Cardiovascular outcomes in the outpatient kidney transplant clinic: the Framingham risk score revisited

Cardiovascular risk trajectory and its associated factors among candidates on the waiting list for deceased-donor kidney transplantation: A longitudinal study

BACKGROUND

Cardiovascular disease is a significant cause of morbidity and mortality for wait-listed kidney transplant candidates. Since cardiovascular risk is related to a variety of factors and may change with time, longitudinal changes in cardiovascular risk and related factors in candidates need to be investigated.

OBJECTIVES

This study aimed to examine the trajectory of the cardiovascular risk score and its related factors in patients on the waiting list for deceased-donor kidney transplantation (DDKT).

METHODS

This longitudinal study enrolled 144 patients who were registered as candidates for a DDKT at a transplant center in South Korea. During the 5-year follow-up period, 3 candidates on the waiting list were transferred to other hospitals, 19 candidates died, and 31 candidates received kidney transplantation.

RESULTS

Approximately 26.6 % of the candidates had a high level of cardiovascular risk, and this increased to 53.2 % after 5 years. A high risk of psychosocial status (β=0.351, p=.026) was the most significant predictor of cardiovascular risk, followed by higher comorbidity (β=0.263, p<.001). Comorbidities were a significant factor associated with cardiovascular risk throughout the 5-year period, whereas the duration of dialysis and waiting time were significant only within 1 year after baseline.

CONCLUSION

Cardiovascular risk during 5 years on the waiting list for DDKT was associated with multidimensional factors, including psychosocial status before transplantation, comorbidity, waiting time for transplantation, and the duration of dialysis. In addition to managing comorbid conditions, shortening the waiting time and duration of dialysis is important for reducing cardiovascular risk during the long-term care of candidates on the waiting list for DDKT.

Inflammation in the early phase after kidney transplantation is associated with increased long-term all-cause mortality

In the general population, low-grade inflammation has been established as a risk factor for all-cause mortality. We hypothesized that an inflammatory milieu beyond the time of recovery from the surgical trauma could be associated with increased long-term mortality in kidney transplant recipients (KTRs). This cohort study included 1044 KTRs. Median follow-up time post-engraftment was 10.3 years. Inflammation was assessed 10 weeks after transplantation by different composite inflammation scores based on 21 biomarkers. We constructed an overall inflammation score and five pathway-specific inflammation scores (fibrogenesis, vascular inflammation, metabolic inflammation, growth/angiogenesis, leukocyte activation). Mortality was assessed with Cox regression models adjusted for traditional risk factors. A total of 312 (29.9%) patients died during the follow-up period. The hazard ratio (HR) for death was 4.71 (95% CI: 2.85-7.81, p < .001) for patients in the highest quartile of the overall inflammation score and HRs 2.35-2.54 (95% CI: 1.40-3.96, 1.52-4.22, p = .001) for patients in the intermediate groups. The results were persistent when the score was analyzed as a continuous variable (HR 1.046, 95% CI: 1.033-1.056, p < .001). All pathway-specific analyses showed the same pattern with HRs ranging from 1.19 to 2.70. In conclusion, we found a strong and consistent association between low-grade systemic inflammation 10 weeks after kidney transplantation and long-term mortality.

Renal transplant outcomes in amyloidosis

BACKGROUND

Outcomes after renal transplantation have traditionally been poor in systemic amyloid A (AA) amyloidosis and systemic light chain (AL) amyloidosis, with high mortality and frequent recurrent disease. We sought to compare outcomes with matched transplant recipients with autosomal dominant polycystic kidney disease (ADPKD) and diabetic nephropathy (DN), and identify factors predictive of outcomes.

METHODS

We performed a retrospective cohort study of 51 systemic AL and 48 systemic AA amyloidosis patients undergoing renal transplantation. Matched groups were generated by propensity score matching. Patient and death-censored allograft survival were compared via Kaplan-Meier survival analyses, and assessment of clinicopathological features predicting outcomes via Cox proportional hazard analyses.

RESULTS

One-, 5- and 10-year death-censored unadjusted graft survival was, respectively, 94, 91 and 78% for AA amyloidosis, and 98, 93 and 93% for AL amyloidosis; median patient survival was 13.1 and 7.9 years, respectively. Patient survival in AL and AA amyloidosis was comparable to DN, but poorer than ADPKD [hazard ratio (HR) = 3.12 and 3.09, respectively; P < 0.001]. Death-censored allograft survival was comparable between all groups. In AL amyloidosis, mortality was predicted by interventricular septum at end diastole (IVSd) thickness >12 mm (HR = 26.58; P = 0.03), while survival was predicted by haematologic response (very good partial or complete response; HR = 0.07; P = 0.018). In AA amyloidosis, recurrent amyloid was associated with elevated serum amyloid A concentration but not with outcomes.

CONCLUSIONS

Renal transplantation outcomes for selected patients with AA and AL amyloidosis are comparable to those with DN. In AL amyloidosis, IVSd thickness and achievement of deep haematologic response pre-transplant profoundly impact patient survival.

Early cardiovascular events and cardiovascular death after renal transplantation: role of pretransplant risk factors

BACKGROUND

The purpose of this study was to verify the risk factors present in patients on the kidney transplant waiting list that may interfere with the incidence of cardiovascular (CV) events and death during the first 12 months after transplantation.

METHODS

Based on the data collected prospectively during pretransplant workups, a retrospective study was conducted including 665 patients followed up until death or completing 12 months posttransplantation. Endpoints were the composite incidence of CV events and death.

RESULTS

The prevalence of diabetes, LV hypertrophy, and CV disease at baseline was high; 14% of patients had angina, 26% an abnormal myocardial scan, and 47% coronary artery disease. CV events occurred in 53 patients (8.4%) and in 29 (55%) caused death. The independent predictors of events were age ≥ 50 years (HR 2.292; CI% 1.093-4.806), angina (HR 1.969; CI% 1.039-3.732), and altered myocardial scan (HR 1.905, CI% 1.059-3.428). Altered myocardial scan (HR 2.822, 95% CI 1.095-6.660) was also one of the independent predictor of CV death.

CONCLUSION

The incidence of CV events and death were predicted by variables associated with myocardial ischemia, a potentially modifiable risk factor. Patients with pretransplantation myocardial ischemia should be considered at a higher risk of developing early CV complications and managed accordingly before, during, and after kidney transplantation.

Lifestyle, Inflammation, and Vascular Calcification in Kidney Transplant Recipients: Perspectives on Long-Term Outcomes

After decades of pioneering and improvement, kidney transplantation is now the renal replacement therapy of choice for most patients with end-stage kidney disease (ESKD). Where focus has traditionally been on surgical techniques and immunosuppressive treatment with prevention of rejection and infection in relation to short-term outcomes, nowadays, so many people are long-living with a transplanted kidney that lifestyle, including diet and exposure to toxic contaminants, also becomes of importance for the kidney transplantation field. Beyond hazards of immunological nature, a systematic assessment of potentially modifiable-yet rather overlooked-risk factors for late graft failure and excess cardiovascular risk may reveal novel targets for clinical intervention to optimize long-term health and downturn current rates of premature death of kidney transplant recipients (KTR). It should also be realized that while kidney transplantation aims to restore kidney function, it incompletely mitigates mechanisms of disease such as chronic low-grade inflammation with persistent redox imbalance and deregulated mineral and bone metabolism. While the vicious circle between inflammation and oxidative stress as common final pathway of a multitude of insults plays an established pathological role in native chronic kidney disease, its characterization post-kidney transplant remains less than satisfactory. Next to chronic inflammatory status, markedly accelerated vascular calcification persists after kidney transplantation and is likewise suggested a major independent mechanism, whose mitigation may counterbalance the excess risk of cardiovascular disease post-kidney transplant. Hereby, we first discuss modifiable dietary elements and toxic environmental contaminants that may explain increased risk of cardiovascular mortality and late graft failure in KTR. Next, we specify laboratory and clinical readouts, with a postulated role within persisting mechanisms of disease post-kidney transplantation (i.e., inflammation and redox imbalance and vascular calcification), as potential non-traditional risk factors for adverse long-term outcomes in KTR. Reflection on these current research opportunities is warranted among the research and clinical kidney transplantation community.

Comparison of different algorithms for the assessment of cardiovascular risk after kidney transplantation by the time of entering waiting list

BACKGROUND

The prevalence of cardiovascular disease is high among patients with chronic kidney disease and cardiovascular events (CVE) remain the leading cause of death after kidney transplantation (KT). We performed a retrospective analysis of 389 KT recipients to assess if the European Society of Cardiology Score (ESC-Score), Framingham Heart Study Score (FRAMINGHAM), Prospective Cardiovascular Munster Study Score (PROCAM-Score) or Assessing cardiovascular risk using Scottish Intercollegiate Guidelines Network Score (ASSIGN-Score) algorithms can predict cardiovascular risk after KT at the time of entering the waiting list.

METHODS

389 KT candidates were scored by the time of entering the waiting list. Pearsons chi-square test, cox regression analysis and survival estimates were performed to evaluate the reliability of the cardiovascular scoring models after successful KT.

RESULTS

During a follow-up of 8 ± 5.8 years, 96 patients (30%) died due to cardiovascular problems, whereas 13.9% suffered non-fatal CVE. Graft loss occurred in 84 patients (21.6%). Predictors of CVE, survival and graft loss were age and the length of end-stage kidney disease. All scores performed well in assessing the risk for CVE (P < 0.01). Receiver-operating characteristic analysis using the ESC-SCORE, as an example, suggested a cut-off for risk stratification and clinical decisions.

CONCLUSIONS

We found all tested scores were reliable for cardiovascular assessment. We suggest using cardiac scores for risk assessment before KT and then taking further steps according to current guidelines.

Induction immunosuppression agents as risk factors for incident cardiovascular events and mortality after kidney transplantation

Low T cell counts and acute rejection are associated with increased cardiovascular events (CVEs); T cell-depleting agents decrease both. Thus, we aimed to characterize the risk of CVEs by using an induction agent used in kidney transplant recipients. We conducted a secondary data analysis of patients who received a kidney transplant and used Medicare as their primary insurance from 1999 to 2010. Outcomes of interest were incident CVE, all-cause mortality, CVE-related mortality, and a composite outcome of mortality and CVE. Of 47 258 recipients, 29.3% received IL-2 receptor antagonist (IL-2RA), 33.3% received anti-thymocyte globulin (ATG), 7.3% received alemtuzumab, and 30.0% received no induction. Compared with IL-2RA, there was no difference in the risk of CVE in the ATG (adjusted hazard ratio [aHR] 0.98, 95% confidence interval [CI] 0.92-1.05) and alemtuzumab group (aHR 1.01, 95% CI 0.89-1.16), but slightly higher in the no induction group (aHR 1.06, 95% CI 1.00-1.14). Acute rejection did not modify this association in the latter group but did increase CVE by 46% in the alemtuzumab group. There was no difference in the hazard of all-cause or CVE-related mortality. Only in the ATG group, a 7% lower hazard of the composite outcome of mortality and CVE was noted. Induction agents are not associated with incident CVE, although prospective trials are needed to determine a personalized approach to prevention.

Comparing the Predictive Power of Preoperative Risk Assessment Tools to Best Predict Major Adverse Cardiac Events in Kidney Transplant Patients

BACKGROUND

Patients undergoing kidney transplantation have increased risk of adverse cardiovascular events due to histories of hypertension, end-stage renal disease, and dialysis. As such, they are especially in need of accurate preoperative risk assessment.

METHODS

We compared three different risk assessment models for their ability to predict major adverse cardiac events at 30 days and 1 year after transplant. These were the PORT model, the RCRI model, and the Gupta model. We used a method based on generalized U-statistics to determine statistically significant improvements in the area under the receiver operator curve (AUC), based on a common major adverse cardiac event (MACE) definition. For the top-performing model, we added new covariates into multivariable logistic regression in an attempt to create further improvement in the AUC.

RESULTS

The AUCs for MACE at 30 days and 1 year were 0.645 and 0.650 (PORT), 0.633 and 0.661 (RCRI), and finally 0.489 and 0.557 (Gupta), respectively. The PORT model performed significantly better than the Gupta model at 1 year (p=0.039). When the sensitivity was set to 95%, PORT had a significantly higher specificity of 0.227 compared to RCRI's 0.071 (p=0.009) and Gupta's 0.08 (p=0.017). Our additional covariates increased the receiver operator curve from 0.664 to 0.703, but this did not reach statistical significance (p=0.278).

CONCLUSIONS

Of the three calculators, PORT performed best when the sensitivity was set at a clinically relevant level. This is likely due to the unique variables the PORT model uses, which are specific to transplant patients.

Clinical Outcomes of ABO-Incompatible Kidney Transplantation in Patients with End-Stage Kidney Disease due to Diabetes Nephropathy

BACKGROUND

Diabetes nephropathy is one of the most common causes of end-stage kidney disease (ESKD) worldwide. The data are clear that kidney transplantation is superior to remaining on dialysis for patients with diabetes. However, there have been no reports on ABO-incompatible kidney transplantation in patients with ESKD due to diabetes nephropathy.

PATIENTS AND METHODS

We conducted a retrospective, observational study to investigate the clinical outcomes of ABO-incompatible kidney transplantation for patients with pre-existing diabetes nephropathy at our institution from April 2011 to October 2017. A total of 14 recipients were enrolled in this study.

RESULTS

All 14 patients underwent successful kidney transplantation. Both overall patient and graft survival rates were 100, 89.9, and 89.9% at 1, 3, and 5 years, respectively. One patient died 20 months after transplantation with a functioning graft due to pancreas cancer. Two of the 14 patients (14.3%) developed biopsy-proven acute cellular rejection during the follow-up period. The median observation period was 32.0 months (range 5-83 months).

CONCLUSION

ABO-incompatible kidney transplantation may be an acceptable renal replacement therapy for ESKD patients with diabetes.

Incidence and magnitude of post-transplant cardiovascular disease after pediatric kidney transplantation: Risk factor analysis of 1058 pediatric kidney transplants at the university of Minnesota

BACKGROUND

KT recipients have increased the risk of CVD. The incidence of post-transplant CVEs among pediatric recipients has not been well-characterized.

PATIENTS AND METHODS

Between 1963 and 2015, 884 pediatric (age: 0-17 years old) recipients received 1058 KTs at our institution. The cumulative incidence of CVEs was analyzed. Statistical models were used to estimate risk factors for developing post-transplant CVEs.

RESULTS

Overall median patient survival was 33 years (IQR: 18.7-47). A total of 362 CVEs occurred in 161 (18.3%) patients at a median age of 20.5 years. Arrhythmias (18%) were most common. Cumulative risk of post-transplant CVEs was 9% at 10 years, 17% at 20 years, 25% at 30 years, and 36% at 40 years. Development of post-transplant CVEs was associated with increased mortality (HR 2.25 [95% CI 1.61-3.14]); of those who developed a CVE and died, 22/51 (43.1%) died of CVD. Multivariable risk factors for post-transplant CVEs included a history of pretransplant CVD (aHR 1.92 [1.18-3.13] and graft failure (4.57 [3.13-6.67]).

DISCUSSION

A pretransplant history of CVD and a failed graft are significant risk factors for the development of post-transplant CVE. CVD increases the risk of post-transplant death or graft loss.

ANRIL as a genetic marker for cardiovascular events in renal transplant patients - an observational follow-up cohort study

Cardiovascular disease is the leading cause of morbidity and mortality in kidney transplant recipients. Several single-nucleotide polymorphisms (SNPs) in the ANRIL gene pathway have been associated with cardiovascular events (CE). The main objective was to ascertain whether ANRIL (rs10757278) and CARD8 (rs2043211) SNPs could mediate susceptibility to CE. This was an observational follow-up cohort study of renal transplant recipients at Bellvitge University Hospital (Barcelona) from 2000 to 2014. A total of 505 recipients were followed up until achievement of a CE. Patients who did not achieve the endpoint were followed up until graft loss, lost to follow-up or death. Survival analysis was used to ascertain association between genetic markers, clinical data, and outcome. Fifty-three patients suffered a CE after renal transplantation. Results showed a significant association between ANRIL SNP and CE. Homozygous GG for the risk allele showed higher risk for CE than A carriers for the protective allele [HR = 2.93(1.69-5.11), P < 0.0001]. This effect was maintained when it was analyzed in combination with CARD8, suggesting that CARD8 SNP could play a role in the ANRIL mechanism. However, our study does not clarify the molecular mechanism for the CARD8 SNP regulation by ANRIL. ANRIL SNP may predispose to the development of CE after successful kidney transplantation.

Outcomes of living donor kidney transplantation in diabetic patients: age and sex matched comparison with non-diabetic patients

BACKGROUND/AIMS

Kidney transplantation (KT) reportedly provides a significant survival advantage over dialysis in diabetic patients. However, KT outcome in diabetic patients compared with that in non-diabetic patients remains controversial. In addition, owing to recent improvements in the outcomes of KT and management of cardiovascular diseases, it is necessary to analyze outcomes of recently performed KT in diabetic patients.

METHODS

We reviewed all diabetic patients who received living donor KT between January 2008 and December 2011. Each patient was age- and sex-matched with two non-diabetic patients who received living donor KT during the same period. The outcomes of living donor KT were compared between diabetic and non-diabetic patients.

RESULTS

Among 887 patients, 89 diabetic patients were compared with 178 non-diabetic patients. The incidence of acute rejection was not different between the diabetic and non-diabetic patients. Urinary tract infection and other infections as well as cardiovascular events occurred more frequently in diabetic patients. However, diabetes, cardiovascular disease, and infection were not significant risk factors of graft failure. Late rejection (acute rejection after 1 year of transplantation) was the most important risk factor for graft failure after adjusting for diabetes mellitus (DM), human leukocyte antigen mismatch, rejection and infection (hazard ratio, 56.082; 95% confidence interval, 7.169 to 438.702; p < 0.001). Mortality was not significantly different between diabetic and non-diabetic patients (0 vs. 2, p = 0.344 by log-rank test).

CONCLUSIONS

End-stage renal disease patients with DM had favorable outcomes with living donor kidney transplantation.

Interaction of Serum Phosphate with Age as Predictors of Cardiovascular Risk Scores in Stable Renal Transplant Recipients

We calculated rate of changes in the cardiovascular risk calculator for renal transplant recipients (CRCRTR) major adverse cardiac events (MACE) in clinically stable renal transplant recipients (RTRs) to identify covariables that associate with fast cardiovascular (CV) risk progression. CRCRTR-MACE scores were calculated on 139 patients in 2011 and 2014. Score changes above and below median changes in scores were labeled fast or slow CV risk progression. Multivariate analysis (MVA) was performed to identify variables significant to percentage changes in scores. Receiver-operating characteristic (ROC) analysis was performed to define sensitivity and specificity of factors significant to fast score progression. Follow-up was 2.61 (2.02-4.47) years. Slow and fast progressions were present in 50.4 and 49.6% of patients, with a median change of 25.8% (- 92.1 to 1,444.7%). MVA showed percentage changes in age and serum phosphate were the only significant variables impacting fast progression in scores. ROC showed 2011 serum phosphate of 1.15 mmol/L to predict fast progression (area under the curve [AUC] of 0.628, p > 0.0126). Age older than 45 years combined with 2011 serum phosphate above 1.15 mmol/L had a significant AUC of 0.781, p < 0.0010 interleukin (IL)-1A and IL-28A were significant associates with serum phosphate above 1.1 mmol/L in the MVA. Changes in CV risk in RTR over time are highly variable. Serum phosphate, even within upper normal levels, predicts worsening of CV risk scores in stable RTR.

Cardiovascular disease: Risk factors and applicability of a risk model in a Greek cohort of renal transplant recipients

AIM

To investigate the incidence and the determinants of cardiovascular morbidity in Greek renal transplant recipients (RTRs) expressed as major advance cardiac event (MACE) rate.

METHODS

Two hundred and forty-two adult patients with a functioning graft for at least three months and available data that were followed up on the August 31, 2015 at two transplant centers of Western Greece were included in this study. Baseline recipients’ data elements included demographics, clinical characteristics, history of comorbid conditions and laboratory parameters. Follow-up data regarding MACE occurrence were collected retrospectively from the patients’ records and MACE risk score was calculated for each patient.

RESULTS

The mean age was 53 years (63.6% males) and 47 patients (19.4%) had a pre-existing cardiovascular disease (CVD) before transplantation. The mean estimated glomerular filtration rate was 52 ± 17 mL/min per 1.73 m². During follow-up 36 patients (14.9%) suffered a MACE with a median time to MACE 5 years (interquartile range: 2.2-10 years). Recipients with a MACE compared to recipients without a MACE had a significantly higher mean age (59 years vs 52 years, P < 0.001) and a higher prevalence of pre-existing CVD (44.4% vs 15%, P < 0.001). The 7-year predicted mean risk for MACE was 14.6% ± 12.5% overall. In RTRs who experienced a MACE, the predicted risk was 22.3% ± 17.1% and was significantly higher than in RTRs without an event 13.3% ± 11.1% (P = 0.003). The discrimination ability of the model in the Greek database of RTRs was good with an area under the receiver operating characteristics curve of 0.68 (95%CI: 0.58-0.78).

CONCLUSION

In this Greek cohort of RTRs, MACE occurred in 14.9% of the patients, pre-existing CVD was the main risk factor, while MACE risk model was proved a dependable utility in predicting CVD post RT.

Cardiovascular Risk Evaluated With the Use of Heartscore in Kidney Transplant Recipients-Three Years of Follow-up

BACKGROUND

Cardiovascular (CV) complications are the major cause of death in kidney transplant (KT) patients.

METHODS

During a 3-year follow-up, 112 KT recipients, from living (LD KTRs; n = 54), and deceased (DD KTRs; n = 58) donors, were assessed for 10-year risk of fatal CV events with the use of the Heartscore tool (www.heartscore.org). In post-KT months 6, 12, and 36, current and optimum (target) CV risks (CVRs) were estimated.

RESULTS

Current risk was lower in the LD KTRs and remained stable. In DD KTRs, the risk was at the highest level in months 6 and 12 of follow-up and decreased in month 36. Change in CVR, ie, the difference between the current and target risk, was the highest in DD KTRs in month 36 of follow-up (P = .014). In the increased-CVR group, recipients were older (P < .01), primarily male (P = .08), and more frequently smokers (P < .01) and had a higher systolic blood pressure (P < .05) despite taking more hypotensive medicines (P < .01), and had higher total cholesterol (P < .01) and low-density lipoprotein (P < .01) levels. In this group, body mass index (BMI) was higher (P < .01) and metabolic syndrome was diagnosed significantly more often (P < .01). The high-risk group (estimated CVR, ≥5) was different also in longer durations of pre-transplantation dialysis (P < .05) and higher rates of CV episodes before transplantation (P < .05). In logistic regression, higher BMI and lower estimated glomerular filtration rate (eGFR) were the parameters strongly correlated with higher CVR.

CONCLUSIONS

Mean CVR applicable to all kidney transplant recipients was stable throughout the follow-up. Changes in the risk affected mainly DD KTRs. In months 6 and 12, CVR was the highest in this group and was substantially reduced in the 3rd year of follow-up, probably owing to medical interventions. In the high-CVR group, impaired function of the transplanted kidney was recorded. CVR scores in patients with renal conditions and after kidney transplantation should additionally account for eGFR.

The ABCs of Immunosuppression: A Primer for Primary Care Physicians

Immunosuppression use for prevention of allograft recognition/rejection has evolved to reflect an expanded understanding of the immune system, as well as a fine tuning of the goals of therapy. Immunosuppression in organ transplantation represents a balance between the desire to improve the health status of an individual affected by chronic conditions versus not imposing an unintended immunodeficiency leading to iatrogenic morbidity/mortality. This article discusses the selection and general dosing of immunosuppression in organ allograft recipients to allow providers to be comfortable in monitoring immunosuppressive therapy long term and the associated, expected posttransplant complications in allograft recipients.

Interferon-γ-mediated allograft rejection exacerbates cardiovascular disease of hyperlipidemic murine transplant recipients

RATIONALE

Transplantation, the most effective therapy for end-stage organ failure, is markedly limited by early-onset cardiovascular disease (CVD) and premature death of the host. The mechanistic basis of this increased CVD is not fully explained by known risk factors.

OBJECTIVE

To investigate the role of alloimmune responses in promoting CVD of organ transplant recipients.

METHODS AND RESULTS

We established an animal model of graft-exacerbated host CVD by combining murine models of atherosclerosis (apolipoprotein E-deficient recipients on standard diet) and of intra-abdominal graft rejection (heterotopic cardiac transplantation without immunosuppression). CVD was absent in normolipidemic hosts receiving allogeneic grafts and varied in severity among hyperlipidemic grafted hosts according to recipient-donor genetic disparities, most strikingly across an isolated major histocompatibility complex class II antigen barrier. Host disease manifested as increased atherosclerosis of the aorta that also involved the native coronary arteries and new findings of decreased cardiac contractility, ventricular dilatation, and diminished aortic compliance. Exacerbated CVD was accompanied by greater levels of circulating cytokines, especially interferon-γ and other Th1-type cytokines, and showed both systemic and intralesional activation of leukocytes, particularly T-helper cells. Serological neutralization of interferon-γ after allotransplantation prevented graft-related atherosclerosis, cardiomyopathy, and aortic stiffening in the host.

CONCLUSIONS

Our study reveals that sustained activation of the immune system because of chronic allorecognition exacerbates the atherogenic diathesis of hyperlipidemia and results in de novo cardiovascular dysfunction in organ transplant recipients.

Cardiovascular Screening and Management Among Kidney Transplant Candidates in Hungary

INTRODUCTION

Cardiovascular disease is a major cause of morbidity and mortality in end-stage renal disease patients on dialysis and the most common cause of death in the immediate post-transplantation period. The aim of our study was to describe a novel approach of cardiovascular screening and management of dialysis patients evaluated for the transplant waiting list.

METHODS

Twenty-eight patients with end-stage renal disease put on the waiting list between July 2013 and July 2014 were subjected to a prespecified cardiovascular screening protocol utilizing noninvasive and/or invasive tests. Patients were subsequently divided into 3 strata in terms of their estimated cardiovascular risk. Each of these groups were then prescribed interventions aiming to improve their cardiovascular condition.

RESULTS

According to our prespecified protocol of cardiovascular screening studies, 15 (54%) patients were identified as low, 5 (18%) as intermediate, and 8 (28%) as high risk. Four (14%) patients were current smokers. In the low-risk group, we initiated a patient education program involving counseling on regular exercise such as swimming or cycling to improve their functional capacity. In the high-risk group revascularization was done in 5 cases (63%), including 3 percutaneous transluminal coronary angioplasties (PTCA) with stents for single-vessel disease, and coronary artery bypass graft surgeries (CABG) for triple-vessel disease in 2 cases. In the medium-risk group medical management was opted for, including introduction of beta-blockers, inhibitors, statins, and ezetimibe, as well as efforts to optimize anemia management, indices of bone-mineral disease, and fluid status.

CONCLUSION

In our regional transplant program, we introduced a comprehensive multidisciplinary approach to treat potential transplant candidates according to cardiovascular risk stratification based on a prespecified screening protocol. Further studies are needed to correlate this novel strategy with post-transplantation outcomes.

Cardiovascular risk 10 years after liver transplant

OBJECTIVES

We sought to evaluate the frequency of cardiovascular risk factors in a cohort of patients 10 years after a liver transplant, and to assess their 10-year risk of fatal cardiovascular disease using Systematic COronary Risk Evaluation (SCORE) charts.

MATERIALS AND METHODS

Between January 1990 and June 1996, one hundred eighty-nine adults underwent a first liver transplant in our center. Fifty-nine patients (31%) died before reaching their tenth year, and 115 patients were available with complete clinical data at 10 years.

RESULTS

The main indications for liver transplant were alcoholic (38%) and viral cirrhosis (40%). The median age of patients was 56 (range, 29-73 y), 80% were men, 23% were obese, 16% were active smokers, 18% were diabetic, 40% had hypercholesterolemia, and 77% had hypertension. Before the tenth year after transplant, 6 deaths were because of cardiovascular diseases, which represents the third cause of late death (> 1 year after liver transplant). After liver transplant, 5% of the surviving patients underwent ischemic cardiovascular events during the first decade. At a 10-year assessment, the median estimated 10-year risk of fatal cardiovascular disease was 1% (range, 0%-9%) and 10% of the patients had a high risk (ie, SCORE ≥ 5%).

CONCLUSIONS

Our results suggest that the frequency of cardiovascular events is relatively low after a liver transplant, even if most of the patients had 1 or more cardiovascular risk factors. Nevertheless, clinicians should perform a similar evaluation 15 or 20 years after the liver transplant because cardiovascular risk exponentially increases with age.

Incidence, risk factors, and outcomes of stroke post-transplantation in patients receiving a steroid sparing immunosuppression protocol

Corticosteroid use after transplantation is associated with an increased incidence of cardiovascular events and death. Cerebrovascular disease is a common cause of morbidity and mortality post-renal transplantation; however, a dedicated analysis of cerebrovascular disease in recipients of a steroid sparing protocol has not been reported. The aim of this study was to examine the incidence, risk factors, and outcomes of CVA in transplant recipients receiving a steroid sparing protocol. We retrospectively analyzed 1237 patients who received a kidney alone or a simultaneous pancreas and kidney (SPK) transplant. Fifty-six of 1237 (4.53%) patients had a CVA post-transplant. All-cause mortality was significantly higher in the CVA group compared with the non-CVA group, OR: 3.4 (1.7-7.0), p < 0.001. Factors found to be associated with increased risk of CVA by multivariate analysis were older age, HR: 1.07 (1.04-1.09), p < 0.001; diabetes at the time of transplantation, HR: 2.83 (1.42-5.64), p = 0.003; corticosteroid use pre-transplant, HR: 3.27 (1.29-8.27), p = 0.013 and recipients of a SPK, HR: 4.03 (1.85-8.79), p < 0.001. This study has identified subgroups of patients who are at increased risk of CVA post-transplant in patients otherwise receiving a steroid sparing immunosuppression protocol.

Contribution of impaired renal function to cardiovascular risk prediction models in renal transplant recipients

BACKGROUND

The Framingham risk score (FRS) and cardiovascular risk calculator for renal transplant recipients (CRCRTR-MACE) quantify cardiovascular risk in renal transplant recipients (RTR). In contrast to the FRS, the CRCRTR-MACE includes serum creatinine as a variable in the risk prediction equation.

OBJECTIVE

To determine the influence of impaired renal function on performances of the two equations.

METHODS

A chart review of 270 RTR transplanted from 1979 to 2012. High risk was defined at scores ≥20%. Standard statistical analyses included multivariate analysis (MVA), stepwise analysis, and odds ratio to estimate contributions of risk factors.

RESULTS

Mean transplant duration was 9.51 ± 6.65 yr. Mean eGFR was 59.19 ± 28.26 mL/min/1.73 m(2) . FRS and CRCRTR-MACE scores of least 20% were present in 9.3% and 24.8%, respectively, while 7.2% and 11.2% of RTR with eGFR ≥60 mL/min/1.73 m(2) were high risk, respectively. Mean age, blood pressure, TC:HDL ratio, smoking, and diabetes were evenly distributed in patients with varying eGFR. FRS scores remained similar at wide eGFR range (≤30 mL/min/1.73 m(2) -≥90 mL/min/1.73 m(2) ), while CRCRTR-MACE scores significantly increased as eGFR decreased.

CONCLUSIONS

CRCRTR-MACE identified more patients at high cardiovascular risk, even in those with more favorable renal function, suggesting a fundamental difference between the two calculators beyond renal function.

Cardiovascular risk assessment in kidney transplantation

Cardiovascular disease (CVD) remains the most common cause of death after kidney transplantation worldwide, with the highest event rate in the early postoperative period. In an attempt to address this issue, screening for CVD prior to transplant is common, but the clinical utility of screening asymptomatic transplant candidates remains unclear. A large degree of variation exists among both transplant center practice patterns and clinical practice guidelines regarding who should be screened, and opinions are based on mixed observational data with great potential for bias. In this review, we discuss the potential risks, benefits, and evidence for screening for CVD in kidney transplant candidates, and also the next steps to better evaluate and treat asymptomatic kidney transplant candidates.

Metabolic syndrome definitions and components in predicting major adverse cardiovascular events after kidney transplantation

Metabolic syndrome (MetS) associates with cardiovascular risk post-kidney transplantation, but its ambiguity impairs understanding of its diagnostic utility relative to components. We compared five MetS definitions and the predictive value of constituent components of significant definitions for major adverse cardiovascular events (MACE) in a cohort of 1182 kidney transplant recipients. MetS definitions were adjusted for noncomponent traditional Framingham risk factors and relevant transplant-related variables. Kaplan-Meier, logistic regression, and Cox proportional hazards analysis were utilized. There were 143 MACE over 7447 patient-years of follow-up. Only the World Health Organization (WHO) 1998 definition predicted MACE (25.3 vs 15.5 events/1000 patient-years, P = 0.019). Time-to-MACE was 5.5 ± 3.5 years with MetS and 6.8 ± 3.9 years without MetS (P < 0.0001). MetS was independent of pertinent MACE risk factors except age and previous cardiac disease. Among MetS components, dysglycemia provided greatest hazard ratio (HR) for MACE (1.814 [95% confidence interval 1.26-2.60]), increased successively by microalbuminuria (HR 1.946 [1.37-2.75]), dyslipidemia (3.284 [1.72-6.26]), hypertension (4.127 [2.16-7.86]), and central obesity (4.282 [2.09-8.76]). MetS did not affect graft survival. In summary, although the WHO 1998 definition provides greatest predictive value for post-transplant MACE, most of this is conferred by dysglycemia and is overshadowed by age and previous cardiac disease.

Validity of cardiovascular risk prediction models in kidney transplant recipients

Background. Predicting cardiovascular risk is of great interest in renal transplant recipients since cardiovascular disease is the leading cause of mortality. Objective. To conduct a systematic review to assess the validity of cardiovascular risk prediction models in this population. Methods. Five databases were searched (MEDLINE, EMBASE, SCOPUS, CINAHL, and Web of Science) and cohort studies with at least one year of follow-up were included. Variables that described population characteristics, study design, and prognostic performance were extracted. The Quality in Prognostic Studies (QUIPS) tool was used to evaluate bias. Results. Seven studies met the criteria for inclusion, of which, five investigated the Framingham risk score and three used a transplant-specific model. Sample sizes ranged from 344 to 23,575, and three studies lacked sufficient event rates to confidently reach conclusion. Four studies reported discrimination (as measured by c-statistic), which ranged from 0.701 to 0.75, while only one risk model was both internally and externally validated. Conclusion. The Framingham has underestimated cardiovascular events in renal transplant recipients, but these studies have not been robust. A risk prediction model has been externally validated at least on one occasion, but comprehensive validation in multiple cohorts and impact analysis are recommended before widespread clinical application is advocated.

Evidence of enhanced systemic inflammation in stable kidney transplant recipients with low Framingham risk scores

BACKGROUND

While the Framingham risk score (FRS) predicts cardiovascular risk in the general population, it underestimates cardiovascular events in renal transplant recipients (RTR). Inflammation is common in RTR, and it is also a hallmark of vascular injury contributing to cardiovascular events.

OBJECTIVE

To explore the relationship between inflammatory chemokines (CCL family) and FRS in a stable RTR.

METHODS

The modified FRS (2009) was used to calculate the 10-yr probability of CVE in 150 RTR. A cross-sectional study measured plasma levels of 14 CCLs by Luminex technique in 53% (79/150) of the cohort and 28 controls.

RESULTS

43.3% of RTR was classified as low, 16% moderate, and 40.7% high FRS. FRS correlated with eGFR and all CCLs with R of <0.2(p = n.s). Compared with controls, CCL 1,4,8,15, and 27 were equally increased in both the high and low FRS groups (p < 0.04 and 0.03, respectively). The percentage of patients with low FRS and CCL 8,15, and 27 values above the 95% cutoff control levels was 46.1%, 76.9%, and 53.8%, respectively.

CONCLUSIONS

Over one half of stable RTR, including those with low FRS, have increased inflammatory chemokine levels. Inflammation is not accounted for in the FRS, and this may explain the poor performance of FRS in transplant patients.

Cardiovascular risk estimated in renal transplant recipients with the Framingham score

BACKGROUND

Cardiovascular disease is responsible for much of the mortality and morbidity observed in the renal transplant population. Some studies have applied the Framingham score mainly to the chronic kidney disease (CKD) on renal replacement therapy in an attempt to predict cardiovascular events, but the results underestimated the risk. It became evident at the participation of so-called nontraditional factors, such as anemia and inflammatory markers among others, were important predictors of risk in this population.

OBJECTIVE

The aim of this study was to apply the Framingham score to a population of renal transplant subjects to assess its quality to predict cardiovascular events among a population without the theoretically nontraditional risk factors.

METHODS

We retrospectively evaluated the medical records of patients transplanted from 2005 to 2010 for the score as determined by sex, age, blood pressure, low-density lipoprotein cholesterol, smoking history, and presence of diabetes mellitus. The final results expressed the risk for absolute development of cardiovascular diseases at the end of 10 years.

RESULTS

Among 126 patients including 44 women and, 82 men of mean age 45 ± 16 years were 64 living-related and 62 deceased-donor grafts. The etiology of CKD was hypertension (58%), diabetes (37%), and other causes (5%). Fifty-nine percent of patients had a low risk of developing coronary artery diseases at the end of 10 years, 30% medium risk, and only 11% high risk when measured by the Framingham score.

CONCLUSIONS

The assessment of cardiovascular risk using the Framingham risk score did not reflect the observations in the literature of both high mortality and high morbidity. Therefore, this was not a good method to assess the risk of cardiovascular disease, probably because it does not include cardiovascular risk factors in addition to traditional ones that are important in this population.

Associations of ABCB1 and IL-10 genetic polymorphisms with sirolimus-induced dyslipidemia in renal transplant recipients

BACKGROUND

Hyperlipidemia is a common adverse effect of sirolimus (SRL). We previously showed significant associations of ABCB1 3435C>T and IL-10 -1082G>A with log-transformed SRL dose-adjusted weighted-normalized trough. We further examined to see whether these polymorphisms were also associated with SRL-induced dyslipidemia.

METHODS

Genotyping was performed for ABCB1 1236C>T, 2677 G>T/A, and 3435C>T; CYP3A4 -392A>G; CYP3A5 6986A>G and 14690G>A; IL-10 -1082G>A; TNF -308G>A; and ApoE ε2, ε3, and ε4 alleles. The longitudinal changes of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels after SRL treatment before statin therapy were analyzed by a linear mixed-effects model, with adjustments for selected covariates for each lipid.

RESULTS

Under the dominant genetic model, ABCB1 3435C>T was associated with TC (P=0.0001) and LDL-C (P<0.0001) values after SRL administration. Mean TC and LDL-C levels were 26.9 and 24.9 mg/dL higher, respectively, in ABCB1 3435T carriers than 3435CC homozygotes at an average SRL trough concentration of 4 ng/mL without concomitant medication. ABCB1 1236C>T under the recessive model and IL-10 -1082G>A under the dominant model were associated with log-transformed TG values (P=0.0051 and 0.0436, respectively). Mean TG value was 25.1% higher in ABCB1 1236TT homozygotes compared with ABCB1 1236C carriers and was 12.4% higher in IL-10 -1082AA homozygotes than -1082G carriers.

CONCLUSIONS

ABCB1 polymorphisms were found to be associated with lipid responses to SRL treatment, confirming the role of ABCB1 gene in SRL pharmacokinetics and pharmacodynamics. Further studies are necessary to define the role of ABCB1 and IL-10 polymorphisms on SRL-induced dyslipidemia in renal transplantation.

Diabetes and kidney transplantation: past, present, and future

Diabetes mellitus is the most common etiology for end stage renal disease (ESRD) worldwide and in the United States. The incidence of morbidity and mortality is higher in diabetic patients with ESRD due to increased cardiovascular events. Patients with type 2 diabetes who receive a renal allograft have a higher survival rate compared with patients who are maintained on chronic hemodialysis therapy, but there is scarcity of data on long-term graft outcomes. Most recently the development of new onset diabetes after transplantation (NODAT) poses a serious threat to patient and allograft survival. Pre-emptive transplantation and the use of living donors have improved overall survival. In addition, critical management of glucose, blood pressure, and cholesterol are some of the factors that can help minimize adverse outcomes in both patients with pre-existing diabetes and patients who develop NODAT. Future clinical trials are warranted to improve therapeutic medical management of these patients thus influencing graft attrition.

A cardiovascular risk calculator for renal transplant recipients

BACKGROUND

Renal transplant recipients (RTRs) have increased cardiovascular disease (CVD) risk. Standard CVD risk calculators are poorly predictive in RTRs; we therefore aimed to develop and validate an equation for CVD risk prediction in this population.

METHODS

We used data from the Assessment of Lescol in Renal Transplantation trial, which are randomly divided into an assessment sample and a test sample (67% and 33%, respectively, of the total population). For variable selection in the assessment sample, backward stepwise Cox regression was used. Using the regression coefficients and centralized prognostic index, risk was calculated for individual patients. The equation was then validated for calibration and discrimination using the test sample.

RESULTS

Major adverse cardiac events could be predicted using a seven-variable model including age, previous coronary heart disease, diabetes, low-density lipoprotein, creatinine, number of transplants, and smoking. The calibration of the model was good in the test sample with a Hosmer-Lemeshow chi-square value of 11.47 and a P value of 0.245. The areas under the receiver operating characteristic curve were 0.738 in the assessment sample and 0.740 in the test sample. Total mortality could be predicted using a six-variable model including age, coronary heart disease, diabetes, creatinine, total time on renal replacement therapy, and smoking. The calibration of the model was acceptable in the test sample with a Hosmer-Lemeshow chi-square value of 13.08 and a P value of 0.109. The areas under the receiver operating characteristic curve were 0.734 in the assessment sample and 0.720 in the test sample.

CONCLUSIONS

Using the Assessment of Lescol in Renal Transplantation trial population, a formula for 7-year CVD and mortality risk calculation for prevalent RTRs has been developed.

Framingham risk score and novel cardiovascular risk factors underpredict major adverse cardiac events in kidney transplant recipients

BACKGROUND

Framingham Risk Score (FRS) is an insufficient cardiovascular event predictor in unselected kidney transplant recipients. Its role in different risk subgroups and the value of adding novel risk factor candidates to FRS is unknown.

METHODS

We reviewed patients who underwent transplantation from 1998 to 2008 with minimum 3 months graft function, determining FRS-ascertained 10-year risk at 3 months along with relevant clinical and laboratory information. Major adverse cardiac events (MACE) (myocardial infarction, coronary artery revascularization, or cardiac death) 3 months posttransplant were captured. Time-to-MACE multivariate Cox modeling with FRS and novel risk factors (C-reactive protein, uric acid, urine albumin-to-creatinine ratio) as independent variables was performed.

RESULTS

Of 956 patients, 89 experienced MACE (2.17 events/100 patient-years). FRS-predicted 10-year risk was 14.7% ± 10.0% in males with and 9.2% ± 8.2% in those without subsequent MACE (P < 0.0001), although FRS substantially underestimated MACE (actual-to-predicted event ratio 1.2-8.4 in different subgroups, all P < 0.0001). Although patients with MACE had a higher C-reactive protein (5.4 ± 6.0 vs. 3.8 ± 2.5 mg/L, P = 0.026) and uric acid (417 ± 109 vs. 386 ± 101 μmol/L, P = 0.012) level as well as lower 3-month estimated glomerular filtration rate (50.1 ± 20.1 vs. 54.8 ± 18.3 mL/min/1.73 m(2), P = 0.022), only FRS more than or equal to 10% (hazard ratio 2.313, 95% confidence interval 1.49-3.58, P = 0.0002) and estimated glomerular filtration rate less than 50 mL/min/1.73 m(2) (hazard ratio 2.291, 95% confidence interval 1.06-4.94, P = 0.034) predicted MACE in multivariate analysis. Adding novel risk factors to FRS did not improve FRS prediction.

CONCLUSION

FRS substantially underpredicts MACE in kidney transplant recipients among all risk subgroups. Commonly available novel risk factors do not improve FRS predictive value.

Incidence of cardiovascular events after kidney transplantation and cardiovascular risk scores: study protocol

Background

Cardiovascular disease (CVD) is the major cause of death after renal transplantation. Not only conventional CVD risk factors, but also transplant-specific risk factors can influence the development of CVD in kidney transplant recipients.

The main objective of this study will be to determine the incidence of post-transplant CVD after renal transplantation and related factors. A secondary objective will be to examine the ability of standard cardiovascular risk scores (Framingham, Regicor, SCORE, and DORICA) to predict post-transplantation cardiovascular events in renal transplant recipients, and to develop a new score for predicting the risk of CVD after kidney transplantation.

Methods/Design

Observational prospective cohort study of all kidney transplant recipients in the A Coruña Hospital (Spain) in the period 1981-2008 (2059 transplants corresponding to 1794 patients).

The variables included will be: donor and recipient characteristics, chronic kidney disease-related risk factors, pre-transplant and post-transplant cardiovascular risk factors, routine biochemistry, and immunosuppressive, antihypertensive and lipid-lowering treatment. The events studied in the follow-up will be: patient and graft survival, acute rejection episodes and cardiovascular events (myocardial infarction, invasive coronary artery therapy, cerebral vascular events, new-onset angina, congestive heart failure, rhythm disturbances and peripheral vascular disease).

Four cardiovascular risk scores were calculated at the time of transplantation: the Framingham score, the European Systematic Coronary Risk Evaluation (SCORE) equation, and the REGICOR (Registre Gironí del COR (Gerona Heart Registry)), and DORICA (Dyslipidemia, Obesity, and Cardiovascular Risk) functions.

The cumulative incidence of cardiovascular events will be analyzed by competing risk survival methods. The clinical relevance of different variables will be calculated using the ARR (Absolute Risk Reduction), RRR (Relative Risk Reduction) and NNT (Number Needed to Treat).

The ability of different cardiovascular risk scores to predict cardiovascular events will be analyzed by using the c index and the area under ROC curves. Based on the competing risks analysis, a nomogram to predict the probability of cardiovascular events after kidney transplantation will be developed.

Discussion

This study will make it possible to determine the post-transplant incidence of cardiovascular events in a large cohort of renal transplant recipients in Spain, to confirm the relationship between traditional and transplant-specific cardiovascular risk factors and CVD, and to develop a score to predict the risk of CVD in these patients.

Immunosuppression with belatacept-based, corticosteroid-avoiding regimens in de novo kidney transplant recipients

Current immunosuppressive regimens in renal transplantation typically include calcineurin inhibitors (CNIs) and corticosteroids, both of which have toxicities that can impair recipient and allograft health. This 1-year, randomized, controlled, open-label, exploratory study assessed two belatacept-based regimens compared to a tacrolimus (TAC)-based, steroid-avoiding regimen. Recipients of living and deceased donor renal allografts were randomized 1:1:1 to receive belatacept-mycophenolate mofetil (MMF), belatacept-sirolimus (SRL), or TAC-MMF. All patients received induction with 4 doses of Thymoglobulin (6 mg/kg maximum) and an associated short course of corticosteroids. Eighty-nine patients were randomized and transplanted. Acute rejection occurred in 4, 1 and 1 patient in the belatacept-MMF, belatacept-SRL and TAC-MMF groups, respectively, by Month 6; most acute rejection occurred in the first 3 months. More than two-thirds of patients in the belatacept groups remained on CNI- and steroid-free regimens at 12 months and the calculated glomerular filtration rate was 8-10 mL/min higher with either belatacept regimen than with TAC-MMF. Overall safety was comparable between groups. In conclusion, primary immunosuppression with belatacept may enable the simultaneous avoidance of both CNIs and corticosteroids in recipients of living and deceased standard criteria donor kidneys, with acceptable rates of acute rejection and improved renal function relative to a TAC-based regimen.

Cardiac evaluation prior to kidney transplantation

Kidney transplantation is the treatment of choice for most patients with stage 5 chronic kidney disease and end-stage renal disease (ESRD), offering improved quality of life and overall survival rates. However, the limited supply of available organs makes this a scarce resource. Cardiovascular complications continue to be the leading cause of mortality in the kidney transplant population, accounting for over 30% of deaths with a functioning allograft. Thus, preoperative cardiac risk assessment is critical to optimize patient selection and outcomes. Currently there is no consensus for cardiovascular evaluation in the chronic kidney disease and ESRD population prior to kidney transplantation; the recommendations of the American Society of Nephrology and American Society of Transplantation differ from those of the American Heart Association and the American College of Cardiology. Previously developed risk scores have also been used to risk stratify this population. In this review, we discuss two cases that illustrate the difficulties of interpreting the prognostic value of current testing strategies. We also discuss the importance of different tests for cardiovascular evaluation as well as previous nonkidney transplant specific risk scores used in the pre-kidney transplant population.

Cardiovascular disease in kidney transplant recipients: the prognostic value of inflammatory cytokine genotypes

BACKGROUND

Cardiovascular disease (CVD) represents the main cause of morbidity and mortality after renal transplantation. In view of the modern paradigm of atherosclerosis as an inflammatory disease, this study investigated the impact of inflammatory cytokine polymorphisms on posttransplant CVD.

METHODS

The association between cytokine polymorphisms and CVD was assessed in a case-control study to identify the differences in genotype distributions between kidney allografts with or without posttransplant CVD. To validate our results in two independent groups, we divided a cohort of 798 renal transplant recipients according to geographic area: an evaluation cohort of 478 patients from Emilia-Romagna and a validation cohort of 320 patients from the rest of Italy. Tumor necrosis factor (TNF)-alpha, transforming growth factor-beta1, interleukin (IL)-10, IL-6, interferon-gamma, and IL-8 polymorphisms were analyzed, and thereafter, the cytokine production genotype was assigned.

RESULTS

In the evaluation cohort, the patients in the CVD and no-CVD groups differed significantly in TNF-alpha and IL-10 genotype frequencies. Using multivariate analyses to test the association with CVD, the TNF-alpha high-producer genotype was associated with a significantly increased cardiovascular risk (odds ratio [OR]=4.41, 95% confidence interval (CI)=2.53-7.67). Conversely, the IL-10 high-producer genotype resulted protective against CVD (OR=0.07, 95% CI=0.02-0.29). These findings were confirmed in the validation cohort where the carriers of the TNF-alpha high-producer genotype proved to be at 2.45-fold increased cardiovascular risk (OR=2.45, 95% CI=1.29-4.63), whereas the IL-10 high-producer genotype was associated with a 0.08-fold reduced risk (OR=0.08, 95% CI=0.02-0.36).

CONCLUSIONS

This work suggests a prognostic value of TNF-alpha and IL-10 genotypes, which might represent cardiovascular risk markers in renal transplant.

Transplantation in diabetic kidney failure patients: modalities, outcomes, and clinical management

Diabetes mellitus (DM) is a common and devastating disease, affecting up to 19.3 million Americans. It is the leading cause of chronic kidney disease (CKD) and end-stage renal disease (ESRD) in the United States. Diabetic patients with ESRD have a high incidence of cardiovascular disease and death. For those kidney transplant patients with no history of DM prior to transplantation, the development of new onset diabetes after transplantation (NODAT) also poses a serious threat to both graft and patient survival. Kidney transplantation is the best renal replacement option for diabetic ESRD and has the potential to halt the progression of cardiovascular diseases. Early referral for transplant evaluation is essential for pre-emptive or early kidney transplantation in this cohort of patients. In type 1 DM patients with ESRD, simultaneous pancreas and kidney transplantation (SPK) should be encouraged; and in patients facing prolonged waiting time for SPK transplantation but with an available living donor, living donor kidney transplantation followed by pancreas after kidney transplantation (PAK) is a suitable alternative. Islet transplantation in type 1 diabetics is deemed experimental by Medicare, and easy access to this modality remains restricted to qualified patients enrolled in clinical trials or with private insurance. The optimal management of kidney transplant patients with pre-existent DM or NODAT involves a multi-pronged approach consisting of pharmacological and nonpharmacological intervention to address all potential cardiovascular risk factors such as glycemic and lipid control, blood pressure control, weight loss, and smoking cessation. Finally, re-transplantation should be recommended in suitable kidney transplant patients when the kidney allograft demonstrates continuous and progressive decline in function.

Immunosuppressive drugs in kidney transplantation: impact on patient survival, and incidence of cardiovascular disease, malignancy and infection

Renal transplant recipients have increased mortality rates when compared with the general population. The new immunosuppressive drugs have improved short-term patient survival up to 95% at 1-2 years, but these data have to be confirmed in long-term follow-up. Furthermore, no particular regimen has proved to be superior over others with regard to patient survival. Cardiovascular diseases are the most common cause of mortality in renal transplant recipients and while no immunosuppressive drug has been directly associated with cardiovascular events, immunosuppressive drugs have different impacts on traditional risk factors. Corticosteroids and ciclosporin are the agents with the most negative impact on weight gain, blood pressure and lipids. Tacrolimus increases the risk of new-onset diabetes mellitus. Sirolimus and everolimus have the most impact on risk factors for post-transplant hyperlipidaemia. Modifications in immunosuppression could improve the cardiovascular profile but there is little evidence regarding the beneficial effects of these changes on patient outcomes. Malignancies are also an increasing cause of mortality, overtaking cardiovascular disease in some series. Induction therapy, azathioprine and calcineurin inhibitors (CNIs) are probably the immunosuppressive agents most linked with post-transplant malignancies. Mycophenolate mofetil (MMF) has no negative impact on the incidence of malignancies. Target of rapamycin (mTOR) inhibitors have antioncogenic properties and they are associated with a lower incidence of malignancies. In addition, these agents have been recommended for use to decrease the dose or withdrawal of CNIs in patients with malignancies. Infections are still an important cause of morbidity and mortality in renal transplant recipients. Some immunosuppressive agents such as MMF increase the incidence of cytomegalovirus infection and the need for prophylactic measures in risk recipients. The use of potent immunosuppressive therapy has resulted in the appearance of BK virus nephropathy, which progresses to graft failure in a high percentage of patients. Although first associated with tacrolimus and MMF immunosuppression, recent data suggest that BK nephropathy appears with any kind of triple therapy. In conclusion, reducing risk factors for patient death should be a major target to improve outcomes after renal transplantation. Effort should be made to control cardiovascular diseases, malignancies and infections with improved use of immunosuppressive drugs. Preliminary results with belatacept suggest its safety and efficacy, and open new perspectives in the immunosuppression of de novo renal transplant recipients.

KDIGO clinical practice guideline for the care of kidney transplant recipients

The 2009 Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guideline on the monitoring, management, and treatment of kidney transplant recipients is intended to assist the practitioner caring for adults and children after kidney transplantation. The guideline development process followed an evidence-based approach, and management recommendations are based on systematic reviews of relevant treatment trials. Critical appraisal of the quality of the evidence and the strength of recommendations followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach. The guideline makes recommendations for immunosuppression, graft monitoring, as well as prevention and treatment of infection, cardiovascular disease, malignancy, and other complications that are common in kidney transplant recipients, including hematological and bone disorders. Limitations of the evidence, especially on the lack of definitive clinical outcome trials, are discussed and suggestions are provided for future research.

Post-transplant erythrocytosis: a disappearing phenomenon?

BACKGROUND

Erythrocytosis is relatively common post-kidney transplantation and may have adverse consequences. This study examined whether the incidence of erythrocytosis has remained stable over time and explored the impact of this condition on patient outcomes.

METHODS

This was a retrospective single center review of an incidence cohort (transplanted between 1993 and 2005). Predictors of erythrocytosis and hemoglobin levels and subsequent patient and allograft survival were examined.

RESULTS

Erythrocytosis (hemoglobin >170 g/L for >1 month) was observed in 59 of 511 recipients. Erythrocytosis developed in only 8.1% of those transplanted from 1997 to 2005, compared with 18.7% in those transplanted from 1993 to 1996 (p = 0.0005). Independent predictive factors were use of angiotensin converting enzyme inhibitors/angiotensin receptor blockers (ACEi/ARBs) (HR 0.176, 95% CI 0.040-0.71, p = 0.016), male gender (HR 3.72, 95% CI 1.54-9.0, p = 0.003), and mycophenolic acid agents (HR 0.49, 95% CI 0.237-0.99, p = 0.049). Patients with erythrocytosis had superior overall survival (HR for death 0.105, 95% CI 0.014-0.760, p = 0.026) but a trend for worse death censored graft loss (univariate HR 2.06, 95% CI 0.91-4.65, p = 0.084).

CONCLUSIONS

The incidence of erythrocytosis is falling and is likely related to greater ACEi/ARB use and possibly more antiproliferative immunosuppression. Patient survival is excellent in those with erythrocytosis, but long-term graft survival may be compromised.