NT-proBNP and stem cell factor plasma concentrations are independently associated with cardiovascular outcomes in end-stage renal disease hemodialysis patients

Aims

End-stage renal disease (ESRD) treated by chronic hemodialysis (HD) is associated with poor cardiovascular (CV) outcomes, with no available evidence-based therapeutics. A multiplexed proteomic approach may identify new pathophysiological pathways associated with CV outcomes, potentially actionable for precision medicine.

Methods and results

The AURORA trial was an international, multicentre, randomized, double-blind trial involving 2776 patients undergoing maintenance HD. Rosuvastatin vs. placebo had no significant effect on the composite primary endpoint of death from CV causes, nonfatal myocardial infarction or nonfatal stroke. We first compared CV risk-matched cases and controls (n = 410) to identify novel biomarkers using a multiplex proximity extension immunoassay (276 proteomic biomarkers assessed with Olink^TM). We replicated our findings in 200 unmatched cases and 200 controls. External validation was conducted from a multicentre real-life Danish cohort [Aarhus-Aalborg (AA), n = 331 patients] in which 92 Olink^TM biomarkers were assessed. In AURORA, only N-terminal pro-brain natriuretic peptide (NT-proBNP, positive association) and stem cell factor (SCF) (negative association) were found consistently associated with the trial's primary outcome across exploration and replication phases, independently from the baseline characteristics. Stem cell factor displayed a lower added predictive ability compared with NT-ProBNP. In the AA cohort, in multivariable analyses, BNP was found significantly associated with major CV events, while higher SCF was associated with less frequent CV deaths.

Conclusions

Our findings suggest that NT-proBNP and SCF may help identify ESRD patients with respectively high and low CV risk, beyond classical clinical predictors and also point at novel pathways for prevention and treatment.

Early Conversion From Calcineurin Inhibitor- to Everolimus-Based Therapy Following Kidney Transplantation: Results of the Randomized ELEVATE Trial

In a 24-month, multicenter, open-label, randomized trial, 715 de novo kidney transplant recipients were randomized at 10-14 weeks to convert to everolimus (n = 359) or remain on standard calcineurin inhibitor (CNI) therapy (n = 356; 231 tacrolimus; 125 cyclosporine), all with mycophenolic acid and steroids. The primary endpoint, change in estimated glomerular filtration rate (eGFR) from randomization to month 12, was similar for everolimus versus CNI: mean (standard error) 0.3(1.5) mL/min/1.73² versus -1.5(1.5) mL/min/1.73² (p = 0.116). Biopsy-proven acute rejection (BPAR) at month 12 was more frequent under everolimus versus CNI overall (9.7% vs. 4.8%, p = 0.014) and versus tacrolimus-treated patients (2.6%, p < 0.001) but similar to cyclosporine-treated patients (8.8%, p = 0.755). Reporting on de novo donor-specific antibodies (DSA) was limited but suggested more frequent anti-HLA Class I DSA under everolimus. Change in left ventricular mass index was similar. Discontinuation due to adverse events was more frequent with everolimus (23.6%) versus CNI (8.4%). In conclusion, conversion to everolimus at 10-14 weeks posttransplant was associated with renal function similar to that with standard therapy overall. Rates of BPAR were low in all groups, but lower with tacrolimus than everolimus.

Single Nucleotide Polymorphisms and Long-Term Clinical Outcome in Renal Transplant Patients: A Validation Study

Genome-wide association studies (GWAS) are designed to investigate single nucleotide polymorphisms (SNPs) and the association with a clinical phenotype. A previous GWAS performed in 300 renal transplant recipients identified two SNPs (rs3811321 and rs6565887) associated with serum creatinine and clinical outcome. We sought to validate these findings. Genotyping of the two SNPs was performed using Taqman assays in 1638 Caucasians participating in the Assessment of LEscol in Renal Transplant (ALERT) study. Primary endpoint was death-censored graft loss, and secondary endpoint was all-cause mortality. Applying Cox regression, no crude association to graft loss was found for rs3811321 on chromosome 14 (hazard ratio [HR] 0.87, 95% CI 0.59-1.29, p = 0.50) or rs6565887 on chromosome 18 (HR 0.88, CI 0.62-1.25, p = 0.48). Multivariable adjustments did not change results, nor did evaluation of the number of risk alleles formed by the two SNPs. No association with mortality was detected. In conclusion, an impact of two SNPs on chromosomes 14 and 18 on death-censored graft survival or all-cause mortality was not confirmed. Our results emphasize the importance of validating findings from high-throughput genetics studies and call for large collaborative research initiatives in the field of transplantation outcomes.

Serum Calcification Propensity Is a Strong and Independent Determinant of Cardiac and All-Cause Mortality in Kidney Transplant Recipients

Calcification of the vasculature is associated with cardiovascular disease and death in kidney transplant recipients. A novel functional blood test measures calcification propensity by quantifying the transformation time (T50 ) from primary to secondary calciprotein particles. Accelerated T50 indicates a diminished ability of serum to resist calcification. We measured T50 in 1435 patients 10 weeks after kidney transplantation during 2000-2003 (first era) and 2009-2012 (second era). Aortic pulse wave velocity (APWV) was measured at week 10 and after 1 year in 589 patients from the second era. Accelerated T50 was associated with diabetes, deceased donor, first transplant, rejection, stronger immunosuppression, first era, higher serum phosphate and lower albumin. T50 was not associated with progression of APWV. During a median follow-up of 5.1 years, 283 patients died, 70 from myocardial infarction, cardiac failure or sudden death. In Cox regression models, accelerated T50 was strongly and independently associated with both all-cause and cardiac mortality, low versus high T50 quartile: hazard ratio 1.60 (95% confidence interval [CI] 1.00-2.57), ptrend   = 0.03, and 3.60 (95% CI 1.10-11.83), ptrend   = 0.02, respectively. In conclusion, calcification propensity (T50 ) was strongly associated with all-cause and cardiac mortality of kidney transplant recipients, potentially via a cardiac nonAPWV-related pathway. Whether therapeutic improvement of T50 improves outcome awaits clarification in a randomized trial.

A randomized study evaluating cinacalcet to treat hypercalcemia in renal transplant recipients with persistent hyperparathyroidism

Persistent hyperparathyroidism (HPT) after kidney transplantation (KTx) is associated with hypercalcemia, hypophosphatemia and abnormally high levels of parathyroid hormone (PTH). In this randomized trial, cinacalcet was compared to placebo for the treatment of hypercalcemia in adult patients with persistent HPT after KTx. Subjects were randomized 1:1 to cinacalcet or placebo with randomization stratified by baseline corrected total serum calcium levels (≤11.2 mg/dL [2.80 mmol/L] or >11.2 mg/dL [2.80 mmol/L]). The primary end point was achievement of a mean corrected total serum calcium value<10.2 mg/dL (2.55 mmol/L) during the efficacy period. The two key secondary end points were percent change in bone mineral density (BMD) at the femoral neck and absolute change in phosphorus; 78.9% cinacalcet- versus 3.5% placebo-treated subjects achieved the primary end point with a difference of 75.4% (95% confidence interval [CI]: 63.8, 87.1), p<0.001. There was no statistical difference in the percent change in BMD at the femoral neck between cinacalcet and placebo groups, p=0.266. The difference in the change in phosphorus between the two arms was 0.45 mg/dL (95% CI: 0.26, 0.64), p<0.001 (nominal). No new safety signals were detected. In conclusion, hypercalcemia and hypophosphatemia were effectively corrected after treatment with cinacalcet in patients with persistent HPT after KTx.

Improved patient survival with simultaneous pancreas and kidney transplantation in recipients with diabetic end-stage renal disease

AIMS/HYPOTHESIS

We aimed to determine whether simultaneous pancreas and kidney (SPK) transplantation would improve patient and kidney graft survival in diabetic end-stage renal disease (ESRD) compared with kidney transplantation alone (KTA).

METHODS

Follow-up data were retrieved for all 630 patients with diabetic ESRD who had received SPK or KTA at our centre from 1983 to the end of 2010. Recipients younger than 55 years of age received either an SPK (n = 222) or, if available, a single live donor kidney (LDK; n = 171). Older recipients and recipients with greater comorbidity received a single deceased donor kidney (DDK; n = 237). Survival was analysed by the Kaplan-Meier method and in multivariate Cox regression analysis adjusting for recipient and donor characteristics.

RESULTS

Patient survival was superior in SPK compared with both LDK and DDK recipients in univariate analysis. Follow-up time (mean ± SD) after transplantation was 7.1 ± 5.7 years. Median actuarial patient survival was 14.0 years for SPK, 11.5 years for LDK and 6.7 years for DDK recipients. In multivariate analyses including recipient age, sex, treatment modality, time on dialysis and era, SPK transplantation was protective for all-cause mortality compared with both LDK (p = 0.02) and DDK (p = 0.029) transplantation. After the year 2000, overall patient survival improved compared with previous years (HR 0.40, 95% CI 0.30, 0.55; p < 0.001). Pancreas graft survival also improved after 2000, with a 5 year graft survival rate of 78% vs 61% in previous years (1988-1999).

CONCLUSIONS/INTERPRETATION

Recipients of SPK transplants have superior patient survival compared with both LDK and DDK recipients, with improved results seen over the last decade.

Improved renal function after early conversion from a calcineurin inhibitor to everolimus: a randomized trial in kidney transplantation

In an open-label, multicenter trial, de novo kidney transplant recipients at low to medium immunological risk were randomized at week 7 posttransplant to remain on CsA (n = 100, controls) or convert to everolimus (n = 102), both with enteric-coated mycophenolate sodium and corticosteroids. The primary endpoint, change in measured GFR (mGFR) from week 7 to month 12, was significantly greater with everolimus than controls: 4.9 (11.8) mL/min versus 0.0 (12.9) mL/min (p = 0.012; analysis of covariance [ANCOVA]). Per protocol analysis demonstrated a more marked difference: an increase of 8.7 (11.2) mL/min with everolimus versus a decrease of 0.4 (12.0) mL/min in controls (p < 0.001; ANCOVA). There were no differences in graft or patient survival. The 12-month incidence of biopsy-proven acute rejection (BPAR) was 27.5% (n = 28) with everolimus and 11.0% (n = 11) in controls (p = 0.004). All but two episodes of BPAR in each group were mild. Adverse events occurred in 95.1% of everolimus patients and 90.0% controls (p = 0.19), with serious adverse events in 53.9% and 38.0%, respectively (p = 0.025). Discontinuation because of adverse events was more frequent with everolimus (25.5%) than controls (3.0%; p = 0.030). In conclusion, conversion from CsA to everolimus at week 7 after kidney transplantation was associated with a greater improvement in mGFR at month 12 versus CNI-treated controls but discontinuations and BPAR were more frequent.

Prognostic model for total mortality in patients with haemodialysis from the Assessments of Survival and Cardiovascular Events (AURORA) study

OBJECTIVES

Risk factors of mortality in patients with haemodialysis (HD) have been identified in several studies, but few prognostic models have been developed with assessments of calibration and discrimination abilities. We used the database of the Assessment of Survival and Cardiovascular Events study to develop a prognostic model of mortality over 3-4 years.

METHODS

Five factors (age, albumin, C-reactive protein, history of cardiovascular disease and diabetes) were selected from experience and forced into the regression equation. In a 67% random try-out sample of patients, no further factors amongst 24 candidates added significance (P < 0.01) to mortality outcome as assessed by Cox regression modelling, and individual probabilities of death were estimated in the try-out and test samples. Calibration was explored by calculating the prognostic index with regression coefficients from the try-out sample to patients in the 33% test sample. Discrimination was assessed by receiver operating characteristic (ROC) areas.

RESULTS

The strongest prognostic factor in the try-out sample was age, with small differences between the other four factors. Calibration in the test sample was good when the calculated number of deaths was multiplied by a constant of 1.33. The five-factor model discriminated reasonably well between deceased and surviving patients in both the try-out and test samples with an ROC area of about 0.73.

CONCLUSIONS

A model consisting of five factors can be used to estimate and stratify the probability of death for individuals The model is most useful for long-term prognosis in an HD population with survival prospects of more than 1 year.

Quality of life in kidney donors

Reports on quality of life of kidney donors include small populations with variable response rates. The aim was to evaluate quality of life in kidney donors in a large cross-sectional study. Through the Norwegian Renal Registry we contacted all 1984 kidney donors in the period 1963-2007 with a response rate of 76%. All received the Short-Form-36 (SF-36) survey form and a questionnaire specifically designed for kidney donors. SF-36 scores for a subgroup (n = 1414) of kidney donors were not inferior to a general population sample, adjusted for age, gender and education. When asked to reconsider, a majority stated that they still would have consented to donate. Risk factors for having doubts were graft loss in the recipient (OR 3.1, p < 0.001), medical problems after donation (OR 3.7, p < 0.001), unrelated donor (OR 2.2, p = 0.01) and less than 12 years since donation (OR 1.8, p = 0.04). Older age at donation was associated with lower risk (OR 0.98, p = 0.03). Compared with other donors, those expressing doubts had inferior SF-36 scores. Norwegian kidney donors are mostly first-degree relatives. They are fully reimbursed and offered life-long follow-up. All inhabitants are provided universal healthcare. This should be considered when extrapolating these results to other countries.

Cardiovascular outcomes and their relationships to lipoprotein components in patients with and without chronic kidney disease: results from the IDEAL trial

OBJECTIVES

In Incremental Decrease in Endpoints through Aggressive Lipid-lowering (IDEAL), we compared cardiovascular outcomes in patients with and without chronic kidney disease (CKD) (estimated glomerular filtration rate <60 mL min(-1) 1.73 m(-2)) and analysed relationships between lipoprotein components (LC) and major coronary events (MCE) and other cardiovascular (CV) events.

DESIGN

Exploratory analysis of CV endpoints in a randomized trial comparing high dose of atorvastatin to usual dose of simvastatin on MCE.

SETTINGS

Patients with CKD were compared with the non-CKD patients. Cox regression models were used to study the relationships between on-treatment levels of LC and incident MCE.

FINDINGS

Chronic kidney disease was strongly associated with cardiovascular end-points including total mortality. In patients with CKD, a significant benefit of high dose atorvastatin treatment was found for any CV events, stroke and peripheral artery disease, but not for MCE. However, all cardiovascular end-points except stroke and CV mortality were reduced in the non-CKD group. Differential changes in LC or relationships to LC could not explain the different treatment outcomes in MCE in the two groups.

INTERPRETATION

Chronic kidney disease was a powerful risk factor for all cardiovascular end-points. The reason why the significant reductions achieved by high-dose statin treatment in most CV end-points in the non-CKD group were only in part matched by similar reductions in the CKD patients is not apparent. This difference did not result from differential changes in or relations to LC, but limited power may have increased the possibility of chance findings.

Early, abrupt conversion of de novo renal transplant patients from cyclosporine to everolimus: results of a pilot study

In a single-center study, 20 kidney transplant patients without prior rejection were abruptly converted from cyclosporine to everolimus at seven wk post-transplant. All patients received basiliximab induction with maintenance enteric-coated mycophenolate sodium and corticosteroids. Biopsy-proven acute rejection had occurred in three of 20 patients (15.0%) by the end of week seven post-conversion. All episodes were mild and reversible, with subsequent recovery of renal function. Calculated glomerular filtration rate (GFR) improved significantly (51 +/- 11 mL/min at time of conversion, 58 +/- 12 mL/min at week seven post-conversion, 57 +/- 17 mL/min at month six post-conversion; p = 0.001). No patient developed proteinuria in the nephrotic range. Twenty-two adverse events were reported in 10 patients, three of which had a suspected relationship to everolimus. Mean leukocyte and platelet count decreased significantly, and triglyceride level increased. This study suggests that kidney transplant patients without prior rejection can be converted abruptly from cyclosporine to everolimus at seven wk post-transplant, resulting in significantly improved renal function with no apparent increase, in risk of rejection and good tolerability.

The impact of early-diagnosed new-onset post-transplantation diabetes mellitus on survival and major cardiac events

The impact of early-diagnosed new-onset post-transplantation diabetes mellitus (PTDM) on cardiovascular (CV) disease is not well described. The objectives of the present prospective single-center observational study were to assess the long-term effects of early-diagnosed new-onset PTDM on major cardiac events (MCE; cardiac death or nonfatal acute myocardial infarction) and patient survival. Diabetic status and CV risk factors were assessed in 201 consecutive renal allograft recipients 3 months after transplantation (baseline) during a period of 16 months (1995-96). Follow-up data until January 1, 2004 were obtained from the Norwegian Renal Registry. The 8-year (range 7-9 years) cumulative incidence of MCEs was 7% (nine out of 138) in recipients without diabetes, 20% (seven out of 35) in patients with new-onset PTDM and 21% (six out of 28) in patients with diabetes mellitus before transplantation (DM). Proportional hazards regression analyses (forward stepwise regression) revealed that patients with PTDM had an approximately three-fold increased risk of MCEs as compared with nondiabetic patients (hazard ratio (HR)=3.27, 95% confidence interval (CI)=1.22-8.80, P=0.019). A total of 61 patients (30%) died. Eight-year patient survival was 80% in the nondiabetic group, 63% in the PTDM group and 29% in the DM group, respectively. Pretransplant diabetes (HR=5.09, 95% CI=2.60-9.96, P<0.001), age (HR=1.03, 95% CI=1.01-1.05, P=0.016), cytomegalovirus (CMV) infection (HR=2.66, 95% CI=1.27-5.53, P=0.009), and creatinine clearance (HR=0.98, 95% CI=0.96-1.00, P=0.046), but not PTDM (HR=1.20, 95% CI=0.58-2.49, P=0.621), were independent predictors of death in the multiple Cox regression model. Early-diagnosed PTDM is a predictor of MCEs, but not of all-cause mortality, the first 8 years after renal transplantation.

Evaluation of the pharmacokinetic interaction between fluvastatin XL and cyclosporine in renal transplant recipients

OBJECTIVE

To assess the pharmacokinetic interaction between cyclosporine and extended-release fluvastatin (fluvastatin XL), 80 mg for 7 days, in stable renal transplant recipients.

METHODS

This was a single-center, open-label study. 17 renal transplant recipients received their standard cyclosporine therapy (Days 1 - 9) plus a once-daily single oral dose of fluvastatin XL, 80 mg (Days 2 - 8). Blood samples were collected and cyclosporine (whole blood) and fluvastatin (plasma) concentrations determined by radioimmunoassay and HPLC fluorescence detection, respectively. Pharmacokinetic parameters were calculated using non-compartment analysis and fluvastatin results were compared with historical controls.

RESULTS

Treatment with fluvastatin XL, 80 mg for 7 days, had no significant effect on either the AUC0-12 (3,644 ng x h/ml in the absence of fluvastatin vs. 3,534 ng x h/ml in the presence of fluvastatin) or the Cmax of cyclosporine (983 ng/ml in the absence of fluvastatin vs. 945 ng/ml in the presence of fluvastatin). Co-administration of fluvastatin XL also had no effect on the tmax, t1/2 or apparent clearance (CL/F) of cyclosporine in renal transplant patients. The AUC and Cmax for fluvastatin XL in the presence of cyclosporine (AUC0-24 1,192 ng. x h/ml, Cmax 271 ng/ml) were approximately 2-fold higher compared with historical data for fluvastatin XL alone in healthy volunteers (AUC0-24 630 ng x h/ml, Cmax 102 ng/ml) but lower than the historical data for fluvastatin IR, 40 mg b.i.d. alone in healthy volunteers (AUC0-24 1,340 ng x h/ml, Cmax 443 ng/ml). Tmax, t1/2 and trough levels of fluvastatin in the presence of cyclosporine were also similar to the historical controls. Concomitant administration of cyclosporine and fluvastatin XL was well tolerated by renal transplant recipients.

CONCLUSIONS

Fluvastatin XL, 80 mg, and cyclosporine do not show clinically relevant pharmacokinetic interactions.

Combined therapy with atorvastatin and calcineurin inhibitors: no interactions with tacrolimus

Increased systemic exposure to statins and consequent risk for complications has been reported in patients concomitantly treated with cyclosporin A (CsA). This has been ascribed to inhibition of drug catabolism by cytochrome P450 3A4 (CYP3A4) or drug transport by P-glycoprotein (PGP) and organic anion transporting polypeptide (OATP1B1). It is not known whether the combination of statins and tacrolimus (Tac) also suffers from this drawback. Therefore, a pharmacokinetic study of atorvastatin and its metabolites was performed in 13 healthy volunteers after 4 days' treatment, and after short (12 h) concomitant exposure to CsA and Tac. A complementary assessment of overall CYP, and hepatic and intestinal CYP3A4+PGP activity was performed after each treatment episode and compared to baseline (no drugs). Systemic exposure to atorvastatin acid and its metabolites was significantly increased when administered with CsA. In contrast, intake of Tac did not have any impact on atorvastatin pharmacokinetics. Concomitantly, a profound decrease of hepatic and intestinal PGP and an increase of intestinal CYP3A4 were noted with CsA, whereas no effect was seen after atorvastatin therapy with or without Tac. Based on these findings treatment with Tac appears a safer option for patients needing a combination of statins and calcineurin inhibitors.

Long-term cardiac outcomes in renal transplant recipients receiving fluvastatin: the ALERT extension study

Renal transplant recipients (RTR) have an increased risk of premature cardiovascular disease. The ALERT study is the first trial to evaluate the effect of statin therapy on cardiac outcomes following renal transplantation. Patients initially randomized to fluvastatin or placebo in the 5-6 year ALERT study were offered open-label fluvastatin XL 80 mg/day in a 2-year extension to the original study. The primary endpoint was time to first major adverse cardiac event (MACE). Of 1787 patients who completed ALERT, 1652 (92%) were followed in the extension. Mean total follow-up was 6.7 years. Mean LDL-cholesterol was 98 mg/dL (2.5 mmol/L) at last follow-up compared to a pre-study level of 159 mg/dL (4.1 mmol/L). Patients randomized to fluvastatin had a reduced risk of MACE (hazards ratio [HR] 0.79, 95% CI 0.63-0.99, p = 0.036), and a 29% reduction in cardiac death or definite non-fatal MI (HR 0.71, 95% CI 0.55-0.93, p = 0.014). Total mortality and graft loss did not differ significantly between groups. Fluvastatin produces a safe and effective reduction in LDL-cholesterol associated with reduced risk of MACE in RTR. The lipid-lowering and cardiovascular benefits of fluvastatin are comparable to those of statins in other patient groups, and support use of fluvastatin in RTR.

Combined therapy with atorvastatin and calcineurin inhibitors: no interactions with tacrolimus

Increased systemic exposure to statins and consequent risk for complications has been reported in patients concomitantly treated with cyclosporin A (CsA). This has been ascribed to inhibition of drug catabolism by cytochrome P450 3A4 (CYP3A4) or drug transport by P-glycoprotein (PGP) and organic anion transporting polypeptide (OATP1B1). It is not known whether the combination of statins and tacrolimus (Tac) also suffers from this drawback. Therefore, a pharmacokinetic study of atorvastatin and its metabolites was performed in 13 healthy volunteers after 4 days' treatment, and after short (12 h) concomitant exposure to CsA and Tac. A complementary assessment of overall CYP, and hepatic and intestinal CYP3A4+PGP activity was performed after each treatment episode and compared to baseline (no drugs). Systemic exposure to atorvastatin acid and its metabolites was significantly increased when administered with CsA. In contrast, intake of Tac did not have any impact on atorvastatin pharmacokinetics. Concomitantly, a profound decrease of hepatic and intestinal PGP and an increase of intestinal CYP3A4 were noted with CsA, whereas no effect was seen after atorvastatin therapy with or without Tac. Based on these findings treatment with Tac appears a safer option for patients needing a combination of statins and calcineurin inhibitors.

Renal dysfunction is a strong and independent risk factor for mortality and cardiovascular complications in renal transplantation

Renal transplant recipients (RTR) have shortened life expectancy, primarily due to premature cardiovascular disease (CVD). Traditional CVD risk factors are highly prevalent. In addition, several non-traditional risk factors may contribute to the high risk. The aim of the study was to evaluate the effects of renal dysfunction on mortality and cardiovascular complications in 1052 placebo-treated patients of the Assessment of LEscol in Renal Transplantation (ALERT) trial. Follow-up was 5-6 years and endpoints included cardiac death, non-cardiovascular death, all-cause mortality, major adverse cardiac event (MACE), non-fatal myocardial infarction (MI) and stroke. The effects of serum creatinine at baseline on these endpoints were evaluated. Elevated serum creatinine in RTR was a strong and independent risk factor for MACE, cardiac, non-cardiovascular, and all-cause mortality, but not for stroke or non-fatal MI alone. Serum creatinine was associated with increased mortality and MACE, independent of established CVD risk factors. Graft loss resulted in increased incidences of non-cardiovascular death, all-cause mortality, MACE and non-fatal MI. In conclusion, elevated serum creatinine is a strong risk factor for all-cause, non-cardiovascular and cardiac mortality, and MACE, independent of traditional risk factors, but not for stroke or non-fatal MI alone.

Acute renal allograft rejections, a role for statins?

Acute rejection of kidney allografts during the first months following transplantation is one of the most important risk factor for long-term graft failure. Some small open studies have indicated that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-Co-A), statins, might act as immunosuppressive agents, and reduce acute rejection rates. Moreover, the use of statin in transplant recipients is quite common, despite no data from prospective large multi-centre studies are available to demonstrate any beneficial effect for acute rejections or long-term cardiovascular protection in this population. In this overview, recent clinical and experimental data will be provided for assessing statins as immunosuppressive agents. Although in vitro studies have provided a theoretical basis for the use of statins as immunosuppressive agents, more recent clinical placebo controlled studies have failed to confirm the initial optimism of this effect of statins.

Sustained improvement of renal graft function for two years in hypertensive renal transplant recipients treated with nifedipine as compared to lisinopril

BACKGROUND

Treatment of posttransplant hypertension is still a matter of debate. Calcium antagonists may ameliorate renal side effects of cyclosporin. Angiotensin converting enzyme- (ACE) inhibitors may be more effective in sustaining renal function in native chronic renal disease. We prospectively compared the effect of controlled release nifedipine and lisinopril on long-term renal function in hypertensive kidney transplant patients treated with cyclosporin.

METHODS

A total of 154 renal transplant patients presenting with hypertension (diastolic blood pressure >or=95 mmHg) during the first 3 weeks after transplantation were randomised to receive double-blind nifedipine 30 mg or lisinopril 10 mg once daily. A total of 123 patients completed 1 year of treatment (69 nifedipine, 54 lisinopril) and 64 patients completed 2 years of double-blind treatment (39 nifedipine, 25 lisinopril). Baseline glomerular filtration rate was measured as 99 mTc-diethylene-triaminepentaacetate clearance in a stable phase 2 to 5 weeks after inclusion and repeated at 1 and 2 years.

RESULTS

Baseline glomerular filtration rates were similar (46+/-16 ml/min with nifedipine, 43+/-14 ml/min with lisinopril). The changes in glomerular filtration rates from baseline were statistically significant between the groups after 1 year (9.6 ml/min mean treatment difference (95% confidence interval [CI]s 5.5-13.7 ml/min, P=0.0001) and remained statistically significant also after 2 years (10.3 ml/min mean difference (95% CIs 4.0-16.6], P=0.0017). After 1 year glomerular filtration rates averaged 56+/-19 ml/min in the nifedipine group and 44+/-14 ml/min in the lisinopril group.

CONCLUSIONS

Both nifedipine and lisinopril were safe and effective in treatment of hypertension in renal transplant patients treated with cyclosporin. Patients receiving nifedipine but not lisinopril improved kidney transplant function over a period of 2 years.

Efficacy of nifedipine or lisinopril in the treatment of hypertension after renal transplantation: a double-blind randomised comparative trial

Calcium channel blockers and angiotensin converting enzyme-inhibitors are commonly used in the treatment of hypertensive renal transplant recipients. The purpose of this study was to investigate if the response rate to treatment differs with these drugs in this setting. A single centre, prospective, randomised, double-blinded, comparative study to address the efficacy of controlled release nifedipine or lisinopril in the treatment of hypertension (diastolic blood pressure > or =95 mmHg) in cyclosporin (CsA)-treated renal transplant recipients was performed. Recipients were randomised to receive either lisinopril (10 mg once daily) or controlled release nifedipine (30 mg once daily). The dose was doubled on indication. The number of responders (diastolic blood pressure <90 mmHg on monotherapy) were addressed during the early post-transplant phase (first 3 months) and during a late post-transplant phase (from 3 to 12 months after renal transplantation) in the same patient population. One hundred and fifty-four patients (nifedipine=78, lisinopril=76) with untreated hypertension (diastolic blood pressure> or =95 mmHg) were randomised within 3 wk after renal transplantation. One hundred and twenty-three patients (nifedipine=69, lisinopril=54) completed the study. Fourteen (20%) nifedipine-treated recipients responded during the early, and 26 (38%) during the late post-operative phase (months 4-12 after renal transplantation). Eleven (20%) lisinopril-treated recipients responded during the early, and 18 (33%) during the late post-transplant phase. Non-responders were, on average, 8.5+/-1.5 kg heavier both in the early phase and after 1 yr of treatment (p<0.01), and 6.1+/-0.9 yr older than responders (p<0.05). In conclusion, these results indicate that both controlled release nifedipine and lisinopril are equally efficient in the treatment of post-transplant hypertension. As monotherapy, both drugs show a "response rate" of 20-38%, depending on time interval after transplantation.

Bilateral pharmacokinetic interaction between cyclosporine A and atorvastatin in renal transplant recipients

Atorvastatin is increasingly used as a cholesterol-lowering agent in solid organ transplant recipients receiving cyclosporine A (CsA). However, the potential bilateral pharmacokinetic interaction between atorvastatin and CsA in renal transplant recipients has not previously been examined. Baseline 12-h CsA pharmacokinetic investigation was performed in 21 renal transplant recipients and repeated after 4 weeks of atorvastatin treatment (10 mg/ d). At week 4, 24-h pharmacokinetics of atorvastatin was also performed. All patients received basiliximab induction followed by CsA and prednisolone immunosuppression. Compared with historic controls, CsA-treated patients showed, on average, sixfold higher plasma HMG-CoA reductase inhibitory activity after 4 weeks of atorvastatin treatment (p < 0.05). Atorvastatin had a moderate effect on the pharmacokinetics of CsA and reduced the AUC0-12 (area under curve, 0-12h) by 9.5 +/- 18% (p = 0.013) and Cmax (maximal concentration) by 13.5 +/- 24% (p =0.009), while C12 (trough level) was unchanged (p =0.42). Total and LDL cholesterol decreased by 26.8 +/- 8.4% (p < 0.0001) and 41.5 +/- 11.0% (p < 0.0001), respectively. Bilateral pharmacokinetic interaction between atorvastatin and CsA resulted in sixfold higher plasma HMG-CoA reductase inhibitory activity, but only a moderate decrease in systemic exposure of CsA.

Effect of fluvastatin on acute renal allograft rejection: a randomized multicenter trial

BACKGROUND

Statin therapy has been reported to reduce the acute rejection rate following renal transplantation in a pilot study. The present study is the first randomized, double-blind and adequately powered study to examine the effect of statins on acute rejection of renal allografts.

METHODS

A total of 364 patients were randomly assigned to receive either fluvastatin 40 mg or placebo in combination with conventional cyclosporine-based immunosuppressive therapy. The primary end point was treated first acute rejection. Secondary end points included biopsy-proven rejection, histological severity of rejection, occurrence of steroid-resistant rejection, and serum creatinine at three months following transplantation.

RESULTS

Fluvastatin was well tolerated; no patients developed myositis or rhabdomyolysis. There was no difference in the acute rejection rate [86 (47.3%) fluvastatin vs. 87 (47.8%) placebo] and no significant difference in the severity of rejection, steroid resistant rejection or mean serum creatinine at three months (160 micromol/L vs. 160 micromol/L). Total cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol and triglyceride levels increased following renal transplantation. With the exception of the increase in HDL-C, which was augmented, the increases in lipid parameters were significantly reduced by fluvastatin (total cholesterol +17.5% vs. 35.7%; LDL-C +6.3% vs. 46.7%; HDL-C +43.3% vs. 38.1%; triglyceride +52.2% vs 77.6%).

CONCLUSIONS

Contrary to the reported effects of statins, fluvastatin had no effect on the incidence or severity of acute rejection following renal transplantation. There were no increases in adverse events. A significant and potentially beneficial alteration in the lipid profile was observed in the early post transplant period. We conclude that fluvastatin may be used safely to correct dyslipidemia in patients with end-stage renal failure through the peri-transplant period.

Effects of fluvastatin on cardiac events in renal transplant patients: ALERT (Assessment of Lescol in Renal Transplantation) study design and baseline data

BACKGROUND

Recent clinical trials of primary and secondary prevention of cardiovascular disease have demonstrated that lowering plasma cholesterol with 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors ('statins') reduces morbidity and mortality from coronary heart disease in diverse patient populations.

STUDY AIMS

The aim of the present ALERT (Assessment of Lescol in Renal Transplantation) study is to determine whether renal transplant recipients would also benefit from statin therapy. ALERT is a multicentre, randomized, double-blind, placebo-controlled trial to assess the effect of fluvastatin in renal transplant recipients with mild-to-moderate hypercholesterolaemia. The primary objective is to investigate the effects of fluvastatin on major adverse cardiac events (MACE). In addition, the effects on cardiovascular and all-cause mortality, as well as renal function, will be addressed.

STUDY POPULATION

The study population contains patients with functioning renal allografts of more than 6 months' duration, recruited from 75 centres in Northern Europe and Canada. Patients of both sexes, aged 30-75 years, with a total cholesterol level of 4.0-9.0 mmol/l (155-348 mg/dl) were included, except for those with a history of myocardial infarction, where the upper limit for inclusion was 7.0 mmol/l (270 mg/dl).

STUDY DESIGN

A total of 2100 patients were recruited by the end of October 1997 and will be followed for up to 6 years. This report presents the design features of the study (recruitment, follow-up, sample size, data analysis and study organization), along with baseline results. ALERT is the first large-scale prospective, randomized, double-blind study to address the prevention of cardiovascular mortality in renal transplant patients receiving an HMGCoA reductase inhibitor.

Atorvastatin improves endothelial function in renal-transplant recipients

BACKGROUND

Hyperlipidaemia and endothelial dysfunction are common features in cyclosporin A (CsA)-treated renal transplant recipients. Endothelial dysfunction may contribute to the risk of premature atherosclerosis and cardiovascular death in these patients. A beneficial effect of statin therapy beyond cholesterol lowering may be an improvement of endothelial function. The present study was designed to assess the effect of atorvastatin on serum lipids and endothelial function in CsA treated renal transplant recipients.

METHODS

This pilot study was an open trial of 4 weeks atorvastatin (10 mg per day) treatment in renal transplant recipients (n=22). All patients received a CsA- and prednisolone-based immunosuppressive regimen. Endothelial function was assessed in the forearm skin microvasculature by acetylcholine stimulation and laser Doppler flowmetry, before and after atorvastatin treatment. Serum lipids, plasma endothelin-1 (ET-1), nitric oxide (NO), and von Willebrand factor (vWF) were also measured.

RESULTS

Both total and LDL cholesterol were significantly reduced by 26.8 +/- 8.4 and 41.5 +/- 11.0% respectively, after 4 weeks of treatment. Endothelial function was significantly improved during atorvastatin treatment, area under the flux versus time curve (AUC)(ACh) was 538 +/- 362 AU x min before and 682 +/- 276 AU x min after treatment (P=0.042). Plasma NO levels also showed a borderline significant increase from 49 +/- 30 to 57 +/- 37 micromol/l during the treatment period (P=0.051), though plasma ET-1 (0.37+/-0.08 vs 0.37+/-0.12 fmol/ml) and vW (196+/-57 vs 197+/-37%) were unchanged.

CONCLUSION

Atorvastatin lowered serum cholesterol significantly and improved endothelial function in renal transplant recipients after 4 weeks of treatment. Plasma NO levels were increased during atorvastatin treatment, indicating a possible endothelial protective effect through an "endothelial-NO pathway".

Reduction of left ventricular mass by lisinopril and nifedipine in hypertensive renal transplant recipients: a prospective randomized double-blind study

BACKGROUND

Cardiovascular disease is the dominant cause of death in renal transplant recipients. Left ventricular hypertrophy (LVH) is a known risk factor. After renal transplantation, persistent hypertension is an important determinant for the further evolution of LVH. The aim of the present study was to compare the effect of an angiotensin converting enzyme (ACE) inhibitor (lisinopril) with a calcium channel blocker (CCB) (controlled release nifedipine) in treatment of posttransplant hypertension focusing on changes in LVH.

METHODS

One hundred fifty-four renal transplant recipients presenting with hypertension (diastolic BP> or =95 mmHg) during the first 3 weeks after transplantation were randomized to receive double-blind 30 mg nifedipine or 10 mg lisinopril once daily.

RESULTS

One hundred twenty-three patients completed 1 year of treatment. Good quality echocardiographic data were available in 116 recipients (62 nifedipine/54 lisinopril) 2 and 12 months posttransplant. Blood pressure was equally well controlled in the two groups throughout the study (mean systolic/diastolic+/-SD after 1 year: 140+/-16/87+/-8 mmHg with nifedipine and 136+/-17/85+/-8 mmHg with lisinopril). Left ventricular mass index was reduced by 15% (P<0.001) in both groups (from 153+/-43 to 131+/-38 g/m2 with nifedipine and from 142+/-35 to 121+/-34 g/m2 with lisinopril). There were no statistically significant differences between the two treatment groups at baseline or at follow-up.

CONCLUSIONS

In hypertensive renal transplant recipients with well-controlled blood pressure, there is a regression of left ventricular mass after renal transplantation. The regression of left ventricular mass index is observed to a similar extent in patients treated with lisinopril or nifedipine.

Effects of fluvastatin on cardiac events in renal transplant patients: ALERT (Assessment of Lescol in Renal Transplantation) study design and baseline data

BACKGROUND

Recent clinical trials of primary and secondary prevention of cardiovascular disease have demonstrated that lowering plasma cholesterol with 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors ('statins') reduces morbidity and mortality from coronary heart disease in diverse patient populations.

STUDY AIMS

The aim of the present ALERT (Assessment of Lescol in Renal Transplantation) study is to determine whether renal transplant recipients would also benefit from statin therapy. ALERT is a multicentre, randomized, double-blind, placebo-controlled trial to assess the effect of fluvastatin in renal transplant recipients with mild-to-moderate hypercholesterolaemia. The primary objective is to investigate the effects of fluvastatin on major adverse cardiac events (MACE). In addition, the effects on cardiovascular and all-cause mortality, as well as renal function, will be addressed.

STUDY POPULATION

The study population contains patients with functioning renal allografts of more than 6 months' duration, recruited from 75 centres in Northern Europe and Canada. Patients of both sexes, aged 30-75 years, with a total cholesterol level of 4.0-9.0 mmol/l (155-348 mg/dl) were included, except for those with a history of myocardial infarction, where the upper limit for inclusion was 7.0 mmol/l (270 mg/dl).

STUDY DESIGN

A total of 2100 patients were recruited by the end of October 1997 and will be followed for up to 6 years. This report presents the design features of the study (recruitment, follow-up, sample size, data analysis and study organization), along with baseline results. ALERT is the first large-scale prospective, randomized, double-blind study to address the prevention of cardiovascular mortality in renal transplant patients receiving an HMGCoA reductase inhibitor.

The use of pretransplant erythropoietin to normalize hemoglobin levels has no deleterious effects on renal transplantation outcome

BACKGROUND

The aim of this study was to establish the outcome of renal transplantation in patients given pretransplant erythropoietin (EPO) treatment targeted at reaching a normal hemoglobin concentration (Hb), compared to those given EPO-treatment aimed at maintaining subnormal Hb.

METHODS

A total of 416 patients from Scandinavian countries and with renal anaemia were enrolled to examine the effects of increasing Hb from a subnormal level (90-120 g/liter) to a normal level (135-160 g/liter) by EPO treatment. Half of the patients were randomized to have their Hb increased, with the other half randomized to maintain a subnormal Hb. Thirty-two patients from the normal Hb group and 24 patients from the subnormal group received a renal graft during the study period. The outcomes of these transplantations were examined prospectively for 6 months.

RESULTS

Preoperative Hb levels were 143+/-17 and 121+/-14 g/liter in the two groups, respectively (P<0.0001). The Hb remained higher in the normal Hb group during the first 2 weeks after transplantation. The percentage of patients requiring postoperative blood transfusions in the normal Hb group was 16%, compared with 50% in the subnormal group (P<0.01). No statistically significant difference in the proportion of functioning grafts or in the serum creatinine levels could be detected. No correlation between EPO treatment and creatinine levels after transplantation was found. The frequency of adverse events was similar in the two groups.

CONCLUSIONS

EPO treatment aimed at reaching a normal Hb in renal transplant recipients reduces the postoperative requirement for blood transfusions and has no deleterious effects on kidney graft function.