Blood pressure reduction with HMG-CoA reductase inhibitors in renal transplant recipients

The Entry and Egress of Monocytes in Atherosclerosis: A Biochemical and Biomechanical Driven Process

In accordance with “the response to injury” theory, the entry of monocytes into the intima guided by inflammation signals, taking up cholesterol and transforming into foam cells, and egress from plaques determines the progression of atherosclerosis. Multiple cytokines and receptors have been reported to be involved in monocyte recruitment such as CCL2/CCR2, CCL5/CCR5, and CX3CL1/CX3CR1, and the egress of macrophages from the plaque like CCR7/CCL19/CCL21. Interestingly, some neural guidance molecules such as Netrin-1 and Semaphorin 3E have been demonstrated to show an inhibitory effect on monocyte migration. During the processes of monocytes recruitment and migration, factors affecting the biomechanical properties (e.g., the membrane fluidity, the deformability, and stiffness) of the monocytes, like cholesterol, amyloid-β peptide (Aβ), and lipopolysaccharides (LPS), as well as the biomechanical environment that the monocytes are exposed, like the extracellular matrix stiffness, mechanical stretch, blood flow, and hypertension, were discussed in the latter section. Till now, several small interfering RNAs (siRNAs), monoclonal antibodies, and antagonists for CCR2 have been designed and shown promising efficiency on atherosclerosis therapy. Seeking more possible biochemical factors that are chemotactic or can affect the biomechanical properties of monocytes, and uncovering the underlying mechanism, will be helpful in future studies.

Managing cardiovascular disease risk in South Asian kidney transplant recipients

South Asians (SA) are at higher cardiovascular risk than other ethnic groups, and SA kidney transplant recipients (SA KTR) are no exception. SA KTR experience increased major adverse cardiovascular events both early and late post-transplantation. Cardiovascular risk management should therefore begin well before transplantation. SA candidates may require aggressive screening for pre-transplant cardiovascular disease (CVD) due to their ethnicity and comorbidities. Recording SA ethnicity during the pre-transplant evaluation may enable programs to better assess cardiovascular risk, thus allowing for earlier targeted peri- and post-transplant intervention to improve cardiovascular outcomes. Diabetes remains the most prominent post-transplant cardiovascular risk factor in SA KTR. Diabetes also clusters with other metabolic syndrome components including lower high-density lipoprotein cholesterol, higher triglycerides, hypertension, and central obesity in this population. Dyslipidemia, metabolic syndrome, and obesity are all significant CVD risk factors in SA KTR, and contribute to increased insulin resistance. Novel biomarkers such as adiponectin, apolipoprotein B, and lipoprotein (a) may be especially important to study in SA KTR. Focused interventions to improve health behaviors involving diet and exercise may especially benefit SA KTR. However, there are few interventional clinical trials specific to the SA population, and none are specific to SA KTR. In all cases, understanding the nuances of managing SA KTR as a distinct post-transplant group, while still screening for and managing each CVD risk factor individually in all patients may help improve the long-term success of all kidney transplant programs catering to multi-ethnic populations.

The antihypertensive actions of statins: modulation by salt intake

Hydroxy methyl glutaryl CoA inhibitors (statins) are the agents most frequently used to reduce elevated serum cholesterol. In addition to their cholesterol lowering effects, statins also have nonlipid lowering pleiotropic properties. These include reducing oxidative stress, renin-angiotensin and endothelin synthesis and activity, and improving nitric oxide (NO) synthesis and availability. Thus, one would predict that statins might be able to exert an antihypertensive effect. Experimental models bear out the blood pressure lowering effects but the data from clinical trials have been inconsistent perhaps due to inappropriate experimental designs, sample size, blood pressure measurement techniques etc. Moreover, although experimental models strongly suggest a role for salt intake in the potential antihypertensive responses to statins, available clinical trials fail to report salt intake in the studied populations. The statins' antihypertensive effects remain an unsettled hypothesis and calls for a large clinical trial at a wide range of doses and a controlled salt intake. Statins meanwhile remain as a excellent option to control high cholesterol and in tissue injury prevention.

Add-on-Statin Extended Release Nicotinic Acid/Laropiprant but Not the Switch to High-Dose Rosuvastatin Lowers Blood Pressure: An Open-Label Randomized Study

Introduction. Nicotinic acid (NA) and statins have been associated with reductions in blood pressure (BP). Patients and Methods. We recruited 68 normotensive and hypertensive dyslipidemic patients who were treated with a conventional statin dose and had not achieved lipid targets. Patients were randomized to switch to high-dose rosuvastatin (40 mg/day) or to add-on current statin treatment with extended release (ER) NA/laropiprant (1000/20 mg/day for the first 4 weeks followed by 2000/40 mg/day for the next 8 weeks) for 3 months. Results. Switching to rosuvastatin 40 mg/day was not associated with significant BP alterations. In contrast, the addition of ER-NA/laropiprant to current statin treatment resulted in a 7% reduction of systolic BP (from 134 ± 12 to 125 ± 10 mmHg, P < .001 versus baseline and P = .01 versus rosuvastatin group) and a 5% reduction of diastolic BP (from 81 ± 9 to 77 ± 6 mmHg, P = .009 versus baseline and P = .01 versus rosuvastatin group). These reductions were significant only in the subgroup of hypertensives and were independent of the hypolipidemic effects of ER-NA/laropiprant. Conclusions. Contrary to the switch to high-dose rosuvastatin, the addition of ER-NA/laropiprant to statin treatment was associated with significant reductions in both systolic and diastolic BP.

Current role of statins in the treatment of essential hypertension

IMPORTANCE OF THE FIELD

Hypertension and hyperlipidemia often co-exist and seem to be interrelated through common pathophysiological pathways. Drugs employing beneficial effects in both conditions could be advantageous in a concerted effective management of patients at high cardiovascular risk. Statins are known to enhance cardiovascular protection beyond their lipid-lowering capacity.

AREAS COVERED IN THIS REVIEW

MEDLINE was searched, up to January 2010, for studies assessing the effect of statin treatment on blood pressure control in various populations or animal models of hypertension. The potential mechanisms implicated in the putative antihypertensive action of statins are also reviewed.

WHAT THE READER WILL GAIN

To learn about the role of statins as potential antihypertensive drugs in various populations. Clinical advice for the use of statins either as monotherapy or in combination with antihypertensive drugs in high-risk populations is also provided.

TAKE HOME MESSAGE

Statins may exert a mild, but clinically relevant, antihypertensive effect which is probably mediated by mechanisms that are independent of their lipid-lowering effects. Patients with high BP levels at baseline as well as those treated with ACE inhibitors and calcium channel blockers are expected to benefit more in this regard.

Statins, antihypertensive treatment, and blood pressure control in clinic and over 24 hours: evidence from PHYLLIS randomised double blind trial

OBJECTIVE

To investigate the possibility that statins reduce blood pressure as well as cholesterol concentrations through clinic and 24 hour ambulatory blood pressure monitoring.

DESIGN

Randomised placebo controlled double blind trial.

SETTING

13 hospitals in Italy

PARTICIPANTS

508 patients with mild hypertension and hypercholesterolaemia, aged 45 to 70 years.

INTERVENTION

Participants were randomised to antihypertensive treatment (hydrochlorothiazide 25 mg once daily or fosinopril 20 mg once daily) with or without the addition of a statin (pravastatin 40 mg once daily). Main outcome measures Clinic and ambulatory blood pressure measured every year throughout an average 2.6 year treatment period.

RESULTS

Both the group receiving antihypertensive treatment without pravastatin (n=254) (with little change in total cholesterol) and the group receiving antihypertensive treatment with pravastatin (n=253) (with marked and sustained reduction in total cholesterol and low density lipoprotein cholesterol) had a clear cut sustained reduction in clinic measured systolic and diastolic blood pressure as well as in 24 hour, and day and night, systolic and diastolic blood pressure. Pravastatin performed slightly worse than placebo, and between group differences did not exceed 1.9 (95% confidence interval -0.6 to 4.3, P=0.13) mm Hg throughout the treatment period. This was also the case when participants who remained on monotherapy with hydrochlorothiazide or fosinopril throughout the study were considered separately.

CONCLUSIONS

Administration of a statin in hypertensive patients in whom blood pressure is effectively reduced by concomitant antihypertensive treatment does not have an additional blood pressure lowering effect. Trial registration BRISQUI_*IV_2004_001 (registered at Osservatorio Nazionale sulla Sperimentazione Clinica dei Medicinali-National Monitoring Centre on Clinical Research with Medicines).

Hypertension in dialysis and kidney transplant patients

For the first time, the Canadian Hypertension Education Program has studied the evidence supporting blood pressure control in people requiring renal replacement therapy for end-stage kidney disease, including those on dialysis and with renal transplants. According to the Canadian Organ Replacement Registry's 2008 annual report, there were an estimated 33,832 people with end-stage renal disease in Canada at the end of 2006, an increase of 69.7% since 1997. Of these, 20,465 were on dialysis and 13,367 were living with a functioning kidney transplant. Thus, it is becoming more likely that primary care practitioners will be helping to care for these complex patients. With the lack of large controlled clinical trials, the consensus recommendation based on interpretation of the existing literature is that blood pressure should be lowered to below 140/90 mmHg in hypertensive patients on renal replacement therapy and to below 130/80 mmHg for renal transplant patients with diabetes or chronic kidney disease.

Impact of immunosuppressive medication on the risk of renal allograft failure due to recurrent glomerulonephritis

Recurrent glomerulonephritis is a major problem in kidney transplantation but the role of immunosuppression in preventing this complication is not known. We used data from the United States Renal Data System to examine the effect of immunosuppressive medication on allograft failure due to recurrent glomerulonephritis for 41,272 patients undergoing kidney transplantation from 1990 to 2003. Ten-year incidence of graft loss due to recurrent glomerulonephritis was 2.6% (95% confidence interval [CI]: 2.3-2.8%). After adjusting for important covariates, the use of cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, sirolimus or prednisone was not associated with graft failure due to recurrent glomerulonephritis. There was no difference between cyclosporine and tacrolimus or between azathioprine and mycophenolate mofetil in the risk of graft failure due to recurrent glomerulonephritis. However, any change in immunosuppression during follow-up was independently associated with graft loss due to recurrence (adjusted hazard ratio 1.30, 95% CI: 1.06-1.58, p = 0.01). In patients with a pretransplant diagnosis of glomerulonephritis, the risk of graft loss due to recurrence was not associated with any specific immunosuppressive medication. The selection of immunosuppression for kidney transplant recipients should not be made with the goal of reducing graft failure due to recurrent glomerulonephritis.

Late effects of chronic graft-versus-host disease

Hematopoietic-cell transplantation (HCT) has become applicable to a broader range of ages and underlying diagnoses through advances in the utilization of alternative donors and stem-cell sources, reduced-intensity preparative regimens, and improved supportive care. The reduction in early transplant-related mortality means that more survivors will potentially develop chronic graft-versus-host disease (cGVHD) and associated late effects. Recipients of HCT are at risk for late end-organ dysfunction as a complication of chemoradiotherapy given before HCT, but disturbances are often multifactorial. This review focuses on problems arising predominantly as a result of cGVHD and its therapies. Disabilities caused by severe or inadequately treated cGVHD include keratoconjunctivitis sicca, bronchiolitis obliterans, skin ulcers, joint contractures, esophageal and vaginal stenosis, osteoporosis, avascular necrosis, and others. Almost all organ systems may be involved, and a broad approach is needed to allow recognition and anticipation of problems so that prevention or early intervention is possible.

Reduction in blood pressure with statins: results from the UCSD Statin Study, a randomized trial

BACKGROUND

Some studies have suggested reductions in blood pressure (BP)with statin treatment, particularly in persons with hypertension. Randomized trial evidence is limited.

METHODS

We performed a randomized, double-blind, placebo-controlled trial with equal allocation to simvastatin, 20 mg; pravastatin sodium,40 mg; or placebo for 6 months. Nine hundred seventy-three men and women without known cardiovascular disease or diabetes mellitus, with low-density lipoprotein cholesterol screening levels of 115 to 190 mg/dL, had assessment of systolic and diastolic BP (SBP and DBP, respectively). Blood pressure values were compared for placebo vs statins by intention-to-treat (ITT) analysis. Additional analyses were performed that (1) were confined to subjects with neither high baseline BP (SBP>140 mm Hg or DBP>90 mm Hg) nor receiving BP medications, to exclude groups in whom BP medications or medication changes may have influenced results, and (2) separately evaluated simvastatin and pravastatin (vs placebo). The time course of BP changes after statin initiation and the effect of stopping statins on BP were examined.

RESULTS

Statins modestly but significantly reduced BP relative to placebo,by 2.2 mm Hg for SBP (P=.02) and 2.4 mm Hg for DBP (P<.001) in ITT analysis. Blood pressure reductions ranged from 2.4 to 2.8 mm Hg for both SBP and DBP with both simvastatin and pravastatin, in those subjects with full follow-up, and without potential for influence by BP medications (ie, neither receiving nor meriting BP medications).

CONCLUSIONS

Reductions in SBP and DBP occurred with hydrophilic and lipophilic statins and extended to normotensive subjects. These modest effects may contribute to the reduced risk of stroke and cardiovascular events reported on statins. Trial Registration clinicaltrials.gov Identifier: NCT00330980.

Beyond lipid lowering: the anti-hypertensive role of statins

INTRODUCTION

The management of the hypercholesterolemic patient has evolved tremendously with the introduction of the HMG-CoA Reductase inhibitors, a class of drugs better known as the statins. Statins modify cholesterol metabolism by inhibiting the rate-limiting enzyme of cholesterol biosynthesis, producing greater decreases in plasma cholesterol levels than previously realized with hypolipidemic therapy. With the advent of the classic statin-megatrials such as the Scandinavian Simvastatin Survival Study (4S), WOSCOPS, CARE, and the more recent Heart Protection Study (HPS), the role of statins in both the primary and secondary prevention and ultimate risk reduction of patients with coronary disease has been firmly established.

DISCUSSION

With an increase in use and popularity, a number of beneficial actions of the statins unrelated to their cholesterol-lowering ability have been reported. These effects have generated greater interest in the possible additional roles and indications for the use of these drugs. Of central focus in this paper is the cholesterol-independent benefit of this group of agents on the cardiovascular system, particularly on the lowering of systemic blood pressure. A number of hypotheses have been proposed for this action and these shall be reviewed within this paper.

CONCLUSION

We explore recent data that suggests that statins may provide substantial reduction of blood pressure in the hypertensive, hypercholesterolemic patient independent of their lipid-lowering effect. In addition, we review several notable publications that postulate unique mechanisms for this action and benefit. We also present plausible explanations as to why some of the larger statin trials did not report similar such findings.

Analysis of antihypertensive effects of statins

Hypertension and hyperlipidemia, two powerful risk factors of cardiovascular disease (CVD), often coexist. Therefore, treatment should consider the beneficial properties of drugs used to treat either condition. Statins, the mainstay of lipid-lowering therapy, result in a significant clinical benefit both in primary and secondary CVD prevention. In addition to their hypolipidemic capacity, other properties may contribute to statin-induced benefits. Clinical and experimental evidence indicates that statins may modulate blood pressure (BP). The mechanisms by which statins reduce BP seem to be largely independent of their lipid effects. Although small, reductions in BP are possibly clinically relevant. Large landmark studies confirm that statins can reduce CVD risk in hypertensive patients. These findings suggest that statins could be prescribed as an adjunct in treating hypertension with dyslipidemia or even in patients with "normal" cholesterol levels. Whether the effect of statins on BP is accompanied by an additional decrease in clinical outcomes needs to be investigated in long-term, large-scale trials.

Statins: another class of antihypertensive agents?

The assessment of global cardiovascular risk is an essential step in the management of atherosclerotic disease prevention. Among the risk factors to be addressed are hypertension and hyperlipidaemia; these commonly coexist. A neutral or lipid-friendly antihypertensive agent is probably useful in the presence of lipid abnormalities. Similarly, statins have been shown to decrease cardiovascular risk in hypertensive patients. There is also experimental and clinical evidence that statins have blood pressure (BP)-lowering effects. In this review, we discuss the beneficial effects of statins on BP, and provide an overview of the underlying pathophysiology. We also consider the evidence justifying the use of statins in the management of hypertensive patients.

Drug Insight: immunomodulatory effects of statins—potential benefits for renal patients?

Statins inhibit 3-hydroxyl-3-methylglutaryl coenzyme A reductase, an enzyme crucial to cholesterol synthesis. Drugs of this class reduce the risk of coronary heart disease and stroke, in large part through lipid modulation. Emerging evidence indicates that statins have additional modes of action. These actions, which encompass modification of endothelial function, plaque stability, thrombus formation and inflammatory pathways, are widely referred to as 'pleiotropic effects'. These pleiotropic effects indicate that the therapeutic potential of statins might extend beyond cholesterol lowering and cardiovascular disease to other inflammatory disorders or conditions such as transplantation, multiple sclerosis, rheumatoid arthritis and chronic kidney disease. Experimental and clinical data provide evidence to support these broader applications of statins; however, more large-scale trials are needed to clarify the therapeutic benefit.

Effect of pravastatin on blood pressure in people with cardiovascular disease

Experimental evidence and several small studies in humans suggest that HMG-CoA (3-hydroxy 3-methylglutaryl coenzyme A) reductase inhibitors (statins) reduce blood pressure, perhaps through effects on endothelial function or by reducing inflammation. We tested the hypothesis that pravastatin would reduce blood pressure at 3 months and the risk of developing new hypertension over a follow-up period of 5 years. This was a post hoc subgroup analysis of a randomized double-blind placebo-controlled trial of pravastatin 40 mg daily vs placebo in 4159 participants with previous myocardial infarction and total plasma cholesterol <240 mg/dl (6.2 mmol/l). The primary outcome was the unadjusted change in mean arterial pressure (MAP) from baseline to 3 months. We also considered systolic and diastolic blood pressure (SBP and DBP) and pulse pressure. Analysis of covariance was used to calculate the adjusted effect of treatment on change in these outcomes at 3, 6, 12 and 24 months postrandomization, after controlling for potential confounders. Logistic regression was used to calculate the adjusted effect of treatment on incident hypertension (blood pressure > or =140/90 in those without known hypertension at baseline). This analysis included 4126/4159 (99.2%) participants for whom blood pressure was measured at baseline and during at least one follow-up visit. Median duration of follow-up was 57.8 months. The unadjusted and adjusted change in MAP, SBP, DBP or pulse pressure from baseline was not significantly different for pravastatin or placebo recipients at 3, 6, 12 or 24 months after randomization, or at last follow-up. Pravastatin did not reduce the adjusted risk of incident systolic hypertension (odds ratio 0.99, 95% CI 0.80-1.23), or incident diastolic hypertension (odds ratio 0.97, 95% CI 0.73-1.27). In summary, pravastatin 40 mg daily did not reduce blood pressure in survivors of myocardial infarction without overt hypercholesterolaemia.

A prospective evaluation of the effect of simvastatin on heart rate variability in non-ischemic cardiomyopathy

BACKGROUND

Modulation of sympathetic tone may contribute to statin-mediated reduction in sudden cardiac death. We examined the effect of simvastatin on heart rate variability (HRV) in patients with non-ischemic dilated cardiomyopathy to evaluate for an antisympathetic effect of statins independent of anti-ischemic properties.

METHODS

The study was a prospective, open-label, self-controlled trial. Frequency domain analysis of HRV was assessed in 25 patients with non-ischemic dilated cardiomyopathy at baseline and after a 6-week course of simvastatin. The primary end point was the change in 5-minute sitting total spectral power (TSP) as a composite measurement of autonomic nervous system modulation. Secondary end points included the change in respiratory frequency area (RFa) with deep breathing (parasympathetic stress) and in low-frequency area (LFa) with Valsalva (sympathetic stress).

RESULTS

Simvastatin had no effect on 5-minute sitting TSP (baseline 1932 +/- 1165 vs posttreatment 2570 +/- 1877 square milliseconds, P = .770), RFa with deep breathing (baseline 19 +/- 7 vs posttreatment 14 +/- 4 [beat/min]2, P = .31), or LFa with Valsalva (baseline 26 +/- 6 vs posttreatment 32 +/- 8 [beat/min]2, P = .342). Bivariate analysis demonstrated no correlation between low-density lipoprotein (LDL) change and change in TSP or RFa, but did demonstrate an inverse relationship between change in LDL and change in LFa with Valsalva stress (r = -0.45 and P = .041).

CONCLUSION

Although simvastatin did not change baseline HRV, a modest relationship exists between the extent of LDL reduction and sympathetic responsiveness to stress.

Impact of statin treatment on 1-year functional and histologic renal allograft outcome

BACKGROUND

Statins are antilipidemic agents that exhibit a variety of cellular effects independent of their lipid-lowering action. A retrospective study was undertaken to establish the impact of statins on graft outcome in the first year posttransplantation.

METHODS

Data from patients with uniform immunosuppression (cyclosporine, mycophenolate mofetil, and prednisolone) who underwent transplantation at the authors' unit from 1997 to 2002 were reviewed. Patients prescribed statins were compared with those not on a statin. Mean change in creatinine clearance (CrCl) from 3 to 12 months posttransplantation was calculated. Histomorphometric analysis was used to quantify fractional interstitial area and collagen III deposition in matched preperfusion and 12-month protocol biopsy specimens.

RESULTS

Seventy-seven patients met study criteria: statin, n=44 patients; nonstatin, n=33 patients. Median time to commencing a statin was 5 weeks. At 3 months, CrCl (+/-SEM) was similar: 51.6+/-2.9 mL/min (statin) versus 51.3+/-1 mL/min (nonstatin). At 12 months, the mean change in CrCl was 4.1+/-1 mL/min (statin) compared with -2.0+/-1.8 mL/min (nonstatin), resulting in a difference of 6.13 mL/min at 12 months (P<0.005). Mean preperfusion fractional interstitial areas were similar (23.9+/-1.6%; P=not significant [NS]). On 12-month biopsy specimens, the fractional interstitial area had increased to 34+/-3.2% in the nonstatin group (P<0.005), with no change in the statin group. Interstitial collagen III deposition was similar in preperfusion biopsy specimens (10.4+/-1%; P=NS), but at 12 months it was significantly greater in the nonstatin group (17.6+/-1%; P<0.05)

CONCLUSIONS

Early introduction of statins may be associated with improved 1-year graft outcome.

The statins--therapeutic diversity in renal disease?

PURPOSE OF REVIEW

Statins significantly reduce cholesterol synthesis and reduce cardiovascular morbidity and mortality. In addition, they appear to have beneficial effects independent of their ability to lower cholesterol. Recent publications suggesting a potential role for statin therapy in chronic renal insufficiency, hypertension and following organ transplantation are reviewed.

RECENT FINDINGS

Pharmacokinetic studies have shown statins to be well-tolerated and effective in patients on long-term haemodialysis, providing equivalent control of lipid levels to that seen in matched controls. Preliminary clinical trials suggest that statins may have beneficial disease-modifying effects in chronic inflammatory disease. Furthermore, immunosuppressive and immunomodulatory actions may confer benefit following cardiac transplantation, but this remains to be demonstrated definitively in renal transplant patients. Data to date suggest that, in addition to reduction of cardiovascular risk, statins may help slow the progress of chronic renal insufficiency, particularly in patients with proteinuria. Addition of statin therapy may also contribute to the control of systemic and pulmonary hypertension.

SUMMARY

Encouraging data in support of a wider spectrum of use for statins are emerging. In addition to reduction of cardiovascular risk through lipid lowering, they may represent an important adjunctive therapy in patients with chronic kidney diseases and post-transplantation. However, further large, well-designed clinical trials are required before their widespread use can be recommended in this setting.

Therapeutic Considerations for the Use of Statin Therapy in Chronic Renal Disease

This review presents an evidence-based analysis of the use of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) in patients with chronic renal disease. It considers the characteristics and incidence of dyslipidaemia among specific patient types and describes the available data concerning the ability of statin therapy to regulate dyslipidaemia in the renal disease population as well as early results for an anti-inflammatory effect in this group. The clinical impact of statins in terms of reduced morbidity and mortality is also discussed. The relative merits of different statin agents are reviewed in terms of efficacy and safety, together with the role of aggressive intervention as compared with standard approaches to care. Finally, a proposed algorithm for the initiation and monitoring of statin therapy in chronic renal disease patients is presented.

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

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

Does aggressive statin therapy offer improved cholesterol-independent benefits compared to conventional statin treatment?

There is currently intense research interest in the properties of HMG-CoA reductase inhibitors (statins) beyond their well-documented lipid-lowering action. Studies have consistently demonstrated that administration of statin therapy decreases levels of the inflammatory marker C-reactive protein (CRP), a marker associated with an increased risk of cardiovascular events. This effect appears to be independent of the extent of reduction in total or LDL-cholesterol. Statins also appear to improve endothelial dysfunction by increasing endothelium-dependent vasodilatation. There is also evidence that statins inhibit fibrin formation and thrombus development, an effect that which would be clinically beneficial following plaque fissure or rupture. Early preclinical and clinical evidence suggests that there are quantitative differences between statin regimens in terms of their cholesterol-independent properties. Trials comparing equipotent doses of different statins, based on lipid-lowering efficacy, have not reported any differences in cholesterol-independent properties. However, the current evidence base indicates that more aggressive statin regimens are associated with an enhanced anti-inflammatory effect. Intensive lipid-lowering using statin therapy generates a greater reduction in mortality than standard lipid management, and it is possible that enhanced cholesterol-independent effects may account for some of this excess benefit.

The cardioprotective effects of statins

In addition to their lipid-modulating properties, statins have a large number of beneficial cardiovascular effects that have emerged over time and that were not anticipated during drug development. The lipid and nonlipid effects act in a concerted way to reduce the ischemic burden of the myocardium and to protect it against injury. By acting on the vessel wall, statins may prevent lesion initiation and repair injuries, enhance myocardial perfusion, slow lesion progression, and prevent coronary occlusion. They may also directly reduce myocardial damage, favor myocardial repair, and protect against immune injury. This review focuses on properties of statins that contribute to their cardioprotective effect. The first section includes information on modulation of vascular tone, endothelial permeability and function, inhibition of complement injury, curbing of foam cell formation, antioxidant and anti-inflammatory properties, and profibrinolytic and anticoagulant activities. The second section relates to reduction of myocardial necrosis, myocardial hypertrophy, blood pressure, and heart failure, as well as mobilization of endothelial progenitor cells for repair, angiogenic effects, and immunomodulation. In many instances, results of in vitro and animal studies have raised expectations and prompted studies in humans. Several clinical trials have confirmed these expectations and have strengthened the value of statins as valuable antiatherosclerotic and cardioprotective agents.

The lipid and non-lipid effects of statins

The 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors, more commonly known as statins, are a class of drug widely used for the treatment of hypercholesterolaemia in patients with established cardiovascular disease as well as those at high risk of developing atherosclerosis. Their predominant action is to reduce circulating levels of low-density lipoprotein (LDL) cholesterol; to a smaller degree, they also increase high-density lipoprotein (HDL) cholesterol and reduce triglyceride concentrations. In recent years, however, there has been an increasing body of evidence that their effects on lipid profile cannot fully account for their cardiovascular protective actions: their beneficial effects are too rapid to be easily explained by their relatively slow effects on atherogenesis and too large to be accounted for by their relatively small effects on plaque regression. Experimental models have revealed that statins exert a variety of other cardiovascular effects, which would be predicted to be of clinical benefit: they possess anti-inflammatory properties, as evidenced by their ability to reduce the accumulation of inflammatory cells in atherosclerotic plaques; they inhibit vascular smooth muscle cell proliferation, a key event in atherogenesis; they inhibit platelet function, thereby limiting both atherosclerosis and superadded thrombosis; and they improve vascular endothelial function, largely through augmentation of nitric oxide (NO) generation. The relative importance of the lipid- and non-lipid-related effects of the statins in the clinical situation remains the subject of much continuing research.

Early vascular benefits of statin therapy

Large-scale trials established that statin administration in hypercholesterolaemic individuals and patients with coronary heart disease (CHD) significantly reduces the risk of vascular events and death. This benefit was primarily attributed to their actions on lipids. This review focuses on the benefits (clinical and experimental) of statins observed soon (approximately 12 weeks) after their administration. Statins rapidly increase nitric oxide production and improve endothelial function (e.g. increased flow-mediated dilatation). Similarly, antioxidant properties decrease the susceptibility of low density lipoprotein cholesterol to oxidation. Statins inhibit the migration of macrophages and smooth muscle cell proliferation leading to an antiproliferative effect and the stabilisation of atherosclerotic plaques. Anti-inflammatory effects include a reduction in serum C-reactive protein levels, inflammatory and proinflammatory cytokines (e.g. IL-6, IL-8), adhesion molecules (e.g. ICAM-1, VCAM-1) and other acute phase proteins. Statins influence the haemostatic system. They reduce tissue factor expression and platelet activity, whereas fibrinolysis can be enhanced. Statins improve microalbuminuria, renal function, hypertension and arterial wall stiffness. A significant reduction of the carotid intima media thickness (IMT) was also reported early after statin treatment. These early effects of statins probably contribute to the significant reduction in vascular events seen in some 'short-term' studies. There is a need to further elucidate the rapid and non-lipid lowering properties of statins.