New onset dyslipidemia after renal transplantation: is there a difference between tacrolimus and cyclosporine?

Managing dyslipidemia in solid organ transplant patients

Solid organ transplant recipients face an increased risk of dyslipidemia, which contributes to cardiovascular complications. Commonly used drugs such as ciclosporin and tacrolimus can aggravate and cause dyslipidemia. Immunosuppressive drugs particularly ciclosporin and tacrolimus are also known to worsen dyslipidemia in transplant recipients. Mammalian target of rapamycin (mTOR) inhibitors like sirolimus and everolimus also alter lipid metabolism. Lifestyle and dietary modifications should be encouraged. Careful consideration of immunosuppressant choices is also vital to control dyslipidemia. Statins are recommended as first-line agents for lipid-lowering therapy, with consideration for potential drug interactions. Other options, such as ezetimibe and nicotinic acid, may be considered as alternatives. The management of dyslipidemia in renal transplant patients mainly involves statin therapy, although the clinical effectiveness in this population is not well-documented. Lifestyle modifications, careful drug selection, and statin therapy are key components in managing dyslipidemia in solid organ transplant patients.

Statins in Kidney Transplant Recipients: Usage, All-Cause Mortality, and Interactions with Maintenance Immunosuppressive Agents

SIGNIFICANCE STATEMENT

Cardiovascular diseases account for 32% of deaths among kidney transplant recipients. Statin therapy is common in this population. However, its effect on mortality prevention remains unclear among kidney transplant recipients, whose clinical risk profile might be unique because of concomitant immunosuppressive therapy. In this national study of 58,264 single-kidney transplant recipients, statin use was associated with a 5% decrease in mortality. More importantly, this protective association was stronger among those who used a mammalian target of rapamycin (mTOR) inhibitor for immunosuppression (27% decrease in mTOR inhibitor users versus 5% in nonusers). Our results suggest that statin therapy may reduce mortality in kidney transplant recipients and that the strength of this protective association may vary by immunosuppression regimen.

BACKGROUND

Cardiovascular diseases are the leading cause of mortality in kidney transplant (KT) recipients, accounting for 32% of deaths. Statins are widely used in KT recipients, but effectiveness for preventing mortality remains unclear in this population, especially because of interaction between statins and immunosuppressive agents. We analyzed a national cohort to assess the real-world effectiveness of statins for reducing all-cause mortality in KT recipients.

METHODS

We studied statin use and mortality among 58,264 adults (18 years or older) who received single kidneys between 2006 and 2016 and had Medicare part A/B/D. Statin use was ascertained from Medicare prescription drug claims and deaths from Center for Medicare and Medicaid Services records. We estimated the association of statin use with mortality using multivariable Cox models, with statin use as a time-varying exposure and immunosuppression regimen as effect modifiers.

RESULTS

Statin use increased from 45.5% at KT to 58.2% at 1-year post-KT to 70.9% at 5-year post-KT. We observed 9785 deaths over 236,944 person-years. Overall, statin use was significantly associated with lower mortality (adjusted hazard ratio [aHR], 0.95; 95% confidence interval [CI], 0.90 to 0.99). The strength of this protective association varied by calcineurin inhibitor use (among tacrolimus users, aHR, 0.97; 95% CI, 0.92 to 1.03 versus among calcineurin nonusers, aHR, 0.72; 95% CI, 0.60 to 0.87; interaction P =0.002), mammalian target of rapamycin (mTOR) inhibitor use (among mTOR inhibitor users, aHR, 0.73; 95% CI, 0.57 to 0.92 versus among nonusers, aHR, 0.95; 95% CI, 0.91 to 1.00; interaction P =0.03), and mycophenolate use (among mycophenolate users, aHR, 0.96; 95% CI, 0.91 to 1.02 versus among nonusers, aHR, 0.76; 95% CI, 0.64 to 0.89; interaction P =0.002).

CONCLUSION

Real-world evidence supports statin therapy for reducing all-cause mortality in KT recipients. Effectiveness might be greater when combined with mTOR inhibitor-based immunosuppression.

Cardiovascular effects of immunosuppression agents

Immunosuppressive medications are widely used to treat patients with neoplasms, autoimmune conditions and solid organ transplants. Key drug classes, namely calcineurin inhibitors, mammalian target of rapamycin (mTOR) inhibitors, and purine synthesis inhibitors, have direct effects on the structure and function of the heart and vascular system. In the heart, immunosuppressive agents modulate cardiac hypertrophy, mitochondrial function, and arrhythmia risk, while in vasculature, they influence vessel remodeling, circulating lipids, and blood pressure. The aim of this review is to present the preclinical and clinical literature examining the cardiovascular effects of immunosuppressive agents, with a specific focus on cyclosporine, tacrolimus, sirolimus, everolimus, mycophenolate, and azathioprine.

Surgical Management of Lower Extremity Wounds in the Solid Organ Transplant Patient Population: Surgeon Beware

Objective: To evaluate our institutional outcomes of surgical management of lower extremity (LE) wounds in the solid organ transplant recipient population. Approach: An 8-year retrospective review was conducted for all solid organ transplantation (SOT) recipients with LE wounds necessitating surgical management at our tertiary limb salvage center. Outcomes of interest included wound healing, surgical treatment, progression to amputation, and amputation level. Factors contributing to amputation progression were analyzed. The article adheres to the Strengthening the Reporting of Observational Studies in Epidemiology statement. Results: Sixty-four SOT recipients underwent surgical management for their LE wounds between 2010 and 2018. Median number of surgeries per patient was 5 (interquartile range = 2-8); 47 of 64 patients (73.4%) underwent amputation, and 17 of 64 patients (26.6%) underwent nonamputation surgical management. In the amputation group, the majority of primary amputations were minor (42/47, 89.4%); 24 of 42 (57.1%) patients progressed to a higher amputation level, 16 of 42 (38.1%) healed after their index procedure, and 2 of 42 (4.8%) were lost to follow-up (LTFU) after their primary minor amputation. Five of 47 (10.6%) patients undergoing amputations required primary below-knee amputations. In the nonamputation group, 15 of 17 (88.2%) healed, 1 of 17 (5.9%) expired, and 1 of 17 (5.9%) was LTFU. Innovation: To identify the outcomes of patients undergoing surgical management for LE wounds after SOT and elucidate clinical factors that impact the rate of limb salvage. Conclusions: This is the first comprehensive analysis of LE wounds in the transplant population. Our analysis indicates high rates of failed minor amputation, and frequent progression to major amputation in SOT patients. Preexisting comorbidities and immunosuppressive regimens complicate limb salvage; therefore, further research is warranted to optimize surgical LE wound management in this population.

Non-HDL cholesterol is an independent predictor of long-term cardiovascular events in patients with dyslipidemia after renal transplantation

BACKGROUND

Posttransplant dyslipidemia is a common condition in renal transplantation recipients (RTR) and is related to poor cardiac outcomes. We aimed to demonstrate the value of non-high-density lipoprotein cholesterol (non-HDL-C) in predicting long-term major cardiovascular and cerebrovascular events (MACCE) in RTR with dyslipidemia.

METHODS

Patients who had undergone renal transplantation between 2011 and 2019 were retrospectively analysed and were classified as normal non-HDL-C and high non-HDL-C groups based on first year levels. Development of high non-HDL-C levels was used to predict the occurrence of MACCE (a combination of cardiac death, nonfatal myocardial infarction, unstable angina, and nonfatal stroke) and all-cause death during the long-term follow-up.

RESULTS

Overall, 674 patients were included, of whom 470 (69.7%) were male; the mean age was 43.6 ± 13.2 years. The mean follow-up duration was 5.5 ± 2.29 years 1 year after the transplant. MACCE occurred during the follow-up in 102 (61.8%) patients in the high non-HDL-C group and 13 (2.6%) patients in the normal non-HDL-C group (P < .001). High non-HDL-C was a predictor of MACCE in the multivariate analysis (hazard ratio [HR] 1.02, 95% confidence interval [CI] 1.01-1.02, P < .001). Smoking (HR: 1.92, 95% CI 1.16-3.20, P < .001), cadaver graft (HR: 2.55, 95% CI 1.52-4.26, P < .001), and left ventricular ejection fraction (HR: 0.96, 95% CI 0.94-0.98, P < .001) were also predictors of MACCE. Kaplan-Meier analysis revealed that all MACCE components and all-cause mortality were significantly higher in the high non-HDL-C group (P < .001).

CONCLUSION

Non-HDL-C was closely related to long-term cardiac outcomes in RTR with dyslipidemia. Non-HDL-C should be among the primary goals in lipid-lowering treatment in post-transplant dyslipidemia.

Delayed diagnosis and treatment of extreme hypertriglyceridemia due to rejection of a lipemic sample

Introduction

Most laboratories routinely determine haemolysis, icterus and lipemia indices to identify lipemic samples and reject potentially affected results. Hypertriglyceridemia is the most common cause of lipemia and severe hypertriglyceridemia (≥ 11.3 mmol/L) is a major risk factor of acute pancreatitis.

Laboratory analysis

A 56-year-old woman attended the outpatient clinic for a follow-up visit 1 month after a kidney transplantation. Her immunosuppressive therapy consisted of corticosteroids, cyclosporine, and mycophenolic acid. The routine clinical chemistry sample was rejected due to extreme lipemia. The comment "extreme lipemic sample" was added on the report, but the requesting physician could not be reached. The Cobas 8000 gave a technical error (absorption > 3.3) for the HIL-indices (L-index: 38.6 mmol/L) which persisted after high-speed centrifugation. The patient was given a new appointment 2 days later. The new sample was also grossly lipemic and gave the same technical error (L-index: 35.9 mmol/L).

What happened

The second sample was manually diluted 20-fold after centrifugation to obtain a result for triglycerides within the measuring range (0.10-50.0 mmol/L). Triglycerides were 169.1 mmol/L, corresponding to very severe hypertriglyceridemia. This result was communicated to the nephrologist and the patient immediately recalled to the hospital. She received therapeutic plasma exchange the next day and did not develop acute pancreatitis.

Main lesson

This case illustrates the delicate balance between avoiding the release of unreliable results due to lipemia and the risk of delayed diagnosis when results are rejected. Providing an estimate of the degree of hypertriglyceridemia might be preferable to rejecting the result.

Cardiovascular and metabolic disease in the liver transplant recipient

Liver transplantation has led to great improvements in long-term survival in patients with decompensated liver disease and hepatocellular carcinoma. Cardiovascular disease is the leading cause of non-graft-related deaths and has increased prevalence in liver allograft recipients. This is partly secondary to higher post-transplant rates of metabolic risk factors-notably obesity, hypertension, dyslipidemia, and diabetes mellitus, which comprise metabolic syndrome. Post-transplantation metabolic syndrome is expected to be a growing factor in morbidity and mortality as transplant candidates trend older, the rates of metabolic risk factors in the general population increase, non-alcoholic steatohepatitis grows disproportionally as an indication for transplantation, and post-transplantation survival lengthens. This review discusses the incidence and contributory factors for post-transplant increases in metabolic disease, as well as the burden of cardiovascular disease in the liver allograft recipient. Patients with pre-transplant diabetes or obesity are at particularly high risk for post-transplant metabolic syndrome, and would likely benefit from closer surveillance and more aggressive medical management of risk factors. In metabolic disease resistant to initial medical therapies, tailoring of immunosuppressive regimens may further assist in minimizing long-term cardiovascular disease, although this must be done with caution to avoid worsening the risk of graft failure.

Statin therapy for preventing cardiovascular diseases in patients treated with tacrolimus after kidney transplantation

Background

Lipid abnormalities are prevalent in tacrolimus-treated patients. The aim of the study was to evaluate the preventive effects of statin therapy on major adverse cardiovascular events (MACE) in patients treated with tacrolimus-based immunosuppression after kidney transplantation (KT), and to identify the risk factors.

Methods

This observational cohort study included adult patients who underwent KT and were treated with tacrolimus. Patients who received any lipid-lowering agents except statins, or had a history of immunosuppressant use before transplantation were excluded. The primary outcome was the adjusted risk of the first occurrence of MACE. The secondary outcomes included the risk of individual cardiovascular disease (CVD) and changes in cholesterol level. Subgroup analyses were performed in the statin-user group according to the dosage and/or type of statin.

Results

Compared with the control group (n=73), the statin-users (n=92) had a significantly reduced risk of MACE (adjusted HR, 0.31; 95% CI, 0.13–0.74). In the Cox regression analysis, old age, history of CVD, and comorbid hypertension were identified as independent factors associated with increased MACE. The total cholesterol levels were not significantly different between the two groups. Subjects with higher cumulative defined daily dose of statins had significantly lower risks of MACE.

Conclusion

Statin therapy in patients treated with tacrolimus after KT significantly lowered the risk of MACE. Long-term statin therapy is clearly indicated in older kidney transplant recipients for secondary prevention.

Vascular calcification, bone and mineral metabolism after kidney transplantation

The development of end stage renal failure can be seen as a catastrophic health event and patients with this condition are considered at the highest risk of cardiovascular disease among any other patient groups and risk categories. Although kidney transplantation was hailed as an optimal solution to such devastating disease, many issues related to immune-suppressive drugs soon emerged and it became evident that cardiovascular disease would remain a vexing problem. Progression of chronic kidney disease is accompanied by profound alterations of mineral and bone metabolism that are believed to have an impact on the cardiovascular health of patients with advanced degrees of renal failure. Cardiovascular risk factors remain highly prevalent after kidney transplantation, some immune-suppression drugs worsen the risk profile of graft recipients and the alterations of mineral and bone metabolism seen in end stage renal failure are not completely resolved. Whether this complex situation promotes progression of vascular calcification, a hall-mark of advanced chronic kidney disease, and whether vascular calcifications contribute to the poor cardiovascular outcome of post-transplant patients is reviewed in this article.

Correlation between CD14+CD16++ monocytes in peripheral blood and hypertriglyceridemia after allograft renal transplantation

BACKGROUND

Cardio-cerebrovascular diseases are key factors causing recipient the death after kidney transplantation (KT). Hypertriglyceridemia (HTG), a complication commonly occurring among KT patients, is a major risk factor for cardio-cerebrovascular diseases. The objective of this study was to examine the correlation between peripheral CD14+CD16++ monocytes in KT patients and blood lipids as well as factors affecting hyperglycemia, seeking to understand mechanisms of inflammatory immune reactions.

METHODS

KT patients (n = 60) were divided into subjects with HTG (n = 35) versus without HTG (n = 25). A cohort of healthy participants (55 cases) was divided into the cases without (n = 30) versus with HTG (n = 25). The proportion of peripheral CD14+CD16 ++ monocytes was determined using flow cytometry and hematology, and biochemical indicators were measured by conventional methods. We correlated HTG with these indicators.

RESULTS

The proportion of peripheral blood CD14+CD16++ monocytes among the renal transplant group was significantly lower (P < .05) than that of normal controls. The expression of CD14+CD16++ monocytes among transplant recipients positively correlated with triglycerides (R = 0.449 and R = 0.008, respectively).

CONCLUSION

CD14+CD16++ mononcytes in peripheral blood may represent an independent risk factor for HTG after KT.

Belatacept-based regimens are associated with improved cardiovascular and metabolic risk factors compared with cyclosporine in kidney transplant recipients (BENEFIT and BENEFIT-EXT studies)

BACKGROUND

Cardiovascular disease, the most common cause of death with a functioning graft among kidney transplant recipients, can be exacerbated by immunosuppressive drugs, particularly the calcineurin inhibitors. Belatacept, a selective co-stimulation blocker, may provide a better cardiovascular/metabolic risk profile than current immunosuppressants.

METHODS

Cardiovascular and metabolic endpoints from two Phase III studies (BENEFIT and BENEFIT-EXT) of belatacept-based regimens in kidney transplant recipients were assessed at month 12. Each study assessed belatacept in more intensive (MI) and less intensive (LI) regimens versus cyclosporine A (CsA). These secondary endpoints included changes in blood pressure, changes in serum lipids, and the incidence of new-onset diabetes after transplant (NODAT).

RESULTS

A total of 1209 patients were randomized and transplanted across the two studies. Mean systolic blood pressure was 6 to 9 mm Hg lower and mean diastolic blood pressure was 3 to 4 mm Hg lower in the MI and LI groups versus CsA (P ≤ 0.002) across both studies at month 12. Non-HDL cholesterol was lower in the belatacept groups versus CsA (P<0.01 MI or LI vs. CsA in each study). Serum triglycerides were lower in the belatacept groups versus CsA (P<0.02 MI or LI vs. CsA in each study). NODAT occurred less often in the belatacept groups versus CsA in a prespecified pooled analysis (P<0.05 MI or LI vs. CsA).

CONCLUSIONS

At month 12, belatacept regimens were associated with better cardiovascular and metabolic risk profiles, with lower blood pressure and serum lipids and less NODAT versus CsA. The overall profile of belatacept will continue to be assessed over the 3-year trials.

HMG-CoA reductase inhibitors in kidney transplant recipients receiving tacrolimus: statins not associated with improved patient or graft survival

Background

The beneficial effects of early statin use in kidney transplant recipients, especially those on tacrolimus-based immunosuppression, are not well established. We evaluated the predictors of statin use following kidney transplantation and examined its association with patient and allograft survival.

Methods

We examined 615 consecutive patients who underwent kidney transplant at our institution between January 1998 and January 2002. Statin use was assessed at baseline and 3, 6, 9, and 12 months following kidney transplant. Patients were followed for allograft and patient survival.

Results

36% of the 615 kidney transplant recipients were treated with statin treatment. Statin use increased over the course of the study period. Older age, elevated body mass index, higher triglyceride levels, hypercholesterolemia, diabetes, history of myocardial infarction were associated with higher rates of statin use; elevated alkaline phosphatase levels and CMV IgG seropositivity were associated with less statin use. Older age, elevated BMI and hypercholesterolemia remained significant predictors of increased statin use after accounting for covariates using multiple regression. The early use of statins was not associated with improvements in unadjusted patient survival [HR 0.99; 95%CI 0.72-1.37] or graft survival [HR 0.97; 95% CI 0.76-1.24]. The risks of death and graft survival were not consistently reduced with exposure to statin using either adjusted models or propensity scores in Cox Proportional Hazards models.

Conclusions

In a kidney transplant population primarily receiving tacrolimus-based immunosuppression, early statin use was not associated with significantly improved graft or patient survival.

Dyslipidemia following kidney transplantation: diagnosis and treatment

Lipid abnormalities are a common complication of kidney transplantation, occurring in up to 60% of patients. In fact, impairment of lipid metabolism is often present before renal transplantation due to the uremic state. After transplantation and recovery of renal function, lipid disturbances usually persist but show a different profile due to the various effects of immunosuppressive drugs on lipid metabolism. Actually, steroids, calcineurin inhibitors, and mammalian target of rapamycin inhibitors usually lead to quantitative and qualitative abnormalities of very low-density, low-density, and high-density lipoproteins. As cardiovascular diseases remain the leading cause of death in renal transplant recipients, management of dyslipidemia and other traditional risk factors, such as smoking, arterial hypertension, diabetes mellitus, and obesity, is of great importance to prevent cardiovascular complications and chronic allograft dysfunction. This review addresses the causes of dyslipidemia, the role of immunosuppressive drugs, and current recommendations to manage lipid disorders in renal transplant recipients.