Statins for improving renal outcomes: a meta-analysis

Renal function and effect of statin therapy on cardiovascular outcomes in patients undergoing coronary revascularization (from the CREDO-Kyoto PCI/CABG Registry Cohort-2)

Although statin therapy is essential for secondary cardiovascular prevention, the therapeutic effect of statins on cardiovascular outcomes in patients with advanced chronic kidney disease (CKD) after coronary revascularization has not been fully elucidated. In the CREDO-Kyoto Registry Cohort-2, 14,706 patients who underwent first coronary revascularization were divided into 4 strata based on estimated glomerular filtration rate (eGFR) or status of hemodialysis (HD). Patients in each stratum were further divided into 2 groups based on statin therapy at discharge: non-CKD stratum (eGFR ≥60 ml/min/1.73 m(2)), 8,959 patients (statin, n = 4,747; no statin, n = 4,212); mild CKD stratum (eGFR ≥30 to <60 ml/min/1.73 m(2)), 4,567 patients (statin, n = 2,135; no statin, n = 2,432); severe CKD stratum (eGFR <30 ml/min/1.73 m(2)), 608 patients (statin, n = 229; no statin, n = 379); and HD stratum, 572 patients (statin, n = 117; no statin, n = 455). Median follow-up duration was 956 days (interquartile range 699 to 1,245). Adjusted risk for major adverse cardiovascular events (MACEs; composite of cardiovascular death, myocardial infarction, or stoke) was significantly lower in the statin group than in the no-statin group in the non-CKD (hazard ratio 0.8, 95% confidence interval 0.68 to 0.95, p = 0.01) and mild CKD (hazard ratio 0.69, 95% confidence interval 0.56 to 0.84, p = 0.0002) strata. However, a significant association of statin therapy and lower risk for MACEs was not seen in the severe CKD (hazard ratio 0.91, 95% confidence interval 0.6 to 1.38, p = 0.65) and HD (hazard ratio 1.04, 95% confidence interval 0.64 to 1.69, p = 0.87) strata. In conclusion, statin therapy was associated with significantly lower risk for MACEs in patients with non-CKD and mild CKD undergoing coronary revascularization. However, therapeutic benefits of statins were not apparent in patients with severe CKD and HD.

Effects of adding ezetimibe to fluvastatin on kidney function in patients with hypercholesterolemia: a randomized control trial

AIMS

Statins not only reduce low-density lipoprotein (LDL) cholesterol, but also prevent the progression of kidney dysfunction. Ezetimibe, a cholesterol-absorption inhibitor, also lowers LDL cholesterol levels when added to statins; however, the effect of add-on ezetimibe on kidney function has had conflicting results.

METHODS

We conducted an open-labeled, randomized, 12-month trial, comparing the effects of daily therapy with 20 mg fluvastatin either with or without 10 mg ezetimibe in 54 patients with dyslipidemia. The prespecified primary outcome was the percent change from baseline in kidney function, which was defined by the estimated glomerular filtration rate. The secondary outcomes were the changes in surrogate atherosclerotic markers. All analyses were by intention to treat.

RESULTS

The primary outcome, the percent change from baseline (±SE) of the estimated glomerular filtration rate, was -5.5±1.9% in the fluvastatin-only group and 6.6±1.9% in the fluvastatin-plus-ezetimibe (combined-therapy) group (p=0.0002). Secondary outcomes, consisting of the cardioankle vascular index, augmentation index, ankle-brachial index, and maximum intima-media thickness of the carotid arteries, did not differ significantly between the two groups. At the end of the study, the mean (±SD) LDL cholesterol was 122±23 mg per deciliter in the fluvastatin group and 111±29 mg per deciliter in the combined-therapy group (a between-group difference of 9.2%, p= 0.036). Side-effect and safety profiles were similar in the two groups.

CONCLUSION

Combined therapy with fluvastatin 20 mg plus ezetimibe 10 mg daily resulted in a significant improvement in changes in the estimated glomerular filtration rate.

Mechanisms and treatment of CKD

As CKD continues to increase worldwide, along with the demand for related life-saving therapies, the financial burden of CKD will place an increasing drain on health care systems. Experimental studies showed that glomerular capillary hypertension and impaired sieving function with consequent protein overload play a pathogenic role in the progression of CKD. Consistently, human studies show that proteinuria is an independent predictor of progression and that its reduction is renoprotective. At comparable BP control, inhibitors of the renin-angiotensin system (RAS), including angiotensin converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs), more effectively than non-RAS inhibitor therapy reduce proteinuria, slow progression to ESRD, and even improve the kidney function achieving disease regression in some cases. In participants with diabetes, RAS inhibitors delay the onset of microalbuminuria and its progression to macroalbuminuria, and ACE inhibitors may reduce the excess cardiovascular mortality associated with diabetic renal disease. In addition to RAS inhibitors, however, multimodal approaches including lifestyle modifications and multidrug therapy will be required in most cases to optimize control of the several risk factors for CKD and related cardiovascular morbidity. Whether novel medications may help further improve the cost-effectiveness of renoprotective interventions is a matter of investigation.

Statins for renal patients: a fiddler on the roof?

Atherosclerotic cardiovascular disease is the main cause of morbidity and mortality in chronic kidney disease patients. There is a raft of evidence showing that in the general population dyslipidaemia is associated with an increased risk of cardiovascular events, as well as with a greater prevalence of chronic kidney disease. Consequently, the use of statins in the general population with dyslipidaemia is not controversial. Nevertheless, the benefits of statins in patients with chronic kidney disease are more elusive. The authors review the possible effects of statins on the progression of renal disease and cardiovascular events in chronic kidney disease patients.

Factors associated with chronic kidney disease progression in Australian nephrology practices

BACKGROUND/AIMS

Chronic kidney disease (CKD) is a major health issue worldwide. The aim of this study was to explore factors associated with CKD progression in Australian nephrology practices.

METHODS

This was a retrospective study utilising an electronic medical record (EMR), Audit4 (Software for Specialists, Australia). The baseline visit was defined as the first entry into the EMR. The primary outcome was the rate of change in estimated glomerular filtration rate (eGFR).

RESULTS

1,328 patients were included with a mean eGFR at baseline of 37.4 ± 0.7 ml/min/1.73 m(2), a mean follow-up of 17.7 months and a mean annual rate of change in eGFR of -0.84 ± 0.26 ml/min/1.73 m(2). Univariate analysis demonstrated that women, smokers, and patients prescribed erythropoiesis-stimulating agents (ESA) had a significantly more rapid decline in eGFR (p = 0.007, 0.033, and 0.003, respectively). On multivariate analysis: gender, age, prescription of ESA and phosphate binders, and baseline eGFR were significantly associated with CKD progression (p = 0.003, 0.004, <0.001, 0.029, and <0.001, respectively).

CONCLUSIONS

This study identifies potential factors associated with CKD progression in a population referred to nephrologists, but current data quality may result in bias. Implementation of changes in the format of data collection is required so that busy clinicians record essential information to enable this to become a more accurate and reliable research tool.

Effects of atorvastatin on renal function in patients with dyslipidemia and chronic kidney disease: rationale and design of the ASsessment of clinical Usefulness in CKD patients with Atorvastatin (ASUCA) trial

BACKGROUND

Since dyslipidemia has been shown to be an independent risk factor for the progression of chronic kidney disease (CKD), low-density lipoprotein cholesterol (LDL-C)-lowering therapy can be potentially associated with inhibition of CKD progression. The ASsessment of clinical Usefulness in CKD patients with Atorvastatin (ASUCA) trial was designed to determine whether atorvastatin has protective effects on renal function in patients with dyslipidemia and CKD.

METHODS

We decided to carry out a prospective multi-center, open-labeled, randomized trial to compare the reno-protective effects between diet therapy alone and atorvastatin plus diet therapy in patients with dyslipidemia (LDL-C ≥ 140 mg/dL if not treated or LDL-C ≥ 100 mg/dL if treated with lipid-lowering drugs in subjects taking dyslipidemia-treating agents other than statins) and CKD [estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m(2)]. The primary endpoint is the change in eGFR (mL/min/1.73 m(2)) as calculated by the modified MDRD equation for Japanese after 2 years of treatment.

RESULTS

Enrollment began in April 2009 and was completed in March 2011. A total of 334 patients (213 male and 121 female) were randomly assigned to either diet therapy alone or atorvastatin plus diet therapy and included in an intent-to-treat population. In the atorvastatin and control groups, the mean ages were 63.2 and 63.1 years, mean eGFRs were 55.9 and 54.0 mL/min/1.73 m(2), and median urinary albumin/creatinine ratios were 24.9 and 29.1 mg/g, respectively.

CONCLUSIONS

This study distinguishes itself from similar studies by increasing statistical accuracy derived from its significantly larger sample size and longitudinal magnitude. The results of this study will help to determine whether atorvastatin has reno-protective effects in patients with dyslipidemia and CKD.

Can existing drugs approved for other indications retard renal function decline in patients with type 1 diabetes and nephropathy?

Mounting evidence from human, animal, and in vitro studies indicates that existing drugs, developed to treat other disorders, also might be effective in preventing or slowing the progression of diabetic nephropathy to end-stage renal disease. Examples of such drugs include the urate-lowering agent allopurinol, the anti-tumor necrosis factor agents etanercept and infliximab, and the immunomodulating drug abatacept. Because some of these medications are already on the market and have been used for a number of years for other indications, they can be tested immediately in human beings for a beneficial effect on renal function in diabetes. Special emphasis should be placed on evaluating the use of these drugs early in the course of diabetic nephropathy when renal damage is most likely to be reversible and interventions can yield the greatest delay to end-stage renal disease.

Anti-fibrosis therapy and diabetic nephropathy

Diabetes mellitus is rapidly becoming a global health issue that may overtake cancer during the next two decades as it covertly affects multiple organ systems that goes undiagnosed long after the onset. A number of complications are associated with poorly controlled hyperglycemia. Diabetic nephropathy is one of the most common complications of diabetes mellitus. Other than angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blocker (ARB) there is not much in the armamentarium with which to treat patients with overt diabetic nephropathy. Research points towards a multifactorial etiology and complex interplay of several pathogenic pathways that can contribute to the declining kidney function in diabetes. Patients with diabetic nephropathy (and with any chronic kidney disease) eventually develop kidney fibrosis. Despite the financial and labor investment spent on determining the basic mechanism of fibrosis, not much progress has been made in terms of therapeutic targets available to us today. This may be in part due to paucity in the experimental animal models available. However, there now seems to be a concerted effort from several pharmaceutical companies to develop a drug that would halt/delay the process of fibrosis, if not reverse it. This review discusses the current state of research in the field while staying within the context of diabetic nephropathy.

Statins and kidney disease: is the study of heart and renal protection at the cutting edge of evidence?

PURPOSE OF REVIEW

Dyslipidaemias are noted in all stages of chronic kidney disease (CKD). Currently most evidence for their treatment comes from secondary retrospective analyses of patient subgroups with CKD recruited into clinical trials powered of hypertensive and dyslipideamic cohorts powered for cardiovascular endpoints.These analyses suggest a number of different beneficial effects of statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) on renal, cardiovascular and mortality outcomes. However, there is disagreement on the impact of interventions at different CKD stages, and on treatment targets.

RECENT FINDINGS

The Study of Heart and Renal Protection (SHARP) trial published in June 2011 was the first trial specifically powered to investigate atherosclerotic outcomes in CKD patients. It found a 17% overall reduction in major adverse cardiac events in the statin-treated group compared with placebo, yet no effect on any renal outcomes of proteinuria and progressive decline of glomerular filtration rate. Furthermore, the Swedish Web-system for Enhancement and Development of Evidencebased care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART) investigators provided further important observational data on the beneficial effect of statins in CKD stages I-IV.

SUMMARY

The evidence that statins have a cardiovascular and mortality benefit in CKD stages I-IV has been reinforced by SHARP, which also definitively shows that there are no special safety concerns for their administration in CKD. However, the utility of the use of statins in patients on dialysis is far from clear, at least in our opinion. The effect of statins on renal outcomes is unconvincing and the evidence does not presently support their use for these indications alone.