Safety and efficacy of atorvastatin in heart transplant recipients

Management of dyslipidemia after allogeneic hematopoietic stem cell transplantation

Dyslipidemia is one of the complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT), and it is often underestimated and undertreated. Dyslipidemia in allo-HSCT recipients has been confirmed to be associated with endocrine dysfunction, acute and chronic graft-versus-host disease (aGVHD and cGVHD), immunosuppressive agent application, etc. However, few studies have illustrated the accurate molecular signaling pathways involved in dyslipidemia, and there are no standard guidelines for dyslipidemia management after HSCT. This review will discuss the pathogenesis of dyslipidemia, especially the association with aGVHD and/or cGVHD. Comprehensive treatment methods for dyslipidemia after HSCT will also be summarized.

Statin intensity and risk for cardiovascular events after heart transplantation

AIMS

Statins improve survival and reduce rejection and cardiac allograft vasculopathy after heart transplantation (HT). The impact of different statin intensities on clinical outcomes has never been assessed. We set out to determine the impact of statin exposure on cardiovascular outcomes after HT.

METHODS AND RESULTS

We performed a retrospective study of 346 adult patients who underwent HT from 2006 to 2018. Statin intensity was determined longitudinally after HT based on American College of Cardiology/American Heart Association (ACC/AHA) guidelines. The primary outcome was the time to the first primary event defined as the composite of heart failure hospitalization, myocardial infarction, revascularization, and all-cause mortality. Secondary outcomes included time to significant rejection and time to moderate-severe cardiac allograft vasculopathy. Adverse events were evaluated for subjects on high-intensity statin therapy. A Cox proportional hazards model was used to evaluate the relationship between clinical variables, statin intensity, and outcomes. Most subjects were treated with low-intensity statin therapy although this declined from 89.9% of the population at 1month after HT to 42.8% at 5years after HT. History of ischaemic cardiomyopathy, significant acute rejection, older donor age, and lesser statin intensity (p ≤ 0.001) were associated with reduced time to the primary outcome in a multivariable Cox model. Greater intensity of statin therapy was most beneficial early after HT. There were no statin-related adverse events for the 14 subjects on high-intensity statin therapy.

CONCLUSIONS

Greater statin intensity was associated with a reduction in adverse cardiovascular outcomes after HT.

Statin Safety and Associated Adverse Events: A Scientific Statement From the American Heart Association

One in 4 Americans >40 years of age takes a statin to reduce the risk of myocardial infarction, ischemic stroke, and other complications of atherosclerotic disease. The most effective statins produce a mean reduction in low-density lipoprotein cholesterol of 55% to 60% at the maximum dosage, and 6 of the 7 marketed statins are available in generic form, which makes them affordable for most patients. Primarily using data from randomized controlled trials, supplemented with observational data where necessary, this scientific statement provides a comprehensive review of statin safety and tolerability. The review covers the general patient population, as well as demographic subgroups, including the elderly, children, pregnant women, East Asians, and patients with specific conditions such as chronic disease of the kidney and liver, human immunodeficiency viral infection, and organ transplants. The risk of statin-induced serious muscle injury, including rhabdomyolysis, is <0.1%, and the risk of serious hepatotoxicity is ≈0.001%. The risk of statin-induced newly diagnosed diabetes mellitus is ≈0.2% per year of treatment, depending on the underlying risk of diabetes mellitus in the population studied. In patients with cerebrovascular disease, statins possibly increase the risk of hemorrhagic stroke; however, they clearly produce a greater reduction in the risk of atherothrombotic stroke and thus total stroke, as well as other cardiovascular events. There is no convincing evidence for a causal relationship between statins and cancer, cataracts, cognitive dysfunction, peripheral neuropathy, erectile dysfunction, or tendonitis. In US clinical practices, roughly 10% of patients stop taking a statin because of subjective complaints, most commonly muscle symptoms without raised creatine kinase. In contrast, in randomized clinical trials, the difference in the incidence of muscle symptoms without significantly raised creatinine kinase in statin-treated compared with placebo-treated participants is <1%, and it is even smaller (0.1%) for patients who discontinued treatment because of such muscle symptoms. This suggests that muscle symptoms are usually not caused by pharmacological effects of the statin. Restarting statin therapy in these patients can be challenging, but it is important, especially in patients at high risk of cardiovascular events, for whom prevention of these events is a priority. Overall, in patients for whom statin treatment is recommended by current guidelines, the benefits greatly outweigh the risks.

The role of statins in patients after heart transplantation

Numerous studies have shown that statin therapy initiated early after heart transplantation improves the short- and long-term prognosis, leading to a reduction in the incidence of cardiac allograft vasculopathy (CAV), acute rejection episodes and significantly lowers the incidence of cancer in this patient population. The molecular mechanisms responsible for the beneficial effects of statins in patients after heart transplantation are complex; the effectiveness of statins is associated not only with their hypolipemic action, but also with their pleiotropic properties. Statins have been shown to exert protective and therapeutic effects against cancer because they act as antiproliferative agents, promoting apoptosis and inhibiting angiogenesis. Moreover, they reduce the number of circulating monocytes, which inhibits the secretion of proinflammatory cytokines, growth factors, adhesion molecules, chemokines, and matrix metalloproteinases, preventing chronic rejection and CAV. For these reasons, statins should be used as part of standard therapy in patients after heart transplantation.

Incidence of adverse events with HMG-CoA reductase inhibitors in liver transplant patients

Transplant patients are at increased risk of developing dyslipidemia, which contributes to coronary artery disease and cardiovascular events. The purpose of this study was to explore documented adverse effects of liver transplant recipients receiving lipid-lowering therapies.

METHODS

A retrospective chart review of 69 liver transplant patients was conducted to evaluate the incidence of adverse effects, especially rhabdomyolysis and liver function abnormalities, in liver transplant patients treated with a lipid lowering agent (LLA). Data were collected from the time of initiation of LLA to 12 months later, looking at the type, dose, and duration of LLA, concurrent cytochrome P450 inhibitors, immunosuppression used, and laboratory parameters.

RESULTS

For HMG-CoA reductase inhibitor therapy, simvistatin was used in five (7.8%) patients, pravastatin in 40 (62.5%), fluvastatin in one (1.6%), atorvastatin in five (7.8%), and lovastatin in three (4.7%). Gemfibrozil, a fibric acid derivative, was employed as monotherapy in 10 (15.6%) of patients. There were five patients who received combination therapy with a fibric acid derivative, four (80%) with gemfibrozil + pravastatin, and one (20%) with gemfibrozil + simvastatin. Six patients studied had adverse effects, five (7.2%) with myalgia and one (1.4%) with myopathy. LLA monotherapy with either pravastatin or atorvastatin was used in these patients. The five patients with myalgia were on concurrent therapy with cyclosporin, and the patient with myopathy was on concurrent cyclosporin + diltiazem therapy, both of which are P450 inhibitors. One out of 23 patients on a non-immunosuppressant P450 inhibitor developed adverse effects. No significant elevation of alanine aminotransferase, aspartate aminotransferase, or alkaline phosphatase was noted in any patient.

CONCLUSIONS

Overall, there was a general tolerability with a low incidence of adverse events, no incidence of severe complications, and no alterations in liver function tests in the study population with the use of LLA.

Lipid-lowering agents that cause drug-induced hepatotoxicity

The effort to reduce cardiovascular risk factors, including hyperlipidemia, has led to the increased use of lipid-lowering agents. Hyperlipidemic patients often have underlying fatty liver disease, however, and thus may have elevated and fluctuating liver biochemistries. Therefore, caution should be applied before attributing elevated liver tests to lipid-lowering agents. Data indicate that patients who have chronic liver disease and compensated cirrhosis should not be precluded from receiving statins to treat hyperlipidemia. Several recent studies and expert opinion currently fully endorse statin use in patients who have nonalcoholic fatty liver disease and other chronic liver disease if clinically indicated.

Atorvastatin affects interleukin-2 signaling by altering the lipid raft enrichment of the interleukin-2 receptor beta chain

Although the immunomodulatory properties of statins are in part independent of their lipid-lowering effects, cholesterol is a major component of lipid rafts. We therefore studied the effects of atorvastatin (AS) on the raft enrichment of the interleukin-2 receptor (IL-2R) beta chain previously described by us and on early IL-2R signaling events in activated human T cells. We found that concomitant AS exposure during a 3-day stimulation with phytohemagglutinin (PHA) attenuates activation-associated events, such as the enhanced surface expression of the raft marker GM-1 and the induced expression of the activation marker CD25 (the IL-2R alpha chain). In contrast, brief AS treatment after PHA stimulation increased GM-1 surface expression and virtually abolished the selective raft enrichment of the IL-2R beta chain. Although this AS-associated increase in GM-1 expression resembled that seen in the presence of the raft-disrupting cholesterol chelator methyl-beta-cyclodextrin (MBCD), the two agents had contrasting effects on the tyrosine phosphorylation of the IL-2R beta chain by exogenous IL-2: MBCD essentially abolished this event, whereas AS tended to enhance it and shifted its occurrence out of rafts. We conclude that AS affects IL-2R signaling by altering the raft enrichment of the IL-2R beta chain and propose that this effect is one mechanism underlying the immunomodulatory properties of statins.

Safety of Statins When Response is Carefully Monitored: A Study of 336 Heart Recipients

BACKGROUND

Statins are used as first-line drugs against hypercholesterolemia after heart transplantation. Randomized clinical trials have shown that they reduce cholesterol levels, and the incidence of rejection and coronary vasculopathy. Adverse effects have been related to the use of certain statins, high statin dosages, comorbidities, and coadministration with cyclosporine. However, estimation of the risk of adverse effects for a given patient is difficult. The aims of this study were to determine the incidence of various kinds of adverse effect of statins; to evaluate certain potential risk factors; and to assess the efficacy of early response to signs of adverse effects.

METHODS

Between April 1991 and December 2003, we retrospectively evaluated 336 heart transplant patients (including 55 women) with regard to the occurrence of possible adverse effects of statins (rhabdomyolysis, myalgia, hepatotoxicity, high CK without muscle symptoms, and others). Resolution on reduction of dosage or discontinuance and/or change of statin were deemed to constitute confirmation of cause. Relations were sought between adverse effects and age, sex, immunosuppressive therapy, kidney failure, body mass index (BMI), arterial hypertension, and diabetes mellitus.

RESULTS

Possible adverse events of statins were suffered by 60 patients, all of them men. The causal role of statins was confirmed in 41 (12.2% of all 336): hepatotoxicity was suffered by 13, high CK without muscle ache or weakness by 18, rhabdomyolysis by 5, myalgia by 3, and other effects by 2. The incidence of confirmed statin-related complications was higher among patients with BMI >29 kg/m(2) than among those with lower BMI (P = .055). None of the patients with confirmed statin-related complications needed dialysis, none died, and permanent suspension of statin treatment was only necessary in 13 cases (3.9% of the 336).

CONCLUSIONS

Some 10% to 20% of HT patients appear to suffer adverse side effects of initial statin therapy. However, early detection of such effects through diligent clinical and analytical monitoring allows the therapy to be modified in time to minimize the appearance of severe complications. In only a minority of cases permanent suspension of statin therapy is necessary.

Metaanalysis of statins and survival in de novo cardiac transplantation

BACKGROUND

The use of HMG CoA reductase inhibitors (statins) after cardiac transplantation has been suggested to decrease the incidence of severe rejection and improve survival. Individual investigations that have led to this suggestion are randomized (but not placebo-controlled) studies, including small patient numbers that have (and thus underpowered) and enrolling heterogeneous subjects (including retransplant recipients). The purpose of this pooled analysis was to quantify the benefit of statins on survival in de novo cardiac transplant recipients.

METHODS

Medline (1966 to 2003) was queried using the keywords statin, HMG CoA reductase inhibitors, cardiac transplantation, transplant, cholesterol, atorvastatin, fluvastatin, lovastatin, pravastatin, and simvastatin. In addition, we searched the cited literature and previously published systematic reviews. Of 36 articles retrieved, 3 randomized controlled studies met our population inclusion criteria; namely age >18 years, de novo heart transplant recipients, statin therapy within 3 months, and > or = 1-year follow-up. Pooled data were metaanalyzed by Mantel-Haenszel tests using a random effects model that included tests for heterogeneity.

RESULTS

The three pooled studies included 246 patients (statin, n = 129; no statin, n = 117) and 27 events (11%). The pooled analysis demonstrated a significant reduction in mortality with statin use (RR 0.31; 95% CI 0.13 to 0.7; P = .006) without significant heterogeneity (P = .7) among the studies. Two of the three studies reported allograft rejection with hemodynamic compromise. The pooled analysis demonstrated a significant benefit on this endpoint (RR 0.22, 95% CI 0.08 to 0.63; P = .004).

CONCLUSION

This meta-analysis demonstrates that statin therapy decreases rejection episodes with hemodynamic consequences and improves 1-year heart transplant survival.

Plasma kinetics of a cholesterol-rich microemulsion in patients submitted to heart transplantation

BACKGROUND

Development of coronary graft disease is currently the main cause of late heart-transplantation (HT) failure. HT patients frequently show hypercholesterolemia as well as alterations in chylomicron metabolism. These postHT changes may be important in coronary graft disease development. To clarify whether hypercholesterolemia is caused by decreased low-density lipoprotein (LDL) removal from the plasma, we studied the plasma kinetics of a cholesterol-rich emulsion that binds to LDL receptor.

METHODS

We studied 13 HT patients and 13 healthy normolipidemic subjects paired for sex, age, and body mass index. An emulsion labeled with C-cholesteryl oleate was injected intravenously, and blood samples were collected in predetermined intervals (5 minutes, 1, 2, 4, 6, and 8 hours) to determine the radioactivity decay curves and to calculate the fractional clearance rates (FCR).

RESULTS

The plasma level of total cholesterol, LDL cholesterol, high-density lipoprotein cholesterol, and apo B were greater in HT group than in the control group (P<0.005). FCR C-cholesteryl oleate was smaller in HT patients when compared with the control group (P=0.02).

CONCLUSION

The results showed that HT patients have a deficiency in the mechanisms of LDL removal from the plasma, as tested by the cholesterol-rich emulsion, and this may be important in the development of coronary graft disease.

Treatment of hyperlipidemia in cardiac transplant recipients

Of the 60,000 patients receiving heart transplants between 1982 and 2001, approximately 12,000 are currently alive. The high incidence of hyperlipidemia and coronary disease (also known as accelerated graft atherosclerosis, or AGA) in these patients warrants early prophylaxis soon after transplantation with 3-hydroxy-3-methylglutaryl (HMG) Co-A reductase inhibitors (statins). Immunosuppressive agents such as prednisone, cyclosporine, mycophenylate mofetil, and sirolimus are associated with hyperlipidemia. Statins, in addition to lowering cholesterol levels, also benefit cardiac transplant recipients via effects on the immune system and endothelial function. Recent data have demonstrated that statins decrease AGA and mortality rates. Furthermore, greater benefits are seen when statins are started early. The 2 statins shown to decrease mortality in patients after cardiac transplantation are pravastatin and simvastatin, which differ in their metabolism (pravastatin is the only statin with non-cytochrome metabolism) and lipophilicity (pravastatin is less lipophilic). Although the benefit of simvastatin has been shown to extend to 8 years after transplantation, increased adverse effects in other studies with higher doses of simvastatin have resulted in new prescribing recommendations, which state that the dose of simvastatin should probably not exceed 10 mg with cyclosporine or gemfibrozil and 20 mg with amiodarone or verapamil. The evidence for potential benefits, interactions, and adverse effects of other potential lipid-lowering drugs for this patient population, such as fibrates, niacin, fish oil, cholestyramine, and ezetimibe, are also discussed. A summary algorithm is proposed, including approaches to patients with statin-associated musculoskeletal symptoms and patients with inadequate results after initial statin therapy.

Dyslipidemias and HMG-CoA Reductase Inhibitor Prescription in Heart Transplant Recipients

BACKGROUND:

The treatment of dyslipidemias in orthotopic heart transplant (OHT) recipients is not highlighted in the National Cholesterol Education Program Adult Treatment Panel guidelines. Emerging data suggest that hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) safely reduce the risk of transplant rejection and coronary artery vasculopathy in OHT patients.

OBJECTIVE:

To assess the proportion of patients from our institution reaching the low-density lipoprotein cholesterol (LDL-C) target of <100 mg/dL, evaluate the impact of statins in reaching this goal, and evaluate the prescribing practice for statins in US OHT centers.

METHODS:

The management of dyslipidemia of OHT recipients followed at our institution was retrospectively evaluated. In addition, the use of statins in adult OHT centers in the US that performed ≥1 5 OHTs per year was assessed through a survey.

RESULTS:

Of the 328 patients from our institution, 58.5% achieved an LDL-C <100 mg/dL. Patients prescribed statins were more likely to reach this goal (p < 0.01). A total of 85.0% of centers responding to the survey use statins as a part of their post-OHT protocol, primarily to reduce coronary artery vasculopathy (70.6%).

CONCLUSIONS:

Due to the potential for improved outcomes, a large proportion of patients are prescribed a statin. Our results support previous findings that statins are safe and effective in reducing LDL-C in the management of dyslipidemias in OHT recipients. Nonetheless, dyslipidemias are suboptimally managed in many post-OHT patients.

Strategies for minimizing hyperlipidemia after cardiac transplantation

Allograft coronary artery disease represents a major limitation to long-term survival after cardiac transplantation. Hyperlipidemias have been linked to the development of native coronary atherosclerosis, and hyperlipidemic states have correlated with the severity of allograft coronary artery disease. Heart transplant recipients typically manifest increases in plasma levels of total cholesterol, low-density lipoprotein-cholesterol (LDL-C), and triglycerides within the first 3-12 months following transplantation. Factors known to promote post-transplant hyperlipidemia include the use of corticosteroids, cyclosporine (interference with clearance and increased oxidizability of LDL), sirolimus (hypertriglyceridemia), and patient-specific causes of hyperlipidemia which contributed to their underlying heart disease. Hydroxymethylglutaryl coenzyme-A (HMG-CoA) reductase inhibitors are the foundation of antilipid therapy following cardiac transplantation. Pravastatin is effective in lowering plasma cholesterol levels and is associated with a decreased incidence and progression of allograft coronary artery disease. All HMG-CoA reductase inhibitors except pravastatin are metabolized by the hepatic cytochrome P450 system which metabolizes cyclosporine, increasing the risk of myostitis when they are used in large dosages with cyclosporine. Simvastatin, atorvastatin and fluvastatin have been studied in heart transplant recipients. Gemfibrozil has proved effective in transplant recipients when there is isolated marked elevation of plasma triglyceride levels. When hyperlipidemia persists despite therapy, some benefit may result with conversion from cyclosporine to tacrolimus. Although a definitive link between hyperlipidemia and allograft coronary disease has yet to be proven, available evidence points to abnormal lipid metabolism as part of the complex etiologic machinery driving the process of 'chronic rejection'. Consensus exists within the transplant community that a HMG-CoA reductase inhibitor such as pravastatin, should be part of the routine post-transplant drug regimen, and persistent hyperlipidemia should be aggressively treated.

Atorvastatin: an updated review of its pharmacological properties and use in dyslipidaemia

Atorvastatin is a synthetic hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. In dosages of 10 to 80 mg/day, atorvastatin reduces levels of total cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride and very low-density lipoprotein (VLDL)-cholesterol and increases high-density lipoprotein (HDL)-cholesterol in patients with a wide variety of dyslipidaemias. In large long-term trials in patients with primary hypercholesterolaemia. atorvastatin produced greater reductions in total cholesterol. LDL-cholesterol and triglyceride levels than other HMG-CoA reductase inhibitors. In patients with coronary heart disease (CHD), atorvastatin was more efficacious than lovastatin, pravastatin. fluvastatin and simvastatin in achieving target LDL-cholesterol levels and, in high doses, produced very low LDL-cholesterol levels. Aggressive reduction of serum LDL-cholesterol to 1.9 mmol/L with atorvastatin 80 mg/day for 16 weeks in patients with acute coronary syndromes significantly reduced the incidence of the combined primary end-point events and the secondary end-point of recurrent ischaemic events requiring rehospitalisation in the large. well-designed MIRACL trial. In the AVERT trial, aggressive lipid-lowering therapy with atorvastatin 80 mg/ day for 18 months was at least as effective as coronary angioplasty and usual care in reducing the incidence of ischaemic events in low-risk patients with stable CHD. Long-term studies are currently investigating the effects of atorvastatin on serious cardiac events and mortality in patients with CHD. Pharmacoeconomic studies have shown lipid-lowering with atorvastatin to be cost effective in patients with CHD, men with at least one risk factor for CHD and women with multiple risk factors for CHD. In available studies atorvastatin was more cost effective than most other HMG-CoA reductase inhibitors in achieving target LDL-cholesterol levels. Atorvastatin is well tolerated and adverse events are usually mild and transient. The tolerability profile of atorvastatin is similar to that of other available HMG-CoA reductase inhibitors and to placebo. Elevations of liver transaminases and creatine phosphokinase are infrequent. There have been rare case reports of rhabdomyolysis occurring with concomitant use of atorvastatin and other drugs.

CONCLUSION

Atorvastatin is an appropriate first-line lipid-lowering therapy in numerous groups of patients at low to high risk of CHD. Additionally it has a definite role in treating patients requiring greater decreases in LDL-cholesterol levels. Long-term studies are under way to determine whether achieving very low LDL-cholesterol levels with atorvastatin is likely to show additional benefits on morbidity and mortality in patients with CHD.