Abnormal glucose metabolism and metabolic syndrome in non-diabetic kidney transplant recipients early after transplantation. Transplantation. 2010;89:1034-1039. [PMID: 20130496 DOI: 10.1097/tp.0b013e3181d05a90]

Exploring the nexus: The place of kidney diseases within the cardiovascular-kidney-metabolic syndrome spectrum

Cardiovascular-kidney-metabolic (CKM) syndrome and chronic kidney disease (CKD) are two significant comorbidities affecting a large proportion of the general population with considerable crosstalk. In addition to substantial co-incidence of CKD and CKM syndrome in epidemiological studies, clinical and pre-clinical studies have identified similar pathophysiological pathways leading to both entities. Patients with CKM syndrome are more prone to develop acute kidney injury and CKD, while therapeutic alternatives and their success rates are considerably lower in such patient groups. Nevertheless, the association between CKM syndrome and CKD or ESKD is bidirectional rather than being a cause-effect relationship as patients with CKD are also prone to develop peripheral insulin resistance, high blood pressure, and dyslipidemia. Furthermore, such patients are less likely to receive kidney transplantation in addition to the higher allograft dysfunction risk. We hereby aim to evaluate the association in-between kidney diseases and CKM syndrome, including epidemiological data, pre-clinical studies with pathophysiological pathways, and potential therapeutic perspectives.

Continuous Insulin Therapy to Prevent Post-Transplant Diabetes Mellitus: A Randomized Controlled Trial

Rationale & Objectives

Hyperglycemia is frequently observed early after transplantation and associated with development of post-transplant diabetes mellitus (PTDM). Here, we assessed continuous subcutaneous insulin infusion (CSII) targeting afternoon hyperglycemia.

Study Design

Open-label randomized parallel 3-arm design.

Settings & Participants

In total, 85 kidney transplant recipients without previous diabetes diagnosis were randomized to postoperative CSII therapy, basal insulin, or control.

Interventions

Insulin was to be initiated at afternoon capillary blood glucose level of ≥140 mg/dL (7.8 mmol/L; CSII and basal insulin) or fasting plasma glucose level of ≥200 mg/dL (11.1 mmol/L; control).

Outcomes

Hemoglobin A1c (HbA1c) levels at 3 months post-transplant (primary endpoint). PTDM assessed using oral glucose tolerance test at 12 and 24 months.

Results

CSII therapy lasted until median day 18 and maximum day 88. The median HbA1c value at month 3 was 5.6% (38 mmol/mol) in the CSII group versus 5.7% (39 mmol/mol) in the control group (P = 0.70) and 5.4% (36 mmol/mol) in the basal insulin group (P = 0.02). At months 12 and 24, the odds for PTDM were similar compared with the control group (odds ratios [95% confidence intervals], 0.80 [0.18-3.49] and 0.71 [0.15-3.16], respectively) and the basal insulin group (0.96 [0.18-5.68] and 1.51 [0.24-12.84], respectively). Mild hypoglycemia events occurred in the CSII and the basal insulin groups.

Limitations

This study is limited by outdated insulin pump technology, frequent discontinuations of CSII, a complex protocol, and concerns regarding reliability of HbA1c measurements.

Conclusions

CSII therapy was not superior at reducing HbA1c levels at month 3 or PTDM prevalence at months 12 and 24 compared with the control or basal insulin group.

Early Postoperative Basal Insulin Therapy versus Standard of Care for the Prevention of Diabetes Mellitus after Kidney Transplantation: A Multicenter Randomized Trial

BACKGROUND

Post-transplantation diabetes mellitus (PTDM) might be preventable.

METHODS

This open-label, multicenter randomized trial compared 133 kidney transplant recipients given intermediate-acting insulin isophane for postoperative afternoon glucose ≥140 mg/dl with 130 patients given short-acting insulin for fasting glucose ≥200 mg/dl (control). The primary end point was PTDM (antidiabetic treatment or oral glucose tolerance test-derived 2 hour glucose ≥200 mg/dl) at month 12 post-transplant.

RESULTS

In the intention-to-treat population, PTDM rates at 12 months were 12.2% and 14.7% in treatment versus control groups, respectively (odds ratio [OR], 0.82; 95% confidence interval [95% CI], 0.39 to 1.76) and 13.4% versus 17.4%, respectively, at 24 months (OR, 0.71; 95% CI, 0.34 to 1.49). In the per-protocol population, treatment resulted in reduced odds for PTDM at 12 months (OR, 0.40; 95% CI, 0.16 to 1.01) and 24 months (OR, 0.54; 95% CI, 0.24 to 1.20). After adjustment for polycystic kidney disease, per-protocol ORs for PTDM (treatment versus controls) were 0.21 (95% CI, 0.07 to 0.62) at 12 months and 0.35 (95% CI, 0.14 to 0.87) at 24 months. Significantly more hypoglycemic events (mostly asymptomatic or mildly symptomatic) occurred in the treatment group versus the control group. Within the treatment group, nonadherence to the insulin initiation protocol was associated with significantly higher odds for PTDM at months 12 and 24.

CONCLUSIONS

At low overt PTDM incidence, the primary end point in the intention-to-treat population did not differ significantly between treatment and control groups. In the per-protocol analysis, early basal insulin therapy resulted in significantly higher hypoglycemia rates but reduced odds for overt PTDM-a significant reduction after adjustment for baseline differences-suggesting the intervention merits further study.Clinical Trial registration number: NCT03507829.

Onset and progression of diabetes in kidney transplant patients receiving everolimus or cyclosporine therapy: an analysis of two randomized, multicenter trials

Background

Conversion from calcineurin inhibitor (CNI) therapy to a mammalian target of rapamycin (mTOR) inhibitor following kidney transplantation may help to preserve graft function. Data are sparse, however, concerning the impact of conversion on posttransplant diabetes mellitus (PTDM) or the progression of pre-existing diabetes.

Methods

PTDM and other diabetes-related parameters were assessed post hoc in two large open-label multicenter trials. Kidney transplant recipients were randomized (i) at month 4.5 to switch to everolimus or remain on a standard cyclosporine (CsA)-based regimen (ZEUS, n = 300), or (ii) at month 3 to switch to everolimus, remain on standard CNI therapy or convert to everolimus with reduced-exposure CsA (HERAKLES, n = 497).

Results

There were no significant differences in the incidence of PTDM between treatment groups (log rank p = 0.97 [ZEUS], p = 0.90 [HERAKLES]). The mean change in random blood glucose from randomization to month 12 was also similar between treatment groups in both trials for patients with or without PTDM, and with or without pre-existing diabetes. The change in eGFR from randomization to month 12 showed a benefit for everolimus versus comparator groups in all subpopulations, but only reached significance in larger subgroups (no PTDM or no pre-existing diabetes).

Conclusions

Within the restrictions of this post hoc analysis, including non-standardized diagnostic criteria and limited glycemia laboratory parameters, these data do not indicate any difference in the incidence or severity of PTDM with early conversion from a CsA-based regimen to everolimus, or in the progression of pre-existing diabetes.

Trial registration

clinicaltrials.gov, NCT00154310 (registered September 2005) and NCT00514514 (registered August 2007); EudraCT (2006-007021-32 and 2004-004346-40).

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1031-1) contains supplementary material, which is available to authorized users.

Association of Inflammation prior to Kidney Transplantation with Post-Transplant Diabetes Mellitus

BACKGROUND/OBJECTIVE

Post-transplant diabetes mellitus (PTDM) is both common and associated with poor outcomes after kidney transplantation. Our objective was to examine relationships of uremia-associated inflammation and adiponectin with PTDM.

METHODS

Nondiabetic kidney transplant patients were enrolled with donor controls. Inflammatory cytokines and adiponectin were measured before and after transplantation. Adipose tissue was obtained for gene expression analysis. Glucose transport was quantified in vitro in C2C12 cells following cytokine exposure. The patients were monitored up to 12 months for PTDM.

RESULTS

We studied 36 controls and 32 transplant patients, of whom 11 (35%) developed PTDM. Compared to controls, plasma TNFα, IL-6, MCP-1, and CRP levels were higher in transplant patients (p < 0.01). In multivariable analysis, TNFα plasma levels before transplantation were associated with development of PTDM (OR = 2.03, p = 0.04). Visceral adipose tissue TNFα mRNA expression was higher in transplant patients than controls (fold change 1.33; p < 0.05). TNFα mRNA expression was also higher in patients who developed PTDM than in those who did not (fold change 1.42; p = 0.05), and adiponectin mRNA expression was lower (fold change 0.48; p < 0.05). The studies on the C2C12 cells demonstrated an increase in glucose uptake following exposure to adiponectin and no significant change after exposure to TNFα alone. Concomitant TNFα and adiponectin exposure blunted adiponectin-induced glucose uptake (11% reduction; p < 0.001).

CONCLUSION

Our in vitro and clinical observations suggest that TNFα could contribute to PTDM through an effect on adiponectin. Our study proposes that inflammation is involved in glucose regulation after kidney transplantation.

New-onset diabetes mellitus after renal transplantation

BACKGROUND AND AIM

Diabetes mellitus is a very common metabolic disease with a rising incidence. It is both a leading cause of chronic renal disease and one of the most serious comorbidities in renal transplant recipients. New-onset diabetes after renal transplantation (NODAT) is associated with poor graft function, higher rates of cardiovascular complications and a poor prognosis. The aim of this paper is to review current knowledge of NODAT including risk factors, diagnosis and management.

METHODS

A MEDLINE search was performed to retrieve both original and review articles addressing the epidemiology, risk factors, screening and management of NODAT. We also focused on microRNAs as potential biomarkers of NODAT.

RESULTS AND CONCLUSION

Understanding the risk factors (both modifiable-e.g. obesity, viruses, and unmodifiable-e.g. age, genetics) may help reduce the incidence and impact of NODAT using pre- and post-transplant management. This can lead to better long-term graft function and general transplant success.

Dysglycemia after renal transplantation: Definition, pathogenesis, outcomes and implications for management

New-onset diabetes after transplantation (NODAT) is major complication following renal transplantation. It commonly develops within 3-6 mo post-transplantation. The development of NODAT is associated with significant increase in risk of major cardiovascular events and cardiovascular death. Other dysglycemic states, such as impaired glucose tolerance are also associated with increasing risk of cardiovascular events. The pathogenesis of these dysglycemic states is complex. Older recipient age is a consistent major risk factor and the impact of calcineurin inhibitors and glucocorticoids has been well described. Glucocorticoids likely cause insulin resistance and calcineurin inhibitors likely cause β-cell toxicity. The impact of transplantation in incretin hormones remains to be clarified. The oral glucose tolerance test remains the best diagnostic test but other tests may be validated as screening tests. Possibly, NODAT can be prevented by administering insulin early in patients identified as high risk for NODAT. Once NODAT has been diagnosed altering immunosuppression may be acceptable, but creates the difficulty of balancing immunological with metabolic risk. With regard to hypoglycemic use, metformin may be the best option. Further research is needed to better understand the pathogenesis, identify high risk patients and to improve management options given the significant increased risk of major cardiovascular events and death.

Sitagliptin might be a favorable antiobesity drug for new onset diabetes after a renal transplant

OBJECTIVES

The aim of this study was to evaluate the effectiveness of sitagliptin, alone or in combination with metformin, in kidney transplant patients with newly diagnosed new-onset diabetes mellitus after transplant who had inadequate glycemic control, compared with a group of patients receiving insulin glargine with special emphasis on weight gain.

MATERIALS AND METHODS

Newly diagnosed renal transplant patients with new-onset diabetes mellitus after a transplant was defined by a blood glucose ≥ 11.1 mmol/L after an oral glucose tolerance test were examined. They were treated with standard immunosuppression composed of triple therapy with tacrolimus or cyclosporine, mycophenolate mofetil or azathioprine, and prednisone. They had stable graft function for more than 6 months after the transplant.

RESULTS

Patients with new-onset diabetes mellitus after transplant (n=28) whose glycemia was not controlled adequately with oral hypoglycemic agents (either alone or in combination) received oral sitagliptin 100 mg once daily in addition to existing therapy for 12 weeks. Patients who received insulin glargine as add-on therapy (n=17) served as the control group. Data analyses included glycated hemoglobin, fasting plasma glucose, lipid profile, body weight, and the occurrence of hypoglycemia. We found significant reductions in glycated hemoglobin and fasting plasma glucose values after 12 weeks of additional sitagliptin therapy that were comparable to those with insulin glargine. While the addition of stagliptin resulted in a small weight loss (0.4 kg), the addition of insulin glargine resulted in a weight gain (0.8 kg). The overall incidence of adverse experiences was low and generally mild in both groups.

CONCLUSIONS

In a group of renal transplant recipients with new-onset diabetes mellitus after a transplant in whom glycemia was not controlled adequately by oral hypoglycemic agents, the addition of sitagliptin helped to achieve glycemic control similar to insulin glargine but with a marginal weight advantage.

The impact of abnormal glucose regulation on arterial stiffness at 3 and 15 months after kidney transplantation

BACKGROUND

Post-transplant diabetes mellitus (PTDM) has been associated with an increased risk of cardiovascular disease (CVD) mortality following kidney transplantation, but the association between pre-diabetes (i.e. impaired fasting glucose and impaired glucose tolerance) and CVD mortality remains unclear. The aim of this study was to assess the association between abnormal glucose regulation and arterial stiffness at 3 and 15 months post-transplantation.

METHODS

This is a single-centre prospective cohort study of 83 non-diabetic kidney transplant recipients who received a kidney transplant between 2008 and 2011. All patients underwent an oral glucose tolerance test (OGTT - categorised as normal, pre-diabetes or PTDM) and non-invasive measurements of arterial stiffness (aortic pulse wave velocity [PWV] and augmentation index [AIx]) 3 months post-transplantation. A sub-set of patients had repeat OGTT (n = 33) and arterial stiffness measurements (n = 28) at 15 months post-transplant.

RESULTS

Of the 83 patients, 52% (n = 43) had normal glucose regulation, 31% (n = 26) had pre-diabetes and 17% (n = 14) developed PTDM. Compared with recipients with normal glucose regulation, recipients with PTDM (adjusted β = 5.61, 95% confidence interval [CI] 0.09 to 11.13, p = 0.047) but not those with pre-diabetes (adjusted β = 3.23, 95% CI -1.05 to 7.51, p = 0.137) had significantly higher AIx 3 months after transplantation. No association was found between glucose regulation and PWV at 3 months after transplantation. There was no association between glucose regulation at 3 or 15 months and AIx and PWV at 15 months in a subset of recipients.

CONCLUSIONS

Early onset PTDM is associated with increased systemic vascular stiffness (AIx) but not regional stiffness of large arteries (PWV) suggesting that small vessel dysfunction may be the earliest vascular change seen with PTDM. Thus, measurements of arterial stiffness after transplantation may assist in more accurately stratifying future CVD risk of kidney transplant recipients.

Metabolic risk factors and long-term graft function after paediatric renal transplantation

The aim of this study was to evaluate metabolic risk factors and their impact on long-term allograft function in paediatric renal transplant (RTx) patients. We reviewed the medical records of 210 RTx patients who underwent transplantation at a median age of 4.5 years (range 0.7-18.2) and a median follow-up of 7.0 years (range 1.5-18.0). Data on lipid and glucose metabolism, uric acid levels, weight and blood pressure were collected up to 13 years post-RTx, and the findings were correlated with the measured glomerular filtration rate (GFR). Beyond the first year, GFR showed gradual deterioration with a mean decline of 2.4 ml/min/1.73 m(2)/year. Metabolic syndrome, overweight, hypertension and type 2 diabetes were diagnosed in 14-19%, 20-23%, 62-87% and 3-5% of the patients, respectively. These entities showed only mild association with the concomitant or long-term GFR values. Dyslipidaemia was common and hypertriglyceridaemia associated with a lower GFR at 1.5 and 5 years post-RTx (P = 0.008 and P = 0.017, respectively). Similarly, hyperuricaemia was frequent and associated significantly with GFR (P < 0.001). Except for hyperuricaemia and hypertriglyceridaemia, metabolic risk factors beyond the first postoperative year associated modestly with the long-term kidney graft function in paediatric RTx patients.

New-onset diabetes after transplantation (NODAT): an evaluation of definitions in clinical trials

BACKGROUND

New-onset diabetes after transplantation (NODAT) occurs commonly. Prior NODAT definitions have been inconsistent. Based on the American Diabetic Association criteria, we propose a new approach to defining NODAT.

METHODS

Analysis of 1416 at-risk transplant recipients was performed. Data from three de novo Astellas registration transplant studies (two kidney and one liver) evaluated NODAT in 634 at-risk patients receiving tacrolimus, 630 at-risk patients receiving tacrolimus extended release, and 152 at-risk patients receiving cyclosporine. NODAT was defined as a composite endpoint consisting of first occurrence of one of four parameters: (i) two fasting plasma glucose levels ≥ 126 mg/dL (≥ 7.0 mmol/L) ≥ 30 days apart, (ii) oral hypoglycemic agent use for ≥ 30 consecutive days, (iii) insulin therapy for ≥ 30 consecutive days, and (iv) hemoglobin A1c ≥ 6.5%. We evaluated each of the above parameters, as well as the composite endpoint, in an attempt to establish an appropriate clinical approach to the diagnosis of NODAT.

RESULTS

The composite definition results in a 1-year NODAT incidence of 30% to 37% in kidney and 44% to 45% in liver transplant recipients treated with tacrolimus. NODAT incidence was significantly higher with tacrolimus than cyclosporine; there was no difference between the two tacrolimus formulations.

CONCLUSIONS

Based on these analyses, the proposed composite definition for NODAT, incorporating broader criteria, is recommended for clinical trials. Appropriate definitions of NODAT allow for a better understanding of the incidence of this complication and may result in earlier initiation of therapy with improved long-term outcomes.

Glucose metabolism after renal transplantation

OBJECTIVE

We determined prevalence, risk factors, phenotype, and pathophysiological mechanism of new-onset diabetes after transplantation (NODAT) to generate strategies for optimal pharmacological management of hyperglycemia in NODAT patients.

RESEARCH DESIGN AND METHODS

Retrospective cohort study comparing demographics, laboratory data, and oral glucose tolerance test (OGTT)-derived metabolic parameters from kidney transplant recipients versus subjects not receiving transplants.

RESULTS

Among 1,064 stable kidney transplant recipients (≥ 6 months posttransplantation), 113 (11%) had a history of NODAT and 132 (12%) had pretransplant diabetes. In the remaining patients, randomly assigned OGTTs showed a high prevalence of abnormal glucose metabolism (11% diabetes; 32% impaired fasting glucose, impaired glucose tolerance, or both), predominantly in older patients who received tacrolimus as the primary immunosuppressant. Compared with 1,357 nontransplant subjects, stable kidney transplant recipients had lower basal glucose, higher glycated hemoglobin, lower insulin secretion, and greater insulin sensitivity in each of the three subgroups, defined by OGTT 2-h glucose (<140, 140-199, ≥ 200 mg/dL). These findings were reinforced in linear spline interpolation models of insulin secretion and sensitivity (all P < 0.001) and in another regression model in which the estimated oral glucose insulin sensitivity index was substantially higher (by 79-112 mL/min m(2)) for transplant versus nontransplant subjects despite adjustments for age, sex, and BMI (all P < 0.001).

CONCLUSIONS

Glucose metabolism differs substantially between kidney transplant recipients and nontransplant controls. Because impaired insulin secretion appears to be the predominant pathophysiological feature after renal transplantation, early therapeutic interventions that preserve, maintain, or improve β-cell function are potentially beneficial in this population.

Diagnosis, management and treatment of glucometabolic disorders emerging after kidney transplantation: a position statement from the Nordic Transplantation Societies

After successful solid organ transplantation, new-onset diabetes (NODAT) is reported to develop in about 15-40% of the patients. The variation in incidence may partly depend on differences in the populations that have been studied and partly depend on the different definitions of NODAT that have been used. The diagnosis was often based on 'the use of insulin postoperatively', 'oral agents used', random glucose monitoring and a fasting glucose value between 7 and 13 mmol/l (126-234 mg/dl). Only few have used a 2-h glucose tolerance test performed before transplantation. There is a huge variation in the literature regarding risk factors for developing NODAT. They can be divided into factors related to glucose metabolism or to patient demographics and the latter into modifiable and nonmodifiable. Screening for risk factors should start early and be re-evaluated while being on the waitlist. Patients on the waiting list for renal transplantation and transplanted patients share many characteristics in having hyperglycaemia, disturbed insulin secretion and increased insulin resistance. We present guidelines for early risk factor assessment and a screening/treatment strategy for disturbed glucose metabolism, both before and after transplantation. The aim was to avoid the increased cardiovascular disease and mortality rates associated with NODAT.

Metabolic syndrome, vitamin D deficiency and hypoadiponectinemia among nondiabetic patients early after kidney transplantation

BACKGROUND AND AIMS

Metabolic syndrome (MetS) is common among kidney transplant patients. We studied the relationship between MetS, vitamin D deficiency/insufficiency and hypoadiponectinemia early posttransplantation and their impact on clinical outcomes.

METHODS

Seventy-four previously nondiabetic kidney transplant patients were enrolled in a prospective cohort study between February and November 2008. Participants underwent a 2-hour oral glucose tolerance test and had their plasma levels of 25-hydroxyvitamin D (25[OH]D), adiponectin, insulin, intact parathyroid hormone and lipids measured at 11 weeks posttransplantation. Clinical events including cardiovascular events, new-onset diabetes after transplantation, acute rejection, graft loss and death were recorded during the follow-up to December 2012.

RESULTS

Thirty-four study patients (45.9%) had MetS. Patients with MetS had lower plasma concentrations of 25[OH]D (20.5 ± 7.2 vs. 24.8 ± 11.1 ng/ml, p = 0.049) and adiponectin (8.2 ± 4.5 vs. 14.6 ± 8.0 μg/ml, p < 0.0001) early on, and higher composite clinical event rate (61.8 vs. 27.5%, p = 0.003) during the follow-up. Multivariate analysis showed that the presence of MetS early after transplantation was independently associated with 25[OH]D deficiency/insufficiency (OR: 14.0, 95% CI: 1.8, 107.5; p = 0.011), depressed plasma adiponectin levels (β -6.39, r(2) 0.195, p < 0.0001) and increased risk for clinical events (OR: 5.6, 95% CI: 1.9, 16.5; p = 0.002).

CONCLUSION

Kidney transplant patients with MetS early after transplantation had lower levels of 25[OH]D and adiponectin, and unfavorable clinical outcomes.

Clinical diagnosis of metabolic syndrome: predicting new-onset diabetes, coronary heart disease, and allograft failure late after kidney transplant

Metabolic syndrome is associated with coronary heart disease (CHD) and new-onset diabetes after kidney transplant (NODAT). Using data collected from transplant centers worldwide for the Patient Outcomes in Renal Transplantation study, we examined associations of metabolic syndrome (n = 2253 excluding recipients with diabetes pretransplant), CHD (n = 2253), and NODAT (n = 1840 further excluding recipients with diabetes in the first year post-transplant), with the primary outcome of allograft failure. We assessed risk factors associated with secondary outcomes of metabolic syndrome, NODAT, and CHD after adjusting for type of baseline immunosuppression and transplant center effects. Metabolic syndrome prevalence was 39.8% at 12-24 months post-transplant and 35.4% at 36-48 months. Metabolic syndrome was independently associated with NODAT (hazard ratio 3.46, 95% confidence interval 2.40-4.98, P < 0.0001), CHD (2.03, 1.16-3.52, P = 0.013), and allograft failure (1.36, 1.03-1.79, P = 0.028). Allograft failure occurred in 218 patients (14.6%). After adjustment for metabolic syndrome, NODAT (1.63, 1.18-2.24, P = 0.003) and CHD (5.48, 3.27-9.20, P < 0.0001) remained strongly associated with increased risk of allograft failure. Metabolic syndrome, NODAT, and CHD are risk factors for allograft failure. NODAT and CHD are risk factors for allograft failure, independent of metabolic syndrome.

Early basal insulin therapy decreases new-onset diabetes after renal transplantation

No effective interventions to reduce risk for new-onset diabetes after transplantation (NODAT), a condition associated with postoperative hyperglycemia and reduced patient and graft survival, have been established. In this 1-year, proof-of-concept clinical trial, we randomly assigned 50 renal transplant recipients to immediate-postoperative isophane insulin for evening blood glucose ≥140 mg/dl (treatment group) or short-acting insulin and/or oral antidiabetic agents for blood glucose ≥180-250 mg/dl (standard-of-care control group). We included only patients without a history of diabetes who received tacrolimus. By the third postoperative evening, all patients in the treatment group had blood glucose ≥140 mg/dl and were subsequently treated with basal insulin; during the first 3 weeks after transplantation, the mean ± SD daily insulin dosage was 17±11 IU/d. Among controls, 23 (92%) of 25 had blood glucose ≥200 mg/dl and 18 (72%) of 25 received standard-of-care antihyperglycemic treatment. Asymptomatic hypoglycemia occurred five times in the treatment group and once in the control group. Throughout follow-up, the treatment group had 73% lower odds of NODAT (odds ratio, 0.27) than the control group, and hemoglobin A1c was on average 0.38% lower in the treatment group than the control group. Twelve months after transplantation, all patients in the treatment group were insulin-independent, whereas 7 (28%) of 25 controls required antidiabetic agents. The groups did not differ for insulin sensitivity, but the treatment group showed better β-cell function throughout the 1-year follow-up. In conclusion, this study suggests regimens that include basal insulin significantly reduce the odds for NODAT after renal transplantation, presumably via insulin-mediated protection of β cells.

Prevention of cardiovascular disease in adult recipients of kidney transplants

Although advances in immunosuppression, tissue typing, surgery, and medical management have made transplantation a routine and preferred treatment for patients with irreversible renal failure, successful transplant recipients have a greatly increased risk of premature mortality because of cardiovascular disease and malignancy compared with the general population. Conventional cardiovascular risk factors such as hyperlipidaemia, hypertension, and diabetes are common in transplant recipients, partly because of the effects of immunosuppressive drugs, and are associated with adverse outcomes. However, the natural history of cardiovascular disease in such recipients differs from that in the general population, and only statin therapy has been studied in a large-scale interventional trial. Thus, the management of this disease and the balance between management of conventional risk factors and modification of immunosuppression is complex.

Incidence and risk factors for the metabolic syndrome and posttransplant diabetes in renal transplant recipients taking tacrolimus

OBJECTIVES

We investigated the incidence and risk factors for the metabolic syndrome (MS) and posttransplant diabetes mellitus (PTDM) among renal transplant recipients on tacrolimus-based immunosuppressive regimens during the first year posttransplant. In addition, we studied the relationship between MS and PTDM with transplant renal function at 1 year.

METHODS

We included the 100 patients who received a renal transplant in our unit between January 2007 and June 2008, collecting demographic, clinical and biochemical characteristics at 1, 6, and 12 months posttransplantation. We excluded 15% of patients with pretransplantation diabetes. MS was defined according to the National Cholesterol Education Program criteria and PTDM according to World Health Organization criteria. Insulin resistance at one year posttransplant was measured using the homeostasis model assessment (HOMA) index.

RESULTS

Insulin therapy was required in 46% of patients during the first hospitalization and hyperglycemia was present in 65% of the cases. The incidence of PTDM decreased throughout the first year posttransplant, namely, 44%, 24%, and 13% at 1, 6, and 12 months, respectively. The incidence of MS increased to 33%, 48% and 50% at 1, 6, and 12 months, respectively. Age, body mass index, plasma fasting glucose levels at 1 month posttransplant, and pretransplant fasting triglyceridemia predicted PTDM. Rejection and in-patient hyperglycemia predicted MS. PTDM and MS were closely correlated (P=.004). The HOMA index was higher among patients with MS than other subjects at 1 year posttransplant: 3.2 (1.2) versus 2.3 (0.9; P=.035). Neither PTDM nor MS was associated with impaired plasma creatinine levels at 1 year after kidney transplantation.

CONCLUSION

There was an high incidence of PTDM and MS among kidney transplant recipients treated with tacrolimus as the main immunosuppressive agent. The HOMA index was a good test of insulin resistance in this population. Screening and treatment of risk factors may avoid the development of these entities, which are related to poor cardiovascular outcomes.

New-onset diabetes after transplantation: risk factors and clinical impact

With improvements in patient and graft survival, increasing attention has been placed on complications that contribute to long-term patient morbidity and mortality. New-onset diabetes after transplantation (NODAT) is a common complication of solid-organ transplantation, and is a strong predictor of graft failure and cardiovascular mortality in the transplant population. Risk factors for NODAT in transplant recipients are similar to those in non-transplant patients, but transplant-specific risk factors such as hepatitis C (HCV) infection, corticosteroids and calcineurin inhibitors play a dominant role in NODAT pathogenesis. Management of NODAT is similar to type 2 diabetes management in the general population. However, adjusting the immunosuppressant regimen to improve glucose tolerance must be weighed against the risk of allograft rejection. Lifestyle modification is currently the strategy with the least risk and the most benefit.

ENPP1/PC-1 K121Q and other predictors of posttransplant diabetes

Diabetes mellitus is a major cause of morbidity and mortality among transplanted patients. This study evaluated the role of the ENPP1 K121Q polymorphism and other variables known to affect diabetes risk in 115 nondiabetic and unrelated patients who underwent kidney transplant at our institution and had consented for use of genetic material (30% whites, 48% blacks, and 22% Hispanics). Thirty-six of these patients (30%) developed posttransplant diabetes mellitus (PTDM) within 1 year of observation from transplant. Black race, ENPP1 K121Q polymorphism, age, body mass index (BMI), and immunosuppressive medications were found to have the strongest associations with PTDM in the logistic regression and receiver operator characteristic (ROC) analysis. However, because ENPP1 K121Q is more common in Hispanics and in blacks, who also have higher PTDM prevalence, the studied genetic polymorphism did not exert independent predictive effect, whereas ethnicity, specifically black versus non-black, was the most robust predictor of PTDM. The model with the largest ROC area under the curve (AUC) of 0.80 was comprised of black/non-black, age, BMI, and tacrolimus treatment as significant predictors. A reduced model containing only ethnicity (black/non-black) and age as predictors yielded similar results (ROC AUC 0.78). We conclude that black race and age are major and not modifiable risk factors for PTDM. The specific role of ENPP1 K121Q on ethnic susceptibility to PTDM deserves further investigation in larger cohorts of transplanted patients.