Prevention of post-transplant cardiovascular disease--report and recommendations of an ad hoc group

Dyslipidemia in Transplant Patients: Which Therapy?

Cardiovascular disease is the most important cause of death worldwide in recent years; an increasing trend is also shown in organ transplant patients subjected to immunosuppressive therapies, in which cardiovascular diseases represent one of the most frequent causes of long-term mortality. This is also linked to immunosuppressant-induced dyslipidemia, which occurs in 27 to 71% of organ transplant recipients. The aim of this review is to clarify the pathophysiological mechanisms underlying dyslipidemia in patients treated with immunosuppressants to identify immunosuppressive therapies which do not cause dyslipidemia or therapeutic pathways effective in reducing hypercholesterolemia, hypertriglyceridemia, or both, without further adverse events.

Outcomes of Percutaneous Coronary Intervention in Patients With Acquired Immunosuppression

There are limited data on the clinical outcomes of percutaneous coronary intervention (PCI) in patients with acquired immunosuppression who are frequently underrepresented in clinical trials. All PCI procedures between October 2015 and December 2018 in the Nationwide Inpatient Sample were retrospectively analyzed, stratified by immunosuppression status. Multivariable logistic regression models were performed to examine (1) the association between immunosuppression status and in-hospital outcomes, expressed as adjusted odds ratio (aOR) with 95% confidence intervals (CIs) and (2) predictors of mortality among patients with severe acquired immunosuppression. In this contemporary analysis of nearly 1.5 million PCI procedures, approximately 4% of patients who underwent PCI had acquired immunosuppression. Of these, chronic steroid use accounted for approximately half of the cohort who underwent PCI who had acquired immunosuppression, with the remainder divided between hematologic cancer, solid organ active malignancy, and metastatic cancer, with the latter group having the highest rates of composite of in-hospital mortality or stroke (9.3%) (mortality 7.5% and acute ischemic stroke 2.4%). In conclusion, immunosuppression was independently associated with increased adjusted odds of adverse clinical outcomes, specifically mortality or stroke (aOR 1.11, 95% CI 1.06 to 1.15, p <0.001) and in-hospital mortality (aOR 1.21, 95% CI 1.13 to 1.29, p <0.001), with outcomes dependent on the cause of immunosuppression.

Potentially Inappropriate Prescriptions in Heart Failure with Reduced Ejection Fraction (PIP-HFrEF)

Heart failure (HF) is a chronic debilitating and potentially life-threatening condition. Heart Failure patients are usually at high risk of polypharmacy and consequently, potentially inappropriate prescribing leading to poor clinical outcomes. Based on the published literature, a comprehensive HF-specific prescribing review tool is compiled to avoid medications that may cause HF or harm HF patients and to optimize the prescribing practice of HF guideline-directed medical therapies. Recommendations are made in line with the last versions of ESC guidelines, ESC position papers, scientific evidence, and experts' opinions.

Development and future deployment of a 5 years allograft survival model for kidney transplantation

AIM

Identifying kidney transplant patients at highest risk for graft loss prior to loss may allow for effective interventions to improve 5 years survival.

METHODS

We performed a 10 years retrospective cohort study of adult kidney transplant recipients (n = 1747). We acquired data from electronic health records, United Network of Organ Sharing, social determinants of health, natural language processing data extraction, and real-time capture of dynamically evolving clinical data obtained within 1 year of transplant; from which we developed a 5 years graft survival model.

RESULTS

Total of 1439 met eligibility; 265 (18.4%) of them experienced graft loss by 5 years. Graft loss patients were characterized by: older age, being African-American, diabetic, unemployed, smokers, having marginal donor kidneys and cardiovascular comorbidities. Predictive dynamic variables included: low mean blood pressure, higher pulse pressures, higher heart rate, anaemia, lower estimated glomerular filtration rate peak, increased tacrolimus variability, rejection and readmissions. This Big Data analysis generated a 5 years graft loss model with an 82% predictive capacity, versus 66% using baseline United Network of Organ Sharing data alone.

CONCLUSION

Our analysis yielded a 5 years graft loss model demonstrating superior predictive capacity compared with United Network of Organ Sharing data alone, allowing post-transplant individualized risk-assessed care prior to transitioning back to community care.

Management of dyslipidemia in adult solid organ transplant recipients

Solid organ transplantation (SOT) has revolutionized treatment of end-stage disease. Improvements in the SOT continuum of care have unmasked a significant burden of cardiovascular disease, manifesting as a leading cause of morbidity and mortality. Although several risk factors for development of post-transplant cardiovascular disease exist, dyslipidemia remains one of the most frequent and modifiable risks. An important contributor to dyslipidemia in SOT recipients is the off-target metabolic effects of immunosuppressive medications, which may alter lipoproteins and their metabolism. Dyslipidemia management is paramount as lipid-lowering therapy with statins has demonstrated reductions in graft vasculopathy, decreased rejection rates, and improved survival. Several nonstatin medication options are available, but data supporting their benefit in the SOT population are minimal, typically extrapolated from studies in the general population. Further compounding dyslipidemia management is the complex interplay of drug interactions between lipid-lowering and immunosuppressant medications, which can result in serious toxicity and/or therapeutic failure.

Evaluation of Posttransplantation Diabetes Mellitus After Liver Transplantation: Assessment of Insulin Administration as a Risk Factor

BACKGROUND

Impaired glucose regulation posttransplantation can affect allograft survival and may lead to the development of posttransplant diabetes mellitus (PTDM).

OBJECTIVES

The primary purpose of this study is to assess the difference in insulin burden between liver transplant patients who develop PTDM and patients who do not.

METHODS

This was a single-center, retrospective study. Adult liver transplant recipients transplanted between January 1, 2005, and August 1, 2013, were included. PTDM was defined as: (1) use of an oral antihyperglycemic agent for ≥30 consecutive days after transplant, (2) use of insulin ≥30 consecutive days after transplant, or (3) hemoglobin A1C≥6.5 any time after transplant.

RESULTS

Of the 114 patients included, 48 (42%) developed PTDM. The average 24-hour insulin requirement on the medical floors was 17.2 ± 14.5 units in the PTDM group and 11.3 ± 12.2 units in the PTDM-free group;P= 0.02. The average blood glucose level on the medical floor was 184.7 ± 31.5 mg/dL in the PTDM group and 169.3 ± 31.4 mg/dL in the PTDM-free group;P= 0.013. Multivariate analysis revealed that experiencing rejection was positively associated with the development of PTDM: adjusted odds ratio (AOR) = 3.237; 95% CI = 1.214-8.633. Basiliximab was negatively associated with the development of PTDM: AOR = 0.182; 95% CI = 0.040-0.836.

CONCLUSION

Univariate analyses suggest that insulin burden is a positive risk factor for the development of PTDM; this association is lost in multivariate analyses. Rejection was a positive predictor, and use of basiliximab was a negative predictor for the development of PTDM.

Association of Extrarenal Adverse Effects of Posttransplant Immunosuppression With Sex and ABCB1 Haplotypes

Extrarenal adverse effects (AEs) associated with calcineurin inhibitor (CNI) and mycophenolic acid (MPA) occur frequently but are unpredictable posttransplant complications. AEs may result from intracellular CNI accumulation and low activity of P-glycoprotein, encoded by the ABCB1 gene. Since ABCB1 single nucleotide polymorphisms (SNPs) and sex influence P-glycoprotein, we investigated haplotypes and extrarenal AEs. A prospective, cross-sectional study evaluated 149 patients receiving tacrolimus and enteric coated mycophenolate sodium or cyclosporine and mycophenolate mofetil. Immunosuppressive AE assessment determined individual and composite gastrointestinal, neurologic, aesthetic, and cumulative AEs. Lipids were quantitated after 12-hour fast. ABCB1 SNPs: c.1236C>T (rs1128503), c.2677G>T/A (rs2032582), and c.3435C>T (rs1045642) were determined with haplotype associations computed using the THESIAS program, and evaluated by immunosuppression, sex and race using multivariate general linear models. Tacrolimus patients exhibited more frequent and higher gastrointestinal AE scores compared with cyclosporine with association to CTT (P = 0.018) and sex (P = 0.01). Aesthetic AE score was 3 times greater for cyclosporine with TTC haplotype (P = 0.005). Females had higher gastrointestinal (P = 0.022), aesthetic (P < 0.001), neurologic (P = 0.022), and cumulative AE ratios (P < 0.001). Total cholesterol (TCHOL), low-density lipoproteins (LDL), and triglycerides were higher with cyclosporine. The TTC haplotype had higher TCHOL (P < 0.001) and LDL (P = 0.005). Higher triglyceride (P = 0.034) and lower high-density lipoproteins (P = 0.057) were associated with TTT with sex-adjusted analysis. ABCB1 haplotypes and sex were associated with extrarenal AEs. Using haplotypes, certain female patients manifested more AEs regardless of CNI. Haplotype testing may identify patients with greater susceptibility to AEs and facilitate CNI individualization.

Safety and efficacy of autologous mesenchymal stromal cells transplantation in patients undergoing living donor kidney transplantation: a pilot study

AIM

This pilot study assesses the safety and feasibility of autologous mesenchymal stromal cell (MSC) transplantation in four patients that underwent living donor renal transplantation, and the effect on the immunophenotype and functionality of peripheral T lymphocytes following transplantation.

METHODS

All patients received low dose ATG induction followed by calcineurin inhibitor-based triple drug maintenance immunosuppression. Autologous MSCs were administered intravenously pre transplant and day 30 post-transplant. Patients were followed up for 6 months. The frequency of regulatory T cells and T cell proliferation was assessed at different time points.

RESULTS

None of the four patients developed any immediate or delayed adverse effects following MSC infusion. All had excellent graft function, and none developed graft dysfunction. Protocol biopsies at 1 and 3 months did not reveal any abnormality. Compared to baseline, there was an increase in the CD4 + CD25+FOXP3+ regulatory T cells and reduction in CD4 T cell proliferation.

CONCLUSION

We conclude that autologous MSCs can be used safely in patients undergoing living donor renal transplantation, lead to expansion of regulatory T cells and decrease in T cell proliferation. Larger randomized trials studies are needed to confirm these findings and evaluate whether this will have any impact on immunosuppressive therapy.

Effect of liver transplantation on glucose levels in patients with prediabetes or type 2 diabetes

BACKGROUND

Liver transplantation (LT) may induce the occurrence of diabetes mellitus. It can be speculated, however, that the LT may have a beneficial effect on glucose metabolism. We therefore conducted a study to examine the changing trends in blood glucose levels before and after LT in patients with prediabetes or type 2 diabetes.

METHODS

In this observational study, we enrolled 47 patients (38 prediabetes and 9 diabetes) who underwent LT. We compared the blood glucose levels between the pre-transplantation (24 months) and the post-transplantation (36 months) periods and analyzed the diverse factors affecting glucose levels.

RESULTS

The glucose regulation worsened and insulin dose increased in patients with diabetes, which was notably seen during the steroid maintenance period. Following steroid withdrawal, however, there was a decrease in the insulin dose in 55.6% of the patients, and 33.3% of the patients converted from insulin to oral agents. Of the patients with prediabetes, 55.3% developed new-onset diabetes after transplantation (NODAT). However, 18.4% achieved a recovery of glucose levels to normal range. Of the 21 NODAT patients, 52.4% achieved a recovery of glucose level to the prediabetes range after steroid withdrawal. There was a significant correlation between the old age and the persistence of NODAT (P < .05).

CONCLUSIONS

LT may have a diverse effect on glycemia, which may lead to changes in glucose control methods. Therefore, glucose metabolism after LT may need to be differentiated by the underlying glucose disturbance status and the time after LT with or without steroid maintenance period.

Early steroid withdrawal regimen prevents new-onset diabetes mellitus in old-age recipients after living donor liver transplantation

BACKGROUND

Steroid use after liver transplantation is known to increase the risk of new-onset diabetes mellitus (NODM). In this study, we tried to identify a patient subgroup who would benefit with regard to NODM by an early steroid withdrawal regimen (ESWR) after living donor liver transplantation (LDLT) METHODS: Among 100 adult LDLT patients, 65 were on a conventional immunosuppressive regimen (CIR), and 35 were on an ESWR. With the ESWR, the steroid was tapered off mostly within 7 days with induction of basiliximab in combination with tacrolimus and mycophenolate mofetil (MMF). The CIR was a combination of tacrolimus and steroid. MMF was added in selected patients. Steroid was tapered off 2-6 months after LT. The presence of NODM was investigated cross-sectionally 6 months after LT.

RESULTS

There was no significant difference in terms of acute cellular rejection, sepsis, or death during follow-up. NODM had developed in 13 patients (13 %). Old recipient age (≥ 55) and pretransplant history of hypertension were significant risk factors for NODM. The type of immunosuppression was the single risk factor for NODM in subgroup of old-age recipients (≥ 55 years) on the CIR (hazard ratio 13.34, p = 0.04).

CONCLUSIONS

ESWR can safely reduce the incidence of NODM after LDLT in old-age recipients. Therefore, ESWR should be considered first in old-age recipients undergoing LDLT.

Incidence and risk factors for new-onset diabetes in living-donor liver transplant recipients

With the increased number of long-term survivors after liver transplantation, new-onset diabetes after transplantation (NODAT) is becoming more significant in patient follow-up. However, the incidence of new-onset diabetes after living-donor liver transplantation (LDLT) has not been well elucidated. The aim of this study was to evaluate the incidence and risk factors for NODAT in adult LDLT recipients at a single center in Japan. A retrospective study was performed on 161 adult patients without diabetes who had been followed up for ≥three months after LDLT. NODAT was defined according to the 2003 American Diabetes Association/World Health Organization guidelines. The recipient-, donor-, operation-, and immunosuppression-associated risk factors for NODAT were assessed. Overall, the incidence of NODAT was 13.7% (22/161) with a mean follow-up of 49.8 months. In a multivariate analysis, the identified risk factors for NODAT were donor liver-to-spleen (L-S) ratio (hazard ratio [HR] = 0.022, 95% confidence interval [CI] = 0.001-0.500, p = 0.017), and steroid pulse therapy for acute rejection (HR = 3.320, 95% CI = 1.365-8.075, p = 0.008). In conclusion, donor L-S ratio and steroid pulse therapy for acute rejection were independent predictors for NODAT in LDLT recipients. These findings can help in screening for NODAT and applying early interventions.

Is liver transplantation a risk factor for cardiovascular disease? A meta-analysis of observational studies

Up to two-thirds of patients develop metabolic syndrome within the first 5 years after orthotopic liver transplantation (OLT). However, data on overall cardiovascular (CV) morbidity and mortality among OLT recipients and particularly those who develop metabolic syndrome remain elusive. A literature search using MEDLINE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and meeting abstracts (along with their bibliographies) was performed to identify studies. Data on ischemic CV events were extracted from each study and were used for pooled analyses. Overall pooled estimates and 95% confidence intervals (CIs) for the incidence of CV events and deaths were obtained with a random effects model. Twelve observational studies reporting CV outcomes for 4792 post-OLT recipients who were followed for 28,783 person-years were included. Pooled estimates showed that the 10-year risk of developing CV events among the post-OLT recipients was 13.6% (95% CI = 9%-8.1%). Pooled estimates from case-control studies showed that the post-OLT group had an approximately 64% greater risk of experiencing CV events than controls (standardized incidence ratio = 1.64, 95% CI = 1.18-2.20). Among OLT recipients, those with metabolic syndrome were approximately 4 times more likely to have a CV event [odds ratio (OR) = 4.01, 95% CI = 1.94-8.32] without any significant increase in all-cause mortality (OR = 1.15, 95% CI = 0.63-2.10). In conclusion, this systematic review suggests that OLT recipients and particularly those with metabolic syndrome have a high risk for CV events. However, the literature is limited and lacks high-quality studies. Future prospective studies are warranted to confirm these findings and determine whether aggressive risk-reduction strategies can attenuate the increased CV risk seen in this population.

Long-term outcome after liver transplantation

Liver transplantation is a life-saving therapy for patients with end-stage liver disease, acute liver failure, and liver tumors. Over the past 4 decades, improvements in surgical techniques, peritransplant intensive care, and immunosuppressive regimens have resulted in significant improvements in short-term survival. Focus has now shifted to addressing long-term complications and improving quality of life in liver recipients. These include adverse effects of immunosuppression; recurrence of the primary liver disease; and management of diabetes, hypertension, dyslipidemia, obesity, metabolic syndrome, cardiovascular disease, renal dysfunction, osteoporosis, and de novo malignancy. Issues such as posttransplant depression, employment, sexual function, fertility, and pregnancy must not be overlooked, as they have a direct impact on the liver recipient's quality of life. This review summarizes the latest data in long-term outcome after liver transplantation.

Metabolic syndrome in liver transplant recipients: prevalence, risk factors, and association with cardiovascular events

Features of metabolic syndrome are not uncommon in patients after liver transplantation. To examine the prevalence and risk factors of posttransplantation metabolic syndrome (PTMS), the files of 252 transplant recipients (mean age, 54.5 ± 2.8 years, 57.9% male) were reviewed for pretransplant and posttransplant clinical and laboratory parameters (mean follow-up, 6.2 ± 4.4 years). Rates of obesity (body mass index >30 kg/m(2) ), hypertriglyceridemia (>150 mg/dL), high-density lipoprotein cholesterol <40 mg/dL (men) or <50 mg/dL (women), hypertension, and diabetes were significantly higher after transplantation than before. Metabolic syndrome was diagnosed in 5.4% of patients before transplantation and 51.9% after. Besides significantly higher rates of the typical metabolic derangements (P < 0.0001), the patients with PTMS were older and heavier than those without PTMS, and they had a higher rate of pretransplant hepatitis C virus infection (P < 0.03) and more posttransplant major vascular and cardiac events (20 events in 15.2% of patients with PTMS versus 6 events in 4.9% of patients without PTMS; P < 0.007). There was no between-group difference in mortality or causes of death (mainly related to recurrent disease, graft failure, and sepsis). Significant independent predictors of PTMS on logistic regression analysis were age (odds ratio [OR] = 1.04), pretransplant nonalcoholic fatty liver disease (OR = 3.4), body mass index (OR = 1.13), diabetes (OR = 5.95), and triglycerides (OR = 1.01). The rate of metabolic syndrome in liver transplant recipients is more than twice that reported for the general population. PTMS is associated with cardiovascular morbidity but not mortality, and it may be predicted by pretransplantation conditions. Prospective studies are required to determine the significance and management of PTMS.

Alternatives to calcineurin inhibition in renal transplantation: belatacept, the first co-stimulation blocker

In the early 1990s, Linsley and colleagues produced a soluble fusion protein, comprising of the extracellular domain of cytotoxic T lymphocyte antigen (CTLA)4 and the human IgG1 Fc domain. Since then, several hundreds of scientific publications have demonstrated that CTLA4–Ig blocks CD28-mediated co-stimulation and suppresses unwanted T cell-mediated responses in animal models of transplantation, autoimmunity and inflammation. In the past two decades, Bristol-Myers Squibb Co. has developed abatacept, a CTLA4–Ig molecule for treating psoriasis and rheumatoid arthritis, and belatacept, a second-generation, higher affinity CTLA4–Ig molecule for use in kidney transplantation. Belatacept represents a new class of transplantation immunosuppressants and potentially offers clinicians a breakthrough therapy to preserve kidney function in the long term and reduce the side effects of current immunosuppressive therapies.

Long-term medical comorbidities and their management: hypertension/cardiovascular disease

1. There is a high prevalence of cardiovascular risk factors in liver transplant recipients. 2. There is a high incidence of premature onset of cardiovascular disease. 3. The choice of calcineurin inhibitor shows no long-term impact. 4. Established cardiovascular risk scores may determine an individual's risk for cardiovascular events. 5. Posttransplant arterial hypertension is a major burden. 6. Strict surveillance guidelines are needed. 7. Threshold levels for arterial blood pressure according to recommendations for high-risk individuals should be applied. 8. Therapeutic lifestyle changes should be encouraged. 9. Escalating pharmacological treatment with respect to renal function is recommended. 10. Alterations of immunosuppression should be considered.

Obesity, hyperlipidemia, and metabolic syndrome

1. Obesity is increasingly common among liver transplantation (LT) recipients and donors. Outcomes following LT for selected patients with class I-III obesity are similar to those for nonobese recipients. In patients who are otherwise satisfactory candidates for LT, a high body mass index, as long as it does not present a technical barrier, should not be considered to be an absolute contraindication to LT. 2. The most common causes of death beyond the first year of LT are, in descending order of frequency, graft failure (especially secondary to hepatitis C virus recurrence), malignancy, cardiovascular disease, infections, and renal failure. Metabolic syndrome is an important risk factor for each of these etiologies of posttransplant death. Posttransplant diabetes, posttransplant hypertension, and an original diagnosis of cryptogenic cirrhosis, which is commonly associated with metabolic syndrome, are all associated with an increased risk of post-LT mortality. Features of metabolic syndrome should be screened for and treated in LT recipients. 3. Because of the physiological mechanism of post-LT hypertension, which includes renal arteriolar constriction secondary to calcineurin inhibition, calcium channel blocking agents are a good pharmacological treatment modality and have been shown to be effective in renal protection in randomized controlled trials of posttransplant hypertension. 4. It is rare for dietary changes and weight reduction to result in normalization of the lipid profile. Statins should thus be initiated early in the course of management of post-LT dyslipidemia. Forty milligrams of simvastatin per day, 40 mg of atorvastatin per day, and 20 mg of pravastatin per day are reasonable starting doses for post-LT hypercholesterolemia. It is important to remember that the effects of statin therapy are additive to those of a controlled diet (eg, a Mediterranean diet rich in omega-3 fatty acids, fruits, vegetables, and dietary fiber). 5. Nonalcoholic steatohepatitis, an increasingly common etiology of cirrhosis and liver failure, recurs commonly after LT and may also arise de novo. Treatment should be directed at managing obesity and complications of metabolic syndrome. Optimal immunosuppression in patients with nonalcoholic steatohepatitis is still evolving but should include steroid minimization.

Long-term management after liver transplantation: primary care physician versus hepatologist

As long-term survival after liver transplantation increases, metabolic complications are becoming increasingly prevalent. Given concerns about which group of providers should be managing liver recipients and how well metabolic complications are managed, we administered a postal survey to 280 transplant hepatologists to determine attitudes, perceptions, and practice patterns in the management of metabolic complications after transplantation. The response rate was 68.2%. There was great variation in patterns of practice across the United States with respect to the number of posttransplant clinics, clinic format, and number of recipients cared for per week. Hepatologists, primary care physicians (PCPs), and surgeons were primarily responsible for the overall care of liver recipients 1 year or more after liver transplantation according to 66%, 24%, and 8% of respondents, respectively. Hepatologists felt that metabolic complications were common, but few strongly agreed that hypertension (33.3%), chronic renal insufficiency (3.8%), diabetes mellitus (8.8%), dyslipidemia (11.1%), and bone disease (12.8%) were well controlled. The majority of hepatologists indicated that ideally PCPs should be managing recipients' hypertension, diabetes mellitus, dyslipidemia, and bone disease (78.8%, 63.1%, 78.3%, and 72.5%), but they felt that in actuality, PCPs were managing these conditions less frequently (45.4%, 51.4%, 44.6%, and 38%). In conclusion, metabolic complications are perceived to be common but not well controlled post-transplant, and most hepatologists feel that PCPs should take a more active role in the management of these complications. Future studies are needed to identify barriers to care in the treatment of metabolic complications post-transplant with the goal of improving long-term morbidity and mortality.

New-onset diabetes mellitus presenting with diabetic ketoacidosis after pediatric liver transplantation

The development of NODM is a common metabolic complication after liver transplantation. Presentation of post-liver transplant diabetes mellitus with DKA is rare especially among pediatric patients. We reported three pediatric patients who presented with DKA after liver transplantation. The underlying diseases leading to transplantation were cryptogenic liver cirrhosis, Wilson disease, and congenital hepatic fibrosis. None of the three patients had a history of diabetes prior to transplantation and all of them were cases of NODM after transplantation. All three patients presented with severe hyperglycemia, significant ketosis, and metabolic acidosis of variable severity. All of them received tacrolimus as one of the immunosuppressant agents. The patients received a liver transplant from a DD. The patients were treated with intravenous insulin injection (0.1 U/kg/h) and recovered from DKA, but one case expired in the intensive care unit because of bacterial sepsis after recovery from DKA. Our experience suggests that PTDM may result in ketoacidosis, and we emphasize the importance of paying more attention to glucose metabolism and risk of diabetes mellitus in patients with immunosuppressive therapy, especially tacrolimus.

Influence of immunosuppression and effect of hepatitis C virus on new onset of diabetes mellitus in liver transplant recipients

INTRODUCTION

New-onset posttransplantation diabetes mellitus (PTDM), with an incidence of 10% to 30%, increased graft and patient morbidity and mortality. Such causal factors as age, obesity, therapy, immunosuppression, and hepatitis C virus (HCV) contribute to this disease.

OBJECTIVE

We sought to determine the incidence of PTDM and impaired fasting glucose (IFG) concentration in transplant recipients to define the causal variables.

MATERIAL AND METHODS

The study included 127 patients. Patients with pretransplantation diabetes and those with less than 6 months of follow-up were excluded. A descriptive observational study to assess the association between PTDM and IFG and the immunosuppression therapy used was performed by monitoring the potential confounding variables of age, obesity, and HCV.

RESULTS

During mean follow-up of 73.7 months (range, 7-120 mo), 93 patients received cyclosporine A (CyA) and 34 received tacrolimus (Tac) therapy. Thirty patients (23.6%) developed PTDM or IFG including 15 (16%; PTDM, six IFG, nine) in the CyA group and 15 (PTDM, seven; IFG, eight) in the Tacrolimus group (P = .001; odds ratio [OR], 4.1). They were homogeneous with respect to confounding variables except for HCV (P = .01). Of the 55 patients with HCV infection, 12 developed PTDM or IFG, including three in the CyA group and nine in the tacrolimus group (P = .03; OR, 7.7), whereas in the 72 patients without HCV infection, the CyA or tacrolimus association with PTDM or IFG was significant (P = .05), Mantel-Haenszel test; OR, 4.9). The interaction between HCV and immunosuppression therapy was primarily produced in the IFG group (HCV-positive; P = .008; OR, 8).

CONCLUSION

We observed an association between the use of tacrolimus and the development of PTDM or IFG. There is greater risk in HCV-positive patients, in particular in relation to IFG. The choice of immunosuppressive treatment might be decided on the basis of the patient's pretransplantation status.

Conversion from cyclosporine to tacrolimus in patients at risk for chronic renal allograft failure: 60-month results of the CRAF Study

BACKGROUND

This study compared the long-term effects of switching from cyclosporine to tacrolimus on the incidence, progression, and severity of chronic renal allograft failure in patients with elevated serum creatinine levels.

METHODS

Patients were assigned randomly (2:1) to switch to tacrolimus or remain on cyclosporine. Tacrolimus was initiated at 1/50th of the cyclosporine dose or 0.15 mg/kg/day, whichever dose was lower, to maintain trough concentrations between 5 and 15 ng/mL. Cyclosporine doses were adjusted to achieve trough concentrations between 100 and 300 ng/mL.

RESULTS

At 60 months, the median change from baseline in serum creatinine was -0.2 mg/dL in the tacrolimus group and 0.3 mg/dL in the cyclosporine group (P=0.003). Median change in estimated creatinine clearance was 1.2 mL/min in the tacrolimus group and -4.1 mL/min in the cyclosporine group (P=0.019). The incidence of new-onset diabetes, hyperglycemia, hypertension, lymphoma, and malignancies was generally low and comparable between groups. Fewer patients in the tacrolimus group than in the cyclosporine group developed new cardiac conditions (11% vs. 28%, P=0.004), had low-density lipoprotein (LDL) cholesterol values more than 130 mg/dL (29% vs. 57%, P=0.002), or developed hyperlipidemia (24% vs. 67%, P=0.046) during the 60-month follow-up period. Despite these changes, patient and graft survival were similar for both groups.

CONCLUSION

Switching from cyclosporine to tacrolimus resulted in improved renal function and a reduction in the occurrence of new-onset cardiac conditions and hyperlipidemia, with no increase in the incidence of new-onset diabetes or new-onset hyperglycemia. However, after 5 years there was no impact on patient or graft survival.

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

BACKGROUND AND OBJECTIVES

Cardiovascular disease is an important cause of morbidity and death in kidney transplant recipients. This study examines the Framingham risk score's ability to predict cardiac and stroke events. Because cyclosporine and tacrolimus have different cardiovascular risk profiles, these agents were also examined.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A prospective cohort evaluation of 540 patients were followed for a median of 4.7 yr in an outpatient kidney transplant clinic. Baseline Framingham risk scores were calculated and all cardiovascular outcomes were collected.

RESULTS

Rates per 100 patient-years were 1.79 for cardiac and 0.78 for stroke events. The ratio of observed-to-predicted cardiac events was 1.64-fold higher [95% confidence interval (CI) 1.19 to 2.94] for the cohort, 2.74-fold higher (95% CI 1.70 to 4.24) in patients age 45 to 60 with prior cardiac disease or diabetes mellitus, but not higher in other age subgroups. Stroke was not increased above predicted. Risk scores for cardiac (c = 0.65, P = 0.003) and stroke (c = 0.71, P = 0.004) events were modest predictors. 10-yr event scores for cardiac (9.3 versus 13.5%, P < 0.001) and stroke (7.1 versus 10.0%, P = 0.002) were lower for tacrolimus compared with cyclosporine-treated patients. However observed cardiac events were higher in tacrolimus recipients (2.50, 95% CI 1.09 to 5.90) in an adjusted Cox model.

CONCLUSIONS

Although risk scores are only modest predictors, patients with the highest event rates are easily identified. Treating high-risk patients with cardioprotective medications should remain a priority.

Incidence of Cardiovascular Events in Renal Transplant Recipients and Clinical Relevance of Modifiable Variables

INTRODUCTION

The aims of this study were to quantify the incidence of cardiovascular events and identify the clinical relevance of modifiable variables.

MATERIALS AND METHODS

The 1729 patients who underwent renal transplantation from 1981 to 2004 were evaluated in an observational, prospective follow-up study with no exclusions. A cardiovascular event was defined as the presence of ischemic cardiac disease (chest pain-myocardial infarction), cardiac insufficiency, arrhythmia (auricular fibrillation), peripheral vascular disease, or cerebrovascular accident. A survival analysis was performed using the Kaplan-Meier method. A Cox regression analysis was applied. Having identified the predictive variables of cardiovascular events, the population attributable fraction (PAF) and the etiological fraction (EF) were estimated. A risk score was calculated using Cox regression coefficients.

RESULTS

The accumulated incidence of cardiovascular events was 22.2%, with an incidence rate of 468.6 x 10,000 follow-up years. From the Cox regression model, the variables with an independent effect close to statistical significance to predict cardiovascular events were as follows: recipient age (RR = 1.05), smoking at the time of the transplantation (RR = 2.1), left ventricle hypertrophy during follow-up (RR = 2.4), prior diabetes mellitus, and obesity (body mass index >or=30). At the time of transplantation, 41.7% were smokers. During follow-up, a clear difference was observed in the incidence rates of cardiovascular events between smokers and nonsmokers. Similar phenomena were observed for left ventricle hypertrophy and obesity. The resulting scores ranged between 0 and 5. The area under the ROC curve of the score for the prediction of cardiovascular events was 0.74.

CONCLUSION

The incidence of cardiovascular events was consistent with the literature. A series of modifiable variables of major clinical relevance exist to decrease the frequency of cardiovascular events following renal transplantation.

Perioperative management of immunosuppression

Current immunosuppressive regimens typically consist of two phases: induction phase (medications given at the time of the initial transplant) and maintenance therapy. Induction medications are given to decrease the occurrence of early acute rejection, avoid or minimise corticosteroids, and potentially induce long-term favourable immunoregulatory effects. As tolerance remains an elusive goal, life-long maintenance immunosuppression is required after all solid-organ transplantations. The various agents used in these two phases of immunosuppression are reviewed in this article. The similarities and differences between the agents within each class, with respect to efficacy and tolerability, are discussed.

Impaired Arterial Compliance and Aerobic Endurance in Kidney Transplant Recipients

BACKGROUND

Cardiovascular disease is the leading cause of morbidity and mortality in kidney transplant recipients (KTR). Two risk factors for cardiovascular disease that have not been examined in this population are arterial compliance and aerobic capacity. The primary objective was to determine small and large artery compliance and aerobic endurance in KTR. A secondary objective was to explore the relationship between aging and arterial compliance and aerobic endurance in KTR.

METHODS

Sixty-two clinically stable KTR were recruited from the University of Alberta Renal Transplant Clinic. Small and large artery compliance was assessed using computerized arterial pulse waveform analysis. Aerobic endurance was determined using the six-minute walk test. Age-matched normative data from healthy individuals was used for comparison.

RESULTS

Small arterial compliance was lower in KTR (5.5+/-3 ml/mm Hg x 100) compared to age-matched healthy individuals' predicted values (7.9+/-0.9 ml/mm Hg x 100, P<0.0001). No difference was found for large artery compliance between KTR (16.0+/-6.6 ml/mm Hg x 10) and age-matched healthy predicted values (15.2+/-1.3 ml/mm Hg x 10, P=0.5). Small and large artery compliance were 35% (P=0.026) and 36% (P=0.005) higher in younger (<51 years) versus older (>51 years) KTR, respectively. The six-minute walk distance was 28% lower in KTR (495+/-92 m) compared to healthy age-predicted values (692+/-56 m P<0.0001).

CONCLUSIONS

Compromised arterial compliance and poor aerobic endurance may partially explain the high incidence of cardiovascular disease in KTR. Interventions demonstrated to improve these parameters may afford substantial clinical benefit in this population.

Steroid-free immunosuppression regime reduces both long-term cardiovascular morbidity and patient mortality in renal transplant recipients

The aim of this retrospective study was to assess the impact of steroid therapy on cardiovascular disease (CVD) and patient mortality, in 486 on-CsA renal transplant recipients, with a follow-up of 9.5 +/- 4.3 yr. Two hundred and one patients had their steroids permanently withdrawn at sixth month after transplantation (G1); 285 patients did not (G2) as they were unable (acute rejection after suspension) or unsuitable (because of clinical criteria or immunosuppressive protocols). The CVD considered were coronary artery disease diagnosed by angiography and myocardial infarction. G1 and G2 patients were well-matched regarding CVD risk factors, except for age (G1: 44 +/- 14 yr; G2: 40 +/- 12 yr; p < 0.003), incidence of male (G1: 62%; G2: 72%, p < 0.02) incidence of acute rejection (G1: 39%; G2: 83%, p < 0.0001). Both CVD and deaths occurring during the first year of transplantation were excluded from the analysis. At 20 yr, the cumulative probability of developing a CVD, was 3.8% in G1; 23.8% in G2 (p < 0.0005). Patient survival rate was 95% in G1; 62% in G2 (p < 0.003). Mortality caused by CVD was higher in G2 (4.2% vs. 0.5%; p < 0.03). The Cox analysis identified in steroid therapy the main independent risk factors for both CVD (hazard ratio 9.56 p < 0.0001) and patient mortality (hazard ratio 5.99, p < 0.0001). At 10th and 15th year after transplantation, the mean-daily dose of steroids was 4.2 mg. In the long-term, steroid therapy, even in low-doses, increases significantly both the rate of CVD and patient mortality. This retrospective study suggests that steroid-free regime should always be recommended for the prevention of post-transplant CVD. This relevant statement should be followed by a long-term prospective study.

Simultaneous corticosteroid avoidance and calcineurin inhibitor minimization in renal transplantation

Steroids and calcineurin inhibitors (CNI) have been mainstays of immunosuppression but both have numerous side effects that are associated with substantial morbidity and mortality. This study was carried out to determine if steroids can be eliminated with early discontinuation of cyclosporine A (CsA) and later discontinuation of mycophenolate mofetil (MMF). Ninety-six patients with kidney transplants were entered into four subgroups of two pilot studies. All patients received Thymoglobulin induction, rapamycin (RAPA), and the immunonutrients arginine and an oil containing omega-3 fatty acids. Mycophenolate mofetil was started in standard doses and discontinued by 2 years. CsA was given in reduced doses for either 4, 6, or 12 months. Follow-up was 12-36 months. Thirteen first rejection episodes occurred during the first year (14%). Combining all patients, 86% were rejection-free at 1 year, 80% at 2 years and 79% at 3 years. No kidney has been lost to acute rejection. Ninety percent of the 84 patients at risk at the end of the study were steroid-free and 87% were off CNI. Fifty-seven percent of 54 patients with a functioning kidney at 3 years were receiving monotherapy with RAPA. We conclude that this therapeutic strategy is worthy of a prospective multi-center clinical trial.

Tacrolimus as secondary intervention vs. cyclosporine continuation in patients at risk for chronic renal allograft failure

BACKGROUND

Chronic renal allograft failure (CRAF) is the leading cause of graft loss post-renal transplantation. This study evaluated the efficacy and safety of tacrolimus as secondary intervention in cyclosporine-treated kidney transplantation patients with impaired allograft function as indicated by elevated serum creatinine (SCr) levels.

METHODS

Patients receiving cyclosporine-based immunosuppression who had an elevated SCr at least 3 months post-renal transplantation were enrolled. Treatment allocation was 2:1 to switch to tacrolimus or continue cyclosporine. This analysis was performed after 2 yr; patients will be followed for an additional 3 yr.

RESULTS

There were 186 enrolled and evaluable patients. On baseline biopsy, 90% of patients had chronic allograft nephropathy. Baseline median SCr was 2.5 mg/dL in both treatment groups. For patients with graft function at month 24, SCr had decreased to 2.3 mg/dL in the tacrolimus-treated patients and increased to 2.6 mg/dL in the cyclosporine-treated patients (p = 0.01). Acute rejection occurred in 4.8% of tacrolimus-treated patients and 5.0% of cyclosporine-treated patients during follow-up. Two-year allograft survival was comparable between groups (tacrolimus 69%, cyclosporine 67%; p = 0.70). Tacrolimus-treated patients had significantly lower cholesterol and low-density lipoprotein levels and also had fewer new-onset infections. Cardiac conditions developed in significantly fewer tacrolimus-treated patients (5.6%) than cyclosporine-treated patients (24.3%; p = 0.004). Glucose levels and the incidences of new-onset diabetes and new-onset hyperglycemia did not differ between treatment groups.

CONCLUSIONS

Conversion from cyclosporine to tacrolimus results in improved renal function and lipid profiles, and significantly fewer cardiovascular events with no differences in the incidence of acute rejection or new-onset hyperglycemia.

Anaemia after renal transplantation

Anaemia is a frequent complication among long-term renal transplant recipients. A prevalence of approximately 40% has been reported in several studies. If renal function declines to stage 5 kidney disease, the prevalence of anaemia in kidney transplants is even higher. A positive correlation between haemoglobin concentration and creatinine clearance has been reported, which is a function of endogenous erythropoietin production by the functioning graft. Inflammation related to a retained kidney graft may cause hypo-responsiveness to erythropoietic agents once kidney transplant recipients return to dialysis. Furthermore, the use of azathioprine, mycophenolate mofetil and sirolimus may be associated with post-transplant anaemia. Along with erythropoietin deficiency, depletion of iron stores is one of the major reasons for anaemia in the kidney transplant population. The proportion of hypochromic red blood cells appears to be a useful parameter to measure iron supply and utilization as well as to estimate mortality risks in kidney transplant recipients. While anaemia is an important cardiovascular risk-factor after transplantation, our data suggest that anaemia is not associated with mortality and graft loss. Nevertheless, inadequate attention is paid so far to the management of anaemia after renal transplantation. A promising future aspect for risk reduction of cardiovascular disease includes the effect of erythropoietic agents on endothelial progenitor cells.

Coronary event rates in liver transplant recipients reflect the increased prevalence of cardiovascular risk-factors

Increased prevalence of cardiovascular risk-factors in liver transplant recipients compared with pretransplant and standard population data has been acknowledged. The impact of risk-profiles on cardiovascular event rates or death, however, has not yet been established. Here we evaluate the development of risk-factors during a prospective follow-up of 10 years in 302 patients and compare numbers of coronary events with data from the German Prospective Cardiovascular Münster (PROCAM)-Score population. Prevalence of overweight (17% vs. 27%), hypertension (70% vs. 80%), and diabetes (21% vs. 25%) increased from early to late after transplantation, while elevated serum cholesterol (64% vs. 37%) and triglycerides (40% vs. 21%) became less frequent. Cardiovascular risk-profiles favoring tacrolimus over ciclosporin A based immunosuppression early after transplantation converged over time. Increased risk-scores in liver transplant recipients matched with score standardized event rates in the PROCAM population (ratio: 1.11, 95% CI: 0.53-2.03), nine events were predicted for the transplant population and oppose 10 events observed. Thus, indicating a reflection of increased cardiovascular risk-profiles in corresponding numbers of cardiovascular events.

Graft Function, Cardiovascular Risk Factors, and Sex Hormones in Renal Transplant Recipients on an Immunosuppressive Regimen of Everolimus, Reduced Dose of Cyclosporine, and Basiliximab

A prospective, randomized trial evaluated the combination of everolimus of 1.5 or 3 mg/d with steroids, basiliximab, and low-dose cyclosporine (CsA) adjusted by C2 monitoring in 256 renal transplant recipients. CsA C2 target levels, initially set at 600 ng/mL, were tapered over time posttransplant. The median serum creatinine concentrations were 130 mumol/L in both sirolimus groups (1.5 and 3 mg/d) at 6 months. Biopsy-proven acute rejection (BPAR) occurred in 13.7% and 15.1% of patients in the 1.5 and 3 mg/d groups, respectively. The incidence of BPAR was significantly higher among patients with everolimus trough levels < 3 ng/mL. Posttransplant diabetes mellitus occurred rarely, and blood pressure control appeared favorable; however, serum cholesterol levels were increased by approximately 50%, and serum triglycerides by approximately 100%. Serum testosterone concentrations increased after renal transplantation in both everolimus groups. Concentration-controlled everolimus therapy combined with low-dose CsA provides effective protection against rejection with good renal function and safety profiles.

Rational development of LEA29Y (belatacept), a high-affinity variant of CTLA4-Ig with potent immunosuppressive properties

Current success in organ transplantation is dependent upon the use of calcineurin-inhibitor-based immunosuppressive regimens. Unfortunately, current immunotherapy targets molecules with ubiquitous expression resulting in devastating non-immune side effects. T-cell costimulation has been identified as a new potential immunosuppressive target. The best characterized pathway includes CD28, its homologue CTLA4 and their ligands CD80 and CD86. While an immunoglobulin fusion protein construct of CTLA4 suppressed rejection in rodents, it lacked efficacy in primate transplant models. In an attempt to increase the biologic potency of the parent molecule a novel, modified version of CTLA4-Ig, LEA29Y (belatacept), was constructed. Two amino acid substitutions (L104E and A29Y) gave rise to slower dissociation rates for both CD86 and CD80. The increased avidity resulted in a 10-fold increase in potency in vitro and significant prolongation of renal allograft survival in a pre-clinical primate model. The use of immunoselective biologics may provide effective maintenance immunosuppression while avoiding the collateral toxicities associated with conventional immunsuppressants.

Overview of tacrolimus-based immunosuppression after heart or lung transplantation

Transplantation has evolved into an accepted treatment for end-stage heart or lung disease. Acute rejection, complications related to immunosuppressive protocols, and the development of chronic rejection continue to challenge the long-term success of heart and lung transplantations. Wide acceptance of tacrolimus as an important immunosuppressant in renal and hepatic transplantations has led subsequently to its investigation as primary immunosuppression in heart and lung transplant recipients, either combined with azathioprine or with the newer agents mycophenolate mofetil or rapamycin. Studies have shown that tacrolimus is an effective therapeutic alternative to cyclosporine for primary immunosuppression in heart or lung transplantation and demonstrates equivalent if not improved prophylaxis of acute rejection, and more recently demonstrates a potential influence on chronic rejection, particularly in lung transplant recipients. Of importance, the enhanced immunosuppressive activity of tacrolimus is achieved without increased risk of infection or malignancy. Differences in tolerability profiles and side effects between tacrolimus and cyclosporine may be used in selecting the optimal immunotherapy after thoracic transplantation. In particular, the lesser propensity of tacrolimus to cause hypertension and hyperlipidemia potentially offers decreased cardiovascular risk for heart and lung transplant recipients.

Pancreas and islet cell transplantation

Transplantation of the pancreas or islet cells constitutes surgical treatment for patients with type 1 diabetes mellitus. Pancreas transplantation is now an established procedure for the surgical treatment of diabetes mellitus. Islet cell transplantation has the potential to be the procedure of choice once it becomes more routine because of the minimal surgery involved. Included in this chapter are the pathophysiology of diabetes, rationale for transplantation, and the surgical procedure itself.

Pre-emptive treatment with oral valganciclovir in management of CMV infection after cardiac transplantation

BACKGROUND

Cytomegalovirus (CMV) has long been recognized as the most common opportunistic pathogen in transplant recipients. The use of post-detection antiviral treatment of CMV as a strategy to prevent disease in cardiac recipients is becoming the standard policy. Valganciclovir is an oral pro-drug of ganciclovir, with a 10-fold greater bioavailability than oral gancyclovir.

PATIENTS AND METHODS

We reported our first experience with 8 patients (3 female, 45.0 +/- 10.5 years old, non-CMV mismatched) who underwent cardiac transplantation and had positive results of CMV polymerase chain reaction (PCR) within first 6 weeks after transplantation without concomitant CMV disease. These patients received valganciclovir in dosage 450 to 900 mg daily depending on renal function for 3 weeks. Standard immunosuppressive regimen consisted of cyclosporin A, MMF and corticosteroids, and was not changed after detection of CMV infection. In one patient we used sirolimus with respectively reduced dosage of cyclosporin A. Weekly measurements of CMV-PCR were performed to observe results of therapy.

RESULTS

After 1 week of valganciclovir therapy CMV-PCR plasma concentration in all patients decreased significantly (2,105 copies/ml vs 400 copies/ml; p < 0.0001). No relapse of CMV infection has been detected after completing of valganciclovir therapy with follow up duration of 9.0 +/- 0.92 months. The drug was generally well tolerated, and we did not observe any severe drug related adverse events.

CONCLUSION

Oral valganciclovir as pre-emptive antiviral therapy administrated after detection of CMV infection seems to be an effective and safe treatment in cardiac transplant recipients.

An update on clinical outcomes in heart and lung transplantation

Much progress has been made in heart and lung transplantation over recent decades. The immune mechanisms that result in allograft rejection are now better understood, and the development of immunosuppressant therapies has decreased recipient mortality among transplant recipients. During the 1980s, immunosuppressant therapy primarily involved the use of corticosteroids and cyclosporine. However, while survival rates increased among transplant recipients, many patients experienced primary graft failures, acute and chronic rejection, as well as death. Until the introduction of tacrolimus in the early 1990s, all patients received the same immunosuppressant regimen, regardless of its effectiveness. Tacrolimus therapy has contributed much to the success rates of both heart and lung transplantation, and by 2001, it had become the preeminent immunosuppressant agent used in lung transplantation.

The benefits of renin-angiotensin blockade in renal transplant recipients with biopsy-proven allograft nephropathy

BACKGROUND

Allograft nephropathy, regardless of aetiology, leads to progressive renal injury and eventual graft loss. In native kidney disease, treatment of hypertension, in particular with angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB), has proven beneficial in retarding renal function decline. In the present study, we reviewed the clinical course of a renal transplant recipient cohort that was prescribed either an ACEi or ARB for biopsy-proven allograft nephropathy.

METHODS

Patients were followed from the time of post-biopsy initiation of ACEi/ARB and were stratified based on biopsy findings. Outcomes of interest included safety, allograft survival, renal function and change in slope of renal function pre- and post-ACEi/ARB.

RESULTS

The 5 year allograft survival after biopsy diagnosis of allograft nephropathy was 83%. Serum creatinine was 191+/-97 (86-377) micromol/l at the time of biopsy and 228+/-102 (102-575) micromol/l at last follow-up. The slopes of reciprocal creatinine vs time were used to calculate the decline in renal function and were compared pre- and post-ACEi/ARB. The mean slope+/-SD was -0.06+/-0.21 l/micromol x 10(-3) per month in the 12 months prior to therapy and -0.03+/-0.09 l/micromol x 10(-3) per month following therapy. The absolute difference in slopes was 0.03 (P =<0.0001).

CONCLUSIONS

Treatment with ACEi/ARB may be beneficial in the management of allograft nephropathy.