Risk factors and incidence of posttransplant diabetes mellitus

The Association between CDKAL1 Gene rs10946398 Polymorphism and Post-Transplant Diabetes in Kidney Allograft Recipients Treated with Tacrolimus

Post-transplant diabetes mellitus (PTDM) is a common complication that occurs in kidney transplant patients, increasing the risk of infection, cardiovascular disease and loss of graft function. Currently, factors that increase the risk of this complication are being sought, among them polymorphisms in genes that regulate carbohydrate metabolism and influence pancreatic β-cell function. The aim of this study was to evaluate the association of selected polymorphisms of genes affecting carbohydrate metabolism, such as CDKAL1 rs10946398, GCK rs1799884, GCKR rs780094 and DGKB/TMEM195 rs2191349, with the development of post-transplant diabetes in kidney transplant patients. This study included 201 Caucasian patients after kidney transplantation treated with tacrolimus. An association was observed between the CDKAL1 rs10946398 gene polymorphism and PTDM. Among patients with PTDM, there was an increased prevalence of the CC genotype in the PTDM group compared to the group without PTDM. The chance of PTDM in those with the CC genotype was 2.60 times higher compared to those with the AC + AA genotypes (CC vs. AC + AA OR (95% CI): 2.60 (1.02-6.61), p = 0.040). Multivariate logistic regression analysis showed that advanced age and the CC genotype (rare homozygote) of CDKAL1 rs10946398 were risk factors for the development of PTDM at 1 year after transplantation. There was no statistically significant association between GCK rs1799884, GCKR rs780094 or DGKB/TMEM195 rs2191349 polymorphisms and the development of post-transplant diabetes mellitus in kidney transplant patients. The results of this study suggest that the CDKAL1 rs10946398 CC genotype is associated with the increased risk of PTDM development in patients after kidney graft transplantation treated with tacrolimus.

Characterization, evolution and risk factors of diabetes and prediabetes in a pediatric cohort of renal and liver transplant recipients

BACKGROUND

Hyperglycemia (HG) and prediabetes are rarely sought in pediatric liver (LT) and renal (RT) transplantation, yet their presence indicates a high risk of diabetes and cardiovascular disease. The objectives of our DIABGRAFT study were to retrospectively (rDIABGRAFT) and longitudinally (pDIABGRAFT) characterize HG and (pre)diabetes in a cohort of children with LT or/and RT.

METHODS

We retrospectively analyzed risk factors of HG from 195 children with LT from 2012 to 2019 and twenty children with RT from 2005 to 2019 at Cliniques universitaires Saint-Luc. In addition, we prospectively followed four LT and four RT children to evaluate the evolution of their glucose metabolism.

RESULTS

Our rDIABGRAFT study showed that 25% and 35% of LT and RT children respectively presented transient HG and 20% of RT developed diabetes. The occurrence of HG was associated with the use of glucocorticoids and with acute events as graft rejection and infection. In our pDIABGRAFT cohort, biological markers of diabetes were in the normal range for HbA_1C, fasting glucose and insulin levels. However, oral glucose tolerance test and glucose sensors showed insulin resistance, impaired glucose tolerance and HG in the post-prandial afternoon period.

CONCLUSION

Our study shows that children with LT and RT were more at risk of developing HG when glucocorticoids were required and that HbA_1C and fasting glucose lack sensitivity for early detection of glucose intolerance. Also, measurement of glycemia immediately after the transplantation and in postprandial period is key to detect dysglycemia since insulin resistance prevailed in our cohort.

CLINICALTRIALSGOV ID

NCT05464043.

Effect of Early Steroid Withdrawal on Posttransplant Diabetes Among Kidney Transplant Recipients Differs by Recipient Age

Supplemental Digital Content is available in the text.

Background.

Posttransplant diabetes (PTD), a major complication after kidney transplantation (KT), is often attributable to immunosuppression. The risk of PTD may increase with more potent steroid maintenance and older recipient age.

Methods.

Using United States Renal Data System data, we studied 12 488 adult first-time KT recipients (2010–2015) with no known pre-KT diabetes. We compared the risk of PTD among recipients who underwent early steroid withdrawal (ESW) versus continued steroid maintenance (CSM) using Cox regression with inverse probability weighting to adjust for confounding. We tested whether the risk of PTD resulting from ESW differed by recipient age (18–29, 30–54, and ≥55 y).

Results.

Of 12 488, 28.3% recipients received ESW. The incidence rate for PTD was 13 per 100 person-y and lower among recipients who received ESW (11 per 100 person-y in ESW; 14 per 100 person-y in CSM). Overall, ESW was associated with lower risk of PTD compared with CSM (adjusted hazard ratio [aHR] = _0.720.79_0.86), but the risk differed by recipient age (P_interaction = 0.09 for comparison between recipients aged 18–29 and those aged 30–54; P_interaction = 0.01 for comparison between recipients aged 18–29 and those aged ≥55). ESW was associated with lower risk of PTD among recipients aged ≥55 (aHR = _0.620.71_0.81) and those aged 30–54 (aHR = _0.730.83_0.95), but not among recipients aged 18–29 (aHR = _0.811.18_1.72). Although recipients who received ESW had a higher risk of acute rejection across the age groups (adjusted odds ratio = _1.011.17_1.34), recipients with no PTD had a lower risk of mortality (aHR = _0.580.66_0.74).

Conclusions.

The beneficial association of ESW with decreased PTD was more pronounced among recipients aged ≥55, supporting an age-specific assessment of the risk-benefit balance regarding ESW.

Pharmacogenetics Based Dose Prediction Model for Initial Tacrolimus Dosing in Renal Transplant Recipients

Tacrolimus, an immunosuppressant used in solid organ transplantation, has a narrow therapeutic index and exhibits inter-individual pharmacokinetic variability. Achieving and maintaining a therapeutic level of the drug by giving appropriate doses is crucial for successful immunosuppression, especially during the initial post-transplant period. We studied the effect of CYP3A5, CYP3A4, and ABCB1 gene polymorphisms on tacrolimus trough concentrations in South Indian renal transplant recipients from Kerala to formulate a genotype-based dosing equation to calculate the required starting daily dose of tacrolimus to be given to each patient to attain optimal initial post-transplant period drug level. We also investigated the effect of these genes on drug-induced adverse effects and rejection episodes and looked into the global distribution of allele frequencies of these polymorphisms. One hundred forty-five renal transplant recipients on a triple immunosuppressive regimen of tacrolimus, mycophenolate mofetil, and steroid were included in this study. Clinical data including tacrolimus daily doses, trough levels (C0) and dose-adjusted tacrolimus trough concentration (C0/D) in blood at three time points (day 6, 6 months, and 1-year post-transplantation), adverse drug effects, rejection episodes, serum creatinine levels, etc., were recorded. The patients were genotyped for CYP3A5*3, CYP3A4*1B, CYP3A4*1G, ABCB1 G2677T, and ABCB1 C3435T polymorphisms by the PCR-RFLP method. We found that CYP3A5*3 polymorphism was the single most strongly associated factor determining the tacrolimus C0/D in blood at all three time points (p < 0.001). Using multiple linear regression, we formulated a simple and easy to compute equation that will help the clinician calculate the starting tacrolimus dose per kg body weight to be administered to a patient to attain optimal initial post-transplant period tacrolimus level. CYP3A5 expressors had an increased chance of rejection than non-expressors (p = 0.028), while non-expressors had an increased risk for new-onset diabetes mellitus after transplantation (NODAT) than expressors (p = 0.018). Genotype-guided initial tacrolimus dosing would help transplant recipients achieve optimal initial post-transplant period tacrolimus levels and thus prevent the adverse effects due to overdose and rejection due to inadequate dose. We observed inter-population differences in allele frequencies of drug metabolizer and transporter genes, emphasizing the importance of formulating population-specific dose prediction models to draw results of clinical relevance.

Prevalence and Predictors of "New-onset Diabetes after Transplantation" (NODAT) in Renal Transplant Recipients: An Observational Study

OBJECTIVE

New-onset diabetes after transplantation (NODAT) develops frequently after renal transplant. The study aims at the prevalence of NODAT, predictors for developing it and therapeutic glycemic responses in NODAT.

MATERIALS AND METHODS

Consecutive renal transplant recipients excluding Diabetic Kidney Disease (DKD) or pretransplant diabetes were evaluated. Forty-three out of 250 persons were found to have NODAT. Ninety age-matched transplant recipients from the rest were recruited as control. Fasting blood sugar (FBS), HbA1c, lipid profile, and trough tacrolimus level (T₀) were examined in all. HOMA IR C-peptide and HOMA-beta C-peptide were calculated.

RESULTS

Prevalence of NODAT in renal transplant recipients was 17.2% (43/250). Twenty-four (55.8%) developed early NODAT (<1 year) and 19 (44.2%) developed late NODAT (>1 year). Significantly higher pretransplant body mass index (BMI) (kg/m²) (P < 0.001), waist circumference (WC) (cm) (P < 0.001), pretransplant cholesterol (mg%) (P = 0.04), triglyceride (mg%) (P < 0.001), and FBS (mg%) (P < 0.001) were found in NODAT compared with non-NODAT. Trough tacrolimus (ng/mL) was found to be higher in NODAT (10.2 vs. 5.37, P < 0.001). Though HOMA IR was not found to be different between groups, HOMA-beta C-peptide was low in NODAT compared with non-NODAT (P = 0.03). Predictors of NODAT were WC [odds ratio (OR) = 01.15] and trough tacrolimus level (OR = 1.316). Best cut-off of WC for predicting NODAT was 87.5 cm for male and 83.5 cm for female. Best cut-off of T₀ was 8.5 ng/mL. In NODAT, 9.3% were treated by lifestyle modification, 67.4% by oral hypoglycemic agents, 11.6% by insulin, and 11.6% by combined insulin and oral antidiabetic agents with HbA1c <7%.

CONCLUSION

NODAT in renal transplant recipients is more common in those with higher pretransplant BMI, WC, pretransplant total cholesterol, triglyceride, and FBS. Beta-cell secretory defect is more relevant as etiological factor rather than insulin resistance. Higher WC and trough tacrolimus level above 8.5 ng/mL may be important factors for predicting NODAT.

Genetic and clinic predictors of new onset diabetes mellitus after transplantation

New Onset Diabetes after Transplantation (NODAT) is a frequent complication after solid organ transplantation, with higher incidence during the first year. Several clinical and genetic factors have been described as risk factors of Type 2 Diabetes (T2DM). Additionally, T2DM shares some genetic factors with NODAT. We investigated if three genetic risk scores (w-GRS) and clinical factors were associated with NODAT and how they predicted NODAT development 1 year after transplantation. In both main (n = 725) and replication (n = 156) samples the clinical risk score was significantly associated with NODAT (OR_main: 1.60 [1.36-1.90], p = 3.72*10^-8 and OR_replication: 2.14 [1.39-3.41], p = 0.0008, respectively). Two w-GRS were significantly associated with NODAT in the main sample (OR_{w-GRS 2}:1.09 [1.04-1.15], p = 0.001 and OR_{w-GRS 3}:1.14 [1.01-1.29], p = 0.03) and a similar OR_{w-GRS 2} was found in the replication sample, although it did not reach significance probably due to a power issue. Despite the low OR of w-GRS on NODAT compared to clinical covariates, when integrating w-GRS 2 and w-GRS 3 in the clinical model, the Area under the Receiver Operating Characteristics curve (AUROC), specificity, sensitivity and accuracy were 0.69, 0.71, 0.58 and 0.68, respectively, with significant Likelihood Ratio test discrimination index (p-value 0.0004), performing better in NODAT discrimination than the clinical model alone. Twenty-five patients needed to be genotyped in order to detect one misclassified case that would have developed NODAT 1 year after transplantation if using only clinical covariates. To our knowledge, this is the first study extensively examining genetic risk scores contributing to NODAT development.

Weighted Genetic Risk Scores and Prediction of Weight Gain in Solid Organ Transplant Populations

Background

Polygenic obesity in Solid Organ Transplant (SOT) populations is considered a risk factor for the development of metabolic abnormalities and graft survival. Few studies to date have studied the genetics of weight gain in SOT recipients. We aimed to determine whether weighted genetic risk scores (w-GRS) integrating genetic polymorphisms from GWAS studies (SNP group#1 and SNP group#2) and from Candidate Gene studies (SNP group#3) influence BMI in SOT populations and if they predict ≥10% weight gain (WG) one year after transplantation. To do so, two samples (n_A = 995, n_B = 156) were obtained from naturalistic studies and three w-GRS were constructed and tested for association with BMI over time. Prediction of 10% WG at one year after transplantation was assessed with models containing genetic and clinical factors.

Results

w-GRS were associated with BMI in sample A and B combined (BMI increased by 0.14 and 0.11 units per additional risk allele in SNP group#1 and #2, respectively, p-values<0.008). w-GRS of SNP group#3 showed an effect of 0.01 kg/m² per additional risk allele when combining sample A and B (p-value 0.04). Models with genetic factors performed better than models without in predicting 10% WG at one year after transplantation.

Conclusions

This is the first study in SOT evaluating extensively the association of w-GRS with BMI and the influence of clinical and genetic factors on 10% of WG one year after transplantation, showing the importance of integrating genetic factors in the final model. Genetics of obesity among SOT recipients remains an important issue and can contribute to treatment personalization and prediction of WG after transplantation.

Is basiliximab induction, a novel risk factor for new onset diabetes after transplantation for living donor renal allograft recipients?

AIM

It was found that, by affecting populations of T lymphocytes and regulatory T cells, basiliximab also indirectly affects pancreatic β-cell function and glucose homeostasis.

METHODS

In this prospective observational study, we included all renal transplant recipients from 1 July 2007 to 31 July 2011. The overall incidence of hyperglycaemia (transient hyperglycaemia, impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and new onset diabetes after transplantation (NODAT)) was compared between patients with and without basiliximab induction.

RESULTS

Of the 439 eligible study patients, 105 patients received basiliximab induction and 334 patients did not. Overall hyperglycaemia (transient hyperglycaemia, IFG, IGT and NODAT) was detected in 102/334 (30.5%) patients without induction and 44/105 (41.9%) patients with induction (P = 0.03). Of the 102 patients with hyperglycaemia in patients without basiliximab, 46 (45.1%) patients improved, while only 10 (22.7%) of the 44 patients with basiliximab improved (P = 0.016) at the end of 3 months. Finally, NODAT was observed in 56/334 (16.7%) patients without induction and 102/334 (30.5%) patients with induction. Relative risk of NODAT with basiliximab was 2.3 (95% CI 1.4-3.9) compared to that of patients without induction. Basiliximab and hepatitis C virus infection were independent risk factors for NODAT. Risk of NODAT remained high with basiliximab despite adjusting the acute rejections episodes.

CONCLUSIONS

Basiliximab induction prevents acute rejection; however, it is associated with increased risk of NODAT.

Obesity and metabolic syndrome in kidney transplantation

The epidemic of obesity and metabolic syndrome (MS) contributes to the rapid growth of chronic kidney disease (CKD) and end-stage renal disease (ESRD). There is a reverse epidemiology, known as the "obesity paradox," in ESRD patients receiving maintenance dialysis. Obese patients are routinely referred for kidney transplant, and they have more surgical and medical complications than non-obese patients. However, compared to dialysis, kidney transplant provides a survival benefit for obese patients. After kidney transplant, obese patients tend to gain more body weight, and non-obese patients can develop new-onset obesity/MS. Obesity/MS is not only associated with serious morbidities, but also compromises the long-term graft and patient survival. The immunosuppressive drugs commonly used as maintenance therapy, including corticosteroids, calcineurin inhibitors and mammalian target-of-rapamycin inhibitors, contribute to obesity/MS. Development of novel immunosuppressive drugs free of metabolic adverse effects is needed, so that the full potential and benefits of kidney transplantation can be realized.

The incidence of posttransplantation diabetes mellitus during follow-up in kidney transplant recipients and relationship to Fok1 vitamin D receptor polymorphism

BACKGROUND

Posttransplantation diabetes mellitus (PTDM) is a common, serious complication of kidney transplantation. The purpose of this study was to investigate the incidence of and risk factors for PTDM in relationship to Fok1 vitamin D receptor (VDR) polymorphisms.

METHODS

One hundred five kidney transplant recipients with normal glucose values before transplantation were recruited for this study. All patients underwent fasting plasma glucose (FPG) determinations followed by oral glucose tolerance tests (OGTTs) among normal FPG recipients. Every recipient underwent Fok1 VDR polymorphism analysis using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP).

RESULTS

Among 105 recipients, 16 (15.24%) developed new-onset PTDM within 6 months after kidney transplantation. Compared with 89 non-PTDM recipients, the mean age was significantly higher among recipients with PTDM: 47.81 ± 15.54 vs 36.62 ± 11.43 years (P = .001). Patients treated with tacrolimus were more susceptible to PTDM (56.25% vs 28.09%; P = .027). The distribution frequencies of Fok1 genotypes in this cohort followed the Hardy-Weinberg equilibrium. The frequencies of 3 genotypes (FF/Ff/ff; P = .040) and 2 alleles (F/f; P = .009) differed between the 2 groups. Multivariate analysis by logistic regression showed age older than 40 years (odds ratio, 7.774; P = .005), VDR Fok1 f allele (odds ratio, 11.765; P = .012), and tacrolimus therapy (odds ratio, 7.499; P = .007) to be related to the development of PTDM.

CONCLUSIONS

The incidence of newly diagnosed PTDM in this study was 15.24%. Fok1 VDR polymorphism was a genetic marker predicting PTDM risk. Age older than 40 years and tacrolimus were independent risk factors for PTDM.

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.

Glutathione S-transferase gene polymorphisms are not major risks for susceptibility to posttransplantation diabetes mellitus in Taiwan renal transplant recipients

Glutathione S-transferase (GST) M1 null genotype has been reported playing a significant role in the diabetes mellitus (DM) susceptibility in Turkish population. We investigated whether the GSTM1, GSTA1, and GSTP1 gene polymorphisms are associated with posttransplantation diabetes mellitus (PTDM) in Taiwan. There were 283 renal transplant recipients (RTRs) enrolled. Polymerase chain reaction-restriction fragment length polymorphism was used for the measurement of GSTA1, M1, and P1 genetic polymorphisms. PTDM was diagnosed according to the American Diabetes Association guidelines. Eight-five patients (30%) were diagnosed with PTDM. The averaged posttransplant follow-up period was 77.9 ± 27.2 months. Duration from transplantat to diagnosis of PTDM ranged from 0.2 to 103.1 months (19.2 ± 26.3 months). There were significantly differences between non-DM and PTDM groups in age (50.6 ± 11.0 vs. 54.6 ± 9.36 years, P = 0.005), BMI (22.4 ± 3.6 vs. 24.3 ± 3.8, P<0.001). The distributions of GSTA1, GSTP1, and GSTM1 genotypes alleles were not significantly different between PTDM and non-DM group. Patients carrying the different GSTA1, GSTP1, and GSTM1 genetic and allelic polymorphisms had no differences for the development of PTDM. These overall results suggested a lack of strong association with GSTA1, GSTP1, and GSTM1 genetic polymorphisms to the susceptibility of PTDM in Taiwanese RTRs.

Increased body mass index but not common vitamin D receptor, peroxisome proliferator-activated receptor γ, or cytokine polymorphisms confers predisposition to posttransplant diabetes

CONTEXT

Posttransplant diabetes mellitus (PTDM) is a major complication after solid organ transplantation. The use of corticosteroids and calcineurin inhibitors, especially tacrolimus, are significant risk factors. However, it is not clear what genetic factors modify the risk. Evidence suggests vitamin D deficiency, perturbed glucose homeostasis, and increased inflammation all play roles in the development of diabetes.

OBJECTIVE

To investigate whether common vitamin D receptor (VDR), cytokine, and peroxisome proliferator-activated receptor γ (PPARγ) polymorphisms are correlated with the development of PTDM.

DESIGN

DNA was isolated from the peripheral blood of 51 kidney transplant recipients with PTDM and 72 patients without diabetes pretransplant or posttransplant at the time of follow-up. The genotypes for 5 polymorphisms, 1 each in VDR, PPARγ, INFγ, TGFβ1, and TNF, were determined using direct sequencing. Age, sex, number of acute rejection episodes, follow-up length, ethnicity, body mass index, and the frequency of alleles and genotypes for each polymorphism were compared between the 2 groups.

RESULTS

Body mass index was the only factor that was statistically different between the 2 groups (P  =  .001). The frequency of different alleles and genotypes for each of the 5 polymorphisms did not differ between the 2 groups.

CONCLUSIONS

These results indicate that increased body mass index is a significant risk factor for the development of PTDM. However, none of the genetic polymorphisms studied confer predisposition to PTDM with the current sample size.

Incidence and Risk Factors for Development of New-onset Diabetes after Kidney Transplantation

Introduction: New-onset diabetes after transplantation (NODAT) is an increasingly recognised metabolic complication of kidney transplantation that is associated with increased morbidity and mortality. This study aimed to determine the incidence of NODAT and identify risk factors for development of NODAT among kidney allograft recipients in a single centre. Materials and Methods: We retrospectively reviewed all kidney allograft recipients in our centre between 1998 and 2007. NODAT were determined using criteria as per American Diabetes Association guidelines. Logistic regression analyses were performed to identify predictors of NODAT. Results: Among 388 patients included in the analysis, NODAT was reported in 94 patients (24.2%) after a median follow-up time of 52.1 months. The cumulative incidence of NODAT was 15.8%, 22.8% and 24.5% at 1, 3, and 5 years following transplantation. Seven clinical factors were independent predictors of NODAT: older age, HLA B13 and B15 phenotypes, use of sirolimus, acute rejections, higher pre-transplant and post-transplant (day 1) plasma glucose levels. Patients with NODAT had poorer outcomes in both graft and patient survival. Conclusion: Our study demonstrates a significant risk and burden of NODAT in an Asian transplant population. Risk stratification and aggressive monitoring of blood glucose early post-transplantation is necessary to identify high-risk patients so that appropriate tailoring of immunosuppression and early institution of lifestyle modifications can be implemented. Key words: Diabetes mellitus, Immunosuppression, Kidney transplantation, Metabolic complication, Sirolimus

Tumor necrosis factor alpha promoter polymorphism in posttransplantation diabetes mellitus of renal transplant recipients

Posttransplantation diabetes mellitus (PTDM) is a major complication in renal transplant recipients. Some studies have demonstrated that tumor necrosis factor alpha (TNF-α) expression and its genetic polymorphism are associated with diabetes mellitus. We investigated this association in Asian renal transplant recipients. Polymerase chain reaction-restriction-fragment length polymorphism was used to measure TNF-α G-238A and G-308A gene polymorphisms among 241 nonposttransplantation diabetic subjects and 73 PTDM patients. PTDM patients showed higher values of body weight and body mass index (BMI) than the non-PTDM group. However, no significant association was observed between TNF-α G-238A and TNF-α G-308A polymorphisms with PTDM incidence, gender, age at transplantation, follow-up duration, BMI, or type of immunosuppression.

Association of metabolic syndrome with development of new-onset diabetes after transplantation

BACKGROUND

New-onset diabetes after transplantation (NODAT) is a major posttransplant complication associated with lower allograft and recipient survival. Our objective was to determine whether metabolic syndrome pretransplant is independently associated with NODAT development.

METHODS

We recruited 640 consecutive incident nondiabetic renal transplant recipients from three academic centers between 1999 and 2004. NODAT was defined as the use of hypoglycemic medication, a random plasma glucose level more than 200 mg/dL, or two fasting glucose levels more than or equal to 126 mg/dL beyond 30 days posttransplant.

RESULTS

Metabolic syndrome was common pretransplant (57.2%). NODAT developed in 31.4% of recipients 1 year posttransplant. Participants with metabolic syndrome were more likely to develop NODAT compared with recipients without metabolic syndrome (34.4% vs. 27.4%, P=0.057). Recipients with increasing number of positive metabolic syndrome components were more likely to develop NODAT (metabolic syndrome score prevalence at 1 year: 0 components-0.0%, 1-24.2%, 2-29.3%, 3-31.0%, 4-34.8%, and 5-73.7%, P=0.001). After adjustment for demographics, age by decade (hazard ratio [HR] 1.34 [1.20-1.50], P<0.0001), African American race (HR 1.35 [1.01-1.82], P=0.043), cumulative prednisone dosage (HR 1.18 [1.07-1.30], P=0.001), and metabolic syndrome (HR 1.34 [1.00-1.79], P=0.047) were independent predictors of development of NODAT at 1 year posttransplant. In a multivariable analysis incorporating the individual metabolic syndrome components themselves as covariates, the only pretransplant metabolic syndrome component to remain an independent predictor of NODAT was low high-density lipoprotein (hazard ratio [HR] 1.37 [1.01-1.85], P=0.042).

CONCLUSIONS

Metabolic syndrome is an independent predictor for NODAT and is a possible target for intervention to prevent NODAT. Future studies to evaluate whether modification of metabolic syndrome factors pretransplant reduces NODAT development are needed.

Risk factors and outcomes associated with posttransplant diabetes mellitus in kidney transplant recipients

BACKGROUND

Although our understanding of the risk factors involved in the occurrence of posttransplant diabetes mellitus (PTDM) as well as its outcomes has improved, it still remains incomplete. Our study attempts to analyze the risk factors as well as the outcomes associated with PTDM in the renal transplant patients at the Cleveland Clinic.

METHODS

Our study is a retrospective, case-control study. We screened 209 charts of 217 patients who received single-organ kidney transplant at the Cleveland Clinic between January 1996 and December 1998. PTDM was defined by the American Diabetes Association criteria of either a fasting blood glucose >or=126 mg/dL or random blood sugars >or=200 mg/dL confirmed on a second occasion. Kidney transplant recipients who developed PTDM (cases) were compared with kidney transplant recipients who did not develop diabetes but were matched for the time of transplant (controls).

RESULTS

Forty-nine patients (23%) developed PTDM. The data of 47 cases and 47 controls were analyzed. Age >or=40 years, body mass index >or=30, pretransplant triglyceride levels >150 mg/dL, and presence of graft rejection were significant risk factors for developing PTDM. Smoking was associated with increased risk of PTDM but failed to achieve statistical significance. Compared with controls, PTDM patients had higher risk of cardiovascular disease, infections, and graft rejection.

CONCLUSION

Our results show that PTDM is a significant problem after kidney transplantation, and those who have high risk should be closely monitored after transplant and aggressively treated if they develop diabetes to minimize the risk of complications.

Pre-transplant weight but not weight gain is associated with new-onset diabetes after transplantation: a multi-centre cohort Spanish study

Background. New-onset diabetes after transplantation (NODAT) is associated with poorer outcomes in kidney transplantation (KT). Thus, identification of modifiable risk factors may be crucial for ameliorating the impact of this entity on transplant outcomes. We assessed the relationships between the weight, body mass index (BMI) and weight gain with NODAT.Methods. We retrospectively analysed 2168 KT performed in Spain during 1990, 1994, 1998 and 2002, with a functioning graft after the first year. At 1 year after KT, three groups were considered: (i) NODAT group (n = 215); (ii) impaired fasting glucose (IFG) group (n = 389); (iii) control group (n = 1564).Results. The incidence of NODAT was 10.8%, 9.9% and 10.0% at 3, 12 and 24 months post-transplantation, respectively. Older recipient age (P < 0.0001) and greater use of tacrolimus (P < 0.0001) were observed in NODAT group. Obesity was more frequent in NODAT group (P < 0.0001), but patients with NODAT had a lower weight gain during the first year after KT (P = 0.038). On multivariate analysis, independent risk factors associated with the development of NODAT were: recipient age [odds ratio (OR): 1.060, P = 0.0001], tacrolimus (OR: 1.611, P = 0.005), triglycerides (OR: 1.511, P = 0.018), positive hepatitis C virus (HCV) status (OR: 1.969, P = 0.001) and pre-transplant body mass index (BMI) (OR: 1.135, P = 0.0001), but not the weight gain.Conclusions. BMI, but not the weight gain at 1 year after transplant, is an independent risk factor for NODAT. Tailoring clinical strategies may minimize the impact of this complication.

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.

Genetic modifiers play a substantial role in diabetes complicating cystic fibrosis

CONTEXT

Insulin-requiring diabetes affects 7-15% of teens and young adults, and more than 25% of older adults with cystic fibrosis (CF). Pancreatic exocrine disease caused by CF transmembrane conductance regulator (CFTR) dysfunction underlies the high rate of diabetes in CF patients; however, only a subset develops this complication, indicating that other factors are necessary.

OBJECTIVE

Our objective was to estimate the relative contribution of genetic and nongenetic modifiers to the development of diabetes in CF.

DESIGN/PATIENTS

This was a twin and sibling study involving 1366 individuals at 109 centers in the CF Twin and Sibling Study, from which were derived 68 monozygous twin pairs, 23 dizygous twin pairs, and 588 sibling pairs, all with CF.

MAIN OUTCOME MEASURE

Chronic, insulin-requiring diabetes in the setting of CF, as established using longitudinal clinical and biochemical data, was studied.

RESULTS

About 9% of this predominantly pediatric population (mean age = 15.8 yr) had diabetes. Key independent risk factors identified by regression modeling included having a twin or sibling with CF and diabetes, increasing age, pancreatic exocrine insufficiency or two mutations causing severe CFTR dysfunction, decreased lung function or decreased body mass index, and longer duration of glucocorticoid treatment. The concordance rate for diabetes was substantially higher in monozygous twins (0.73) than in dizygous twins and siblings with CF (0.18; P = 0.002). Heritability was estimated as near one (95% confidence interval 0.42-1.0).

CONCLUSIONS

Diabetes is a frequent complication of CF that is associated with worse outcomes. Although a nongenetic factor (steroid treatment) contributes to risk, genetic modifiers (i.e. genes other than CFTR) are the primary cause of diabetes in CF.

Hyperglycemia during the immediate period after kidney transplantation

BACKGROUND AND OBJECTIVES

Hyperglycemia and new-onset diabetes occurs frequently after kidney transplantation. The stress of surgery and exposure to immunosuppression medications have metabolic effects and can cause or worsen preexisting hyperglycemia. To our knowledge, hyperglycemia in the immediate posttransplantation period has not been studied.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a retrospective, observational study to characterize the prevalence and assess the pharmacologic management of hyperglycemia in kidney transplant recipients who underwent transplantation at our center between June 1999 and December 2006. Data were abstracted from electronic and pharmacy databases.

RESULTS

The study cohort included 424 patients (mean age 51 yr; 58% men; 25% with pretransplantation diabetes). All patients with and 87% without pretransplantation diabetes had evidence of hyperglycemia (bedside glucose >or=200 mg/dl or physician-instituted insulin therapy), whereas the prevalence of hypoglycemia was low (4.5%). Hyperglycemia was sustained throughout hospitalization. All patients with and 66% without pretransplantation diabetes required insulin at hospital discharge. Patients with pretransplantation diabetes were treated primarily with short-acting insulin during the first 24 h after transplantation but were transitioned to long-acting insulin as the hospital stay progressed.

CONCLUSIONS

Investigators have historically attempted to identify hyperglycemia after hospital discharge. Our data indicate that a substantial number of patients without pretransplantation diabetes develop hyperglycemia and require insulin during the hospital phase of their care immediately after kidney transplantation. Prospective studies are needed to delineate factors that contribute to development of new-onset diabetes after transplantation among patients with transient hyperglycemia.

Post-transplant diabetes mellitus in children following renal transplantation

PTDM plays a role in chronic allograft nephropathy and decreases graft and patient survival. Considering the serious outcome of chronic hyperglycemia, the importance of early recognition and the few data in children, in this retrospective analysis we studied the characteristics and risk factors of PTDM in 45 pediatric renal transplant recipients receiving Tac or CyA-based immunosuppression. Fasting blood sampling and OGTT were performed. PTDM has been developed in six patients (13%), while seven children (16%) had IGT, with the overall incidence of a glucose metabolic disorder of 29% in pediatric renal transplants. Patients in the PTDM + IGT group were younger and had higher systolic blood pressure and serum triglyceride level than children with normal glucose tolerance. Multivariate analysis identified Tac treatment, Tac trough level, steroid pulse therapy and family history of diabetes to be associated with the onset of PTDM. In pediatric renal transplants, OGTT and frequent assessment of blood glucose levels might be essential not only in the post-transplant management, but also prior to transplantation, particularly with family history of diabetes. Careful monitoring and modified protocols help to minimize the side effects of Tac and corticosteroids.

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.

Sirolimus is associated with new-onset diabetes in kidney transplant recipients

New-onset diabetes (NOD) is associated with transplant failure. A few single-center studies have suggested that sirolimus is associated with NOD, but this is not well established. With the use of data from the United States Renal Data System, this study evaluated the association between sirolimus use at the time of transplantation and NOD among 20,124 adult recipients of a first kidney transplant without diabetes. Compared with patients treated with cyclosporine and either mycophenolate mofetil orazathioprine, sirolimus-treated patients were at increased risk for NOD, whether it was used in combination with cyclosporine (adjusted hazard ratio [HR] 1.61; 95% confidence interval [CI] 1.36 to 1.90),tacrolimus (adjusted HR 1.66; 95% CI 1.42 to 1.93), or an antimetabolite (mycophenolate mofetil orazathioprine; adjusted HR 1.36; 95% CI 1.09 to 1.69). Similar results were obtained in a subgroup analysis that included the 16,861 patients who did not have their immunosuppressive regimen changed throughout the first posttransplantation year. In conclusion, sirolimus is independently associated with NOD. Given the negative impact of NOD on posttransplantation outcomes, these findings should be confirmed in prospective studies or in meta-analyses of existing trials that involved sirolimus.

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.

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.

Comprehensive management of post-transplant diabetes mellitus: from intensive care to home care

Post-transplant diabetes mellitus (PTDM) is a common complication of solid organ and hematopoietic transplantation. This clinically oriented review article briefly summarizes the pathophysiology of PTDM, then presents a comprehensive clinical approach to diagnosis and therapy. Topics include the key clinical aspects of PTDM screening, diagnosis, and management during all phases following transplantation from the intensive care unit, to the inpatient ward, to the outpatient arena.

Risk factors associated with the onset and progression of posttransplantation diabetes in renal allograft recipients

OBJECTIVE

The aim of this study was to assess the incidence of posttransplantation diabetes mellitus (PTDM) in renal allograft recipients and to investigate factors contributing to the onset and progression of PTDM and its underlying pathogenic mechanism(s).

RESEARCH DESIGN AND METHODS

A total of 77 patients with normal glucose tolerance (NGT) were enrolled in this study. An oral glucose tolerance test was performed 1 week before transplantation and repeated at 1 and 7 years after transplantation.

RESULTS

The overall incidence of PTDM was 39% at 1 year and 35.1% at 7 years posttransplantation. The incidence for each category of PTDM was as follows: persistent PTDM (P-PTDM) (patients who developed diabetes mellitus within 1 year of transplantation and remained diabetic during 7 years), 23.4%; transient PTDM (T-PTDM) (patients who developed diabetes mellitus during the 1st year after transplantation but eventually recovered to have NGT), 15.6%; late PTDM (L-PTDM) (patients who developed diabetes mellitus later than 1 year after transplantation), 11.7%; and non-PTDM during 7 years (N-PTDM7) (patients who did not develop diabetes mellitus during 7 years), 49.3%. Older age (> or = 40 years) at transplantation was a higher risk factor for P-PTDM, whereas a high BMI (> or = 25 kg/m2) and impaired fasting glucose (IFG) at 1 year posttransplantation were higher risk factors for L-PTDM. Impaired insulin secretion rather than insulin resistance was significantly associated with the development of P- and L-PTDM.

CONCLUSIONS

Impaired insulin secretion may be the main mechanism for the development of PTDM. Older age at transplantation seems to be associated with P-PTDM, whereas a high BMI and IFG at 1 year after transplantation were associated with L-PTDM.

Posttransplant diabetes mellitus in liver transplant recipients

CONTEXT

Approximately 20% of liver transplant recipients develop posttransplant diabetes mellitus. Hepatitis C, a leading indication for liver transplantation, has been identified as a risk factor for posttransplant diabetes mellitus and is an observation that is not well described.

OBJECTIVE

To evaluate the incidence of posttransplant diabetes mellitus and risk factors associated with this condition.

DESIGN

A retrospective chart review.

SETTING

A large urban transplant center.

PATIENTS

One hundred fifteen liver transplant recipients who received a transplant between January 1, 1998, and August 31, 2001.

RESULTS

The rate of posttransplant diabetes mellitus, calculated at 3-month intervals in the first year after liver transplantation, ranged from 19.4% to 24.6%, which is similar to the averages reported in most published studies. The cumulative rate of posttransplant diabetes mellitus, which includes all patients who developed this condition during the time studied, was 31.3%. Clinical and demographic factors, including immunosuppression regimens, were similar between patients with and without posttransplant diabetes mellitus. Two risk factors for posttransplant diabetes mellitus were identified: hepatitis C, which was the leading indication for transplantation in this group (54.8%), and cytomegalovirus infection during the first year after transplantation. Other clinical and demographic variables, such as gender, age, ethnicity, rejection episodes, body mass index, and immunosuppression, were not identified as risk factors for posttransplant diabetes mellitus in liver transplant recipients.

The role of proinflammatory cytokine gene polymorphisms for development of insulin resistance after renal transplantation

BACKGROUND

Insulin resistance, a frequent prediabetic metabolic complication after renal transplantation, is generally linked to immunosuppressive drugs including corticosteroids, cyclosporine (CsA) or tacrolimus, as well as to age, cadaveric donors and ethnic factors. Cytokines are known to be inflammation modulatory substances that contribute to metabolic derangements after transplantation. The present study investigated the effects of cytokine gene polymorphisms on insulin resistance in renal transplant recipients.

PATIENTS AND METHODS

Sixty-one renal transplant recipients (37 men, 24 women; mean age: 39.3 +/- 10.8 years) who attended regular clinical visits without a known history of diabetes were enrolled in the study. All patients were on a regimen of steroid, CsA, and mycophenolate mofetil. Venous blood samples were collected for biochemical analyses after an overnight fast at 08:00 pm. CsA trough levels, C-reactive protein, and fibrinogen were also estimated. Additional 10 mL of blood was withdrawn into an ethylenediamine tetraacetic acid-containing tube to determine cytokine genotypes (tumor necrosis factor-alpha [TNF-alpha] -238 G/A, transforming growth factor-beta [TGF-beta] codon 10 -869 T/C). Insulin resistance was calculated by the homeostasis model assessment (HOMA) method using the values of fasting blood glucose (FBG) and insulin levels. Anthropometric indices as well as body height, weight, waist and hip circumferences were measured simultaneously to calculate body mass index (kg/m2) and waist-to-hip ratio. Impaired fasting glucose (IFG) was described as an FBG > or = 110 but < 126 mg/dL.

RESULTS

IFG was detected in 27.9% of this study group. The HOMA index was significantly higher among patients with IFG compared with normal FBG (NoGT) (6.3 +/- 4.5 vs 3.7 +/- 1.5; P = .01). Neither FBG and insulin nor HOMA values correlated with antrophometric, metabolic, or inflammatory parameters. Cytokine genotype allele frequencies, age, sex, immunosuppressive and antihypertensive drug type and doses, CsA trough levels, and donor source (cadaveric/living) were similar for patients with IFG and NoGT. Mutant allele carrier genotypes (AA + GA) for TNF-alpha -238 G/A showed higher fasting insulin (14.0 +/- 7.9 vs 34.1 +/- 17.7 microIU/mL; P = .04) and HOMA (4.01 +/- 2.01 vs 7.95 +/- 5.44; P = .002) levels than GG homozygote subjects. FBG, HOMA, and other metabolic and anthropometric indices were similar between TGF-beta codon 10 -869 T/C genotypes. The daily dose of steroid (mg/d) and A allele frequency for TNF-alpha -238 G/A genotype were significant predictors of HOMA index in linear regression analysis.

CONCLUSION

The present study revealed that beside the daily dose of steroids, TNF-alpha -238 G/A genotype may contribute to insulin resistance in renal transplant recipients. Further investigations may highlight the effects of cytokine gene heterogenity on insulin resistance in those patients.

A study on glucose metabolism in a small cohort of children and adolescents with kidney transplant

Post-transplant diabetes mellitus (PTDM) and impaired glucose tolerance are now considered among the major adverse events following organ transplantation. The present study was aimed at investigating the regulation of glucose metabolism in pediatric recipients of a kidney transplant (KT), receiving tacrolimus or cyclosporine A-based immunosuppression. Twelve subjects, eight males and four females, aged 12.1+/-3.8 yr, and with a mean time from KT of 45.6 months were enrolled in the study. All patients had a basal evaluation of fasting glucose (GF), fasting insulin (IF), C-peptide and glycated hemoglobin (HbA1c) levels. They then underwent oral glucose tolerance test (OGTT), with measurement of blood glucose and insulin concentration. Two children had impaired GF, associated with supernormal HbA1c levels, one patient showed impaired glucose tolerance, none had PTDM. Peripheral insulin resistance, as measured by quantitative insulin sensitivity check index (QUICKI) and homeostasis model assessment estimate of insulin sensitivity (HOMA-IR) index, was enhanced in 3 patients. Subsequently, GF significantly increased with time from transplant (p=0.01), while fasting C-peptide and the area under the curve of insulin correlated with creatinine clearance. In conclusion, our results, although generated in a small sample size, would suggest that long-term follow-up of children receiving a KT should extend to explore the response to oral glucose load and at least the basal measure of insulin response.

New-onset diabetes after liver transplantation

AIM

The impact of new-onset diabetes (NOD) posttransplantation has been underestimated in the past. The aim of this study was to evaluate the incidence of diabetes after liver transplantation.

METHODS

We retrospectively analyzed the incidence of NOD in 899 patients transplanted in our center. According to International Consensus 2003 Guidelines, criteria for diagnosis of diabetes were: fasting plasma glucose > or =126 mg/dL, symptoms of diabetes plus casual plasma glucose concentrations > or =200 mg/dL, and 2-hour plasma glucose levels > or =200 mg/dL during an oral glucose tolerance test. We considered only patients with follow-up over 10 months. We evaluated the risk factors correlated with NOD (age, hepatitis C virus [HCV] positivity, tacrolimus vs cyclosporine, steatosic graft), and the outcomes of diabetic patient and their grafts.

RESULTS

The incidence of NOD was 10.8% (90/830 patients). Sixty nine patients were diabetic before transplantation. Recipient age >45 years (14.7% vs 6.8%, P = .002, OR = 2.4) and HCV positivity (15.5% vs 7.8%, P = .001, OR = 2.2) significantly correlated with NOD. Multivariate analysis confirmed these variables to be independently associated with diabetic risk. Tacrolimus was associated with an increased risk of NOD (16.2% in HCV-negative patients, 25% in HCV-positive patients), but this difference was not statistically significant. Steatotic grafts (>10%) were associated with an increased risk of NOD (28.6% vs 10%, P = .001, OR = 3.6). The outcome of patients and grafts in the group of diabetic patients was not significantly different from all other patients.

CONCLUSIONS

The incidence of NOD was more relevant in patients older than 45 years and/or HCV-positive. A steatotic graft was an important risk factor, and the match with high-risk patients should be avoided.

Free fatty acids are associated with obesity, insulin resistance, and atherosclerosis in renal transplant recipients

BACKGROUND

Insulin resistance (IR) may be implicated in the pathogenesis of atherosclerosis in renal transplant recipients (RTRs) and be contributed to, in part, by free fatty acids (FFAs), produced in excess in centrally obese individuals. The aim of this study was to determine the prevalence of IR and the relationships between FFAs, central obesity, and atherosclerosis in a cohort of prevalent RTRs.

METHODS

Observational data were collected on 85 RTRs (mean age 54 years; 49% male, 87% Caucasian). Fasting serum was analyzed for FFAs, glucose, and insulin; IR was calculated using the homeostasis model assessment (HOMA-IR) score. Vascular structure was assessed by carotid intima-media thickness (IMT) measurement. Linear regression analyses were performed to determine the factors associated with IR and atherosclerosis.

RESULTS

IR occurred in 75% of RTRs, and FFA levels were independently associated with its occurrence (beta: -0.55, 95% CI: -1.02 to -0.07, P = 0.02). Other variables independently associated with IR were male sex, body mass index, central obesity, diabetes, systolic blood pressure and corticosteroid use. There was a significant correlation between FFA levels and IMT (r = 0.3, P=0.01). On multivariate analysis, IMT correlated with elevated FFA (beta: 0.07, 95% CI: 0.02-0.12, P = 0.007), diabetes mellitus (P = 0.05), older age (P < 0.002), and a body mass index >25 kg/m (P = 0.002).

CONCLUSIONS

FFAs are associated with the development of IR and may be involved in the pathogenesis of atherosclerosis in RTRs. Additional studies are required to explore these associations further before considering whether an interventional trial aimed at lowering FFA would be a worthwhile undertaking.

Clinical and Genetic Risk Factors for Posttransplant Diabetes Mellitus in Adult Renal Transplant Recipients Treated with Tacrolimus

BACKGROUND

The present study investigated the incidence of posttransplant diabetes mellitus (PTDM) and calculated the risk of developing PTDM under a tacrolimus-based immunosuppression based on clinical characteristics, tacrolimus pharmacokinetics, and genetic polymorphisms related to tacrolimus pharmacokinetics or diabetes mellitus.

METHODS

Seventy nondiabetic adult kidney recipients were studied. Patients with continuous high plasma glucose levels, over 6.5 mg/dl of hemoglobin A1c, or requiring insulin and/or oral antidiabetic agents for more than 3 months after transplantation 6 months postoperatively were diagnosed as having PTDM. Twelve genomic polymorphisms were assessed.

RESULTS

Six months after transplantation, 10 recipients (14.3%) developed PTDM. Positive risk factors were age (P=0.019) and body mass index (P=0.038). There were no significant differences in acute rejection rate, total steroid doses, tacrolimus pharmacokinetics or its related to genetic polymorphisms between the two groups. The frequency of PTDM was significantly higher in patients with the vitamin D receptor (VDR) TaqI t allele than in those with the TT genotype (P=0.013). On multivariate analysis, age over 50 years (odds ratio 9.28, P=0.003) and the presence of the VDR TaqI t allele (odds ratio 7.05, P=0.048) were correlated with the development of PTDM.

CONCLUSION

The incidence of PTDM was 14.3% in our cohort. Age over 50 years was a risk factor. The presence of the VDR TaqI t allele may also be a risk factor for PTDM, suggesting that genotyping of diabetes-related polymorphisms is a possible method of predicting a patient's risk for developing PTDM and would be a valuable asset in selecting appropriate immunosuppressive regimens for individuals.

Should an oral glucose tolerance test be performed routinely in all renal transplant recipients?

Posttransplantation diabetes (PTD) contributes to cardiovascular disease and graft loss in renal transplant recipients (RTR). Current recommendations advise fasting blood glucose (FBG) as the screening and diagnostic test of choice for PTD. This study sought to determine (1) the predictive power of FBG with respect to 2-h blood glucose (2HBG) and (2) the prevalence of PTD using FBG and 2HBG compared with that using FBG alone, in prevalent RTR. A total of 200 RTR (mean age 52 yr; 59% male; median transplant duration 6.6 yr) who were > 6 mo posttransplantation and had no known history of diabetes were studied. Patients with FBG < 126 mg/dl (7.0 mmol/L; n = 188) underwent an oral glucose tolerance test (OGTT). Receiver operating characteristic analyses evaluated the optimal level of FBG predictive of PTD (2HBG > or = 200 mg/dl [11.1 mmol/L]) and impaired glucose tolerance (IGT; 2HBG 140 to 200 mg/dl [7.8 to 11.0 mmol/L]). An abnormal OGTT was reported in 79 (42%) nondiabetic RTR: PTD (n = 22) and IGT (n = 57). The optimal FBG that was predictive of PTD was 101 mg/dl (5.6 mmol/L; area under the curve 0.70; sensitivity 64%, specificity 67%, positive predictive value 20%, negative predictive value 93%). The optimal FBG that was predictive of IGT was less well defined (area under the curve 0.54). The prevalence of PTD was higher by OGTT than by FBG alone (17 versus 6%; P < 0.001). FBG may not be the optimal screening or diagnostic tool for PTD or IGT in RTR. Consideration should be given to introducing the OGTT as a routine posttransplantation investigation, although the implications of a pathologic OGTT are still to be determined in this population.

Predictive Factors for Development of Diabetes Mellitus Post-Heart Transplant

INTRODUCTION

It is known that there is a high incidence of diabetes mellitus (DM) among heart transplant (HT) patients, which may be up to 30% at 5 years. The presence of DM has been associated with increased morbidity (infections, renal dysfunction, or graft vascular disease), and its development has been related primarily to immunosuppressive therapy. The objective of this study was to determine, in our experience, the presence of predictive variables for the development of DM following HT.

METHODS

We studied 315 consecutive non-DM patients (88.6% men, mean age 51.5 years) who underwent HT in our hospital from November 1987 to May 2003, analyzing all variables that could be related to the development of DM during follow-up. Student t-test and chi(2) test were used for univariate statistical analysis and logistic regression for multivariate analysis.

RESULTS

Of the 315 patients, 64 developed DM (20.3%) during a mean follow-up of 3.3 years. The univariate analysis showed that patients developing DM are older (54.9 +/- 8.7 versus 50.7 +/- 11.8 years, P = .008), have a higher body mass index (BMI) (27.3 +/- 3.8 versus 25.7 +/- 3.7, P = .003), a higher prevalence of HT (37.5% versus 23.5%, P = .023), a lower frequency of urgent HT (9.4% versus 26.2%, P = .004), are more often treated with steroids (85.9% versus 70.1%, P = .011) and tacrolimus (12.5% versus 4.4%, P = .015), and have a higher frequency of rejection episodes (71.2% versus 44.6%, P = .001). Multivariate analysis identified the following as predictive factors for the development of DM: age (OR = 1.04, P = .013), urgent HT (OR = 0.36, P = .031), treatment with tacrolimus (OR = 3.89, P = .012), and number of rejections (OR = 2.34, P = .002).

CONCLUSION

In our population, age, urgent HT (which had a protective effect), treatment with tacrolimus, and number of rejections were independent predictive variables for the development of DM during follow-up.

Obesity is associated with worsening cardiovascular risk factor profiles and proteinuria progression in renal transplant recipients

Obesity is associated with adverse cardiovascular (CV) parameters and may be involved in the pathogenesis of allograft dysfunction in renal transplant recipients (RTR). We sought the spectrum of body mass index (BMI) and the relationships between BMI, CV parameters and allograft function in prevalent RTR. Data were collected at baseline and 2 years on 90 RTR (mean age 51 years, 53% male, median transplant duration 7 years), categorized by BMI (normal, BMI < or = 24.9 kg/m2; pre-obese, BMI 25-29.9 kg/m2; obese, BMI > or = 30 kg/m2). Proteinuria and glomerular filtration rate (eGFR(MDRD)) were determined. Nine percent RTR were obese pre-transplantation compared to 30% at baseline (p < 0.001) and follow-up (25 +/- 2 months). As BMI increased, prevalence of metabolic syndrome and central obesity increased (12 vs 48 vs 85%, p < 0.001 and 3 vs 42 vs 96%, p < 0.001, respectively). Systolic blood pressure, fasting blood glucose and lipid parameters changed significantly with BMI category and over time. Proteinuria progression occurred in 65% obese RTR (23 (13-59 g/mol creatinine) to 59 (25-120 g/mol creatinine)). BMI was independently associated with proteinuria progression (beta 0.01, p = 0.008) but not with changing eGFR(MDRD.) In conclusion, obesity is common in RTR and is associated with worsening CV parameters and proteinuria progression.

New-Onset Diabetes after Kidney Transplantation: An Application of 2003 International Guidelines

BACKGROUND

The 2003 International Consensus Guidelines defined new-onset diabetes after transplantation. This study determined the risk of new-onset diabetes following kidney transplantation using these criteria.

METHODS

Consecutive nondiabetic patients who received kidney transplantation between August 2001 and March 2003 (recent, n=61) and before August 2001 (earlier, n=61) were retrospectively evaluated.

RESULTS

In all, 74% in the recent group and 56% in the earlier group developed diabetes by 1 year posttransplant. Median time to diabetes development was 23 days in the recent vs. 134 days in the earlier group (P=0.0304). Most patients developed diabetes within 60 days after transplantation. Immunosuppression was the strongest correlate of diabetes development; tacrolimus and cyclosporine A treatments were associated with increased risk. The rate of development was also greater when rapamycin was added to tacrolimus, compared to when it was not. The risk was double in African-Americans compared to whites. Age, body mass index, family history of diabetes, and etiology of renal failure did not predict diabetes; however, the mean age of patients was greater than previously reported.

CONCLUSIONS

The majority of patients are at risk of developing new-onset diabetes within a short time after kidney transplantation. The risk may be due to preexisting risk factors, immunosuppressive agents, or older age. The significance of these findings is not clear, but demands appropriate follow-up studies related to glycemia, end-organ complications, and graft function. It remains to be determined whether the 2003 International Consensus Guidelines are adequate to appropriately diagnose diabetes in the posttransplant time period, with special emphasis on the first 3 months.

Is HLA-DR6 a Protective Factor Against Posttransplantation Diabetes Mellitus?

BACKGROUND

Posttransplant diabetes mellitus (PTDM) has several pre- and posttransplant risk factors.

METHODS

The incidence and risk factors of PTDM were retrospectively evaluated in 2117 kidney allograft recipients from June 1984 to March 2004. Type and dosage of immunosuppressive agents, pretransplant weight and human leukocyte antigen (HLA) phenotypes in PTDM patients were compared with 61 matched controls.

RESULTS

Sixty-one cases (2.8%) developed PTDM requiring insulin or oral hypoglycemic therapy, out of which 47.5% were men and 52.5% were women, although only 35% of our overall recipients are women. Onset occurred at a mean of 489 days following transplantation. Patients receiving more than 15 mg/d prednisolone developed PTDM more often than those on less than 15 mg/d (P = .000). Similarly PTDM was more frequent among patients who received more than 300 mg/d cyclosporine compared with those on less than 300 mg/d (P = .015). Mean weight in PTDM cases and controls was 65 +/- 13.4 kg and 57 +/- 13.6 kg, respectively (P = .005). HLA-DR6 was observed in 12.2% of nonaffected subjects but in none of the PTDM group (P = .002). Conversely, HLA-DR8 was seen only in PTDM patients (P = .012). In addition HLA-A26 was more common among PTDM patients (P = .02) and HLA-DR52 more frequent in nonaffected subjects (P = .025).

CONCLUSION

Our findings suggest that female sex, dosages of prednisolone and cyclosporine, pretransplant weight, and genetic factors are associated with an increased risk of PTDM. The rate of PTDM appeared to be independent of weight gain in the first year posttransplant. Protection against PTDM may be afforded by HLA-DR6 and possibly HLA-DR52. Conversely and higher incidence of diabetes has been associated with HLA-DR8 and HLA-A26.

Impact of obesity on renal transplant outcomes

Obesity is a frequent and important consideration to be taken into account when assessing patient suitability for renal transplantation. In addition, posttransplant obesity continues to represent a significant challenge to health care professionals caring for renal transplant recipients. Despite the vast amount of evidence that exists on the effect of pretransplant obesity on renal transplant outcomes, there are still conflicting views regarding whether obese renal transplant recipients have a worse outcome, in terms of short- and long-term graft survival and patient survival, compared with their non-obese counterparts. It is well established that any association of obesity with reduced patient survival in renal transplant recipients is mediated in part by its clustering with traditional cardiovascular risk factors such as hypertension, dyslipidaemia, insulin resistance and posttransplant diabetes mellitus, but what is not understood is what mediates the association of obesity with graft failure. Whether it is the higher incidence of cardiovascular comorbidities jeopardising the graft or factors specific to obesity, such as hyperfiltration and glomerulopathy, that might be implicated, currently remains unknown. It can be concluded, however, that pre- and posttransplant obesity should be targeted as aggressively as the more well-established cardiovascular risk factors in order to optimize long-term renal transplant outcomes.

Incidence and Risk Factors of Clinical Characteristics, Tacrolimus Pharmacokinetics, and Related Genomic Polymorphisms for Posttransplant Diabetes Mellitus in the Early Stage of Renal Transplant Recipients

PURPOSE

Posttransplant diabetes mellitus (PTDM) is an important complication in a tacrolimus (TAC)-based immunosuppressive regimen. The present study investigated the incidence, clinical risk factors, TAC pharmacokinetics (PK), and genomic polymorphisms related to TAC-PK or diabetes mellitus (DM) under the TAC-based immunosuppressive protocol.

PATIENTS AND METHODS

Seventy-one nondiabetic renal allograft recipients transplanted from February 1998 to March 2004 were studied. Patients with over 6.5 mg/dL of hemoglobin A1c on sequential blood samples or requiring insulin or oral antidiabetic agents around 6 months after transplantation were diagnosed as having PTDM.

RESULTS

Six months after transplantation, 10 recipients (14.1%) developed PTDM. The positive risk factors were age (P = .003) and body mass index (P = .035). There were no significant differences in gender distribution, pretransplant dialysis period, dialysis modality, acute rejection rate, total steroid doses, TAC-PK, or its related genomic polymorphisms between the two groups. In the DM-related polymorphisms, the frequency of PTDM was significant higher in patients with the VDR TaqI tt or Tt genotype than in those with the TT genotype (P = .013). After a multivariate analysis, age over 50 years (P = .007, odds ratio 8.92) and the presence of VDR TaqI t allele (P = .043, odds ratio 6.71) were correlated with the development of PTDM.

CONCLUSION

The incidence of PTDM in our series was 14.1%. Age over 50 years was a risk factor. The presence of VDR TaqI t allele might be a risk for PTDM. An association between TAC-PK and development of PTDM was not observed.

Reduced incidence of new-onset diabetes mellitus after renal transplantation with 3-hydroxy-3-methylglutaryl-coenzyme a reductase inhibitors (statins)

Statins have anti-inflammatory effects, modify endothelial function and improve peripheral insulin resistance. We hypothesized that statins influence the development of new-onset diabetes mellitus in renal transplant recipients. The records of all previously non-diabetic adults who received an allograft in Toronto between January 1, 1999 and December 31, 2001 were reviewed with follow-up through December 31, 2002. All patients receiving cyclosporine or tacrolimus, mycophenolate mofetil and prednisone were included. New-onset diabetes was diagnosed by the Canadian Diabetic Association criteria: fasting plasma glucose > or =7.0 mmol/L or 2-h postprandial glucose > or =11.1 mmol/L on more than two occasions. Statin use prior to diabetes development was recorded along with other variables. Cox proportional hazards models analyzing statin use as a time-dependent covariate were performed. Three hundred fourteen recipients met study criteria, of whom 129 received statins. New-onset diabetes incidence was 16% (n = 49). Statins (p = 0.0004, HR 0.238[0.109-0.524]) and ACE inhibitors/ARB (p = 0.01, HR 0.309[0.127-0.750]) were associated with decreased risk. Prednisone dose (p = 0.0001, HR 1.007[1.003-1.010] per 1 mg/d at 3 months), weight at transplant (p = 0.02, HR 1.022[1.003-1.042] per 1 kg), black ethnicity (p = 0.02, HR 1.230[1.023-1.480]) and age > or =45 years (p = 0.01, HR 2.226[1.162-4.261]) were associated with increased diabetes. Statin use is associated with reduced new-onset diabetes development after renal transplantation.

New-onset diabetes after transplantation

For many years new-onset diabetes after transplantation has been recognized as a complication of solid-organ transplantation, although its importance has been greatly underestimated. Studies have shown that the cumulative incidence of this condition in heart transplant recipients may reach 32% at 5 years, similar to that reported in kidney and liver transplant patients. Several factors predispose to increased risk for developing new-onset diabetes after transplantation, including age, ethnicity, family history of diabetes, obesity and immunosuppressive therapy. Corticosteroids are associated with the greatest risk of developing the condition. Tacrolimus is more diabetogenic than cyclosporine in kidney and liver transplant patients, but there are few data reporting the effects of these agents in heart transplant patients. In kidney transplant patients, diabetes is known to be a significant risk factor for cardiovascular disease post-transplant. Although this has yet to be demonstrated clearly in heart transplant patients, evidence suggests that new-onset diabetes after transplantation may play a role in the development of cardiac allograft vasculopathy (CAV). Because CAV is the major limitation to long-term survival in this population, it is clear that efforts should be made to reduce the risk of diabetes and treat this condition appropriately. Management of transplant recipients with new-onset diabetes after transplantation has been assisted by the recent publication of International Consensus Guidelines. The guidelines were developed to establish a standard definition and describe risk factors for new-onset diabetes after transplantation. Use of these guidelines will help to prospectively identify those at risk of developing new-onset diabetes after transplantation so that therapeutic strategies can be individualized early in the treatment regimen. These management approaches should help to lower the risk of new-onset diabetes after heart transplantation and reduce the possible long-term consequences of the condition.

Obesity as an independent predictor of posttransplant diabetes mellitus

BACKGROUND

In the general population, there is a clear association between obesity and type 2 diabetes mellitus. However, the evidence of relationship between body mass index (BMI: weight/height(2)) and the risk of posttransplant diabetes mellitus (PTDM) is inconsistent when studied at a level of single center. The aim of our study was to determine if pretransplant BMI is an independent risk factor for PTDM at our center and to demonstrate the pattern of weight gain in patients who develop PTDM.

METHODS

This is a retrospective analysis of renal allograft recipients at University of Colorado Hospital. The medical records of patients who received a kidney transplant from January 1998 to March 2001 were screened to identify the cases of PTDM. Controls were matched for immunosuppressive regimen, gender, and type of donor. A total of 18 cases and 36 controls were identified.

RESULTS

The incidence of PTDM in our transplant population was 10%. Of these cases, 72% developed PTDM in the first 2 months after transplant, and 38% of them required insulin. On multivariate analysis, BMI was significantly associated with PTDM (adjusted odds ratio 1.22, 95% confidence interval 1.04-1.42) while controlling for number of rejections, age, and other factors. We also noticed that weight gain was significantly lower in patients who developed PTDM after transplantation.

CONCLUSIONS

We conclude that obesity is an independent predictor of PTDM. The weight gain was significantly poor among patients who developed PTDM. Among all the risk factors for PTDM, obesity is the only modifiable risk factor before transplantation. Obese patients should be treated with a less diabetogenic immunosuppressive regimen and be counseled to lose weight before transplant.