Effect of fluvastatin on endothelium-dependent brachial artery vasodilation in patients after renal transplantation

Management of blood lipids in post-kidney transplant patients: a systematic review and network meta-analysis

Introduction

The primary objective of this systematic review was to provide an overview of the efficacy and safety of various lipid-lowering therapies in patients post-kidney transplant (PKT), given the limited existing literature. Considering the restricted number of available studies, this work aimed to summarize the existing evidence regarding the effectiveness of different lipid-lowering treatments in PKT patients. The effects of various lipid-lowering therapeutic regimens on lipid levels were compared, and their safety was assessed, with the heterogeneity of treatment protocols acknowledged.

Material and Methods

Randomized controlled trials investigating different treatment regimens (DTRs) for regulating lipid levels in PKT patients were systematically retrieved from PubMed, Cochrane Library, and Embase, from inception to March 2024. Literature quality was assessed employing the Cochrane risk of bias assessment tool. Data analysis and graphical representation were performed employing RevMan5.3 and Stata 20.0. The surface under the cumulative ranking area (SUCRA) compared the effects of DTRs on lipid profiles, incidence of adverse events, and all-cause mortality in PKT patients.

Results

Fifteen studies were included, comprising 5,768 PKT patients and involving 9 treatment regimens. The results revealed that, for changes in high-density lipoprotein cholesterol (HDL-C), the SUCRA rankings from highest to lowest among PKT patients receiving DTRs were statins + ezetimibe (70%), placebo (61.5%), fibrates (57.2%), statins (44.1%), and fish oil (17.3%). Regarding changes in low-DL-C (LDL-C), the SUCRA rankings from highest to lowest among PKT patients receiving DTRs were statins (68.2%), statins + ezetimibe (67.5%), fish oil (53.4%), fibrates (34.5%), and placebo (26.5%). For the change in total cholesterol (TC) levels, a network meta-analysis (NMA) revealed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for TC change were statins + ezetimibe (97.6%), proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9 inhibitors) (74.3%), fish oil (64.3%), statins (61.6%), fibrates (47.2%), placebo (31.6%), calcineurin phosphatase inhibitors (11.9%), and immunosuppressants (11.4%). Regarding the change in triglyceride (TG) levels, a NMA showed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for TG change were fibrates (99.9%), statins (68.9%), PCSK9 inhibitors (66.6%), statins + ezetimibe (55.1%), placebo (49.2%), fish oil (45.0%), immunosuppressants (7.8%), and calcineurin phosphatase inhibitors (7.6%). For the occurrence of kidney transplant failure, a NMA revealed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for reducing the incidence of kidney transplant failure were PCSK9 inhibitors (69.0%), calcineurin phosphatase inhibitors (63.0%), statins (61.5%), placebo (55.1%), steroids (51.8%), immunosuppressants (27.1%), and fibrates (22.5%). Regarding all-cause mortality, a NMA showed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for reducing all-cause mortality were PCSK9 inhibitors (90.5%), statins (55.8%), and placebo (3.7%).

Conclusion

In reducing lipid levels in PKT patients, combination therapy with statins and ezetimibe demonstrated notable advantages and higher effectiveness. PCSK9 inhibitors exhibited greater advantages in reducing adverse events and mortality rates in PKT patients, with higher safety.

Statin Therapy and Flow-Mediated Dilation: A Systematic Review and Dose-Response Meta-Analysis Using the GRADE of Data from Randomized Controlled Trials

INTRODUCTION

A previous meta-analysis reported the positive effects of statin therapy on endothelial function. However, the obtained result had several limitations that necessitated updating the information in this field. Therefore, a systematic and meta-analysis review was conducted to determine whether statin therapy could improve endothelial function, as assessed by flow-- mediated dilation (FMD).

METHODS

MEDLINE, SciVerse Scopus, and Clarivate Analytics Web of Science were searched to identify randomized placebo-controlled trials assessing the impact of statin therapy on FMD. A random-effects model was used for meta-analysis to calculate the mean difference in weight. Meta- regression and subgroup analyses were used to identify sources of heterogeneity. In addition, nonlinear dose-response, quality of evidence, influence analysis, and publication bias evaluation were assessed using standard methods.

RESULT

Thirty-five trials (41 arms) involving 2178 participants were included in the meta-analysis study. Statin treatment significantly improved FMD [weighted mean difference (WMD): 1.7%, 95% CI: 1.3-2.2, p < 0.001). However, significant heterogeneity was observed (I2=97.9%, p < 0.001). The results of the subgroup analysis showed that health status can contribute to heterogeneity. Non-linear dose-response analysis revealed the most significant improvement in FMD with atorvastatin at a dose of 20 mg/day and simvastatin at 80 mg/day.

CONCLUSION

Statin therapy significantly improved endothelial function, as assessed by FMD. These changes are clinically significant, but their use should be approached with caution.

Effects of Statins on Lipid Profile of Kidney Transplant Recipients: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To assess the benefits of statins on lipid profile in kidney transplant recipients via a meta-analysis.

METHODS

We systematically identified peer-reviewed clinical trials, review articles, and treatment guidelines from PubMed, Embase, the Cochrane Library, Wanfang, Chinese National Knowledge Infrastructure (CNKI), SinoMed (CBM), and Chongqing VIP databases from inception to April 2019. In the analysis, only randomized controlled clinical trials performed in human were included.

RESULTS

Eight articles were included in the analysis, involving 335 kidney transplant recipients who received statins and 350 kidney transplant patients as the control group. Results revealed that statins improved the lipid profile of kidney transplant recipients. Specifically, statin therapy significantly reduced total cholesterol and low-density lipoprotein cholesterol. However, it had no effects on high-density lipoprotein cholesterol and triglyceride levels.

CONCLUSIONS

The present study provides valuable knowledge on the potential benefits of statins in kidney transplant recipients. This meta-analysis shows that statin therapy modifies the lipid profile in this patient population.

Fluvastatin Decreases Oxidative Stress in Kidney Transplant Patients

OBJECTIVE

Oxidative stress has been suggested to have a pivotal role in the development of cardiovascular disease in kidney transplant patients (KTPs). The effects of fluvastatin on oxidative status in KTPs have not been well evaluated. The aim of the present study was to evaluate the effects of fluvastatin on oxidative status by investigating erythrocyte superoxide dismutase (SOD), erythrocyte glutathione peroxidase (GPx), serum paraoxonase (PON1), and serum arylesterase (ARE), along with lipid peroxidation products, serum malonldialdehyde, and apolipoprotein B malondialdehyde (ApoB MDA).

METHODS

Eighteen KTPs were included in the present study. Blood samples were obtained after 1 night's fast. Erythrocyte SOD, erythrocyte GPx, serum PON1, serum ARE, serum MDA, and ApoB MDA were measured using methods described previously. Paired-sample t test was used for comparing the changes from week 0 to week 4 of parameters that might be associated with fluvastatin treatment.

RESULTS

The present study has shown that erythrocyte SOD and GPx, and serum PON1 and ARE activities increased at the fourth week of the statin treatment. Furthermore an increase in the antioxidant enzymes following fluvastatin may be a clue for the antioxidant effects of this drug. Four weeks of fluvastatin long-acting tablets 80 mg/day led to a decrease in plasma Apo-MDA and MDA levels.

CONCLUSION

The findings of the present study demonstrate that fluvastatin 80 mg long-acting tablets may be used safely for 4 weeks and decrease atherogenic lipoproteins in KTPs. Furthermore, after 4 weeks of fluvastatin treatment, the levels of antioxidant parameters increased and oxidative parameters decreased. Further placebo-controlled treatment studies would be helpful to evaluate the effects of fluvastatin on oxidant and antioxidant parameters including PON1 in patients with KT.

HMG CoA reductase inhibitors (statins) for kidney transplant recipients

BACKGROUND

People with chronic kidney disease (CKD) have higher risks of cardiovascular disease compared to the general population. Specifically, cardiovascular deaths account most deaths in kidney transplant recipients. Statins are a potentially beneficial intervention for kidney transplant patients given their established benefits in patients at risk of cardiovascular disease in the general population. This is an update of a review first published in 2009.

OBJECTIVES

We aimed to evaluate the benefits (reductions in all-cause and cardiovascular mortality, major cardiovascular events, myocardial infarction and stroke, and progression of CKD to requiring dialysis) and harms (muscle or liver dysfunction, withdrawal, cancer) of statins compared to placebo, no treatment, standard care, or another statin in adults with CKD who have a functioning kidney transplant.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 29 February 2012 through contact with the Trials Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs that compared the effects of statins with placebo, no treatment, standard care, or statins on mortality, cardiovascular events, kidney function and toxicity in kidney transplant recipients.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed risk of bias. Treatment effects were expressed as mean difference (MD) for continuous outcomes (lipids, glomerular filtration rate (GFR), proteinuria) and relative risk (RR) for dichotomous outcomes (major cardiovascular events, mortality, fatal or non-fatal myocardial infarction, fatal or non-fatal stroke, elevated muscle or liver enzymes, withdrawal due to adverse events, cancer, end-stage kidney disease (ESKD), acute allograft rejection) together with 95% confidence intervals (CI).

MAIN RESULTS

We identified 22 studies (3465 participants); 17 studies (3282 participants) compared statin with placebo or no treatment, and five studies (183 participants) compared two different statin regimens.From data generally derived from a single high-quality study, it was found that statins may reduce major cardiovascular events (1 study, 2102 participants: RR 0.84, CI 0.66 to 1.06), cardiovascular mortality (4 studies, 2322 participants: RR 0.68, CI 0.45 to 1.01), and fatal or non-fatal myocardial infarction (1 study, 2102 participants: RR 0.70, CI 0.48 to 1.01); although effect estimates lack precision and include the possibility of no effect.Statins had uncertain effects on all-cause mortality (6 studies, 2760 participants: RR 1.08, CI 0.63 to 1.83); fatal or non-fatal stroke (1 study, 2102 participants: RR 1.18, CI 0.85 to 1.63); creatine kinase elevation (3 studies, 2233 participants: RR 0.86, CI 0.39 to 1.89); liver enzyme elevation (4 studies, 608 participants: RR 0.62, CI 0.33 to 1.19); withdrawal due to adverse events (9 studies, 2810 participants: RR 0.89, CI 0.74 to 1.06); and cancer (1 study, 2094 participants: RR 0.94, CI 0.82 to 1.07).Statins significantly reduced serum total cholesterol (12 studies, 3070 participants: MD -42.43 mg/dL, CI -51.22 to -33.65); low-density lipoprotein cholesterol (11 studies, 3004 participants: MD -43.19 mg/dL, CI -52.59 to -33.78); serum triglycerides (11 studies, 3012 participants: MD -27.28 mg/dL, CI -34.29 to -20.27); and lowered high-density lipoprotein cholesterol (11 studies, 3005 participants: MD -5.69 mg/dL, CI -10.35 to -1.03).Statins had uncertain effects on kidney function: ESKD (6 studies, 2740 participants: RR 1.14, CI 0.94 to 1.37); proteinuria (2 studies, 136 participants: MD -0.04 g/24 h, CI -0.17 to 0.25); acute allograft rejection (4 studies, 582 participants: RR 0.88, CI 0.61 to 1.28); and GFR (1 study, 62 participants: MD -1.00 mL/min, CI -9.96 to 7.96).Due to heterogeneity in comparisons, data directly comparing differing statin regimens could not be meta-analysed. Evidence for statins in people who have had a kidney transplant were sparse and lower quality due to imprecise effect estimates and provided limited systematic evaluation of treatment harm.

AUTHORS' CONCLUSIONS

Statins may reduce cardiovascular events in kidney transplant recipients, although treatment effects are imprecise. Statin treatment has uncertain effects on overall mortality, stroke, kidney function, and toxicity outcomes in kidney transplant recipients. Additional studies would improve our confidence in the treatment benefits and harms of statins on cardiovascular events in this clinical setting.

Benefits and harms of statin therapy for persons with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Statins have uncertain benefits in persons with chronic kidney disease (CKD) because individual trials may have insufficient power to determine whether treatment effects differ with severity of CKD.

PURPOSE

To summarize the benefits and harms of statin therapy for adults with CKD and examine whether effects of statins vary by stage of kidney disease.

DATA SOURCES

Cochrane and EMBASE databases (inception to February 2012).

STUDY SELECTION

Randomized trials comparing the effects of statins with placebo, no treatment, or another statin on mortality and cardiovascular outcomes.

DATA EXTRACTION

Two independent reviewers extracted data and assessed risk of bias.

DATA SYNTHESIS

Eighty trials comprising 51099 participants compared statin with placebo or no treatment. Treatment effects varied with stage of CKD. Moderate- to high-quality evidence indicated that statins reduced all-cause mortality (relative risk [RR], 0.81 [95% CI, 0.74 to 0.88]), cardiovascular mortality (RR, 0.78 [CI, 0.68 to 0.89]), and cardiovascular events (RR, 0.76 [CI, 0.73 to 0.80]) in persons not receiving dialysis. Moderate- to high-quality evidence indicated that statins had little or no effect on all-cause mortality (RR, 0.96 [CI, 0.88 to 1.04]), cardiovascular mortality (RR, 0.94 [CI, 0.82 to 1.07]), or cardiovascular events (RR, 0.95 [CI, 0.87 to 1.03]) in persons receiving dialysis. Effects of statins in kidney transplant recipients were uncertain. Statins had little or no effect on cancer, myalgia, liver function, or withdrawal from treatment, although adverse events were evaluated systematically in fewer than half of the trials.

LIMITATION

There was a reliance on post hoc subgroup data for earlier stages of CKD.

CONCLUSION

Statins decrease mortality and cardiovascular events in persons with early stages of CKD, have little or no effect in persons receiving dialysis, and have uncertain effects in kidney transplant recipients.

Influence of erythropoietin on arterial stiffness and endothelial function in renal transplant recipients

BACKGROUND/AIMS

Recent retrospective studies suggest an association of therapy with erythropoiesis-stimulating agents (ESAs) and increased mortality in renal transplant recipients (RTR). Large artery structure and function are significantly impaired in RTR which contributes to their high cardiovascular morbidity and could be altered by erythropoietin. We aimed to examine the influence of ESA therapy on large artery stiffness and endothelial function in RTR.

METHODS

63 RTR with chronic allograft dysfunction and renal anemia were randomized to a group receiving darbepoetin alfa (Dar) and a control group (Co). At baseline and after 8 months of treatment (cumulative Dar dose 11.1 µg/kg b.w.) brachial and common carotid artery distensibility coefficients, aortic pulse wave velocity, brachial artery flow-mediated and nitroglycerin-mediated vasodilation were measured as well as the following biomarkers of vascular function: vWF, sVCAM, sICAM, E-selectin, t-PA and PAI-1.

RESULTS

23 patients in the Dar group and 17 patients in the Co group were available for per-protocol analysis. Hemoglobin increased significantly from 10.9 to 12.6 g/dl after 8 months in the Dar group, whereas it remained stable at 11.3 g/dl in the Co group. Effects on large artery stiffness, endothelial function and biomarkers of vascular function did not differ significantly between the two groups.

CONCLUSION

Therapy with Dar during 8 months did not significantly impact parameters of large artery stiffness and endothelial function in RTR. These data suggest that therapy with erythropoietin does not deteriorate arterial stiffness and endothelial function in RTR.

Pleiotropic vasoprotective effects of statins: the chicken or the egg?

Statins (3-hydroxy-3-methyl glutaryl coenzyme A [HMG-CoA] reductase inhibitors) are the most commonly used lipid-lowering drugs. Their main lipid-lowering effect is achieved by an increase in the expression of low-density lipoprotein cholesterol receptors associated with inhibition of cholesterol synthesis through inhibition of HMG-CoA reductase - the first and rate-limiting step in cholesterol synthesis. However, beyond cholesterol synthesis inhibition, inhibition of the HMG-CoA reductase affects as well the synthesis of other molecules with significant roles in different, yet often intercalating, metabolic pathways. On this basis, and supported by an increasing series of advocating epidemiological and experimental data, an extended dialogue has been established over the last few years regarding the nonlipid or "pleiotropic" actions of statins.

HMG CoA reductase inhibitors (statins) for kidney transplant recipients

BACKGROUND

Cardiovascular deaths account for the majority of deaths in kidney transplant recipients and dyslipidaemia contributes significantly to their cardiovascular disease. Statins are widely used in kidney transplant patients given their established benefits in the general population, however evidence favouring their use is lacking.

OBJECTIVES

To assess the benefits and harms of statin therapy on mortality and renal outcomes in kidney transplant recipients.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), and hand searched reference lists of articles and scientific proceedings.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing statins with placebo, no treatment or other statins in kidney transplant recipients.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. Statistical analyses were performed using the random effects model after testing for heterogeneity. Results were expressed as mean difference (MD) for continuous outcomes (lipid parameters) and risk ratio (RR) for dichotomous outcomes (mortality, allograft rejection, liver enzymes, occurrence of rhabdomyolysis and study withdrawal) with 95% confidence intervals (CI).

MAIN RESULTS

Sixteen studies (3229 patients) comparing statins versus placebo (15) or another statin (1) were included. Compared to placebo, statins did not decrease all-cause mortality (14 studies: RR 1.30, 95% CI 0.54 to 3.12). Point estimates favoured statins in terms of cardiovascular mortality (13 studies: RR 0.68, 95% CI 0.46 to 1.03) and non-fatal cardiovascular events (1 study: RR 0.70, 95% CI 0.48 to 1.01), however the results were not statistically significant. Compared to placebo, the use of statins was associated with a significantly lower end of treatment average total cholesterol (10 studies: MD -42.33 mg/dL (1.26 mmol/L), 95% CI -53.02 to -31.64), LDL cholesterol (10 studies: MD -46.15 mg/dL (1.19 mmol/L), 95% CI -55.97 to -36.33) and triglycerides (10 studies: MD -25.46 mg/dL (0.26 mmol/L), 95% CI -33.95 to 16.9). There was no significant difference in the risk of acute rejection (5 studies: RR 0.61; 95% C.I.0.32 to 1.16.) No data on chronic rejection was available and no major toxicity was noted.

AUTHORS' CONCLUSIONS

Statins significantly reduced hyperlipidaemia and tended to reduce cardiovascular events in kidney transplant recipients, but no effect has yet been demonstrated for mortality outcomes. Most of the data was derived from one large long-term study. Considering the significant impact of statins on all-cause and cardiovascular mortality in the general and predialysis populations, more studies are needed in kidney transplant patients.

Clinical factors associated with brachial-ankle pulse wave velocity in patients on maintenance hemodialysis

Pulse wave velocity (PWV) is a main parameter for arterial stiffness. In patients with end-stage renal disease (ESRD), PWV is known to be associated with increased mortality. But factors related to the increased PWV in ESRD patients are not well defined. In addition, the carotid-femoral PWV (cfPWV) measurement, which traditionally has been used to evaluate arterial stiffness, has low reproducibility. Recently, brachial-ankle PWV (baPWV) measurement, which can be performed more easily than cfPWV measurement, has become available as a means of measuring PWV. The aim of this study is to investigate the clinical factors associated with increased baPWV in ESRD patients. BaPWV was examined for 65 ESRD patients on maintenance hemodialysis during the period between the 7(th) to the 11(th) of February in 2005 using VP-1000. The clinical factors included age, sex, smoking history, blood pressure, diabetes, body mass index, interdialytic weight gain, duration of dialysis, lipid profile, uric acid, albumin, creatinine, C-reactive protein, calcium, phosphate, intact parathyroid hormone, and hematocrit were analyzed regarding associations (or to determine associations) with baPWV. The median age was 53.8±12.0, 31 males and 34 females. BaPWV was 18.9±5.2 m/s and there was no significant difference between gender (18.1±4.4 m/s vs 19.4±5.9 m/s, p=NS). In multiple regression models, age, predialysis systolic blood pressure, and diabetes were independent variables. In conclusion, age, systolic blood pressure, and diabetes were correlated with baPWV in ESRD patients. Thus baPWV measured by simple, noninvasive methods may become available for screening high risk groups in ESRD patients, although further longitudinal studies are necessary.

Optimal medical management of peripheral arterial disease

Patients with peripheral vascular disease are less likely to receive optimal medical management than patients with coronary artery disease. However, early medical treatment is critical because it is profoundly beneficial and the benefits are maximized. Even in patients with advanced disease requiring invasive intervention, medical management has been proven to improve outcome, prolong the success of the intervention, improve functional capacity, and prolong life. The vascular surgeon should be knowledgeable enough to initiate basic medical therapy and to define for their patients the goals that need to be met to optimize their medical management. The vascular surgeon should be instrumental in assuring that the peripheral vascular patient receives medical therapy of the same standard as the patient with coronary disease. The major modifiable risk factors in the vascular patient are: smoking, high blood pressure, hyperlipidemia, physical inactivity, obesity, and diabetes. In addition, the use of beta blockers for patients with coronary disease and antiplatelet therapy as well as angiotensin-converting enzyme (ACE) inhibitors are recommended for all patients with peripheral vascular disease. Statins have favorable effects on multiple interrelated aspects of vascular biology important in atherosclerosis. In particular they have beneficial effects on inflammation, plaque stabilization, endothelial dysfunction, and thrombosis. Statins have also been shown to be beneficial in acute vascular events. Angiotensin-converting enzyme inhibitors have been shown to reduce cardiovascular morbidity and mortality in patients with peripheral arterial disease regardless of the presence or absence of hypertension. A number of the pleiotropic effects of statins are shared by ACE inhibitors. In summary, patients with known vascular disease should be treated aggressively with a combination of a HMG CoA reductase inhibitor, an angiotensin-converting enzyme inhibitor, an antiplatelet agent and a beta blocker if there is a history of coronary disease. They should also receive tight control of their blood pressure and blood sugar. Smokers should be encouraged to stop smoking and should be provided with pharmaceutical and emotional support by their physicians. All of these patients should have their body mass index as close to normal as possible and be on a therapeutic lifestyle diet. Regular aerobic exercise is also indicated. Patients with symptomatic claudication should be considered for cilostazol. Patients with multiple risk factors for vascular disease, but who do not have documented disease should also be on statin therapy. As more studies define the linear relationship between lower LDL-C levels and lowered risk of vascular events, indicating that the lower the LDL-C level, the lower the risk, experts are advocating more aggressive lipid-lowering therapy. In patients with peripheral arterial disease, some experts now advocate lowering the goal of LDL therapy to 70 mg/dL.

Effect of Atorvastatin Therapy and Conversion to Tacrolimus on Hypercholesterolemia and Endothelial Dysfunction After Renal Transplantation

BACKGROUND

Hypercholesterolemia is a frequent complication in renal transplant patients treated with cyclosporine A (CsA). Whether it is preferable to treat hypercholesterolemia with statins or to switch patients from CsA to tacrolimus (TRL) has not been investigated.

METHODS

Twelve CsA-treated kidney transplant recipients with hypercholesterolemia were successively crossed over from CsA alone to: CsA plus atorvastatin; TRL alone; and TRL plus atorvastatin. Total cholesterol (C), Low density lipoprotein (LDL)-C, high density lipoprotein (HDL)-C, LDL and HDL alpha-tocopherol content, lag-time of LDL oxidation, plasma levels of oxidized LDL and the percentage of small dense LDL were assayed at the end of each treatment period. Endothelial function was assessed by high resolution ultrasound measurement of flow-mediated brachial artery vasodilatation (FMD).

RESULTS

Atorvastatin therapy was more efficient in reducing total cholesterol and LDL-C levels than conversion from CsA to TRL. Combining TRL with atorvastatin further reduced LDL-C levels as compared to TRL alone, but was no more efficient than the CsA-statin combination. Neither atorvastatin therapy nor conversion to TRL significantly changed the proportion of dense LDL, lipoprotein alpha-tocopherol contents or the lag time of LDL oxidation. Addition of atorvastatin to CsA increased FMD from 4.0+/-1.8% to 6.5+/-4.0% (P<0.05 vs. CsA). Conversion from CsA to TRL caused a slight improvement in FMD (5.1+/-2.1%, P<0.05 vs. CsA). Adding atorvastatin to TRL had no detectable effect on FMD (5.5+/-2.3%, P=NS vs. TRL).

CONCLUSIONS

Atorvastatin was more efficient in reducing total and LDL cholesterol levels of CsA-treated renal transplant patients than conversion to TRL and significantly improved endothelial dysfunction.

Impaired endothelium-dependent and -independent vasodilation in elderly patients with chronic heart failure

BACKGROUND

Impaired endothelium-dependent and independent vasodilator responses in chronic heart failure (CHF) have been well described. Previous studies involved younger patients and omitted medications prior to study.

AIMS

We explored if new therapeutic interventions would restore vasodilator responses in typical patients with chronic heart failure.

METHODS AND RESULTS

24 patients and 15 controls were recruited, patients were maintained on their usual medications. Forearm blood flow responses were measured by venous occlusion plethysmography in response to incremental doses of sodium nitroprusside (SNP) (6, 9 and 12 nmol/min), acetylcholine (ACH) (120, 180 and 240 nmol/min), angiotensin II (AII) (1, 10 and 100 nmol/min) and N(g)-Nitro-L-arginine methyl ester (L-NAME) (1, 2 and 4 nmol/min) infused into the non-dominant brachial artery. FBF responses to SNP were impaired in patients compared with controls (13.7(9.9,17.4) vs. 24.8(18.6,30.9)) arbitrary units, P<0.001). Similarly FBF responses to ACH were reduced in patients compared with controls (7.5(4.2,10.9) vs. 24.8(16.4,33.2)) arbitrary units, P<0.001. Decreased FBF was noted in response to AII and L-NAME but was significant only for AII and did not differ between groups.

CONCLUSIONS

In elderly patients with CHF, endothelium-dependent and independent vasodilator responses were blunted compared with controls. Defects in nitric oxide bioavailability and smooth muscle responsiveness are not reversed by modern medical management of the heart failure syndrome.

Statins in nephrotic syndrome: a new weapon against tissue injury

The nephrotic syndrome is characterized by metabolic disorders leading to an increase in circulating lipoproteins levels. Hypertriglyceridemia and hypercholesterolemia in this case may depend on a reduction in triglyceride-rich lipoproteins catabolism and on an increase in hepatic synthesis of Apo B-containing lipoproteins. These alterations are the starting point of a self-maintaining mechanism, which can accelerate the progression of chronic renal failure. Indeed, hyperlipidemia can affect renal function, increase proteinuria and speed glomerulosclerosis, thus determining a higher risk of progression to dialysis. 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase is the rate-limiting enzyme in cholesterol synthesis from mevalonate and its inhibitors, or statins, can therefore interfere with the above-mentioned consequences of hyperlipidemia. Statins are already well known for their effectiveness on primary cardiovascular prevention, which cannot be explained only through their hypolipemic effect. As far as kidney diseases are concerned, statin therapy has been shown to prevent creatinine clearance decline and to slow renal function loss, particularly in case of proteinuria, and its favorable effect may depend only partially on the attenuation of hyperlipidemia. Statins may therefore confer tissue protection through lipid-independent mechanisms, which can be triggered by other mediators, such as angiotensin receptor blockers. Possible pathways for the protective action of statins, other than any hypocholesterolemic effect, are: cellular apoptosis/proliferation balance, inflammatory cytokines production, and signal transduction regulation. Statins also play a role in the regulation of the inflammatory and immune response, coagulation process, bone turnover, neovascularization, vascular tone, and arterial pressure. In this study, we would like to provide scientific evidences for the pleiotropic effects of statins, which could be the starting point for the development of new therapeutical strategies in different clinical areas.

Fluvastatin in the treatment of dyslipidemia associated with chronic kidney failure and renal transplantation

Premature atherosclerotic coronary heart disease driven by multiple risk factors is a major cause of morbidity and mortality among the 6 million patients in the United States with chronic renal failure. Consensus is that kidney failure and renal transplantation patients should be treated aggressively for dyslipidemia. Major medical literature databases were searched for published information about fluvastatin, a HMG-CoA reductase inhibitor, used in patients with impaired renal function. This article characterizes the dyslipidemia observed in these clinical settings and reviews the clinical experience with fluvastatin.

A review of the lipid-related effects of fluvastatin

BACKGROUND

Statin therapy has been shown to significantly decrease vascular events and overall mortality in primary and secondary prevention trials. This review considers the pharmacology, nonlipid-lowering effects and clinical trial evidence of fluvastatin based on a survey of PubMed entries.

FINDINGS

Recent clinical data show that treatment with fluvastatin is associated with a variety of benefits in different high-risk populations along with a good safety profile. Fluvastatin exerts non-lipid lowering-associated pleiotropic effects in both clinical and experimental studies. Furthermore, an extended-release formulation of fluvastatin with a favourable pharmacokinetic profile is available.

CONCLUSION

Treatment with fluvastatin offers a convenient, safe and evidence-based approach to managing dyslipidaemias and preventing vascular events.

Assessment of flow-mediated vasodilatation (FMD) of the brachial artery: effects of technical aspects of the FMD measurement on the FMD response

AIMS

The ability to assess endothelial function non-invasively with B-mode ultrasound has lead to its widespread application in a variety of studies. However, the absolute values obtained using this approach vary considerably across studies. We studied whether technical aspects of the methodology can explain the wide variety in absolute values across studies.

METHODS AND RESULTS

A literature search was performed to identify published reports on flow-mediated vasodilatation (FMD) of the brachial artery published between 1992 and 2001. Information on type of equipment (wall track/B-mode), location of the measurement (antecubital fossa/upper arm), occlusion site (lower/upper arm), occlusion duration (min), and occlusion pressure was extracted. Patient characteristics were also extracted. For the healthy populations, mean FMD varied from 0.20 to 19.2%; for the coronary heart disease (CHD) patients FMD varied from -1.3 to 14%; for subjects with diabetes mellitus FMD varied from 0.75 to 12%. Compared with occlusion at the upper arm, lower arm occlusion was related to decreased FMD (mean difference in FMD -2.47%; 95% CI 0.55-4.39). An occlusion duration of > or =4.5 min was related to an increased FMD compared with an occlusion time of < or =4 min (mean difference 1.30%; 95% CI 0.35-2.46). These findings were adjusted for other technical aspects of the methodology and for differences in risk factors between populations.

CONCLUSION

Mean FMD differs widely between studies. There is a great overlap between populations (healthy, CHD, diabetics). Our findings suggest that the technical aspects of the measurements, the location, and the duration of the occlusion may explain some of these differences, whereas type of equipment, location of the measurement, and occlusion pressure do not.

Fluvastatin and fluvastatin extended release: a clinical and safety profile

Cardiovascular diseases due to atherosclerosis are the leading causes of mortality in the Western world. Cholesterol-lowering therapy with 3-hydroxy-3-methylglutaryl coenzyme Areductase inhibitors (statins) has demonstrated a reduction in cardiovascular morbidity and mortality in diverse populations. Fluvastatin (Lescol, Novartis Pharmaceuticals) was the first totally synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor on the market and has recently become available in an extended-release formulation (Lescol XL, Novartis Pharmaceuticals). Data from several clinical outcome trials have shown substantial benefits from fluvastatin treatment in diverse populations. Fluvastatin exists primarily in its acid form and as inactive metabolites in vivo, while active metabolites as well as the lactone form are only present in small amounts. The demonstration of the safe use of fluvastatin in a wide range of patients may be associated with the predominant acid form of the drug in vivo, as well as its predominant metabolism via the cytochrome P450 2C9 pathway.

Fluvastatin: clinical and safety profile

Therapy with HMG-CoA reductase inhibitors (statins) has been shown to significantly reduce major coronary events and death in a wide range of individuals at risk for these events. In addition, recent observations suggest that some of the clinical benefits associated with statin therapy may be pleiotropic; that is, independent of their cholesterol-inhibiting action. It is clear that the clinical benefits associated with statin therapy far outweigh the risks; however, there may be important clinical differences among agents within the class, related to both benefits and drug safety. Evaluation of the benefit-to-risk profile for each available statin should include considering the results of randomised clinical outcome trials, the safety record of each agent, effect on lipoproteins and evidence of beneficial pleiotropic properties.Recently, data from several clinical outcome trials have shown that substantial benefits are associated with treatment with fluvastatin in diverse populations. In particular, data from two large, randomised clinical trials have demonstrated that fluvastatin is effective for secondary prevention of cardiac events in patients following coronary intervention procedures, and for primary prevention of cardiac events in renal transplant recipients. Pleiotropic benefits for fluvastatin have been shown in experimental and clinical studies as well. Fluvastatin was the first statin available as an extended-release product (fluvastatin XL 80mg); both formulations have demonstrated efficacy and safety in a wide range of patients. Taken together, these clinical outcomes and safety data suggest a strong benefit-to-risk profile for fluvastatin.

Statin use after renal transplantation: a systematic quality review of trial-based evidence

BACKGROUND AND OBJECTIVES

HMG-CoA reductase inhibitor (statin) therapy reduces cardiovascular risk in the general population and may modulate rejection in solid organ transplant recipients. We assessed whether current clinical evidence supports the use of statins to improve cardiac and/or renal outcomes after kidney transplantation.

METHODS

We performed a systematic review of randomized, controlled intervention trials of statins among renal allograft recipients. Clinical trials published between January 1, 1993 and January 1, 2004 were identified by systematic search of electronic databases. Eligible studies measured the impact of therapy on acute allograft rejection, surrogates of cardiovascular risk and/or cardiovascular morbidity and mortality. We abstracted descriptive summaries of trial design elements and primary effect estimates, and assessed trial quality with a standardized quality evaluation tool.

RESULTS

Thirteen eligible trials were identified. Statin therapy was associated with less acute allograft rejection in two early studies but was ineffective in three subsequent, larger trials. Therapeutic benefit was also seen in six of seven small studies that evaluated cardiovascular risk surrogates. Statin use did not significantly alter the primary composite outcome in a single large cardiac events trial, but was associated with reductions in secondary end-points of cardiac death analysed alone or with myocardial infarction. Important design distinctions included statin preparation and dose, concomitant interventions, study power and randomization methods. Median total quality scores were 52 for the rejection trials, 41 for the studies of cardiovascular risk surrogates and 69 for the cardiac events trial, and showed a trend towards variation by outcome measure (P = 0.05).

CONCLUSIONS

Heterogeneous study designs and methodological quality contribute to discrepant conclusions on the benefit of statin therapy to renal allograft recipients. Trial-based clinical evidence does not support the use of statins to lower acute rejection risk after kidney transplantation, but does indicate effectiveness for improvement in cardiovascular risk markers and possibly for reduction of clinical cardiac events.

Successful renal transplantation decreases aortic stiffness and increases vascular reactivity in dialysis patients

BACKGROUND

Patients with end-stage renal disease on dialysis have among the highest cardiovascular event rates documented. Abnormal nitric oxide (NO)-dependent endothelial reactivity and increased arterial stiffness are commonly described in hemodialysis (HD) patients. Measures of aortic stiffness--aortic pulse wave velocity (PWV) and augmentation index (AGI)--have been shown to be powerful predictors of survival on hemodialysis. It is not known how these parameters interfere with successful renal transplantation.

METHODS

PWV and aortic AGI (difference between the first and second systolic peak on the aortic pressure waveform divided by the pulse wave height) were determined from contour analysis of arterial waveforms recorded by applanation tonometry using a SphygmoCor device in 41 HD patients (20 men; age, 41.8 years) and in a control group of 20 patients with essential hypertension (HTA) (10 men; age, 43.6 years). Twenty of the HD patients (10 men; age, 39.7 years) received live-related renal transplants (RTx) and were restudied (3 months after RTx, normal serum creatinine). NO-dependent and NO-independent vascular reactivity were assessed by changes in AGI after challenges with inhaled salbutamol (SAL) and sublingual nitroglycerin (NTG), respectively.

RESULTS

AGI values were significantly lower in RTx patients compared with subjects on hemodialysis (15.9 +/- 13.9% vs. 27.9 +/- 11.9%, P<0.05), but similar to essential HTA controls (16.5 +/- 17%). Serial AGI measurements showed that successful renal transplantation is associated with a decrease in AGI in all cases, from a mean of 25.1 +/- 7.8% while on dialysis to 15.9 +/- 7.0% 3 months after transplantation (P<0.0001). The responsiveness to both endothelium-dependent stimuli (inhaled SAL) and endothelium-independent stimuli (sublingual NTG) was greater in transplant patients than in hemodialysis patients (SAL-induced decrease in AGI -82.3 +/- 65.7% vs. 45 +/- 72.3%, P<0.01; and NTG-induced decrease in AGI 197 +/- 108 vs. -129.0 +/- 215.5%, P<0.01). PWV values in dialysis patients (7.19 +/- 1.88 m/sec) were significantly higher than those measured in essential HTA patients (6.34 +/- 1.32 m/sec, P<0.05) with normal renal function (despite similar blood pressure levels). PWV after RTx was 6.59 +/- 1.62 m/sec, significantly different from pretransplantation (dialysis) values (P<0.05 for comparison) but similar to the control group of essential HTA patients.

CONCLUSIONS

Renal transplantation is associated with marked improvements in vascular structure and function to a profile comparable to essential HTA patients.

Fluvastatin reduces atherogenic lipids without any effect on native endothelial function early after kidney transplantation

BACKGROUND

Cardiovascular risk is greatly increased in renal transplant recipients. 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor (statin) therapy may reduce cardiovascular risk by improving both dyslipidemia and endothelial function. We therefore performed this study to assess the effect of fluvastatin on endothelial function in renal transplant recipients.

METHODS

This randomized, placebo-controlled, double-blind designed study investigated the effect of fluvastatin on endothelial function. Thirty-seven recipients received fluvastatin 40 mg/d and 35 received placebo during the first 12 wk following transplantation. All patients initially received cyclosporin A, prednisolone and azathioprine. At the end of treatment, endothelial function was assessed in the forearm skin microvasculature by laser Doppler flowmetry following acetylcholine stimulation. Samples were taken for measurements of serum lipids and vasoactive markers.

RESULTS

There were no differences in endothelial function between fluvastatin recipients and controls, AUCACh was 656 +/- 479 and 627 +/- 518 AU min, respectively (fluv vs. control, p > 0.65). In the placebo limb, total cholesterol and LDL cholesterol increased 22 +/- 12% and 22 +/- 18%, respectively in the first 12 wk following transplantation. The respective values were 18 +/- 13% (p = 0.010) and 34 +/- 19% (p = 0.0013) lower at 12 wk in the fluvastatin treated patients. Plasma ET-1, BigET-1 and urinary excretion of cGMP were not significantly different between treatment groups (p > 0.55).

CONCLUSION

Although fluvastatin 40 mg/d significantly lowers cholesterol it does not affect endothelial function the first 3 months after renal transplantation. The lack of effect on endothelial function is consistent with a lack of effect on vasoactive substances.

Effect of a 3-year therapy with the 3-hydroxy-3-methylglutaryl coenzyme a reductase-inhibitor fluvastatin on endothelial function and distensibility of large arteries in hypercholesterolemic renal transplant recipient

BACKGROUND

In patients after renal transplantation functional arterial vessel wall properties are impaired. Whether 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors have a sustained effect on endothelial function and arterial distensibility in patients after renal transplantation is not clear. The authors studied the effects of a long-term therapy with fluvastatin on large artery distensibility and flow-mediated vasodilation (FMD) in hypercholesterolemic patients after renal transplantation in a prospective, blinded, and randomized trial.

METHODS

Twenty-six patients who had undergone renal transplantation were assigned randomly to either fluvastatin, 40 mg/d (n = 13) or placebo (n = 13) and underwent follow-up for 3 years. At baseline and after 6, 12, and 36 months of treatment, carotid and brachial artery distensibility, endothelium-dependent FMD, and nitroglycerine-induced vasodilation (NMD) of the brachial artery were measured by a echo-tracking device.

RESULTS

A significant decrease in total and low-density cholesterol was observed after 6, 12, and 36 months in patients treated with fluvastatin but not in the placebo group. FMD increased with fluvastatin from 4.6 +/- 2% to 12.4 +/- 2% after 12 months; this improvement was sustained with 13.4 +/- 3% after 36 months (P < 0.05). However, placebo did not alter FMD (P < 0.001 for trend difference between groups by analysis of covariance). Endothelium-independent NMD was similar in both groups at baseline and during therapy. Neither carotid nor brachial artery distensibility coefficients were altered by either treatment.

CONCLUSION

HMG-CoA reductase inhibitor therapy over 3 years results in a significant and sustained improvement of endothelial function in hypercholesterolemic patients after renal transplantation. However, this is not accompanied by a beneficial effect on impaired large artery distensibility even after long-term therapy with fluvastatin.

Vascular function in children after renal transplantation

BACKGROUND

Atherosclerotic complications are the main cause of death in adult patients with renal failure. Endothelial dysfunction is a hallmark of early atherosclerotic changes. The numerous risk factors for endothelial dysfunction present in adults are present in children with renal failure, as well. In addition to this, increased stiffness of the arterial tree conveys an increased risk for cardiovascular mortality. The aim of this study is to investigate whether pediatric kidney recipients already show endothelial dysfunction and have increased arterial stiffness.

METHODS

We investigated 20 pediatric kidney recipients with stable graft function and 20 healthy children. Endothelial function was studied noninvasively with ultrasound and digital signal analysis equipment as the percentage of post-ischemic flow-mediated dilatation (FMD) of the brachial artery. Parameters of arterial distensibility were calculated from distension of the brachial artery during the cardiac cycle, pulse pressure, and baseline diameter.

RESULTS

FMD was significantly less in patients (7.7% +/- 5.4%) than controls (15.0% +/- 7.1%; P < 0.001), indicating endothelial dysfunction in pediatric kidney recipients. Impairment of FMD was found predominantly in patients being treated for hypertension. Arterial distensibility was diminished in patients (3.4 +/- 2.8 versus 5.7 +/- 3.3 10(-3)/mm Hg; P < 0.02), indicating increased stiffness of the arterial tree. Patients had a greater baseline diameter of the brachial artery adjusted for height than healthy controls at equal blood pressure.

CONCLUSION

These findings suggest arterial wall changes in pediatric renal transplant recipients. They are already at risk for premature development of atherosclerotic complications and cardiovascular mortality.

Statins and renal function

Renal disease is often associated with an increased risk of vascular events. Moreover, an accelerated form of atherosclerosis commonly occurs in these patients. The reasons for these associations are not clearly defined but include the widespread presence of several established risk factors (eg, dyslipidemia, hypertension, and diabetes). Other predictors of atherosclerotic disease may also be abnormally elevated (eg, homocysteine, fibrinogen, and lipoprotein a). In addition, there is evidence that impaired renal function per se predicts vascular risk. Despite this high-risk background, the potential benefit of treatment with statins has not been widely investigated in these patients. The present review considers the evidence (experimental and clinical) that statins exert beneficial effects in patients with different types of renal disease. This includes improved renal function, decreased microalbuminuria, and a fall in blood pressure. Statins may also improve renal allograft survival. The potential mechanisms mediating these effects are considered. The interactions between statins and several risk factors that may be present in patients with impaired renal function are also considered. There is an urgent need to define the role of statins in these high-risk patients. Which is the statin of choice? This question is relevant because impaired renal function can interfere with statin pharmacokinetics. Furthermore, other drugs administered to these patients may cause serious interactions with statins.

Immunomodulatory effects of statins: mechanisms and potential impact on arteriosclerosis

Clinical trials with statins have demonstrated a marked reduction of cardiovascular mortality. However, it remains controversial whether these clinical benefits stem from powerful cholesterol-lowering effects of statins or whether they are due in part to their cholesterol-independent effects on vascular function, plaque growth, plaque rupture, or thrombosis. The identification of several mechanisms through which statins decrease the recruitment of monocytes and T cells into the arterial wall and inhibit T cell activation and proliferation in vitro have prompted speculations that immunomodulatory effects of statins may be beneficial in recipients of organ transplants. Hypercholesterolemia is frequent in these patients, and delayed-type hypersensitivity reactions in the arterial walls of the graft may be compounded by chronic inflammation associated with conventional atherogenesis. To assess the potential clinical relevance of immunomodulatory effects of statins, the role of the immune system in atherogenesis and the effects of statins in vitro in experimental models and in clinical trials will be reviewed. It is concluded that despite solid in vitro evidence, clinical evidence for an independent immunosuppressive effect of statins in organ transplant patients is presently insufficient; however, further investigation of their in vivo occurrence and clinical relevance is warranted.