randomized trial for one year in patients with essential hypertension. RESULTS: For a similar DBP reduction, Per/Ind decreased SBP significantly more than atenolol, with a more pronounced reduction for central than for brachial SBP. After one year, the difference between brachial and central SBP was maintained by Per/Ind (8.28 +/- 1.53 mm Hg) and significantly attenuated by atenolol (0.29 +/- 1.61 mm Hg). Under atenolol, the principal factor modulating SBP reduction was mean blood pressure. Under Per/Ind, this parameter played a minor role, and the central SBP reduction implied a major role for disturbed PWV and wave reflections. CONCLUSIONS: Under Per/Ind, but not atenolol, normalization of brachial SBP is achieved with a significantly greater reduction of central SBP. This hemodynamic profile reflects changes of wave reflections issued from distal arterial and arteriolar territory, where Per/Ind, but not atenolol, is known to improve vessel wall structure.

Antihypertensive Agents↗

PubMed2004

Arterial stiffness and function in end-stage renal disease.

Cardiovascular disease is a major cause of mortality in patients with end-stage renal disease, with damage to arteries as a major contributing factor. Arterial stiffness is a factor associated with high systolic and pulse pressure in these patients and is a strong independent factor associated with morbidity and mortality. Arterial stiffness is one of the principal factors opposing left ventricular ejection. The appropriate term to define the arterial factor(s) opposing left ventricular ejection is aortic input impedance. Aortic input impedance depends on TPR, arterial distensibility, and wave reflections. Distensibility defines the capacitive properties of arterial stiffness, whose role it is to dampen pressure and flow oscillations and to transform pulsatile flow and pressure in arteries into a steady flow and pressure in peripheral tissues. Stiffness is the reciprocal value of distensibility. These parameters are blood pressure dependent; arteries become stiffer at high pressure. While distensibility provides information about the elasticity of the artery as a hollow structure, the elastic incremental modulus characterizes the properties of the arterial wall biomaterials independent of vessel geometry. Alternatively, arterial distensibility can be evaluated by measuring pulse wave velocity, which increases with the stiffening of arteries. Arterial stiffening increases left ventricular afterload and alters the coronary perfusion. With increased pulse wave velocity, the wave reflections affects the aorta during systole, which increases systolic pressures and myocardial oxygen consumption and decreases diastolic blood pressure and coronary flow. The arterial stiffness is altered primarily in association with increased collagen content and alterations of extracellular matrix and calcification of the arterial wall. The arterial stiffening estimated by changes in aortic pulse wave velocity and intensity of wave reflections are independent predictors of survival in end-stage renal disease and in the general population. Improvement of arterial stiffening could be obtained by antihypertensive treatments as observed with calcium-channel blockers and angiotensin-converting enzyme inhibitors. Angiotensin-converting enzymes inhibitors increase AC and reduce wave reflections. It has been shown that reversibility of aortic stiffening and use of angiotensin-converting enzyme inhibitors had a favorable independent effect on survival in hypertensive patients with advanced renal disease.

Aorta↗

PubMed2004

Arterial calcifications and bone histomorphometry in end-stage renal disease.

Arterial calcification (AC) is a common complication of end-stage renal disease (ESRD). The mechanisms responsible are complex, including disturbances of mineral metabolism and active expression of various mineral-regulating proteins. An inverse relationship between AC and bone density has been documented in uremic patients. In the study presented here, which included 58 patients with ESRD on hemodialysis (HD), bone-histomorphometry characteristics were compared with the AC scores (0 to 4) determined according to the number of arterial sites with calcifications. Patients with AC scores of 0 (no calcifications), or 1 or 2 (mild calcifications) had similar serum parathyroid hormone levels and bone histomorphometry, with larger osteoclast resorption, higher osteoclast numbers, and larger osteoblastic and double tertracycline-labeled surfaces. In contrast, patients with high AC scores (3 and 4) were characterized by lower serum parathyroid hormone, low osteoclast numbers and osteoblastic surfaces, smaller or absent double tetracycline-labeled surfaces, and high percentages of aluminum-stained surfaces. According to multivariate analysis, AC score was positively associated with age (P < 0.0001), daily dose of calcium-containing phosphate binders (P = 0.009), and bone aluminum-stained surfaces (P = 0.037), and an inverse correlation was observed with osteoblastic surfaces (P = 0.001). A high AC score is associated with bone histomorphometry suggestive of low bone activity and adynamic bone disease. These findings suggest that therapeutic interventions associated with excessive lowering of parathyroid activity (parathyroidectomy, excessive calcium or aluminum load) favor lower bone turnover and adynamic bone disease, which could influence the development and progression of AC.

Aluminum↗

PubMed2004

Selective reduction of cardiac mass and central blood pressure on low-dose combination perindopril/indapamide in hypertensive subjects.

OBJECTIVE: In hypertension, blockade of the renin-angiotensin system reduces left ventricular mass (LVM) independently of brachial systolic (S), diastolic (D), and mean (M) blood pressure (BP). From central to peripheral arteries, MBP and DBP are practically unchanged, whereas SBP and pulse pressure (PP) increase significantly. The objective was to determine whether changes in LVM under drug treatment was preferentially associated with changes in central or brachial SBP and PP. DESIGN: A substudy of 146 subjects was selected from 469 hypertensive patients submitted to a double-blind randomized trial comparing the combination of perindopril (2 mg; Per) and indapamide (0.625 mg; Ind) with atenolol (50 mg, one tablet per day). MAIN OUTCOME MEASURES: Before and after 1 year of treatment: LVM (echocardiography) in 146 subjects and, in 52 of them, central (carotid) BP and timing of wave reflections (tonometry). RESULTS: LVM changes were significantly associated with antihypertensive treatment, with lower LVM with Per/Ind than with atenolol. Changes in SBP and PP, but not in MBP and DBP, were more significantly associated with Per/Ind than with atenolol, with more pronounced effects using central than brachial measurements, and a longer delay in central return of wave reflections under Per/Ind. In the sampling of 52 patients with tonometry, the change in LVM between the two drug regimens was significantly linked to central, but not brachial, PP change. CONCLUSIONS: This observational study shows a lower LVM under Per/Ind than under atenolol. The greater change in LVM on Per/Ind was linked to central and not brachial blood pressure.

Adult↗

PubMed2004

Forearm reactive hyperemia and mortality in end-stage renal disease.

BACKGROUND: Reports on the general population indicated that decreased endothelial-mediated vasodilation has a prognostic impact on cardiovascular (CV) morbidity and mortality. Flow-dependent vasodilation of conduit arteries and ischemia-induced forearm reactive hyperemia are impaired in end-stage renal disease (ESRD). Whether deterioration of vasodilator function in ESRD patients has a prognostic impact has not been documented. The aim of this study was to determine whether the impaired forearm postischemic vasodilation is an independent predictor of mortality in ESRD patients, independently from CV end-organ damages, which are usually associated with decreased vasodilatory response. METHODS: Common carotid artery intima-media thickness (CCA-IMT), aortic stiffness (pulse wave velocity-PWV), and LV mass (LVM) were determined for 78 stable ESRD patients on hemodialysis. Forearm postischemic vasodilation [flow debt repayment (FDR)] was measured by venous plethysmography. All-cause mortality served as the outcome variable over a median follow-up of 60 +/- 27 months. RESULTS: Twenty-four deaths occurred (16 of CV origin). According to Cox regression adjusted for age, CCA-IMT, LVM, and PWV, all-cause mortality was independently associated with decreased FDR (RR 0.69 for every 10% increase; 95% CI 0.56-0.85; P= 0.0006) and increased aortic PWV (RR 1.16 for 1 m/s increase; 95% CI 1.04-1.29; P= 0.0091). CONCLUSION: Our data indicate that lower postischemic forearm reactive hyperemia is associated with all-cause mortality of ESRD patients, independently of the presence of end-organ damage such as LVH or arteriosclerosis.

Adolescent↗

PubMed2004

Early prediction of IgA nephropathy progression: proteinuria and AOPP are strong prognostic markers.

BACKGROUND: Inflammation and oxidative stress have been incriminated in the pathogenesis of IgA nephropathy (IgAN). The aim of the present study was to assess whether markers reflecting these pathophysiologic processes, namely C-reactive protein (CRP) and advanced oxidation protein products (AOPP), would allow-in conjunction with clinical and histopathologic parameters-to predict disease progression. METHODS: Between 1994 and 1997, 120 adult patients with biopsy-proven IgAN were included in a prospective cohort study, and followed until the end of 2002 or start of dialysis. In every patient, we determined plasma levels of CRP and AOPP. These parameters were included, together with clinical data, in a multivariate Cox proportional hazard regression analysis, with halving of baseline creatinine clearance as the primary renal end point. RESULTS: A total of 51 patients reached the renal end point, including 30 who had to start dialysis. With multivariate analysis, the most potent independent risk factors of poor renal outcome were proteinuria > or =1 g/day [proportional hazard risk (HR) = 23.7, P= 0.0001], hypertension (HR = 8.13, P= 0.008), and AOPP plasma level (HR = 1.09 per 10 micromol/L, P= 0.042), whereas angiotensin II inhibitors were protective (HR = 0.19, P= 0.001). CONCLUSION: Our data support the role of oxidative stress in the pathogenesis of IgAN and suggest that patients with proteinuria > or =1 g/day should be eligible for early implemented antioxidant and/or anti-inflammatory therapeutic strategies, with AOPP plasma level as a surrogate marker to evaluate their effects.

Adult↗

PubMed2003

Aortic pulse wave velocity index and mortality in end-stage renal disease.

BACKGROUND: Aortic pulse wave velocity (PWV) is a strong independent predictor of overall and cardiovascular mortality in patients with end-stage renal disease (ESRD). Nevertheless, because age, blood pressure, heart rate, and gender are strong determinants of both arterial stiffness and mortality, the individual relevance of PWV measurements remains controversial. METHODS: A cohort of 242 patients with ESRD undergoing hemodialysis was studied for a mean (+/- SD) duration of 78 +/- 46 months. At entry, together with standard clinical and biochemical analyses, PWV was measured using Doppler ultrasonography. On the basis of a nomogram established on 469 nonuremic subjects, a theoretical value of PWV was determined in ESRD patients according to their age, blood pressure, gender, and heart period. The PWV index (measured PWV - theoretical PWV) was then calculated for each individual ESRD patient. RESULTS: Based on Cox analysis, the PWV index, but neither pulse pressure nor cardiac mass, was a strong and independent predictor of both cardiovascular and overall mortality, together with age and time on dialysis before inclusion. Patients with positive (versus negative) PWV index had a twofold adjusted risk of mortality during the follow-up. Per each 1 meter/second PWV index increment, we observed a 34% (crude) and a 14% (adjusted) increase in both cardiovascular and overall mortality (P < 0.02 for all). CONCLUSION: In ESRD patients, the calculation of a PWV index provides information about cardiovascular and overall mortality risk with high predictive power, showing that PWV measurements provide discriminatory prognostic power over and above conventional cardiovascular risk factors.

Adult↗

PubMed2003

Inflammation, arteriosclerosis, and cardiovascular therapy in hemodialysis patients.

BACKGROUND: Aortic stiffness and left ventricular hypertrophy (LVH) are predictors of mortality in hemodialysis (HD) patients. Attenuation of arterial stiffness and regression of LVH had a favorable effect on survival in these patients, but this favorable effect was observed in less than 50% of patients, the rest being resistant to therapeutical interventions. The aim of this study was to analyze the factors associated with this resistance to treatment. METHODS: 138 patients on HD were studied during a follow-up survey. From entry until the end of follow up, the changes of aortic pulse wave velocity (PWV) and of LV mass were measured in response to treatment with antihypertensive drugs and erythropoietin, together with measurements of blood chemistry, including high-sensitive C-reactive protein (CRP). Patients with decreased aortic PWV were considered to be responders (N = 68), the others to be nonresponders (N = 70). RESULTS: Nonresponders were older (P < 0.05) and had persistently higher systolic blood pressure (BP) and pulse pressure. Responders were treated more frequently with an ACE inhibitor (P < 0.001), and had lower serum CRP (P < 0.01). The baseline PWV, as well as the changes of PWV and LV mass during the follow-up were significantly and independently correlated with serum CRP level (P < 0.001). According to logistic regression after adjustment for age, gender, diabetes, history of CVD, and the nonspecific cardiovascular risk factors, the improvement of aortic stiffness and LV hypertrophy was positively associated with prescription of ACE inhibitor (P < 0.0001), and negatively with the serum CRP level (P < 0.01). CONCLUSION: These results indicate that in HD patients, the presence of low-grade inflammation decreases the efficiency of cardiovascular therapeutic interventions and participates in the persistence of cardiovascular hemodynamic overload.

Adult↗