Estimated Glomerular Filtration Rate and Urinary Albumin Excretion Are Independently Associated with Greater Arterial Stiffness: The Hoorn Study
Marc M.H. Hermans*,,
Ronald Henry*,
Jacqueline M. Dekker,
Jeroen P. Kooman*,,
Piet J. Kostense,
Giel Nijpels,
Robert J. Heine and
Coen D.A. Stehouwer,
* Department of Internal Medicine; Division of Nephrology, Academic Hospital Maastricht, Maastricht; Institute for Research in Extramural Medicine, Vrÿe Universiteit University Medical Center; and Department of Clinical Epidemiology and Biostatistics, Vrÿre Universiteit, Amsterdam, Netherlands
Address correspondence to: Dr. Marc M.H. Hermans, Department of Internal Medicine, Division of Nephrology, Academic Hospital Maastricht, PO Box 5800, 6202 AZ Maastricht, Netherlands. Phone: +31-43-3875007; Fax: +31-43-3876281; mherm{at}sint.azm.nl
Received for publication November 8, 2006.
Accepted for publication March 15, 2007.
Mild renal insufficiency is a risk factor for cardiovasculardisease (CVD). Both a decline in GFR and (micro)albuminuriaare associated with greater cardiovascular mortality. In ESRD,arterial stiffness, an important cause of CVD, is known to begreater, but few data exist in individuals with mild renal insufficiencyor microalbuminuria. This study investigated the associationof impaired renal function expressed as lower GFR or greaterurinary albumin excretion with arterial stiffness. In a population-basedstudy in 806 individuals (402 men), mean age 68 yr (range 50to 87), peripheral arterial stiffness (by compliance and distensibilityof the carotid, brachial, and femoral arteries and by the carotidelastic modulus [Einc]) and central arterial stiffness (by totalsystemic arterial compliance, carotid-femoral transit time,and aortic augmentation index) were measured ultrasonically.GFR was estimated (eGFR) by the Modification of Diet in RenalDisease (MDRD) formula. Urinary albumin excretion was expressedas urinary albumin/creatinine ratio (UACR). eGFR was 60.6 ±11.1 ml/min per 1.73 m2. Median UACR was 0.57 mg/mmol (range0.1 to 26.6). After adjustment for age, mean arterial pressure(MAP), gender, and glucose tolerance status (GTS), each 5-ml/minper 1.73 m2 lower eGFR was associated with a lower distensibilitycoefficient of the carotid (regression coefficient 0.20103/kPa; 95% confidence interval [CI] 0.34 to0.07 103/kPa) and brachial artery (0.15103/kPa; 95% CI 0.28 to 0.03 103/kPa)and a greater carotid Einc (0.02 kPa; 95% CI 0.0004 to 0.04kPa). No statistically significant association was found ofeGFR with other arterial stiffness indices. After adjustmentfor age, MAP, gender, and GTS, a greater UACR (per quartile)was associated with a greater Einc (0.03 kPa; 95% CI 0.001 to0.07 kPa) and a trend to a lower distensibility coefficient(0.24 103/kPa; 95% CI 0.49 to 0.02 103/kPa)of the carotid artery. After adjustment for age, MAP, gender,and GTS, a greater UACR (per quartile) was in addition associatedwith a shorter carotid-femoral transit time (1.67 ms;95% CI 3.24 to 0.10 ms). These associations werenot substantially changed by mutual adjustment for eGFR andUACR. In individuals with mild renal insufficiency, both a lowereGFR and a greater albumin excretion, even below levels thatare considered to reflect microalbuminuria, are independentlyassociated with greater arterial stiffness. Moreover, theseassociations were mutually independent. These findings may explain,in part, why eGFR and microalbuminuria are associated with greaterrisk for CVD and suggest that amelioration of arterial stiffnesscould be a target of intervention.
Chronic kidney disease (CKD) is defined as a lowering of theGFR and/or the presence of (micro)albuminuria (1). In severeCKD (ESRD), cardiovascular mortality is greatly increased (2).Mild renal insufficiency has also been associated with a greatercardiovascular mortality (3,4). In addition, (micro)albuminuriahas been associated with an increase in cardiovascular disease(CVD) and mortality in a wide variety of populations (57).The underlying mechanisms are incompletely understood. Increasedarterial stiffness is a widely known process in severe CKD (810)and has been associated with greater cardiovascular mortality(11,12).
We hypothesized that arterial stiffness may be increased inmild renal insufficiency (stages 2 to 3 CKD [1]) and in individualswith (micro)albuminuria and that this may be one of the mechanismsthat link these conditions to CVD. To test this hypothesis,we investigated, in a population-based study of 806 individuals,the association between GFR (estimated by the Modification ofDiet in Renal Disease [MDRD] formula [13]) and arterial stiffness.In addition, we investigated the association between urinaryalbumin excretion (UAE) and arterial stiffness and whether theseassociations were mutually independent.
Study Population
For this cross-sectional investigation, we used data from the2000 Hoorn Study follow-up examination and the Hoorn ScreeningStudy. Details have been described elsewhere (14,15). Briefly,the Hoorn Study is a cohort study of glucose tolerance and CVDin the general population. The Hoorn Screening Study is a population-basedtargeted type 2 diabetes screening study. The local ethics committeeapproved the studies, and written informed consent was obtainedfrom all participants. Each participant underwent an oral glucosetolerance test, except those with previously diagnosed diabetes,and glucose tolerance status (GTS) was classified accordingto the 1999 World Health Organization criteria (16). The finalstudy population consisted of 806 individuals (299 with normalglucose metabolism, 181 with impaired glucose metabolism, and326 with type 2 diabetes).
Estimates of Renal Function
Renal function was estimated by the MDRD formula in ml/min per1.73 m2: 170 x creatinine0.999 x age0.176 x urea0.170x albumin0.318 x 0.762 if female (all participants where white).Because of missing laboratory values, estimated GFR (eGFR) couldnot be determined in 31 cases. Urinary albumin-creatinine ratio(UACR) in mg/mmol was determined in an overnight first-voidedurine sample. Microalbuminuria was defined as a UACR between2 and 30 mg/mmol. Urinary albumin was measured by rate nephelometry(Array Protein System; Beckman Coulter, Fullerton, CA) withan assay threshold of 2 mg/L. Urinary and serum creatinine wasmeasured by a modified Jaffé test. Patients with macroalbuminuria(>30 mg/mmol; n = 8) were excluded from further analysis.To include patients (n = 86) with an albuminuria level belowthe assay threshold, a UACR was calculated with albumin concentrationset at 1.9 mg/L divided by the urinary creatinine concentration.Formulas are given in traditional units. To convert to InternationalSystem units, multiply creatinine in mg/dl by 88.4, urea inmg/dl by 0.357, and albumin in g/dl by 10.
BP Measurement
Brachial artery (BA) systolic (SBP) and diastolic BP (DBP) wereassessed in the left upper arm at 5-min intervals with an oscillometricdevice (Colin Press-Mate BP-8800, Colin Medical Instruments,San Antonio, TX), as described previously (17). Brachial pulsepressure (PP) was calculated as systolic minus DBP and brachialmean arterial pressure (MAP) as (2 x DBP + SBP)/3. PP at thecarotid (CCA) and femoral artery (FA) was calculated accordingto the calibration method described by Kelly and Fitchett (18),with use of distension waveforms as adapted from Van Bortelet al. (19). This method assumes a constant difference betweenMAP and DBP along the arterial tree. PP can be calculated ata target artery (PPtar) from the PP at a reference artery (PPref)and a calibration factor (K) at target and reference arteries(Ktar and Kref) by the formula PPtar = PPref x Ktar/Kref, inwhich K is defined as (MAP DBP)/PP, and (MAP DBP) can be calculated from the area under the pressure curvedivided by time (18,19).
Arterial Properties Diameter, Distension, and Intima-Media Thickness.
Details have been described elsewhere (17). Briefly, a singleobserver who was unaware of the participants clinicalor glucose tolerance status obtained properties of the rightCCA, FA, and BA, with the use of an ultrasound scanner (350Series, 7.5-MHz probe; Pie Medical, Maastricht, The Netherlands).The scanner was connected to a PC equipped with vessel wallmovement detection software (Wall Track System; Pie Medical).Data were obtained from three consecutive measurements. Diastolicdiameter was calculated as the difference between the anteriorand posterior wall markers. The change of diameter as a functionof time (distension) was estimated and presented on the computerscreen (distension waveform). In addition, the carotid posteriorwall thickness was calculated. The mean diameter, distension,and intima-media thickness (IMT) were used in analysis.
Peripheral Arterial Stiffness: Distensibility, Compliance, and Youngs Elastic Modulus.
We calculated CCA, BA, and FA distensibility and compliancecoefficients as follows (20):
Distensibility coefficient = (2D x D + D2)/(P x D2) in 103/kPa
Compliance coefficient = (2D x D + D2)/(4 x P) in mm2/kPa
where D is distension, D is diameter, and P is PP.
The distensibility coefficient reflects the elastic properties,whereas the compliance coefficient reflects the buffering capacity.From IMT, diameter, and carotid distensibility, we calculatedYoungs elastic modulus (Einc), an indicator of the intrinsicwall properties:
Einc = diameter/(IMT x distensibility coefficient) in kPa
Central Arterial Stiffness: Carotid-Femoral Transit Time, Aortic Augmentation Index, and Total Systemic Arterial Compliance.
Carotid-femoral transit time (CFTT), which is a measure of aortic(thoracic-abdominal) compliance, was measured as described elsewhere(17,21). Briefly, CFTT is the travel time of a pressure wavefrom the CCA to the FA, and it is an approximation of the pulsewave velocity (PWV) (22). We determined the CFTT by continuousmeasurement of the diameter (distension curves) of the rightCCA and FA. We then determined the average time delay (meanof three recordings) from the electrocardiograph trigger to10% of the ascending slope of the distension curve of both arteriesand subtracted the carotid value from the femoral value to obtainthe CFTT. We did not measure the carotid-femoral distance noninvasivelybecause this might induce error in obese and older patients(tortuous aorta). Instead of measuring the carotid-femoral distance,we adjusted for height in statistical analysis. Reproducibilityof the CFTT has been reported (23).
The aortic augmentation index (aAIX) represents the additionalload to which the left ventricle is subjected as a result ofthe timing of wave reflection. In addition, the aAIX dependson the heart rate amplitude and location of the reflection sitesand is a less pure estimate of arterial stiffness (24). We usedradial applanation tonometry performed with a Millar piezoresistivepressure transducer connected to an arterial wave form analysisdevice (Sphygmocor, Moreton-in-the-Marsh, UK) (25) to obtainthe aAIX and aortic PP. The aAIX was calculated as augmentedpressure divided by (tonometrically derived) central PP.
Total systemic arterial compliance (ml/mmHg) was determinedaccording to the ratio of stroke volume to aortic PP (26). Thismethod used the ratio of stroke volume to aortic PP (ml/mmHg)to determine total systemic arterial compliance, for which strokevolume was calculated as cardiac output divided by heart rate,and aortic PP was calculated by use of a calibration method(vide supra). This method multiplies the difficulty in accuratelydetermining stroke volume and PP at the ascending aorta noninvasively(27), which means that these data should be interpreted withcaution.
Reproducibility.
Reproducibility of the aforementioned methods have been reported(17,25).
Statistical Analyses
All analyses were carried out with SPSS. Multiple linear regressionanalysis was used to investigate the associations between renalfunction estimates and arterial properties. All associationswere first analyzed without adjustments and then with adjustmentsfor potential confounders. Because the population was stratifiedaccording to age, gender, and GTS and arterial stiffness isaffected by age, gender, GTS, and MAP (20,28), these variableswere considered first in the adjusted models. We used brachialMAP for all adjustments because MAP is constant throughout thearterial tree (19). Diabetes is often accompanied with impairedrenal function and arterial stiffness. Interaction terms wereused to investigate whether the association between eGFR andUAE with arterial stiffness differed according to the presenceof diabetes. Two sided P < 0.05 was considered statisticallysignificant.
Of the 806 participants, eGFR was missing in 31 cases and UACRin five cases. Seven patients were excluded because of macroalbuminuria(albuminuria >30 mg/mmol). The associations between eGFRand arterial stiffness were studied in the remaining 767 individuals,and the association between UACR and arterial stiffness wasstudied in 794 individuals. Qualitatively satisfactory examinationswere obtained of 756 CCA, 689 BA, and 656 FA. The main reasonfor missing data was poor definition of the arterial wall attributableto obesity. Except for body mass index (BMI) the nonparticipantswere comparable with the study population.
Baseline Characteristics Tables 1 and 2 show the characteristics of the study populationaccording to tertiles of eGFR and according to quartiles ofUACR, respectively. eGFR ranged from 24 to 114 ml/min per 1.73m2. Most individuals (n = 755) had mild to moderate CKD (stages2 to 3). Three participants had severe (stage 4) CKD, and ninehad stage 1 CKD (eGFR 90 ml/min per 1.73 m2 with microalbuminuria).Median UACR was 0.57 mg/mmol (range 0.1 to 26.6 mg/mmol).
Table 2. Baseline characteristics of the study population according to quartiles of UACRa
Arterial Properties According to eGFR
For the CCA, BA, and FA, a lower eGFR was associated with greaterarterial diameter, PP, and carotid IMT, whereas associationswith distension were NS. As a result, a lower eGFR was associatedwith lower distensibility coefficients and a greater carotidEinc, whereas associations with the compliance coefficientswere NS (Table 3). Lower eGFR was not associated with centralarterial stiffness.
Table 3. Arterial wall properties according to tertiles of eGFRa
After adjustment for age, MAP, gender, and GTS, a lower eGFRwas inversely associated with CCA, BA, and FA distensibility(P = 0.002, P = 0.03, and P = 0.07, respectively) and carotidcompliance (P = 0.09) and directly with carotid Einc (P = 0.04).These associations were not affected by further adjustment forUACR. The association with carotid Youngs elastic wasNS after additional adjustment for BMI (Table 4).
Table 4. CCA, BA, and FA stiffness indices according to eGFR: Adjusted analysesa
Table 5 shows that the association between a lower eGFR andgreater arterial stiffness of BA and FA was driven by associationswith greater arterial diameter. The association with greatercarotid Einc was driven by a smaller distension of the CCA.
Table 5. Associations of eGFR and arterial wall properties: Adjusted analysesa
Arterial Properties According to UAE Expressed as UACR
For the CCA, BA, and FA, a greater UACR was associated witha greater CCA and BA and a smaller FA diameter, with less CCAand FA and more BA distension, with greater PP in all threearteries, and with greater carotid IMT. As a result, a greaterUACR was associated with less CCA and FA distensibility andcompliance and with a greater carotid Einc (Table 6).
Table 6. Arterial wall properties according to quartiles of the UACRa
After adjustment for age, gender, GTS, and MAP, a greater UACRwas associated with less CCA distensibility (P = 0.07) and withgreater Einc (P = 0.04; Table 7). Further adjustment for eGFR,the presence of hypertension, or previous CVD slightly strengthenedthe associations with CCA distensibility and Einc (Table 7).Table 8 shows that the associations between UACR and CCA distensibilityand Einc were driven mainly by the association with CCA diameter.
Table 8. Associations of UACR (in quartiles) and arterial wall properties: Adjusted analysesa
With regard to central arterial stiffness indices, a greaterUACR was associated with a lower CFTT and total systemic arterialcompliance and an increase in the aAIX (Table 6). After adjustmentfor age, gender, GTS, and MAP, associations between UACR andmeasures of central arterial stiffness were not statisticallysignificant except for the association between UACR and CFTT.Age and MAP seemed to be the strongest confounders. Furtheradjustments for eGFR, hypertension, and previous CVD slightlyweakened the association between UACR and CFTT (Table 9).
Table 9. Associations of UACR (in quartiles) and measures of central arterial stiffness: Adjusted analysesa
Additional Analyses
The results did not change materially after additional adjustmentsfor total cholesterol, triglycerides, HDL cholesterol, and LDLcholesterol; use of lipid-lowering or anti-hypertensive drugs;or current smoking. With regard to the eGFR analyses, resultsalso did not change after adjustment for previous CVD, diagnosisof hypertension, or waist-to-hip ratio. With regard to the UACRanalyses, results did not change after additional adjustmentfor BMI or waist-to-hip ratio (data not shown). Exclusion ofindividuals with stage 1 (n = 9) and stage 4 CKD (n = 3) didnot materially change the results. Furthermore, endothelialdysfunction is known to be related to arterial stiffness andto mortality in renal insufficiency (29,30); therefore, analyseswere also adjusted for flow-mediated endothelium-dependent vasodilationof the BA. Also these adjustments did not materially changethe results. Interaction analyses showed that the associationbetween eGFR and UAE with arterial stiffness was not substantiallyinfluenced by the presence of diabetes.
This population-based study had four main findings. First, inmild renal insufficiency (stages 2 to 3 CKD), a lower eGFR asestimated by the MDRD formula was associated with greater arterialstiffness. Second, a greater UAE, even below levels that areconsidered to indicate microalbuminuria, was associated withgreater arterial stiffness. Third, lower eGFR and greater UAEwere mutually independently associated with a greater arterialstiffness, suggesting that the mechanisms that link these variablesto risk for CVD are at least in part independent of each other.Fourth, in contrast to a greater UAE, eGFR was not related togreater central arterial stiffness.
Our results with respect to the association of eGFR with arterialstiffness are partially in line with previous studies. Koningset al. (31) showed, in a small study, that the distensibilitycoefficient of the CCA was lower in patients with stages 2 to4 CKD compared with control subjects. In contrast to our study,Mourad et al. (32) showed, in a population with mild renal insufficiency,a negative association between creatinine clearance and carotid-femoralPWV. Wang et al. (33) recently showed a greater aortic PWV inpatients with stages 1 to 5 CKD. We, in agreement with a recentlypublished study by Briet et al. (34), did not find an associationof CFTT, an approximation of the PWV, with eGFR. Also in agreementwith that study was our finding of an independent, negativerelationship between eGFR and carotid Einc.
In general, with declining renal function, the distensibilityof the arteries decreased, whereas the compliance coefficientremained largely unchanged. To a large extent, this phenomenonwas explained by a greater arterial diameter in individualswith lower eGFR, which, for the BA and FA, was independent ofMAP. It is not clear why there was no relation between eGFRand CCA diameter. In fact, Briet et al. (34) recently foundan inverse relation between GFR and CCA internal diameter. Thediscrepancy with our results may be related to selective mortalityin the Hoorn Study, because we previously showed that both agreater CCA diameter (35) and a lower eGFR (3,29) are relatedto increased mortality. A greater CCA diameter is thought toreflect so-called outward remodeling (36) and may be a defensemechanism to prevent loss of buffering capacity in case of adecrease in distensibility. The causes of a decrease in distensibilityin mild renal insufficiency remain largely unclear. In animalmodels, renal insufficiency is associated with an accumulationof collagen instead of elastin in the aortic wall (37), andcollagen represents the more rigid component of the arterialwall (10). Changes in water and salt balance (38), leading torenin-angiotensin-aldosterone system activation, may stimulatethe collagen accumulation (39). Also other factors such as theaccumulation of advanced glycosylation end products; the accumulationof asymmetric dimethylarginine, an endogenous inhibitor of nitricoxide synthesis; and oxidative stress may negatively influencethe distensibility of the arterial wall (40,41).
We showed that greater UAE, even in a low-grade albuminuricrange, was associated with a greater diameter and Einc of theCCA and a lower CFTT. In patients with type 1 diabetes, severalauthors have shown an association between microalbuminuria andgreater CCA stiffness (42,43). Recently, Yokohama et al. (44)found in patients with type 2 diabetes that albuminuria wasindependently associated with carotid IMT. This was in linewith the finding of Keech et al. (45), who showed in patientswith type 2 diabetes that a greater UAE in the low-albuminuricrange was independently associated with greater carotid IMT.However, in agreement with Kramer et al. (46), we did not findan association, either in the group as a whole or in the individualswith diabetes (n = 318) separately (data not shown). Our findingof an association between arterial stiffness and albumin excretionbelow the current microalbuminuria level is in agreement withstudies that showed that the association between UAE and CVDstarts at levels below microalbuminuria (7,47). Endothelialdysfunction and low-grade inflammation may be important mechanismsthat link UAE with arterial stiffness and CVD (29,30), but itremains to be shown whether the association of UAE and arterialstiffness actually explains that between UAE and CVD.
The third major finding of our study was the mutual independenceof the associations of eGFR and albuminuria with arterial stiffness.This suggests that both a decline in GFR and albuminuria, althoughthey might share determinants such as hypertension and diabetes,could be independently associated with CVD in patients withCKD. Indeed, we recently showed that the association of eGFRwith cardiovascular mortality is mostly independent of UAE (29).
A final finding of our study was that eGFR and UAE differedin their association with central arterial stiffness. Whereasboth a lower eGFR and greater albuminuria were associated witha decrease in peripheral arterial stiffness, only greater albuminuriawas associated with a lower CFTT (Figure 1). As stated in theforegoing, in individuals with mild to moderate renal insufficiency,conflicting results exist regarding the relation of eGFR withcarotid-femoral PWV (3234). In agreement with our results,in patients with type 2 diabetes (48) and in hypertensive patients(49), microalbuminuria has been associated with a greater carotid-femoralPWV. Again, one of the links between UAE and central arterialstiffness could be endothelial dysfunction and low-grade inflammation(50). However, also after adjustment for BA endothelial flow-mediateddilation, the associations between UAE and PWV remained largelyunchanged. It is not clear why this relation is not seen betweeneGFR and central arterial stiffness.
Figure 1. Means of distensibility coefficient of carotid artery (103/kPa; A) and carotid-femoral transit time (ms; B) according to estimated GFR (eGFR; in tertiles) and urinary albumin creatinine ratio (UACR; in quartiles). *P < 0.05 for trend.
The potential clinical impact of our findings can be appreciatedfrom the following comparisons. The aortic PWV is an independentpredictor of cardiovascular morbidity and mortality, and all-causemortality (27). The change in CFTT (%), an approximation ofthe PWV, per quartile of UACR was approximately 3%, which wasassociated with an increase of CVD risk of 18% in the RotterdamStudy (51) and an increase of all-cause mortality risk of 3%(52). Although only aortic and carotid stiffness have shownto be of predictive value for CVD in CKD populations (27), dataon FA stiffness are also of potential clinical importance. Atleast in patients with type 2 diabetes, FA stiffness is a predictorof peripheral vascular disease (53,54). To the best of our knowledge,no data exist on the relation between FA stiffness and peripheralvascular disease in patients with CKD.
This study had several limitations. First, the study populationwas relatively old. This might have caused underestimation ofthe relation between eGFR or UAE and arterial stiffness. A "healthysurvivor effect" may also have weakened the associations ofeGFR or UAE with IMT. Second, our data were cross-sectionaland do not provide insight into the mechanisms that are responsiblefor the observed associations. Third, we studied a white population,and it remains to be established whether the results can begeneralized to other ethnicities.
In this population-based study, we showed that stages 2 to 3CKD was associated with peripheral but not central arterialstiffness. We also showed that UAE, even below levels that conventionallyare considered to define microalbuminuria, was associated withgreater CCA stiffness and a decrease in CFTT. This finding questionsthe current arbitrary cutoff point for microalbuminuria. Furthermore,our findings suggest that in patients with CKD, both GFR andalbuminuria should be interpreted as independent risk factorsfor CVD.
Our data underscore the importance of adequate treatment ofpatients with mild renal impairment with or without albuminuria.At present, angiotensin-converting enzyme inhibitors and angiotensinreceptor blockers may have the best data on preventing a declinein renal function (55) and diminishing albuminuria (56). Mostrecently, in a hypertensive population, the combination of acalcium antagonist and an angiotensin-converting enzyme inhibitorresulted in a greater lowering of central aortic pressure anda better cardiovascular outcome compared with a strategy thatconsisted of a blocker plus a diuretic (57). Most important,however, is a greater awareness of the importance of mild renalimpairment and albuminuria for cardiovascular risk.
K/DOQI clinical practice guidelines for chronic kidney disease: Evaluation, classification, and stratification.
Am J Kidney Dis 39
: S1
S266, 2002[CrossRef][Medline]
Foley RN, Parfrey PS, Sarnak MJ: Epidemiology of cardiovascular disease in chronic renal disease.
J Am Soc Nephrol 9[Suppl]
: S16
S23, 1998[CrossRef][Medline]
Henry RM, Kostense PJ, Bos G, Dekker JM, Nijpels G, Heine RJ, Bouter LM, Stehouwer CD: Mild renal insufficiency is associated with increased cardiovascular mortality: The Hoorn Study.
Kidney Int 62
: 1402
1407, 2002[CrossRef][Medline]
De Leeuw PW, Thijs L, Birkenhager WH, Voyaki SM, Efstratopoulos AD, Fagard RH, Leonetti G, Nachev C, Petrie JC, Rodicio JL, Rosenfeld JJ, Sarti C, Staessen JA: Prognostic significance of renal function in elderly patients with isolated systolic hypertension: Results from the Syst-Eur trial.
J Am Soc Nephrol 13
: 2213
2222, 2002[Abstract/Free Full Text]
Stehouwer CD, Nauta JJ, Zeldenrust GC, Hackeng WH, Donker AJ, den Ottolander GJ: Urinary albumin excretion, cardiovascular disease, and endothelial dysfunction in non-insulin-dependent diabetes mellitus.
Lancet 340
: 319
323, 1992[CrossRef][Medline]
Hillege HL, Fidler V, Diercks GF, van Gilst WH, de Zeeuw D, van Veldhuisen DJ, Gans RO, Janssen WM, Grobbee DE, de Jong PE: Urinary albumin excretion predicts cardiovascular and noncardiovascular mortality in general population.
Circulation 106
: 1777
1782, 2002[Abstract/Free Full Text]
Arnlov J, Evans JC, Meigs JB, Wang TJ, Fox CS, Levy D, Benjamin EJ, DAgostino RB, Vasan RS: Low-grade albuminuria and incidence of cardiovascular disease events in nonhypertensive and nondiabetic individuals: The Framingham Heart Study.
Circulation 112
: 969
975, 2005[Abstract/Free Full Text]
London GM: Alterations of arterial function in end-stage renal disease.
Nephron 84
: 111
118, 2000[CrossRef][Medline]
Guerin AP, London GM, Marchais SJ, Metivier F: Arterial stiffening and vascular calcifications in end-stage renal disease.
Nephrol Dial Transplant 15
: 1014
1021, 2000[Abstract/Free Full Text]
Safar ME, London GM, Plante GE: Arterial stiffness and kidney function.
Hypertension 43
: 163
168, 2004[Abstract/Free Full Text]
Guerin AP, Blacher J, Pannier B, Marchais SJ, Safar ME, London GM: Impact of aortic stiffness attenuation on survival of patients in end-stage renal failure.
Circulation 103
: 987
992, 2001[Abstract/Free Full Text]
Blacher J, Safar ME, Guerin AP, Pannier B, Marchais SJ, London GM: Aortic pulse wave velocity index and mortality in end-stage renal disease.
Kidney Int 63
: 1852
1860, 2003[CrossRef][Medline]
Levey AS, Bosch JP, Lewis JB, Greene T, Rogers N, Roth D: A more accurate method to estimate glomerular filtration rate from serum creatinine: A new prediction equation. Modification of Diet in Renal Disease Study Group.
Ann Intern Med 130
: 461
470, 1999[Abstract/Free Full Text]
Mooy JM, Grootenhuis PA, de Vries H, Valkenburg HA, Bouter LM, Kostense PJ, Heine RJ: Prevalence and determinants of glucose intolerance in a Dutch Caucasian population. The Hoorn Study.
Diabetes Care 18
: 1270
1273, 1995[Abstract]
Spijkerman AM, Adriaanse MC, Dekker JM, Nijpels G, Stehouwer CD, Bouter LM, Heine RJ: Diabetic patients detected by population-based stepwise screening already have a diabetic cardiovascular risk profile.
Diabetes Care 25
: 1784
1789, 2002[Abstract/Free Full Text]
Alberti KG, Zimmet PZ: Definition, diagnosis and classification of diabetes mellitus and its complications. Part 1: Diagnosis and classification of diabetes mellitus provisional report of a WHO consultation.
Diabet Med 15
: 539
553, 1998[CrossRef][Medline]
Henry RM, Kostense PJ, Spijkerman AM, Dekker JM, Nijpels G, Heine RJ, Kamp O, Westerhof N, Bouter LM, Stehouwer CD: Arterial stiffness increases with deteriorating glucose tolerance status: The Hoorn Study.
Circulation 107
: 2089
2095, 2003[Abstract/Free Full Text]
Kelly R, Fitchett D: Noninvasive determination of aortic input impedance and external left ventricular power output: A validation and repeatability study of a new technique.
J Am Coll Cardiol 20
: 952
963, 1992[Abstract]
Van Bortel LM, Balkestein EJ, van der Heijden-Spek JJ, Vanmolkot FH, Staessen JA, Kragten JA, Vredeveld JW, Safar ME, Struijker Boudier HA, Hoeks AP: Non-invasive assessment of local arterial pulse pressure: Comparison of applanation tonometry and echo-tracking.
J Hypertens 19
: 1037
1044, 2001[CrossRef][Medline]
ORourke MF, Staessen JA, Vlachopoulos C, Duprez D, Plante GE: Clinical applications of arterial stiffness; definitions and reference values.
Am J Hypertens 15
: 426
444, 2002[CrossRef][Medline]
Schram MT, Henry RM, van Dijk RA, Kostense PJ, Dekker JM, Nijpels G, Heine RJ, Bouter LM, Westerhof N, Stehouwer CD: Increased central artery stiffness in impaired glucose metabolism and type 2 diabetes: The Hoorn Study.
Hypertension 43
: 176
181, 2004[Abstract/Free Full Text]
Nichols WW, ORourke MF: Properties of the arterial wall. In:
McDonalds Blood Flow in Arteries, 4th Ed., London, Arnold, 1998
, pp 54
72
van Dijk RA, van Ittersum FJ, Westerhof N, van Dongen EM, Kamp O, Stehouwer CD: Determinants of brachial artery mean 24 h pulse pressure in individuals with type II diabetes mellitus and untreated mild hypertension.
Clin Sci (Lond) 102
: 177
186, 2002[Medline]
Davies JI, Struthers AD: Pulse wave analysis and pulse wave velocity: A critical review of their strengths and weaknesses.
J Hypertens 21
: 463
472, 2003[CrossRef][Medline]
Pannier BM, Avolio AP, Hoeks A, Mancia G, Takazawa K: Methods and devices for measuring arterial compliance in humans.
Am J Hypertens 15
: 743
753, 2002[CrossRef][Medline]
Chemla D, Hebert JL, Coirault C, Zamani K, Suard I, Colin P, Lecarpentier Y: Total arterial compliance estimated by stroke volume-to-aortic pulse pressure ratio in humans.
Am J Physiol 274
: H500
H505, 1998[Medline]
Laurent S, Cockcroft J, Van Bortel L, Boutouyrie P, Giannattasio C, Hayoz D, Pannier B, Vlachopoulos C, Wilkinson I, Struijker-Boudier H: Expert consensus document on arterial stiffness: Methodological issues and clinical applications.
Eur Heart J 27
: 2588
2605, 2006[Abstract/Free Full Text]
De Angelis L, Millasseau SC, Smith A, Viberti G, Jones RH, Ritter JM, Chowienczyk PJ: Sex differences in age-related stiffening of the aorta in subjects with type 2 diabetes.
Hypertension 44
: 67
71, 2004[Abstract/Free Full Text]
Stam F, van Guldener C, Becker A, Dekker JM, Heine RJ, Bouter LM, Stehouwer CD: Endothelial dysfunction contributes to renal function-associated cardiovascular mortality in a population with mild renal insufficiency: The Hoorn study.
J Am Soc Nephrol 17
: 537
545, 2006[Abstract/Free Full Text]
Amabile N, Guerin AP, Leroyer A, Mallat Z, Nguyen C, Boddaert J, London GM, Tedgui A, Boulanger CM: Circulating endothelial microparticles are associated with vascular dysfunction in patients with end-stage renal failure.
J Am Soc Nephrol 16
: 3381
3388, 2005[Abstract/Free Full Text]
Konings CJ, Dammers R, Rensma PL, Kooman JP, Hoeks AP, Kornet L, Gladziwa U, van der Sande FM, Leunissen KM: Arterial wall properties in patients with renal failure.
Am J Kidney Dis 39
: 1206
1212, 2002[CrossRef][Medline]
Mourad JJ, Pannier B, Blacher J, Rudnichi A, Benetos A, London GM, Safar ME: Creatinine clearance, pulse wave velocity, carotid compliance and essential hypertension.
Kidney Int 59
: 1834
1841, 2001[CrossRef][Medline]
Wang MC, Tsai WC, Chen JY, Huang JJ: Stepwise increase in arterial stiffness corresponding with the stages of chronic kidney disease.
Am J Kidney Dis 45
: 494
501, 2005[CrossRef][Medline]
Briet M, Bozec E, Laurent S, Fassot C, London GM, Jacquot C, Froissart M, Houillier P, Boutouyrie P: Arterial stiffness and enlargement in mild-to-moderate chronic kidney disease.
Kidney Int 69
: 350
357, 2006[CrossRef][Medline]
van Dijk RA, Dekker JM, Nijpels G, Heine RJ, Bouter LM, Stehouwer CD: Brachial artery pulse pressure and common carotid artery diameter: Mutually independent associations with mortality in subjects with a recent history of impaired glucose tolerance.
Eur J Clin Invest 31
: 756
763, 2001[CrossRef][Medline]
Amann K, Neususs R, Ritz E, Irzyniec T, Wiest G, Mall G: Changes of vascular architecture independent of blood pressure in experimental uremia.
Am J Hypertens 8
: 409
417, 1995[CrossRef][Medline]
Safar ME, Thuilliez C, Richard V, Benetos A: Pressure-independent contribution of sodium to large artery structure and function in hypertension.
Cardiovasc Res 46
: 269
276, 2000[Abstract/Free Full Text]
Blacher J, Amah G, Girerd X, Kheder A, Ben Mais H, London GM, Safar ME: Association between increased plasma levels of aldosterone and decreased systemic arterial compliance in subjects with essential hypertension.
Am J Hypertens 10
: 1326
1334, 1997[Medline]
London GM, Guerin AP, Pannier B, Marchais SJ, Safar ME: Large artery structure and function in hypertension and end-stage renal disease.
J Hypertens 16
: 1931
1938, 1998[CrossRef][Medline]
London GM, Guerin AP, Marchais SJ, Pannier B, Safar ME, Day M, Metivier F: Cardiac and arterial interactions in end-stage renal disease.
Kidney Int 50
: 600
608, 1996[Medline]
Lambert J, Smulders RA, Aarsen M, Donker AJ, Stehouwer CD: Carotid artery stiffness is increased in microalbuminuric IDDM patients.
Diabetes Care 21
: 99
103, 1998[Abstract]
Giannattasio C, Failla M, Piperno A, Grappiolo A, Gamba P, Paleari F, Mancia G: Early impairment of large artery structure and function in type I diabetes mellitus.
Diabetologia 42
: 987
994, 1999[CrossRef][Medline]
Yokoyama H, Aoki T, Imahori M, Kuramitsu M: Subclinical atherosclerosis is increased in type 2 diabetic patients with microalbuminuria evaluated by intima-media thickness and pulse wave velocity.
Kidney Int 66
: 448
454, 2004[CrossRef][Medline]
Keech AC, Grieve SM, Patel A, Griffiths K, Skilton M, Watts GF, Marwick TH, Groshens M, Celermajer DS: Urinary albumin levels in the normal range determine arterial wall thickness in adults with type 2 diabetes: A FIELD substudy.
Diabet Med 22
: 1558
1565, 2005[CrossRef][Medline]
Kramer H, Jacobs DR Jr, Bild D, Post W, Saad MF, Detrano R, Tracy R, Cooper R, Liu K: Urine albumin excretion and subclinical cardiovascular disease. The Multi-Ethnic Study of Atherosclerosis.
Hypertension 46
: 38
43, 2005[Abstract/Free Full Text]
Gerstein HC, Mann JF, Yi Q, Zinman B, Dinneen SF, Hoogwerf B, Halle JP, Young J, Rashkow A, Joyce C, Nawaz S, Yusuf S: Albuminuria and risk of cardiovascular events, death, and heart failure in diabetic and nondiabetic individuals.
JAMA 286
: 421
426, 2001[Abstract/Free Full Text]
Smith A, Karalliedde J, De Angelis L, Goldsmith D, Viberti G: Aortic pulse wave velocity and albuminuria in patients with type 2 diabetes.
J Am Soc Nephrol 16
: 1069
1075, 2005[Abstract/Free Full Text]
Mule G, Cottone S, Vadala A, Volpe V, Mezzatesta G, Mongiovi R, Piazza G, Nardi E, Andronico G, Cerasola G: Relationship between albumin excretion rate and aortic stiffness in untreated essential hypertensive patients.
J Intern Med 256
: 22
29, 2004[CrossRef][Medline]
Kinlay S, Creager MA, Fukumoto M, Hikita H, Fang JC, Selwyn AP, Ganz P: Endothelium-derived nitric oxide regulates arterial elasticity in human arteries in vivo.
Hypertension 38
: 1049
1053, 2001[Abstract/Free Full Text]
Mattace-Raso FU, van der Cammen TJ, Hofman A, van Popele NM, Bos ML, Schalekamp MA, Asmar R, Reneman RS, Hoeks AP, Breteler MM, Witteman JC: Arterial stiffness and risk of coronary heart disease and stroke: The Rotterdam Study.
Circulation 113
: 657
663, 2006[Abstract/Free Full Text]
Willum-Hansen T, Staessen JA, Torp-Pedersen C, Rasmussen S, Thijs L, Ibsen H, Jeppesen J: Prognostic value of aortic pulse wave velocity as index of arterial stiffness in the general population.
Circulation 113
: 664
670, 2006[Abstract/Free Full Text]
Kizu A, Koyama H, Tanaka S, Maeno T, Komatsu M, Fukumoto S, Emoto M, Shoji T, Inaba M, Shioi A, Miki T, Nishizawa Y: Arterial wall stiffness is associated with peripheral circulation in patients with type 2 diabetes.
Atherosclerosis 170
: 87
91, 2003[CrossRef][Medline]
Taniwaki H, Shoji T, Emoto M, Kawagishi T, Ishimura E, Inaba M, Okuno Y, Nishizawa Y: Femoral artery wall thickness and stiffness in evaluation of peripheral vascular disease in type 2 diabetes mellitus.
Atherosclerosis 158
: 207
214, 2001[CrossRef][Medline]
Ruggenenti P: Angiotensin-converting enzyme inhibition and angiotensin II antagonism in nondiabetic chronic nephropathies.
Semin Nephrol 24
: 158
167, 2004[CrossRef][Medline]
Williams B, Lacy PS, Thom SM, Cruickshank K, Stanton A, Collier D, Hughes AD, Thurston H, ORourke M: Differential impact of blood pressure-lowering drugs on central aortic pressure and clinical outcomes: Principal results of the Conduit Artery Function Evaluation (CAFE) study.
Circulation 113
: 1213
1225, 2006[Abstract/Free Full Text]