Patient survival after renal transplantation: IV. Impact of post-transplant diabetes

Pilot study: association of traditional and genetic risk factors and new-onset diabetes mellitus following kidney transplantation

INTRODUCTION

New-onset diabetes mellitus, which occurs after kidney transplant and type 2 diabetes mellitus (T2DM), shares common risk factors and antecedents in impaired insulin secretion and action. Several genetic polymorphisms have been shown to be associated with T2DM. We hypothesized that transplant recipients who carry risk alleles for T2DM are "tipped over" to develop diabetes mellitus in the posttransplant milieu.

METHODS

We investigated the association of genetic and traditional risk factors present before transplantation and the development of new-onset diabetes mellitus after kidney transplantation (NODAT). Markers in 8 known T2DM-linked genes were genotyped using either the iPLEX assay or allelic discrimination (AD)-PCR in the study cohort testing for association with NODAT. We used univariate and multivariate logistic regression models for the association of pretransplant nongenetic and genetic variables with the development of NODAT.

RESULTS

The study cohort included 91 kidney transplant recipients with at least 1 year posttransplant follow-up, including 22 who developed NODAT. We observed that increased age, family history of T2DM, pretransplant obesity, and triglyceridemia were associated with NODAT development. In addition, we observed positive trends, although statistically not significant, for association between T2DM-associated genes and NODAT.

CONCLUSIONS

These findings demonstrated an increased NODAT risk among patient with a positive family history for T2DM, which, in conjunction with the observed positive predictive trends of known T2DM-associated genetic polymorphisms with NODAT, was suggestive of a genetic predisposition to NODAT.

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.

Post-transplant glucose status in 61 pediatric renal transplant recipients: preliminary results of five Turkish pediatric nephrology centers

To assess the incidence, risk factors and outcomes of PTDM, a total of 61 non-diabetic children (24 girls, 37 boys, age: 14.5 +/- 2.1 yr) were examined after their first kidney transplantation (37.3 +/- 21.6 months) with an OGTT. At baseline, 16 (26.2%) patients had IGT, 45 (73.8%) had NGT, and no patient had PTDM. No significant difference was shown between TAC- and CSA-treated patients in terms of IGT. Higher BMI z-scores (p = 0.011), LDL-cholesterol (p < 0.05) and triglyceride levels (p < 0.01), HOMA-IR (p = 0.013) and lower HOMA-%beta (p = 0.011) were significantly associated with IGT. Fifty-four patients were re-evaluated after six months; eight patients with baseline IGT (50%) improved to NGT, three (19%) developed PTDM requiring insulin therapy, five (31%) remained with IGT, and four patients progressed from NGT to either IGT (two) or PTDM (two). These 12 progressive patients had significantly higher total cholesterol (p < 0.05), triglycerides (p < 0.05), HOMA-IR (p < 0.01) and lower HOMA-%beta (p < 0.0) than non-progressive patients at baseline. We can conclude that post-transplantation glucose abnormalities are common in Turkish pediatric kidney recipients, and higher BMI z-scores and triglyceride concentrations are the main risk factors. Considering that the progressive patients are significantly more insulin resistant at baseline, we suggest that the utility of both HOMA-IR and HOMA-%beta in predicting future risk of PTDM and/or IGT should be evaluated in children.

Prevalence evolution and impact of cardiovascular risk factors on allograft and renal transplant patient survival

OBJECTIVE

The prevalence of traditional cardiovascular risk factors in renal transplantation is high. Studying the evolution of cardiovascular risk factors over time may help us to design better strategies to control them. The relative impact of traditional cardiovascular risk factors on allograft survival and mortality in transplant recipients is not clear. This study was performed to determine the incidence and risk factors for allograft survival and mortality among renal transplant patients.

PATIENTS AND METHODS

We enrolled 250 patients who had undergone transplantation between 1980 and 2004. They were followed for various periods, and we analyzed the impact of traditional and nontraditional risk factors on renal allograft survival.

RESULTS

The prevalence of hypertension was >80% during all the follow-up periods. Blood pressure diminished, antihypertensive drug prescription increased, and 15% of patients had adequate blood pressure control during follow-up. The prevalence of pretransplant diabetes mellitus was 6.8%; the incidence of posttransplant diabetes mellitus (PTDM) was 14.2%. The prevalence of PTDM increased over the course of patient evolution. The prevalence of dyslipidemia was in all cases >70%; total cholesterol and low-density lipoprotein (LDL)-cholesterol decreased; prescription of statins increased; and the percentage of patients with good lipid control also increased. The 25% prevalence of active smoking at the time of transplantation decreased to 13.6% at 10 years posttransplantation. The mean patient follow-up was 8 +/- 4.6 years. Sixty-five patients (26%) lost their grafts and 40 (16%) died during follow-up. Donor age, exercise, diastolic blood pressure, renal function, and albumin levels were independent risk factors for graft loss. Charlson comorbidity index at transplantation, recipient and donor ages, exercise, diastolic blood pressure, and LDL-cholesterol posttransplantation were independent risk factors for mortality among renal transplant recipients.

CONCLUSION

Blood pressure and lipid control improved during follow-up, however, insufficiently among renal transplant patients. The prevalence of diabetes gradually increased, and the incidence of smoking cessation was low. Diastolic blood pressure, exercise, and albuminemia were the most significant modifiable cardiovascular risk factors for renal allograft survival. Diastolic blood pressure, LDL-cholesterol level, and exercise were the most relevant modifiable cardiovascular risk factors for the survival of renal transplant patients.

Posttransplant diabetes mellitus: incidence and risk factors

OBJECTIVE

Posttransplant diabetes mellitus (PTDM) is a common and serious complication of renal transplantation. Estimates of the incidence of PTDM after renal transplantation vary between 2% and 54%. The aim of the present study was to evaluate the incidence and risk factors for PTDM among our renal transplant patients.

PATIENTS AND METHODS

In this study we evaluated 121 nondiabetic patients with end-stage renal disease (ESRD) who underwent kidney transplantation for the first time at our centers since 2005. All patients received the same protocol of immunosuppressive therapy. PTDM was defined according to the clinical practice recommendations of the American Diabetes Association.

RESULTS

At 12 months following renal transplantation, 9.9% of patients developed PTDM. Patients with PTDM were significantly older (P = .013) and had higher body mass index (P = .001). There were significant differences (P <or= .05) between PTDM and non-PTDM patients with respect to systolic blood pressure, serum triglycerides (TG), peritoneal dialysis as renal replacement therapy before transplantation, and duration of pretransplant dialysis therapy. Upon multivariate analysis, serum TG, systolic blood pressure, and body mass index were associated with PTDM (P <or= .05).

CONCLUSIONS

The incidence at 12 months of PTDM among our renal transplant recipients was 9.9%. The most important factors associated with PTDM were serum TG, systolic blood pressure, and body mass index.

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.

Advanced glycation end products enhance monocyte activation during human mixed lymphocyte reaction

Posttransplant diabetes mellitus (PTDM) is a frequent complication among transplant recipients. Ligation of advanced glycation end products (AGEs) with their receptor (RAGE) on monocytes/macrophages plays roles in the diabetes complications. The enhancement of adhesion molecule expression on monocytes/macrophages activates T-cells, leading to reduced allograft survival. We investigated the effect of four distinct AGE subtypes (AGE-2/AGE-3/AGE-4/AGE-5) on the expressions of intracellular adhesion molecule (ICAM)-1, B7.1, B7.2 and CD40 on monocytes, the production of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha and the proliferation of T-cells during human mixed lymphocyte reaction (MLR). AGE-2 and AGE-3 selectively induced the adhesion molecule expression, cytokine production and T-cell proliferation. The AGE-induced up-regulation of adhesion molecule expression was involved in the cytokine production and T-cell proliferation. AGE-2 and AGE-3 up-regulated the expression of RAGE on monocytes; therefore, the AGEs may activate monocytes, leading to the up-regulation of adhesion molecule expression, cytokine production and T-cell proliferation.

Impact of glucose metabolism abnormalities on histopathological changes in kidney transplant protocol biopsies

The impact of post-transplant diabetes (PTDM) on kidney transplant histopathology has been poorly described. We examined the association of glucose metabolism abnormalities on the progression of histopathological changes in serial protocol biopsies. Helsinki University Hospital kidney transplant recipients during 2004-2006 were followed up. Patients with pre-existing diabetes or 2-h oral glucose tolerance test (OGTT) performed at 3 months, and protocol biopsies taken at 0 and 12 months were analyzed (n = 76). Diabetes was defined according to WHO/ADA. Histology was analyzed with chronic allograft damage index (CADI). Altogether 32 patients had pre-existing diabetes. In OGTT at 3 months, four showed PTDM, eight impaired glucose tolerance (IGT), two impaired fasting glucose, and 30 normal glucose tolerance. Patients with impaired glucose metabolism were older (P = 0.005), received grafts from older donors (P = 0.04), and had reduced renal function at 12 months (P = 0.003). In patients with IGT or PTDM, 2-h postload glucose values in OGTT correlated with CADI at 12 months (R = 0.84, P = 0.001) and with the change in CADI score between 0 and 12 months (R = 0.67, P = 0.025). Graft survival was reduced in patients with pre-existing diabetes (P = 0.01). Glucose abnormalities were associated with the progression of histopathological changes, especially in patients with already compromised kidneys, supporting the harmful role of PTDM to the kidney allograft.

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 diabetes mellitus

In recent decades, Diabetes Mellitus has become a severe and growing global public healthcare problem due to the increase of its prevalence, morbidity and mortality. Post-transplant diabetes mellitus (PTDM) is a complication which takes place after a solid organ transplant, and its incidence is widely variable, ranging from 2 to 53%. Some factors increase the risk of PTDM, such as age, ethnicity, cadaver-donor kidney presence of the hepatitis C virus and cytomegalovirus, overweight and obesity and the Immunosuppression scheme established in the immediate post-transplant period. High doses of tacrolimus and corticosteroid represent the highest risk for developing PTDM.Considering that the development of PTDM is associated with a higher risk of complications, such as infections and cardiovascular disease - thus representing a higher life threatening risk and a higher cost for the Health System - the relevance of identifying the risk factors and of the early diagnosis combined with appropriate therapy will be high for the follow up, and eventually resulting in the success of the procedure as far as patient survival and transplantation durability.

Increasing incidence of new-onset diabetes after transplant among pediatric renal transplant patients

BACKGROUND

Risk of new-onset diabetes after transplant (NODAT) is well characterized for adults but much less understood in pediatric transplant. This study examines the incidence and risk factors of NODAT in pediatric renal transplant patients.

METHODS

The incidence of NODAT over the first 3 years after transplant was examined with the United States Renal Data System data for primary renal transplant recipients (ages 0-21 years, transplanted between 1995 and 2004) with Medicare primary. Patients had no evidence of diabetes before transplant. We estimated the cumulative incidence rate and used Cox proportional hazards regression to identify the risk factors for NODAT. Propensity scores were calculated for immunosuppression choice to adjust for potential confounding factors.

RESULTS

Two thousand one hundred sixty-eight recipients with valid immunosuppression records and without pretransplant evidence of diabetes were included. Unadjusted, cumulative NODAT incidence at 3 years posttransplant was 7.1%. Significant factors for increased risk of NODAT included cytomegalovirus D+/R- serostatus (adjusted hazard ratio [aHR]=1.60), age 13 to 18 years (aHR=2.18), age 19 to 21 years (aHR=2.60), body mass index more than or equal to 30 kg/m (aHR=2.17), and use of tacrolimus (aHR=1.51). We failed to find any significant relationships between NODAT and graft failure or death.

CONCLUSIONS

Although the incidence of NODAT among patients aged 0 to 21 years is lower than that for adult patients, it is higher than suggested by earlier research and may represent an increase over time. The lack of association between NODAT and graft or failure death has important implications for posttransplant care. A clearer understanding of risk factors can help guide posttransplant monitoring and clinical decision making.

Influence of sirolimus on cyclosporine-induced pancreas islet dysfunction in rats

This study was performed to investigate the effect of sirolimus (SRL) on cyclosporine (CsA)-induced pancreatic islet dysfunction in rats. Three separate studies were performed. First, diabetogenic effect of SRL was evaluated with three different doses (0.15, 0.3 and 0.6 mg/kg). Second, rats were treated with SRL (0.3 mg/kg) with or without CsA (15 mg/kg) for 4 weeks. Third, rats were treated with CsA for 4 weeks, and then switched to SRL for 4 weeks. The effect of SRL on CsA-induced pancreatic islet dysfunction was evaluated by an intraperitoneal glucose tolerance test, plasma insulin concentration, HbA1c level, HOMA-R index, immunohistochemistry of insulin and pancreatic beta islet cell mass. The SRL treatment increased blood glucose concentration in a dose-dependent manner. The combined treatment with SRL and CsA increased blood glucose concentration, Hemoglobin A1c (HbA1c) level, HOMA-R [fasting insulin (mU/mL) x fasting glucose (mmol/L)]/22.5] index and decreased plasma insulin concentration, immunoreactivity of insulin and pancreatic beta islet cell mass compared with rats treated with CsA. CsA withdrawal for 4 weeks improved pancreatic beta-cell function and structure. However, conversion from CsA to SRL further increased blood glucose levels compared with the rats converted from vehicle to SRL. The results of our study demonstrate that SRL is diabetogenic and aggravates CsA-induced pancreatic islet dysfunction.

Mammalian target of rapamycin and diabetes: what does the current evidence tell us?

New-onset diabetes mellitus after transplantation (NODAT) is a serious complication in organ transplantation; not only does it enhance the risk of graft dysfunction, it also increases cardiovascular morbidity and mortality. The mammalian target of rapamycin (mTOR) is regulated independently by insulin, amino acids, and energy sufficiency. It integrates signal from growth factors, hormones, nutrients, and cellular energy levels to regulate protein translation and cell growth, proliferation, and survival. In addition, mTOR generates an inhibitory feedback loop on insulin receptor substrate (IRS) proteins. Therefore, it was suggested that mTOR might link nutrient excess with both obesity and insulin resistance. In this review, we summarize the role of mTOR and its inhibitor sirolimus (SRL) on chronic hyperglycemia and insulin resistance in beta cells, adipose tissue, liver, and muscle. We further hypothesize, based on data from the literature and generated in our laboratory, that SRL could counteract the development of NODAT in stable glucose homeostasis due to its positive effects on insulin-stimulated glucose uptake, whereas in conditions that require an adaptive beta cell proliferation (such as pregnancy and weight increase), the administration of SRL might have effects that would promote the development of NODAT. Therefore, it seems crucial for patient outcome to consider these potentially contrasting effects of SRL.

Review article: New-onset diabetes after transplantation

SUMMARY

This article reviews the clinical aspects and epidemiological links between diabetes mellitus and renal transplantation, and emphasizes areas that warrant further clarification. In particular, we summarize the data for various immunosuppression medications on the risk of new-onset diabetes after transplantation (NODAT). An increased mechanistic understanding of new-onset diabetes might provide new insights into the pathophysiology of this complication after solid organ transplantation. Claims that selecting immunosuppression regimen to minimize the risk of NODAT, nevertheless, are currently not supported by the scientific published work. Intuitively, strategies that aim to change the underlying biology of the disease process of NODAT are desirable; among them, lifestyle modification is currently the most promising in terms of real benefit with the least risk.

New-onset diabetes mellitus after solid organ transplantation

New-onset diabetes mellitus is a common complication of solid organ transplantation and is likely to become even more common with the current epidemic of obesity in some countries. It has become clear that both new-onset diabetes and prediabetic states (impaired fasting glucose and impaired glucose tolerance) negatively influence graft and patient survival after transplantation. This observation forms the basis for recommending meticulous screening for glucose intolerance before and after transplantation. Although a number of clinical factors including age, weight, ethnicity, family history, and infection with hepatitis C are closely associated with the new-onset diabetes mellitus, immunosuppression with corticosteroids, calcineurin inhibitors and possibly sirolimus plays a dominant role in its pathogenesis. Management of new-onset diabetes after transplantation generally conforms to the guidelines for treatment of type 2 diabetes mellitus in the general population. However, further studies are needed to determine the optimal immunosuppressive regimens for patients with this disorder.

Management of new-onset diabetes mellitus after transplantation

Solid organ transplantation is now the standard of care for end-stage organ failure, and primary care physicians are frequently involved in the follow-up care of transplant recipients. New-onset diabetes mellitus after solid organ transplantation (NODAT) has emerged as an increasingly important determinant of outcomes and survival in transplant recipients. Transplant recipients are at high risk for developing prediabetes and overt diabetes mellitus due to a number of factors, including immunosuppressive therapies. This article presents an algorithmic approach with supporting evidence to provide a rational framework for selecting the appropriate therapy among numerous treatment options. Patient education and self-management are crucial for ensuring a successful outcome post transplantation.

Comparative risk of impaired glucose metabolism associated with cyclosporine versus tacrolimus in the late posttransplant period

New onset diabetes after transplantation (NODAT) and impaired fasting glucose (IFG) are common in kidney transplant recipients (KTRs). Calcinuerin inhibitor (CNI) therapy is a causal risk factor. NODAT is associated with increased mortality and diminished graft survival. We studied the incidence of NODAT and IFG in KTRs before and after a medically indicated switch of CNI therapy from cyclosporine (CsA) to tacrolimus (Tac). The study population consisted of 704 nondiabetic KTRs. Of them, 171 underwent conversion from CsA to Tac (group I) and 533 remained on the CsA since transplantation (Group II). Time-dependent Cox regression and generalized estimating equations were used to account for sequential CNI exposure. NODAT and IFG occurred in 15.2% and 22.1% of group I subjects and 15.6% and 25.8% of group II subjects, respectively (p = 0.90 for NODAT and p = 0.38 for IFG). Accounting for equal follow-up time since conversion from CsA to Tac, the adjusted 5-year NODAT-free survival was 87.4% and 91.4% in group I and group II, respectively (p = 0.90). In conclusion, conversion to Tac, compared to continuous exposure to CsA, carries quantitatively similar risk of impaired glucose metabolism in KTRs in the late posttransplant period.

Insulin therapy in renal disease

Diabetes mellitus (DM) is the main cause of end-stage renal disease (ESRD). Conversely, chronic renal failure (CRF) is also associated with diverse alterations in carbohydrate and insulin metabolism. CRF-induced metabolic disorders should be borne in mind when treating diabetic patients, to ensure the introduction of adequate therapy adjustments that are in line with the onset of renal function decline. Moreover, several specific therapies employed in CRF may also influence pharmacological therapy of DM in uraemic patients. Adequate glycaemic control has also been associated with a reduction in the onset and progression of diabetic nephropathy as well as in the morbidity and mortality in uraemic diabetic patients during dialysis. Intensive insulin therapy can notably improve glycemic control and it should be considered part of the management of insulin-treated CRF diabetic patients. Insulin analogues have been recently evaluated in CRF diabetic patients, with encouraging results. In this study, we review the more relevant aspects related to insulin therapy in diabetic patients with different degrees of renal failure and in patients with ESRD, both in conservative therapy and dialysis.

Transplant-associated hyperglycemia

As patient survival after solid organ transplantation continues to improve, comorbidites associated with chronic hyperglycemia will assume increasing importance in limiting outcomes and quality of life. New-onset diabetes mellitus commonly occurs in the posttransplant setting and is associated with multiple complications including graft loss, cardiovascular disease, infection, and death. Furthermore, recent studies have begun to highlight the very high posttransplant prevalence and the significant cardiovascular implications of the prediabetic states of impaired fasting glucose and impaired glucose tolerance, indicating that the overall burden of transplantation-associated hyperglycemia is far greater than previously appreciated. Shared and distinct pathogenic factors and clinical repercussions exist among the organ-specific transplant scenarios. Diabetogenic immunosuppressive agents are common to all organ transplant settings, whereas glucose regulation is also strained by the restoration of failed hepatic and renal function. The atherogenic properties of hyperglycemia are particularly significant in the kidney transplant population, which has a marked predisposition to cardiovascular disease, whereas accelerated cardiac allograft vasculopathy and liver fibrosis have been associated with hyperglycemia in the heart and liver transplant settings, respectively. Aggressive screening will effectively detect transplant-associated hyperglycemia, whereas risk factor modification, lifestyle intervention and, where appropriate, drug therapy, may decrease its impact. Topics of future investigation should include the use of emerging diabetes therapies and avenues for the prevention and reversal of transplant-associated hyperglycemia.

The impact of new-onset diabetes on arterial stiffness after renal transplantation

New-onset diabetes after renal transplantation (NODAT) is known to be a potent risk factor for cardiovascular events. We therefore investigated the incidence and risk factors for NODAT, and evaluated surrogate endpoints of atherosclerosis in Japanese patients with stable renal function after renal transplantation. Seventy-nine patients were enrolled in the study, and a 75 g oral glucose tolerance test (OGTT) was performed in subjects excluding patients with known NODAT. We evaluated the risk factors for NODAT and the degree of atherosclerosis, determined by brachial-ankle pulse wave velocity (baPWV), ankle-brachial blood pressure index (ABPI) and intima-media thickness (IMT) of the carotid artery. Eleven patients diagnosed as NODAT had significantly higher fasting plasma glucose before transplantation, blood pressure, and incidence of hepatitis C virus (HCV) infection than patients without NODAT. Multivariate regression analysis revealed that the independent determinant of NODAT was fasting plasma glucose pre-transplantation, HCV infection and systolic blood pressure. The baPWV in patients with NODAT was significantly higher compared to that in patients without NODAT. In addition, the independent determinant of baPWV evaluated by multivariate regression analysis was an increase in systolic blood pressure and age, and a decrease of adiponectin levels. In conclusion, we found that high fasting plasma glucose prior to transplantation, HCV infection and high blood pressure are risk factors for NODAT in Japanese patients after renal transplantation. Since NODAT patients have advanced arterial stiffness probably due to high blood pressure, strict control of blood pressure will be important for preventing the development of cardiovascular disease in NODAT.

Dyslipidemia can be controlled in diabetic as well as nondiabetic recipients after kidney transplant

BACKGROUND

Patients with diabetes have been reported to have greater dyslipidemia after kidney transplant (KTX). Because postKTX management of diabetes has changed markedly since those reports, we hypothesized that lipids can be controlled as well in diabetic as in nondiabetic recipients.

METHODS

We compared lipid levels up to 2 years after KTX (n=192) between diabetic and nondiabetic recipients. The cohort was subdivided into nondiabetic (nonDM-K; n=123), type 2 (DM2-K; n=33), or type 1 diabetes after KTX (DM1-K; n=14), or type 1 after kidney-pancreas transplant (DM1-KP; n=22).

RESULTS

Mean age and body mass index of DM2-K were greater than the others (P<0.01), and diabetes groups had a higher pretransplant A1C than nonDM-K (P<0.001). After KTX, lipid levels were not higher in diabetic than in nondiabetic recipients, and did not increase in any group. Total and low-density lipoprotein cholesterol levels decreased in DM1-K (P<0.001), high-density lipoprotein levels decreased in DM1-KP (P=0.02), and triglyceride levels were unchanged after KTX for all groups. A1C improved in DM1-K and DM1-KP (P<0.0001). There was less improvement in lipid levels with tacrolimus-sirolimus immunosuppression than with other steroid-containing regimens (P<0.05).

CONCLUSIONS

Multiple mechanisms may contribute to better lipid levels in both groups as well as the lack of difference between diabetic and nondiabetic recipients compared with what has been reported previously: greater use of and more effective lipid-lowering agents, no significant weight gain, no difference in renal function between groups, and better control of glucose in the diabetic group. Thus, overall, lipids can be controlled as well in diabetic as in nondiabetic KTX recipients.

Influence of lifestyle modification in renal transplant recipients with postprandial hyperglycemia

INTRODUCTION

Lifestyle modification is recommended as first-line therapy to manage new-onset diabetes after transplantation (NODAT) and impaired glucose tolerance (IGT). No data currently demonstrate the efficacy of this approach specifically for transplant recipients. This study aimed to assess the benefit of intensive lifestyle modification in this high-risk group and to contrast this with the natural evolution of glucose metabolism after transplantation.

METHODS

Baseline oral glucose tolerance test (OGTT) stratified 115 patients into two groups. Group 1 had glucose intolerance, IGT (n=28) and NODAT (n=8), and received intensive lifestyle modification (dietician referral, exercise program, weight loss advice). Group 2 had normal glucose tolerance (n=79) and received lifestyle modification leaflets. Both groups had follow-up OGTT after 6 months to assess change in glycemic status.

RESULTS

Excluding all patients who received steroid weaning or withdrawal as part of their management, 111 patients were included in the analysis. Lifestyle modification in group 1 resulted in 15% improvement in 2-hr postprandial glucose versus 12% deterioration in group 2. In group 1, 44% (n=11) of IGT patients developed normal glucose tolerance, whereas only 4% (n=1) developed NODAT. Fifty-eight percent (n=4) of NODAT patients showed improvement (29% to IGT and 29% to normal). Glucose metabolism deteriorated in group 2 with 14% (n=10) developing IGT and 3% (n=2) developing NODAT.

CONCLUSIONS

Glucose metabolism can deteriorate in transplant recipients despite passive lifestyle modification advice. This study shows active lifestyle modification benefits high-risk transplant recipients with glucose intolerance and should be aggressively pursued.

Unmasking glucose metabolism alterations in stable renal transplant recipients: a multicenter study

BACKGROUND AND OBJECTIVES

Emerging information indicates that glucose metabolism alterations are common after renal transplantation and are associated with carotid atheromatosis. The aims of this study were to investigate the prevalence of different glucose metabolism alterations in stable recipients as well as the factors related to the condition.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A multicenter, cross-sectional study was conducted of 374 renal transplant recipients without pre- or posttransplantation diabetes. A standard 75-g oral glucose tolerance test was performed.

RESULTS

Glucose metabolism alterations were present in 119 (31.8%) recipients: 92 (24.6%) with an abnormal oral glucose tolerance test and 27 (7.2%) with isolated impaired fasting glucose. The most common disorder was impaired glucose tolerance (17.9%), and an abnormal oral glucose tolerance test was observed for 21.5% of recipients with a normal fasting glucose. By multivariate analysis, age, prednisone dosage, triglyceride/high-density lipoprotein cholesterol ratio, and beta blocker use were shown to be factors related to glucose metabolism alterations. Remarkably, triglyceride levels, triglyceride/high-density lipoprotein cholesterol ratio, and the proportion of recipients with impaired fasting glucose were already higher throughout the first posttransplantation year in recipients with a current glucose metabolism alteration as compared with those without the condition.

CONCLUSIONS

Glucose metabolism alterations are common in stable renal transplant recipients, and an oral glucose tolerance test is required for its detection. They are associated with a worse metabolic profile, which is already present during the first posttransplantation year. These findings may help planning strategies for early detection and intervention.

Unmasking glucose metabolism alterations in stable renal transplant recipients: a multicenter study

BACKGROUND AND OBJECTIVES

Emerging information indicates that glucose metabolism alterations are common after renal transplantation and are associated with carotid atheromatosis. The aims of this study were to investigate the prevalence of different glucose metabolism alterations in stable recipients as well as the factors related to the condition.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A multicenter, cross-sectional study was conducted of 374 renal transplant recipients without pre- or posttransplantation diabetes. A standard 75-g oral glucose tolerance test was performed.

RESULTS

Glucose metabolism alterations were present in 119 (31.8%) recipients: 92 (24.6%) with an abnormal oral glucose tolerance test and 27 (7.2%) with isolated impaired fasting glucose. The most common disorder was impaired glucose tolerance (17.9%), and an abnormal oral glucose tolerance test was observed for 21.5% of recipients with a normal fasting glucose. By multivariate analysis, age, prednisone dosage, triglyceride/high-density lipoprotein cholesterol ratio, and beta blocker use were shown to be factors related to glucose metabolism alterations. Remarkably, triglyceride levels, triglyceride/high-density lipoprotein cholesterol ratio, and the proportion of recipients with impaired fasting glucose were already higher throughout the first posttransplantation year in recipients with a current glucose metabolism alteration as compared with those without the condition.

CONCLUSIONS

Glucose metabolism alterations are common in stable renal transplant recipients, and an oral glucose tolerance test is required for its detection. They are associated with a worse metabolic profile, which is already present during the first posttransplantation year. These findings may help planning strategies for early detection and intervention.

Impact of acute rejection and new-onset diabetes on long-term transplant graft and patient survival

BACKGROUND AND OBJECTIVES

Development of new therapeutic strategies to improve long-term transplant outcomes requires improved understanding of the mechanisms by which these complications limit long-term transplant survival.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The association of acute rejection and new-onset diabetes was determined in the first posttransplantation year with the outcomes of transplant failure from any cause, death-censored graft loss, and death with a functioning graft in 27,707 adult recipients of first kidney-only transplants, with graft survival of at least 1 yr, performed between 1995 and 2002 in the United States.

RESULTS

In multivariate analyses, patients who developed acute rejection or new-onset diabetes had a similar risk for transplant failure from any cause, but the mechanisms of transplant failure were different: Acute rejection was associated with death-censored graft loss but only weakly associated with death with a functioning graft. In contrast new-onset diabetes was not associated with death-censored graft loss but was associated with an increased risk for death with a functioning graft.

CONCLUSIONS

Acute rejection and new-onset diabetes have a similar impact on long-term transplant survival but lead to transplant failure through different mechanisms. The mechanisms by which new-onset diabetes leads to transplant failure should be prospectively studied. Targeted therapeutic strategies to minimize the impact of various early posttransplantation complications may lead to improved long-term outcomes.

New-onset diabetes mellitus in the kidney recipient: diagnosis and management strategies

Advancing care has markedly improved survival after kidney transplantation, leaving patients susceptible to the effects of chronic transplant-associated morbidities. New-onset diabetes mellitus (NODM) is common in kidney recipients, threatening health and longevity by predisposing to microvascular and cardiovascular disease and by reducing graft survival. A strong rationale therefore exists for the aggressive treatment of NODM in kidney recipients to limit these complications. Screening for diabetes should be systematic and should span the pre- and posttransplantation periods. Once NODM is diagnosed in the kidney transplant patient, a comprehensive plan of therapy should be used to achieve treatment targets. As in the general population, treatment includes lifestyle modification and drug therapy as needed, but transplant-specific factors add complexity to the care of kidney recipients. Among these, minimizing immunosuppression-related toxicity without compromising graft outcomes is of paramount importance. Preexisting allograft functional impairment and the potential for significant interactions with immunosuppressive agents mandate that the expanding armamentarium of hypoglycemic agents be used with care. A team-oriented treatment approach that capitalizes on the collective expertise of transplant physicians, diabetologists, nurse-educators, and dieticians will optimize both glycemic control and the overall health of hyperglycemic kidney recipients.

Cardiovascular disease in transplant recipients: current and future treatment strategies

A cardiovascular disease event in a transplant recipient may be the result of a pretransplantation disease process, a direct effect of immunosuppressant medications, or the result of exposure to a variety of traditional and nontraditional risk factors after transplantation. Although the understanding of posttransplantation cardiovascular disease remains incomplete, there is evidence that the impact of posttransplantation cardiovascular disease has been decreased, through increased attention to this problem. In the absence of controlled studies to guide therapy, this review summarizes treatment of cardiovascular disease risk factors for which there is strong evidence of benefit in the nontransplantation setting, observational evidence of a similar risk in transplant recipients, and evidence that treatment can be safely administered to transplant recipients. Putative risk factors for posttransplantation cardiovascular disease for which the current level of evidence is insufficient to support specific treatment recommendations are also discussed. Potential new strategies to decrease the risk for cardiovascular disease events after transplantation in the future, including aggressive pretransplantation risk reduction, individualized treatments to prevent different types of cardiovascular disease, dedicated efforts to reduce cardiovascular disease events during transitions between dialysis and transplantation, and manipulation of immunosuppressant protocols, are also introduced.

Transplante de pâncreas e ilhotas em portadores de diabetes melito

O transplante simultâneo de pâncreas/rim tem indicações específicas, riscos e benefícios. O procedimento, cada vez mais realizado, traz vantagens se comparado ao paciente em diálise, em relação à qualidade de vida, anos de vida ganhos e evolução das complicações crônicas. Se o paciente tiver a opção de realizar o transplante de rim com doador vivo, que apresenta sobrevida semelhante do enxerto e do paciente aos dez anos, o procedimento deverá ser considerado. O transplante de pâncreas após rim, quando efetivo, pode melhorar a evolução das complicações cardiovasculares, mas em contrapartida provoca maior mortalidade nos primeiros meses após a cirurgia. O transplante isolado de pâncreas também ocasiona a maior mortalidade pós-operatória, resultado da complexidade do procedimento e da imunossupressão. O transplante de ilhotas tem sua indicação para um seleto grupo de diabéticos com instabilidade glicêmica.