Asymmetrical dimethylarginine is associatedwith renal and cardiovascular outcomes andall-cause mortality in renal transplant recipientsSadollah Abedini1,9, Andreas Meinitzer2,9, Ingar Holme3, Winfried Marz4, Gisela Weihrauch5,Bengt Fellstrøm6, Alan Jardine7 and Hallvard Holdaas8

1Department of Medicine, Renal Section, Toensberg County Hospital, Toensberg, Norway; 2Clinical Institute of Medical andChemical Laboratory Diagnostics, Graz, Austria; 3Department of Preventive Medicine and Centre of Clinical Research, Oslo UniversityHospital Ullevaal, Oslo, Norway; 4Synlab for Medizinisches Versorgungzentrum fur Labordiagnostik Heidelberg, Heidelberg, Germany;5Clinical Institute of Medical and Chemical Laboratory Diagnosis, Medical University of Graz, Graz, Austria; 6Department of MedicalScience, Renal Unit, University Hospital, Uppsala, Sweden; 7Department of Medicine and Therapeutics, Western Infirmary Hospital,Glasgow, United Kingdom and 8Department of Medicine, Oslo University Hospital Rikshospitalet, Oslo, Norway

Increased plasma levels of asymmetric dimethylarginine

(ADMA) are associated with endothelial dysfunction and

predict the progression to dialysis and death in patients

with chronic kidney disease. The effects of these increased

ADMA levels in renal transplant recipients, however, are

unknown. We used the data from ALERT, a randomized,

double-blind, placebo-controlled study of the effect of

fluvastatin on cardiovascular and renal outcomes in 2102

renal transplant recipients with stable graft function on

enrollment. Patients who were initially randomized to

fluvastatin or placebo in the 5- to 6-year trial were offered

open-label fluvastatin in a 2-year extension of the original

study. After adjustment for baseline values for established

factors in this post hoc analysis, ADMA was found to be

a significant risk factor for graft failure or doubling of

serum creatinine (hazard ratio 2.78), major cardiac events

(hazard ratio 2.61), cerebrovascular events (hazard ratio 6.63),

and all-cause mortality (hazard ratio 4.87). In this trial

extension, the number of end points increased with

increasing quartiles of plasma ADMA levels. All end points

were significantly increased in the fourth compared to the

first quartile. Our study shows that elevated plasma levels

of ADMA are associated with increased morbidity, mortality,

and the deterioration of graft function in renal transplant

recipients.

Kidney International (2010) 77, 44–50; doi:10.1038/ki.2009.382;

published online 21 October 2009

KEYWORDS: asymmetric dimethylarginine (ADMA); cardiovascular events;

death; fluvastatin; renal graft failure; renal transplantation

Patient and graft survival after renal transplantation hasimproved considerably over the recent decades. Current5- and 10-year patient survival rates are around 85 and66%, and allograft half-lives have improved from 7.7 yearsin the mid 1980s to 10.9 years in mid 1990s.1 However, lifeexpectancy of renal transplant recipients is still shortenedand premature graft failure is a major clinical problem.

We have previously shown that atherogenic lipids are riskfactors for premature cardiac events in renal transplantrecipients, and that this risk is reduced by lipid-loweringtherapy.2,3 However, despite statin treatment, the risk ofmajor cardiac events (MACEs) in this population remainselevated. In addition to traditional cardiovascular (CV)risk factors, numerous modifiable, and non-modifiable riskfactors have been proposed to contribute to the excessiveCV risk in renal transplant recipients,4,5 and to the risk ofallograft failure.6 One potential risk factor is asymmetricdimethylarginine (ADMA), an established risk factor for CVevents and all-cause mortality in other populations,7 whichhas not been investigated in transplant recipients.

Asymmetric dimethylarginine has also been shown inpatients with chronic kidney disease (CKD) to be animportant risk factor for progression to end-stage renaldisease and all-cause mortality.8

Asymmetric dimethylarginine is an endogenous competitiveinhibitor of nitric oxide synthase and reduces nitric oxide (NO)generation,9,10 thus inhibiting the beneficial effect of NOon vasodilatation, arterial stiffness, and endothelial function.11,12

ADMA levels are inversely related to glomerular filtrationrate (GFR) in patients with mild-to-moderate CKD,8,13 andelevated levels have been associated with CV events and deathin patients receiving hemodialysis.14,15 Thus, ADMA may bea predictor for renal graft loss, CV events and all-cause mortalityin patients with different stages of CKD. The contribution ofADMA for such events in renal transplant recipients isunknown.

o r i g i n a l a r t i c l e http://www.kidney-international.org

& 2010 International Society of Nephrology

Received 10 May 2009; revised 12 July 2009; accepted 11 August 2009;

published online 21 October 2009

Correspondence: Sadollah Abedini, Department of Medicine, Renal Section,

Toensberg County Hospital, Pb 2168, 3103 Toensberg, Norway.

E-mail: sadollah.abedini@gmail.com

9These authors contributed equally to this work

44 Kidney International (2010) 77, 44–50

RESULTSBaseline characteristics

Basic patients and demographic data in Assessment of Lescolin Renal Transplantation (ALERT) and the extension ALERThave been published previously.2,16 Participants in the ALERTwere renal transplant recipients with stable graft function fora mean duration of 4.5 years before randomization into thetrail. The treatment arms in the ALERT study werecomparable with regard to baseline demographic and clinicalcharacteristic. There were no differences in ADMA valuesbetween placebo and fluvastatin arms. In this post hocanalysis, we separated the patients into ADMA quartilesaccording to ADMA levels. Estimated glomerular filtration(ml/min per 1.73 m2) was calculated by using the formulafrom the Modification of Diet in Renal Disease study.17 Thedemographic data are summarized in Table 1. Patients in thedifferent ADMA quartiles are comparable with regard to age,blood pressure, lipid levels, body mass index, and serumcalcium and phosphate values. There was a tendency toincreased serum creatinine and decreased estimated GFRwith higher ADMA levels, although ADMA was only weaklybut significantly correlated with serum creatinine (r¼ 0.218,P¼ 0.000) and as expected inversely correlated with esti-mated GFR (r¼�0.193, P¼ 0.000). Hypertension and use ofantihypertensive drugs was also more common in patientswith higher ADMA levels.

Outcomes

Incident rates for renal, cardiac, cerebrovascular (CBV)events and for all cause of death in each quartile of ADMAare summarized in Table 2. Differences between second andfourth ADMA quartiles versus first quartile were testedusing log-rank test. P-values are given versus first quartile.Kaplan–Meier curves for survivors in each quartile of ADMAare shown in Figure 1. Figure 2 shows relative risk for studyoutcomes within the asymmetric dimethylarginine (ADMA)quartiles compared with the first quartile.

Renal end points. The number of graft failure or doubling ofserum creatinine increased in higher ADMA quartiles,and was highly significant when the third and fourth quartilewas compared with the first quartile. The number of graft failureand doubling of serum creatinine almost doubled (79 (16.6%) to137 (29.8%), Po0.001) from the first to the fourth quartile.

Cardiac end points. The number of MACE and cardiacdeath or non-fatal myocardial infarction increased in higherADMA quartiles. These differences were statistically signifi-cant between the first and the fourth quartile.

Cerebrovascular events. Rate of CBV events increased withincreasing ADMA quartiles and the number of CBV eventswere more than doubled (3–4 to 11.0%) from the first to thefourth quartile.

All-cause mortality

Number of all cause of death increased also by ADMA quartilesand the number of events was almost doubled (13.9 to 26.8%)in the fourth quartile compared with the first quartile.

Risk factor analysis

The results from the Cox risk factor analyses are summarizedin Table 3. The hazard ratios (HR) with 95% confidenceintervals (95% CI) and corresponding P-values are shownfor all study outcomes. The univariate model includedcontinuous ADMA values and study outcomes as dependentvariable. The multivariate model was adjusted for potentiallyimportant baseline covariates such as age, gender, systolicblood pressure, previous CHD, diabetes mellitus, low-densitylipoprotein cholesterol, smoking, and estimated GFR.

In both univariate and multivariate analysis, ADMAis associated with all study end points. ADMA is anindependent predictor of GFDSC (graft failure and doublingof serum creatinine): HR 2.78 (95% CI: 1.22–5.82, P¼ 0.009),MACE: HR 2.61 (95% CI: 1.03–6.61, P¼ 0.042), cardiacdeath or non-fatal myocardial infarction: HR 4.90 (95% CI:1.70–14.10, P¼ 0.003), CBV events: HR 7.63 (95% CI:2.52–23.13, Po0.001), and all-cause death: HR 4.87(95% CI: 2.12–11.18, Po0.000).

DISCUSSION

This study is the first to report that plasma levels of ADMAare associated with increased incidence of MACE, cardiacdeath or non-fatal myocardial infarction, CBV events, all-cause mortality, and deterioration of graft function in renaltransplant recipients. Our findings in this population mirrorprevious reports in patient with non-transplanted patientswith or without CKD.18

Epidemiological studies have suggested associationbetween ADMA and hypertension,19 hypercholesterolemia,20

diabetes mellitus,21 and increased CV risk in CKD.7,9,22,23

Impaired endothelial function is thought to primarilyreflect decreased bioavailability of NO, and an endothelium-derived vasodilator with anti-atherosclerotic properties.24

In renal transplant recipients, endothelial dysfunction iswell documented, and leads to functional and structuralchanges that influence arterial stiffness.25,26 Arterial stiffness,assessed by pulse wave velocity, is present in renal transplantrecipients, and is enhanced by the use of calcineurininhibitors.27,28 Owing to the pre-existing endothelial dysfunc-tion, renal transplant recipients are at high risk for deleteriouseffect of inhibitors of NO, such as ADMA. There is noestablished therapy for elevated ADMA, although rosiglita-zone, amlodipine, and valsartan decrease ADMA level.28,29

Renal transplant recipients have numerous traditional andnon-traditional risk factors for CV events, and althoughdyslipidemia-dependent CV events, such as myocardialinfarction,2 are reduced by lipid-lowering therapy, there is aconsiderable residual risk for cardiac mortality and morbidityin these patients.

Although the procedure of renal transplantation maydecrease the raised level associated with hemodialysis, ADMAis still increased in renal transplant recipients compared withhealthy controls.30 A raised level of ADMA in our study wasassociated with a higher incidence of CV events. In the highestquartile of ADMA, the incidence was approximately doubled

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Table 1 | Patients’ demographic data in relation to ADMA quartiles in the extension ALERT

ADMA ADMA ADMA ADMA1. Q 2. Q 3. Q 4. Q

p0.69 0.70–0.77 0.78–0.85 X0.86N=476 N=462 N=450 N=459

Patients’ demographics (N=1847) Mean (s.d.) Mean (s.d.) Mean (s.d.) Mean (s.d.)Age at baseline (years) 47.3 (10.5) 49.8 (11.1) 50.3 (10.9) 51.5 (10.8)Systolic BP (mm Hg) 142.9 (18.3) 143.8 (18.8) 144.9 (19.4) 146.1 (18.7)Diastolic BP (mm Hg) 85.8 (9.2) 85.7 (9.65) 85.5 (10.1) 85.5 (10.2)Total cholesterol (mmol/l) 6.5 (1.2) 6.6 (1.1) 6.5 (1.1) 6.4 (1.1)HDL cholesterol (mmol/l) 1.4 (0.4) 1.3 (0.4) 1.3 (0.5) 1.3 (0.4)LDL cholesterol (mmol/l) 4.1 (1.0) 4.3 (1.0) 4.2 (1.0) 4.1 (1.0)Triglycerides (mmol/l) 2.2 (1.2) 2.2 (1.1) 2.2 (1.2) 2.3 (1.2)Apolipoprotein B (mg/dl) 116.8 (25.5) 116.3 (24.6) 115.3 (27.6) 116.3 (24.7)Body mass index (kg/m2) 25.5 (4.3) 25.0 (4.2) 25.7 (4.5) 25.9 (4.7)Serum creatinine (mmol/l) 133.9 (46.7) 135.7 (41.7) 145.6 (53.9) 163.0 (60.8)Estimated GFR 52.5 (17.2) 50.5 (14.3) 48.6 (16.0) 44.1 (15.9)hs-CRP (mg/l) 3.8 (7.0) 3.2 (5.4) 3.7 (6.7) 4.6 (7.7)Calcium (mmol/l) 2.4 (0.1) 2.4 (0.2) 2.4 (0.2) 2.4 (0.2)Phosphate (mg/dl) 3.5 (0.6) 3.6 (0.7) 3.5 (0.8) 3.7 (0.8)ADMA mmol/l 0.64 (0.04) 0.73 (0.02) 0.81 (0.02) 0.95 (0.10)

Transplant characteristicsTime on dialysis (month) 22.0 (37.0) 25 (39.1) 31.2 (47.4) 33.9 (46.0)Age at last Tx 41.8 (10.9) 44.7 (11.4) 45.4 (11.3) 46.5 (11.2)Donor age (years) 38.2 (15.4) 40.9 (15.0) 41.7 (15.2) 43.8 (15.2)Total time on RRT (years) 87.2 (56.1) 86.1 (56.0) 90.0 (60.1) 93.0 (59.1)Living-donor Tx N (%) 134 (28.2) 102 (22.2) 97 (21.6) 84 (18.3)Cold ischemia time (h) 19.9 (7.2) 19.6 (7.7) 19.4 (7.5) 19.9 (7.8)

Cardiovascular risk factors N (%) N (%) N (%) N (%)Diabetes mellitus 96 (20.2) 83 (18.0) 86 (19.2) 83 (18.1)Hypertension 331 (69.5) 336 (73.0) 343 (76.4) 361 (78.6)Left-ventricular hypertrophy 48 (10.1) 61 (13.3) 76 (16.9) 89 (19.4)Chronic heart disease 41 (8.6) 36 (7.8) 41 (9.1) 55 (12.0)Smoking: previous 180 (37.8) 156 (33.9) 156 (34.7) 158 (34.4)Smoking: current 64 (13.4) 88 (19.1) 90 (20.0) 105 (22.9)

Primary renal diseaseGlomerulonephritis 186 (39.1) 163 (35.4) 172 (38.3) 155 (33.8)PCKD 62 (13.0) 74 (16.1) 64 (14.3) 85 (18.5)Diabetic nephropathy 73 (15.3) 60 (13.0) 51 (11.4) 56 (12.2)Pyelo-interstitial nephritis 56 (11.8) 59 (12.8) 63 (14.0) 55 (12.0)Hypertension 20 (4.2) 30 (6.5) 19 (4.2) 19 (4.1)Vasculitis 2 (0.4) 6 (1.3) 6 (1.3) 4 (0.9)SLE 10 (2.1) 8 (1.7) 5 (1.1) 7 (1.5)Other case 62 (13.0) 47 (10.2) 52 (11.6) 71 (15.5)Unknown 22 (4.6) 24 (5.2) 29 (6.5) 23 (5.0)

Concomitant medicationb-Blockers 267 (56.1) 281 (61.1) 282 (62.8) 316 (68.8)Calcium antagonists 329 (69.1) 324 (70.4) 321 (71.5) 323 (70.4)ACE inhibitors or AT1-blockers 238 (50.0) 224 (48.7) 220 (49.0) 233 (50.8)Diuretics 213 (44.7) 245 (53.3) 260 (57.9) 315 (68.6)a-Blockers 70 (14.7) 69 (15.0) 77 (17.1) 100 (21.8)Nitrate 34 (7.1) 36 (7.8) 37 (8.2) 47 (10.2)ASA 148 (31.1) 163 (35.4) 168 (37.4) 175 (38.1)Cumarine/Warfarin 31 (6.5) 42 (9.1) 36 (8.0) 51 (11.1)Active D-vitamin 56 (11.8) 57 (12.4) 71 (15.8) 118 (25.7)

ImmunosuppressantsPrednisolone 368 (77.3) 385 (83.7) 382 (85.1) 377 (82.1)Cyclosporine A 467 (98.1) 451 (98.0) 442 (98.4) 446 (97.2)Azathioprine 333 (70.0) 323 (70.2) 284 (63.3) 269 (58.6)Mycophenolate mofetil 55 (11.6) 76 (16.5) 65 (14.5) 81 (17.6)

ACE, angiotensin-converting enzyme; ADMA, asymmetric dimethylarginine; ALERT, Assessment of Lescol in Renal Transplantation; ASA, acetyl salicylic acid; AT1, angiotensin IIreceptor blocker; BP, blood pressure; GFR, glomerular filtration rate; HDL, high-density lipoprotein; hsCRP, high sensitivity C-reactive protein; IL-6, interleukin-6; LDL, low-density lipoprotein; PCKD, polycystic kidney disease; PTH, parathyroid hormone; Q, quartile; RRT, renal replacement therapy; SLE, systemic lupus erythematosus; TX, renaltransplantation.

46 Kidney International (2010) 77, 44–50

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compared with that in the lowest quartile. In heart transplantpatients, elevated ADMA has been associated with coronaryintimal hyperplasia; treatment with sirolimus rather thanmycophenolate resulted in a significant decrease in ADMAlevels and reduced risk of cardiac allograft vasculopathy.31

The experience from the heart study and our study in renaltransplant recipients strongly favor an association betweenADMA levels and cardiac markers and cardiac end points.

Renal transplant recipients also have an increased risk fora CBV disease and, although the risk factors for ischemic

versus hemorrhagic stroke may vary, stroke occurrence isseveral times higher than the background population.32

A somewhat surprising finding in our study was that ADMAwas very strongly related to the occurrence of CBV events inthis population. In healthy individuals, suppressor doses ofADMA increases arterial stiffness and decreases cerebralblood flow, and ADMA thus may be involved in thepathogenesis of CBV disease.33 In several papers, stroke ispart of a composite CV end point, but is not reportedseparately.18,34 An association of stroke incidence and ADMAis therefore difficult to assess. To our knowledge, our study isthe first to show a strong association between ADMA levelsand stroke events.

In patients with CKD, the levels of ADMA are increasedcompared with those in patients with normal renal function.Elevated ADMA level in the circulation are a combined resultof impaired kidney function and a reduced activity ofthe enzymatic catabolism of ADMA by dimethylargininedimethylaminohydrolase.35 Plasma level of ADMA is elevatedin all types of patients with impaired renal function, withmaximal (sevenfold) elevation in patient with end-stage renaldisease treated by hemodialysis. About 60% of ADMA isremoved during a hemodialysis session.9,36,37

Numerous experimental study suggests that reduced NOactivity is involved in progressive kidney damage in patientswith CKD.38–42

After successful renal transplantation, ADMA is decreasedand is associated with an improvement in endothelialfunction, albeit without any effect on graft function.30 Innon-transplant patients with CKD Ravani et al.8 showed

Table 2 | Event rates for outcomes by ADMA quartiles

ADMA 1.Q ADMA 2.Q ADMA 3.Q ADMA 4.Qp69 0.70–0.77 0.78–0.85 0.86+

End points N=476 N=460 N=449 N=459

GFDSC N (%) 79 (16.6) 87 (18.9) 96 (21.4) 137 (29.8)P-value — 0.396 0.047 o0.001MACE N (%) 62 (13.0) 62 (13.5) 70 (15.6) 87 (18.9)P-value — 0.813 0.216 0.005CDNFMI N (%) 42 (8.8) 43 (9.3) 51 (11.4) 71 (15.5)P-Value — 0.760 0.172 0.001CBV events N (%) 22 (4.60) 45 (9.8) 55 (12.3) 52 (11.3)P-value — 0.003 o0.001 o0.001All causes of death N (%) 63 (13.9) 71 (15.4) 86 (19.2) 123 (26.9)P-value — 0.549 0.038 o0.001

ADMA, asymmetric dimethylarginine; CBV, cerebrovascular; CDNFMI, cardiac death ornon-fatal myocardial infarction; GFDSC, graft failure or doubling of serum creatinine;MACE, major adverse cardiovascular events; Q, quartile.Data expressed as number of patients in quartile/number of event (%). Significanceversus first quartile.

1.0

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0.00 2.00 4.00 6.00 8.0010.000.00 2.00 4.00 6.00 8.00 10.00

MACE GFDSC

DeathCBV events

1

1

2

2

2

4

3

112

4

3

3

34

4

Figure 1 | Kaplan-Meier curves for study end points byasymmetric dimethylarginine (ADMA) quartiles. (a) MACE,major cardiac events. (b) GFDSC, graft failure or doubling of serumcreatinine. (c) CBV events, cerebrovascular events. (d) All-causemortality. Numbers 1–4 denote ADMA quartiles 1–4. The x axisindicates follow-up time in years; the y axis indicates cumulativesurvival by ADMA quartile.

GFDSC MACE

*

* *

*

*

*

*

*

*

*

CDNFMI CBV Death2.5

2

1.5

1

0.5

01. Q 2. Q 3. Q 4. Q

Figure 2 | Relative risk for study outcomes within theasymmetric dimethylarginine (ADMA) quartiles comparedwith the first quartile. x axis, ADMA quartiles 1–4; y axis, relativerisk. CBV, cerebrovascular; CDNFMI, cardiac death or non-fatalmyocardial infarction; GFDSC, graft failure or doubling of serumcreatinine; MACE, major cardiac event. *Denotes significantdifference in relative risk compared with ADMA in first quartile,P-value o0.05. Q, quartile.

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that ADMA was a strong and independent risk marker forprogression to end-stage renal disease. There are numerousreports that ADMA is associated with progressive renaldysfunction and also with progression to end-stage renaldisease, but no publication has assessed ADMA as a potentialrisk factor for graft failure. In our study, ADMA was, afteradjustments for serum creatinine and proteinuria, inde-pendently associated with long-term deterioration of graftfunction in renal transplant patients.

Potential limitations of our study merit considerations.Although we have shown a strong association betweenADMA levels and clinical outcomes, the data do not implya causal relationship. Erythropoietin use was not registeredin our database. Erythropoietin might influence endothelialcell production of ADMA,43 however, that is not likely tobe a major concern in this stable cohort of renal transplantrecipients with a rather well-preserved renal function aftertransplantation. The patients in fourth quartile had morecomorbid conditions compared with patients in the firstquartile, and this was reflected in increased ADMA concen-trations. The strength of the study is the randomized controldesign, the long follow-up time and the independentadjudication of all clinical end points.

In conclusion, this is the first study to report that ADMAlevels are associated with deterioration of graft function,cardiac death and non-fatal myocardial infarction, CBVevents, and mortality in renal transplant recipients. Increasedlevels of ADMA might explain some of the excess CVmorbidity and mortality, and should be target for futureinvestigations in this population. ADMA levels may be usedin risk stratification and identification of renal transplantrecipients at high risk of CV disease and graft loss, and maybe modifiable by treatment. Clinical trials to assess thepotential of therapeutic reductions in ADMA level on CVand renal end points will be eagerly awaited in thispopulation, as ADMA might be associated with adverseoutcomes.

MATERIALS AND METHODSStudy design

The ALERT study design and baseline data have been describedpreviously.16 Briefly, ALERT was a randomized, double-blind,

placebo-controlled study of the effect of fluvastatin, 40–80 mgdaily, on cardiac and renal outcomes in 2102 renal transplantrecipients over a follow-up period of 5–6 years. Eligible patientswere men and women aged 30–75 years, who had received arenal transplant more than 6 months earlier and had a serumtotal cholesterol concentration between 4.0 and 9.0 mmol/l(155–348 mg/dl). Patients were excluded if they were on statintherapy, had familial hypercholesterolemia, or had experiencedan acute rejection episode in the 3 months before randomiza-tion. In addition, patients with a predicted life expectancyof less than 1 year were excluded. Of 1787 patients whocompleted ALERT, 1652 (92%) were offered open-labelfluvastatin 80 mg/dag in a 2-year extension to the originalstudy. Mean total follow-up time in the extension studywas 6.7 years.3 The study adhered to the InternationalConference on Harmonization guidelines for Good ClinicalPractice and is in accordance with the Declaration of HelsinkiPrinciples. All participants provided written informed consent,and the ethics committee at each participating center approvedthe trial.

Outcome definitions

Renal end point was the time to GFDSC. Cardiac end pointwas MACE and was defined as cardiac death, non-fatalmyocardial infarction, or coronary intervention procedure.CBV event was defined as any CBV event, including fataland non-fatal stroke. All end points were validated by anindependent clinical end point committee blinded to studydrug allocation.2,16

Laboratory

Inclusion laboratory values of the ALERT trial are reportedpreviously.16 ADMA levels were measured in blood samplesobtained at inclusion in 1847 patients.16 ADMA wasmeasured in frozen serum (�801C) with reversed-phasedHPLC (high-performance liquid chromatography).44

Statistical analysis

In the initial analysis, the treatment and placebo arms wereanalyzed separately for clinical events. As the two armsshowed no significant heterogeneity in relationships betweenADMA as a risk factor and event outcome, subsequent

Table 3 | Hazard ratios for ADMA by univariate and multivariate Cox proportional hazard models in 1847 renal transplantrecipients

Extension ALERT study (placebo+fluvastatin)

Study end points HR (95% CI) univariate P-value HR (95 % CI) multivariate P-value

GFDSC 10.50 (5.34–20.66) o0.001 2.78 (1.22–5.82) 0.009MACE 4.41 (1.92–10.14) o0.001 2.61 (1.03–6.61) 0.042CDNFMI 7.32 (2.88–18.65) o0.001 4.90 (1.70–14.10) 0.003Cerebrovascular events 10.32 (3.79–28.07) o0.001 7.63 (2.52–23.13) o0.000All-cause death 9.25 (4.50–19.00) o0.001 4.87 (2.12–11.18) o0.000

ADMA, asymmetric dimethylarginine; CBV, cerebrovascular events; CDNFMI, cardiac death or non-fatal myocardial infarction; GFDSC, graft failure or doubling of serumcreatinine; MACE, major adverse cardiovascular events.Hazard ratios were adjusted for clinically important covariates as age, gender, systolic blood pressure, previous CHD, diabetes mellitus, LDL-cholesterol, smoking, and serumcreatinine in the multivariate Cox model.

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analysis was performed on the pooled patient population.SPSS version 16.0 (2008 SPSS, Chicago, USA) was used forstatistical analysis. For normally distributed variables, meanand s.d. are presented. Demographic and clinical baselinecharacteristics were compared using independent samplest-test and w2-test for continuous and categorical variables,respectively. A Cox proportional hazard model was used toanalyze the relationship between risk factors and time toevent for all end points. All covariates were carefullyexamined and fulfilled the assumptions of proportionalityof HR in the Cox hazard models. Univariate and multivariateanalysis were then carried out to determine the association ofADMA with cardiac and renal events (GFDSC, major adversecardiac events (MACE—myocardial infarction, cardiac death,and coronary interventions), cardiac death and non-fatalmyocardial infarction, all-cause mortality, and CBV events).Corresponding HR for group comparisons were calculatedwith 95% confidence limits.

DISCLOSURENovartis Pharma supported the ALERT core (Lancet 2003;36: 2024-31)and the extension study (AJT 2005;5:2929-36) with a research grant.This study was not economically supported by Novartis Pharma.BF reports receiving consulting fees from AstraZeneca, Novartis,Roche, and Wyeth; lecture fees from Astellas, Novartis, and Roche;and grant support from Novartis, Roche, Merck-Schering-Plough,Wyeth; and serving as a national coordinator for the Studyof Heart and Renal Protection (SHARP) at Oxford University’s TrialService Unit. AJ reports receiving consulting fees from Novartis,AstraZeneca, and Wyeth, and lecture fees from Novartis and Astellas;HH reports receiving consulting fees from Novartis, AstraZeneca,and Roche, and lecture fees from Novartis, AstraZeneca, Roche,and serving as a regional coordinator for the SHARP study.IH reports receiving Steering committee honorarium fromMerck, Roche, and Pfizer, and consultancy honorariums fromAstraZeneca and Merck. WM reports receiving consulting fees fromAstraZeneca and Pfizer; lecture fees from Astellas, AstraZeneca,Merck-Schering-Plough, Pfizer, and Roche; and grant support fromAventis, Pfizer, Roche and Siemens. SA, AM, and GW report nocompeting interests.

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