Glycaemic control and graft loss following renal transplantation

Safety and Efficacy of Long-Term Administration of Dipeptidyl peptidase IV Inhibitors in Patients With New Onset Diabetes After Kidney Transplant

OBJECTIVES

The appearance of new onset diabetes is common after kidney transplant. Treatment options are limited because of renal function-related contraindications, interactions with immunosuppressive drugs, and side effects. We investigated the long-term safety and efficacy of dipeptidyl peptidase IV inhibitors in renal transplant recipients with new onset diabetes.

MATERIALS AND METHODS

We treated 12 patients with dipeptidyl peptidase IV inhibitors, and 5 patients received insulin monotherapy as initial treatment of new onset diabetes after kidney transplant. All patients were followed for 12 months after diagnosis. Glycosylated hemoglobin A1c, estimated glomerular filtration rate (Chronic Kidney Disease Epidemiology Collaboration equation), plasma immunosuppressive trough levels, serum lipids, blood pressure, and body weight were measured during outpatient visits. Effects of dipeptidyl peptidase IV inhibitors and insulin on the aforementioned parameters were measured to compare values at time of diagnosis versus mean values of the last 6 months of follow-up.

RESULTS

Patients were treated with linagliptin (4 patients), sitagliptin (4 patients), vildagliptin (2 patients), and alogliptin (2 patients). Patients had a mean age of 59.4 ± 12 years and a mean glycosylated hemoglobin A1c of 6.6% at diagnosis, which was decreased to 6.1% (P = .03) at 1 year of follow-up. Renal function remained stable, and plasma tacrolimus levels did not appear to be affected. No significant differences were shown in serum total, low-density lipoprotein, and high-density lipoprotein cholesterol levels aftertreatment. Nevertheless,triglyceride levels were significantly reduced (from 214.4 to 174.9 mg/dL; P = .0039). A decrease in body weight was also observed. Finally, patients treated with dipeptidyl peptidase V inhibitors achieved better glycosylated hemoglobin A1c levels than those treated with insulin.

CONCLUSIONS

Dipeptidyl peptidase IV inhibitors appear to be a safe, effective, and hypoglycemia-free option fortreatment of new onset diabetes in renaltransplant recipients and possibly provide better diabetes control than insulin therapy.

Genetic factors in pathogenesis of diabetes mellitus after kidney transplantation

Posttransplant diabetes mellitus (PTDM) is one of the major metabolic complications after transplantation of solid organs including the kidney. This type of diabetes mellitus affects allograft survival, cardiovascular complications and overall patient survival. The modifiable risk factors that contribute to PTDM include obesity, some viral infections (eg, hepatitis C virus, cytomegalovirus) and especially immunosuppressive drugs including corticosteroids, tacrolimus, cyclosporine and sirolimus. Currently, predisposing genetic factors have been considered important in PTDM development. The commonly evaluated genetic determinants include genes encoding transcription factors, cytokines, chemokines, adipokines, ionic channels, glucose transporters, cytochrome P450 enzymes and other enzymes metabolizing drugs, drug transporters. Unfortunately, the results of studies are inconclusive and differ between populations. There is a need for large genome-wide association study to identify the genetic risk factors associated with PTDM development.

Effects of Dipeptidyl Peptidase-4 Inhibitors on Hyperglycemia and Blood Cyclosporine Levels in Renal Transplant Patients with Diabetes: A Pilot Study

BACKGROUND

The use of dipeptidyl peptidase-4 (DPP-4) inhibitors is increasing among renal transplant patients with diabetes. However, the glucose-lowering efficacies of various DPP-4 inhibitors and their effects on blood cyclosporine levels have not been fully investigated. We compared the glucose-lowering efficacies of DPP 4 inhibitors and evaluate their effects on the blood levels of cyclosporine in renal transplant recipients with diabetes.

METHODS

Sixty-five renal allograft recipients who received treatment with DPP-4 inhibitors (vildagliptin, sitagliptin, or linagliptin) following kidney transplant were enrolled. The glucose-lowering efficacies of the DPP-4 inhibitors were compared according to the changes in the hemoglobin A1c (HbA1c) levels after 3 months of treatment. Changes in the trough levels of the cyclosporine were also assessed 2 months after treatment with each DPP-4 inhibitor.

RESULTS

HbA1c significantly decreased in the linagliptin group in comparison with other DPP-4 inhibitors (vildagliptin -0.38%±1.03%, sitagliptin -0.53%±0.95%, and linagliptin -1.40±1.34; P=0.016). Cyclosporine trough levels were significantly increased in the sitagliptin group compared with vildagliptin group (30.62±81.70 ng/mL vs. -24.22±53.54 ng/mL, P=0.036). Cyclosporine trough levels were minimally changed in patients with linagliptin.

CONCLUSION

Linagliptin demonstrates superior glucose-lowering efficacy and minimal effect on cyclosporine trough levels in comparison with other DPP-4 inhibitors in kidney transplant patients with diabetes.

Histamine inhibits adhesion molecule expression in human monocytes, induced by advanced glycation end products, during the mixed lymphocyte reaction

BACKGROUND AND PURPOSE

Post-transplant diabetes mellitus is a frequent complication among transplant recipients. Ligation of advanced glycation end products (AGEs) with their receptor on monocytes/macrophages plays important roles in the genesis of diabetic complications. The enhancement of adhesion molecule expression on monocytes/macrophages activates T-cells, reducing allograft survival. Out of four distinct AGE subtypes (AGE-2, AGE-3, AGE-4 and AGE-5), only AGE-2 and AGE-3 induced expression of intercellular adhesion molecules (ICAMs), output of cytokines and proliferation of lymphocytes, during the mixed lymphocyte reaction (MLR). Here we have assessed the role of histamine in the actions of AGEs during the MLR.

EXPERIMENTAL APPROACH

Human peripheral blood cells were used in these experiments. Flow cytometry was used to examine the expression of the ICAM-1, B7.1, B7.2 and CD40. Production of the cytokine interferon-gamma, and levels of cAMP were determined by elisa. Lymphocyte proliferation was determined by [(3)H]-thymidine uptake.

KEY RESULTS

Histamine concentration dependently inhibited the action of AGE-2 and AGE-3. The actions of histamine were antagonized by an H(2)-receptor antagonist, famotidine, and mimicked by H(2)/H(4)-receptor agonists, dimaprit and 4-methylhistamine. The effects of histamine were reversed by a protein kinase A (PKA) inhibitor, H89, and mimicked by dibutyryl cAMP and an adenylate cyclase activator, forskolin.

CONCLUSIONS AND IMPLICATIONS

Histamine down-regulated AGE-2- and AGE-3-induced expression of adhesion molecules, cytokine production and lymphocyte proliferation via histamine H(2) receptors and the cAMP/PKA pathway.

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

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

Association of hyperglycemia on allograft function in the early period after renal transplantation

Hyperglycemia is common following renal transplantation. This study was conducted to evaluate the relationship of perioperative serum glucose levels and acute rejection in 100 nondiabetic patients who underwent renal transplantation. Blood glucose was measured immediately following surgery and every 6 hours during the first 48 hours posttransplant as well as for 1 month to evaluate occurrence of acute rejection episodes (ARE). The rate of ARE was 33%. The mean blood glucose level immediately after surgery in patients with versus without ARE was 249.67 +/- 61.78 and 184.82 +/- 73.35 mg/dL, respectively (P=.000). There was no significant correlation between ARE and donor or recipient age or sex, delayed graft function, type of donor, or treatment. This study suggested a correlation between immediate blood glucose and ARE. In this regard, blood glucose monitoring and control during operation and immediate postoperatively may reduce the acute rejection rate.

Effects of a medication assistance program with medication therapy management on the health of renal transplant recipients

PURPOSE

The effects of a medication assistance program with medication therapy management (MTM) on the clinical outcomes and health-related quality of life (HQOL) of renal transplant recipients were studied.

METHODS

All renal transplant recipients who were enrolled in the Medication Access Program at the Medical College of Georgia for at least one year were included in the study. Patients' demographics, number of graft rejections (for one year pre-enrollment and one year post-enrollment), and diagnoses of hypertension, diabetes, and dyslipidemia were recorded and confirmed by medical and pharmacy records. The use of antihypertensive, antidiabetic, antilipemic, and immunosuppressant agents and laboratory values for fasting blood glucose, glycosylated hemoglobin (HbA(1c)), blood pressure, low-density-lipoprotein (LDL) cholesterol, total cholesterol, triglycerides, and serum immunosuppressant concentrations were identified for one year pre-enrollment and one year post-enrollment. HQOL was measured at the time of enrollment and one year post-enrollment.

RESULTS

Thirty-six adult renal transplant recipients were included in the study. All patients had hypertension, 72% had dyslipidemia, and 42% had diabetes. Patients received significantly more antihypertensive agents post-enrollment versus pre-enrollment (p < 0.001) and significantly more antidiabetic agents (p = 0.004) and antilipemics (p = 0.001). Measures of fasting blood glucose, glycosylated hemoglobin, LDL cholesterol, total cholesterol, triglycerides, blood pressure, and number of graft rejections decreased from pre-enrollment levels (p < 0.01). A significantly greater number of patients reached target serum cyclosporine levels post-enrollment versus pre-enrollment (p = 0.008). HQOL was significantly increased one year post-enrollment (p < 0.01).

CONCLUSION

A medication assistance program that included MTM services improved medication access, clinical outcomes, and HQOL in renal transplant recipients.

Management of Diabetes Mellitus in Hospitalized Patients: Efficiency and Effectiveness of Sliding-Scale Insulin Therapy

STUDY OBJECTIVE

To determine the efficiency and effectiveness of current prescribing practices relative to short- and intermediate-acting insulins in the prevention or treatment of acute hyperglycemic episodes in hospitalized patients with diabetes mellitus or hyperglycemia, and to identify clinical findings that influence the effectiveness of insulin therapy in these patients.

DESIGN

Retrospective observational study.

SETTING

University-affiliated hospital.

PATIENTS

Ninety consecutive adult inpatients who had orders placed for as-needed subcutaneous regular or lispro sliding-scale insulin.

MEASUREMENTS AND MAIN RESULTS

Medical records were reviewed for patients' clinical characteristics and responses to administered insulin that were recorded during each of the first 5 days of hospitalization in which sliding-scale insulin therapy was used. Despite the immediate or bedside availability of both computerized and manual means to record finger-stick blood glucose levels and insulin injections, uncertainties or missing information related to execution, timing, blood glucose levels, or insulin dose were present in approximately 30% of all anticipated points of care involving insulin. Ten episodes of hypoglycemia in six patients were associated with sliding-scale insulin. Appropriately timed, successive glucose measurements documented a decrement in elevated blood glucose values to within the target range of 90-130 mg/dl after 76 (12%) of 621 sliding-scale insulin injections. Glucose levels remained elevated, and insulin effects were therefore subtherapeutic after 523 injections (84%). Despite blood glucose levels that remained persistently elevated, corresponding adjustments in either the timing or the dose of insulin were made infrequently. Sliding-scale insulin regimens were never adjusted in 73 patients (81%). Through 5 days of therapy, the proportion of patients who attained good glycemic control ranged from 2-10% (mean 6%). The mode of overall glycemic control was poor, with 51-68% of patients in this category on any given day. Overall, treated diabetic and hyperglycemic patients were more likely to be poorly controlled than relatively well controlled.

CONCLUSION

Our findings reveal outcomes associated with sliding-scale insulin that are widely variable, often ineffectual, and prone to deficiencies in monitoring, documentation, and prescribing soundness. Efforts to improve glycemic control in hospitalized patients are clearly needed.

Posttransplant Diabetes Mellitus: Impact of Good Blood Glucose Regulation on Renal Transplant Recipient Outcome

Posttransplant diabetes mellitus (PTDM) is a frequent complication among renal transplant recipients. This study sought to compare clinical outcomes of patients with PTDM who had strict glucose control with nondiabetic patients and to identify risk factors for atherosclerotic disease in both groups. We retrospectively examined 204 renal allograft recipients transplanted at our center between 1996 and 2002. Demographic features, dialysis and posttransplantation duration, smoking, body mass index, medications, comorbid diseases, number of HLA mismatches, and laboratory parameters including serum levels of creatinine, albumin, calcium, phosphorus, C-reactive protein, lipid parameters, and parathyroid hormone were analyzed as possible risk factors for atherosclerotic disease. Patients were followed for a mean of 59.7 +/- 23.6 months. PTDM was diagnosed according to the American Diabetic Association criteria or the need for an insulin/oral hypoglycemic agent. Twenty-six patients developed PTDM, and these patients had very good diabetes control. One patient with poorly regulated PTDM was excluded. Adverse events which were documented in 24 patients were more frequent among patients with PTDM. Mean age was found to be an independent risk factor for atherosclerotic disease, whereas PTDM was not. There were no differences regarding other atherosclerosis-related or other risk factors (including serum C-reactive protein levels and lipid profiles) between the groups. Nondiabetic subjects tended to have longer graft survival than patients with PTDM, but this finding was not statistically significant. PTDM is an important risk factor for developing atherosclerotic disease. Good control of blood glucose levels can decrease the high morbidity rates and negative influence of PTDM on patient and graft survival rates in this population.

De novo diabetic nephropathy on renal allografts

BACKGROUND

Posttransplant diabetes mellitus (PTDM) is a well-recognized clinical problem following renal transplantation. Long-term risks of PTDM are similar to those of diabetes mellitus in general population. The aim of our study was to identify de novo diabetic nephropathy (DN) in our group of patients with PTDM.

METHODS

Thirty-four patients with PTDM were reviewed retrospectively. Light microscopy, immunofluorescence, and electron microscopy techniques were performed in 10 of 21 patients with graft biopsy.

RESULTS

Five patients (four women, one man), aged 47.4 years (range, 29 to 58), four of whom received cadaveric grafts, were found to have de novo DN. Their serum creatinine was 211.4 micromol/L (range, 140 to 294). Three patients were slightly proteinuric (0.3 to 0.5 g/L). PTDM was diagnosed 2.4 months after transplantation (range, 1 to 6). Histologic diagnosis of de novo DN was made, on average, 52.6 months after transplantation (range, 8 to 115), and 50.2 months (range, 2 to 114) after PTDM. De novo DN presented as diffuse diabetic glomerulosclerosis in four patients and nodular diabetic sclerosis in one patient, and combined with transplant glomerulopathy in all five patients. The mean graft survival time for this group of patients was equivalent with a control group. Although the difference in slopes of serum creatinine between the studied groups was clinically relevant, it was not statistically significant.

CONCLUSION

In view of our findings, when histologic de novo DN was found in 5 out of 10 patients, one could conclude that de novo DN could be a frequent complication of PTDM.