Statins for improving renal outcomes: a meta-analysis

Contribution of non-traditional lipid profiles to reduced glomerular filtration rate in H-type hypertension population of rural China

BACKGROUND

Despite current interest in the unfavourable impact of non-traditional lipid profiles on cardiovascular disease, information regarding its relations to reduced glomerular filtration rate (GFR) in H-type hypertension population has not been systemically elucidated.

METHODS

Analyses were based upon a cross-sectional study of 3259 participants with H-type hypertension who underwent assessment of biochemical, anthropometric and blood pressure values. Reduced GFR was considered if meeting estimated GFR <60 ml/min/1.73 m².

RESULTS

A stepwise multivariate regression analysis indicated that non-traditional lipid parameters remained as independent determinants of estimated GFR (all p < .001). In multivariable models, we observed a 50%, 51%, 31%, and 24% higher risk for decreased GFR with each SD increment in TC/HDL-C, TG/HDL-C, LDL-C/HDL-C ratios and non-HDL-C levels, respectively. The highest quartile of TC/HDL-C, TG/HDL-C and LDL-C/HDL-C ratios carried reduced GFR odds (confidence intervals) of 5.50 (2.50 to 12.09), 6.63 (2.58 to 17.05) and 2.22 (1.15 to 4.29), respectively.

CONCLUSIONS

The relative independent contribution of non-traditional lipid profiles, as indexed by TC/HDL-C, TG/HDL-C, LDL-C/HDL-C ratios and non-HDL-C, towards reduced GFR putting research evidence at the very heart of lipoprotein-mediated renal injury set a vital example for applying a clinical and public health recommendation for reducing the burden of chronic kidney disease. KEY MESSAGES Non-traditional lipid profiles has been linked with the occurrence of cardiovascular disease, but none of the studies that address the effect of non-traditional lipid profiles on reduced GFR risk in H-type hypertension population has been specifically established. A greater emphasis of this study resided in the intrinsic value of TC/HDL-C, TG/HDL-C, LDL-C/HDL-C ratios and non-HDL-C that integrate atherogenic and anti-atherogenic lipid molecules to predict the risk of reduced GFR among H-type hypertension population and provide insight into the pathophysiology of subsequent cardio-cerebrovascular outcomes. In a large Chinese H-type hypertension adults, the relative independent contribution of non-traditional lipid profiles, as indexed by TC/HDL-C, TG/HDL-C, LDL-C/HDL-C ratios and non-HDL-C, towards reduced GFR putting research evidence at the very heart of lipoprotein-mediated renal injury set a vital example for applying a clinical and public health recommendation for reducing the burden of CKD.

Adjunctive therapy with statins reduces residual albuminuria/proteinuria and provides further renoprotection by downregulating the angiotensin II-AT1 pathway in hypertensive nephropathy

OBJECTIVES

Blockade of the renin-angiotensin II (Ang II) system by AT1 blockers (ARBs) and angiotensin-converting enzyme inhibitors retards the progression of chronic kidney disease (CKD) by reducing albuminuria/proteinuria. However, many patients with CKD suffer from residual albuminuria/proteinuria, which is an independent risk factor for CKD progression. The aim of the current study is to investigate the effect of pitavastatin, one of the adjunctive agents to ARBs, on the reduction of albuminuria/proteinuria and further renoprotection mediated by telmisartan in spontaneously hypertensive rats.

METHODS AND RESULTS

Forty-two-week-old spontaneously hypertensive rats were grouped randomly and received 8 weeks of treatments with vehicle, telmisartan, pitavastatin or a combination of telmisartan and pitavastatin. Both albuminuria and proteinuria were inhibited significantly in the telmisartan-treated group, but an obviously residual albuminuria was maintained. The combination treatment with telmisartan and pitavastatin displayed a more effective decrease in albuminuria and proteinuria, even to the normal level. Enhanced nephroprotection was also observed in this combination group, which was independent of the cholesterol-lowering effects. Further mechanistic studies revealed that the combination therapy greatly attenuated the expression of intrarenal Ang II and AT1, thereby decreasing the activation of TGF-β-Smad and NF-κB and inhibiting fibrosis and inflammation.

CONCLUSION

Adjunctive therapy with pitavastatin dramatically reduced residual albuminuria/proteinuria and enhanced nephroprotection, likely by downregulating the expression of intrarenal Ang II and AT1. It could be concluded that statins might be a promising adjunctive therapeutic agent to conventional ARB treatment in hypertensive renal damage.

Effects of atorvastatin on proteinuria of type 2 diabetic nephropathy in patients with history of gestational diabetes mellitus: A clinical study

Background

Gestational diabetes is known as one of the diseases through pregnancy. In the present study, changes in proteinuria after atorvastatin administration among patients with history of gestational diabetes were studied.

Materials and Methods

In this randomized clinical trial, 42 patients were included in the study. Atorvastatin was administered for 21 patients, and 21 patients were designated as control group. Lipid profile, protein, and 24 h urine creatinine (uCr) levels were determined in the beginning and 3 months after intervention. P < 0.05 was considered statistically significant.

Results

Lipid profile in intervention group was enhanced; low-density lipoprotein (LDL) had decreased while triglyceride had not changed and high-density lipoprotein had been increased. There was no statistically significant change in serum Cr, serum urea, estimated glomerular filtration rate, uCr, urine volume, 24-h urine protein level, or urine protein/Cr ratio on both groups during the study; also, there was no statistically significant difference between groups.

Conclusions

Although LDL level decreased after atorvastatin therapy, atorvastatin therapy had no effect on the level of proteinuria or other parameters related to kidney function.

Greater low-density lipoprotein cholesterol variability is associated with increased progression to dialysis in patients with chronic kidney disease stage 3

Increasing evidence suggests that lipid variability may be a predictor of cardiovascular events. However, few studies have evaluated the association between lipid variability and renal outcomes in patients with moderate-to-advanced chronic kidney disease (CKD). Therefore, the aims of this study were to assess whether lipid variability is associated with progression to dialysis in patients with CKD stage 3–5, and to evaluate the risk factors of lipid variability. This longitudinal study enrolled 725 patients with CKD stage 3–5. Intra-individual lipid variability was defined as the standard deviations (SDs) of lipid levels. The renal end-point was defined as commencing dialysis. During a mean follow-up period of 3.2 years, 208 patients (28.7%) started dialysis. The patients with CKD stage 3 with high low-density lipoprotein (LDL) cholesterol SD (per 1 mg/dL; hazard ratio, 1.035; 95% confidence interval, 1.003 to 1.067; p = 0.003) were associated with an increased risk of progression to dialysis, however this association was not seen in the patients with CKD stage 4 or 5. Furthermore, in the patients with CKD stage 3, a high urine protein-to-creatinine ratio (p < 0.001) and the use of statins (p < 0.001) were significantly associated with an increased LDL-cholesterol SD. Greater LDL-cholesterol variability was associated with an increased risk of progression to dialysis in patients with CKD stage 3, but not in those with CKD stage 4 or 5. These findings support the potential role of aggressive lipid control on clinical outcomes and highlight its importance in patients with CKD stage 3.

Therapy with atorvastatin versus rosuvastatin reduces urinary podocytes, podocyte-associated molecules, and proximal tubule dysfunction biomarkers in patients with type 2 diabetes mellitus: a pilot study

BACKGROUND

Diabetic nephropathy is a severe complication of Type 2 diabetes. Tubular lesions may play an important role in its early stages. The aim of our study was to determine if atorvastatin protects the podocytes and the proximal tubule in patients with Type 2 diabetes.

METHODS

A total of 63 patients with Type 2 diabetes completed this 6-months prospective pilot study. They were randomized to continue rosuvastatin therapy (control group) or to be administered an equipotent dose of atorvastatin (intervention group), and were assessed regarding urinary podocytes, podocyte-associated molecules, and biomarkers of proximal tubule dysfunction.

RESULTS

The patients from the intervention group presented a significant reduction in podocyturia (from 7.0 to 4.0 cells/ml, p < .05), urinary nephrin (from 1.7 to 1.3 mg/g, p < .001), urinary vascular endothelial growth factor (from 262.8 to 256.9, p < .01), urinary alpha1-microglobulin (from 10.0 to 8.3 mg/g, p < .01), urinary kidney injury molecule-1 (from 139.5 to 136.3 ng/g, p < .001), and urinary advanced glycation end-products (from 112.6 to 101.3 pg/ml, p < .001). Podocyturia correlated directly with the podocyte damage biomarkers, proximal tubule dysfunction biomarkers, albumin to creatinine ratio, and advanced glycation end-products, and inversely with the glomerular filtration rate.

CONCLUSIONS

In patients with Type 2 diabetes, atorvastatin exerts favorable effects on the kidney. There is a correlation between the evolution of the podocytes and of the proximal tubule biomarkers, supporting the hypothesis that the glomerular changes parallel proximal tubule dysfunction in the early stages of diabetic nephropathy.

Long-term changes in albuminuria: underlying causes and future mortality risk in a 20-year prospective cohort: the Nord-Trøndelag Health (HUNT) Study

OBJECTIVE

Knowledge on how changing risk factors influence the progression of albuminuria over time is still limited. Furthermore, large population-based cohorts are needed to study the association between albuminuria change and mortality risk in nondiabetic study participants.

METHODS

We evaluated changes of albuminuria in 6282 nondiabetic individuals from the Norwegian population-based Nord-Trøndelag Health study. Using three albumin/creatinine ratios (ACR), we studied the influence of cardiovascular risk factors on ACR change from baseline to follow-up 11 years later. We evaluated the next 8-year mortality risk by using flexible parametric methods to identify nonlinear main effects and their two-way interactions.

RESULTS

Mean albuminuria increased significantly over 11 years (1.82-3.02 mg/mmol, P < 0.0001), but two-thirds of individuals had stable levels (ΔACR -1.40 to 1.40 mg/mmol). Higher age, ACR, and SBP as well as smoking and lower glomerular filtration rate at baseline were associated with increasing albuminuria. Study participants in the upper quartile of the increasing group had mean adjusted hazard ratio 1.31 (P = 0.004) for all-cause mortality compared with those with stable ACR. Those with decreasing ACR also had increased mortality, but the risk was strongly attenuated when adjusting for comorbidity. It also decreased the first 3 years before increasing. There was a strong interaction between baseline ACR and ΔACR. Increasing albuminuria had strongest effect on mortality in study participants with moderately increased baseline values.

CONCLUSION

Both increasing and decreasing albuminuria are significant independent predictors of mortality in nondiabetic individuals, but must be interpreted in light of baseline values. Cutoffs and clinical usefulness in nondiabetic study participants should be further investigated.

The effect of statins on renal outcomes in patients with diabetic kidney disease: A systematic review and meta-analysis

The effects of statins on renal outcomes in patients with diabetic kidney disease were conflicting. The aim of the study was to investigate whether statins treatment could affect renal outcomes (albuminuria or proteinuria, estimated glomerular filtration rate [eGFR]) for diabetic kidney disease patients. We searched the PubMed, OVID (including MEDLINE and EMBASE), Web of Science and the Cochrane Central Register of Controlled Trials. Randomized controlled trials evaluating the efficacy of statins in diabetic kidney disease patients were selected. The main outcomes were albuminuria (or proteinuria). Secondary outcomes were levels of eGFR. Two authors independently assessed study quality and extracted the information from enrolled trials. Eleven randomized controlled trials with a total number of 543 diabetic kidney disease participants were included in our study. The overall estimates showed that statins statistically reduced albuminuria (standardized mean differences -0.71, 95% CI -1.20 to -0.23, P = .004), though marked heterogeneity was found within studies. However, the analysis results indicated that statins could not reduce overt proteinuria (standardized mean differences -0.14, 95% CI -0.53 to 0.26, P = .49) or slow the rate of reduction in eGFR (standardized mean differences 0.06, 95% CI -0.14 to 0.26, P = .53). In general, our study demonstrated that statins might have beneficial effects on reducing albuminuria in diabetic kidney disease patients. However, there was no strong evidence that the same intervention had an effect on overt proteinuria or eGFR outcomes in these patients.

Variability in Total Cholesterol Is Associated With the Risk of End-Stage Renal Disease: A Nationwide Population-Based Study

OBJECTIVE

Recent data suggest that visit-to-visit variability of cholesterol is associated with cardiovascular events. We evaluated the role of lipid variability as a determinant of end-stage renal disease (ESRD).

APPROACH AND RESULTS

Using nationally representative data from the Korean National Health Insurance System, 8 493 277 subjects who were free of ESRD and who underwent ≥3 health examinations during 2005 to 2010 were followed to the end of 2015. Total cholesterol (TC) variability was measured using the coefficient of variation, SD, and the variability independent of the mean. The primary outcome was the development of ESRD, defined as a combination of the relevant disease code and the initiation of renal replacement therapy. There were 11 247 cases of ESRD during a median follow-up of 6.1 years. There was a graded association between a higher TC variability and incident ESRD. In the multivariable adjusted model, the hazard ratios and 95% confidence intervals comparing the highest versus lowest quartiles of coefficient of variation of TC were 2.66 (95% confidence interval, 2.52-2.82). The results were consistent when the variability of TC was modeled using SD and variability independent of the mean and were independent of preexisting chronic kidney disease.

CONCLUSIONS

Increasing TC variability was associated with an increasing incidence of ESRD.

Successful treatment of a patient with refractory nephrotic syndrome with PCSK9 inhibitors: a case report

Background

The proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor evolocumab is a low-density lipoprotein (LDL)-lowering drug with a new mechanism, which is currently available in Japan. Here, for the first time, we report the successful use of the PCSK9 inhibitor in a patient with refractory nephrotic syndrome.

Case presentation

A 61-year-old woman was diagnosed with minimal change-type nephrotic syndrome in October 2012. She received prednisolone (PSL) and cyclosporin A (CyA), but she experienced several cycles of relapse and remission and was hospitalized in May 2016 due to relapse. However, in spite of steroid pulse therapy and adrenocorticotropic hormone (ACTH) administration, her urinary protein level did not improve. We started her on evolocumab with the expectation of equivalent LDL-lowering effects as seen with LDL apheresis. After that, the LDL cholesterol level and UP/UC were concomitantly decreased, and the serum albumin was increased. This was maintained even when we reduced the PSL dose. This suggests that evolocumab clinically improves the nephrotic condition.

Conclusion

No other report has described the use of evolocumab for nephrotic syndrome (NS) or its effect on similar nephrotic conditions. We believe that the findings presented here are unique and may be beneficial when treating similar cases.

Comparison between Atorvastatin and Rosuvastatin in Renal Function Decline among Patients with Diabetes

BACKGROUND

Although the beneficial effects of statin treatment in dyslipidemia and atherosclerosis have been well studied, there is limited information regarding the renal effects of statins in diabetic nephropathy. We aimed to investigate whether, and which, statins affected renal function in Asian patients with diabetes.

METHODS

We enrolled 484 patients with diabetes who received statin treatment for more than 12 months. We included patients treated with moderate-intensity dose statin treatment (atorvastatin 10 to 20 mg/day or rosuvastatin 5 to 10 mg/day). The primary outcome was a change in estimated glomerular filtration rate (eGFR) during the 12-month statin treatment, and rapid renal decline was defined as a >3% reduction in eGFR in a 1-year period.

RESULTS

In both statin treatment groups, patients showed improved serum lipid levels and significantly reduced eGFRs (from 80.3 to 78.8 mL/min/1.73 m² for atorvastatin [P=0.012], from 79.1 to 76.1 mL/min/1.73 m² for rosuvastatin [P=0.001]). A more rapid eGFR decline was observed in the rosuvastatin group than in the atorvastatin group (48.7% vs. 38.6%, P=0.029). Multiple logistic regression analyses demonstrated more rapid renal function loss in the rosuvastatin group than in the atorvastatin group after adjustment for other confounding factors (odds ratio, 1.60; 95% confidence interval, 1.06 to 2.42).

CONCLUSION

These results suggest that a moderate-intensity dose of atorvastatin has fewer detrimental effects on renal function than that of rosuvastatin.

Effects of atorvastatin on renal function in patients with dyslipidemia and chronic kidney disease: assessment of clinical usefulness in CKD patients with atorvastatin (ASUCA) trial

BACKGROUND

Dyslipidemia is a risk factor for the progression of chronic kidney disease (CKD). While conventional lipid lowering therapy provides a benefit to CKD management, the effect of statins on eGFR remains unclear.

METHODS

A prospective, multi-center, open-labeled, randomized trial. Total of 349 CKD patients with hyperlipidemia were randomized into 2 groups, and followed for 2 years. Group A included patients who were treated with atorvastatin. Group C were treated with conventional lipid lowering drugs other than statin. Primary endpoint was changes in eGFR. Secondary endpoints included changes in urinary albumin excretion, serum LDL-C, serum triglyceride, cardio-vascular events and all-cause mortality.

RESULTS

As the primary endpoint, eGFR decreased by 2.3 ml/min/1.73 m2 in Group A and by 2.6 ml/min/1.73 m2 in Group C, indicating that there was no difference in change of eGFR between the two groups. As secondary endpoints, atorvastatin succeeded to reduce serum LDL-C level significantly and rapidly, but conventional therapy did not. In fact, mean LDL-C level did not reach the target level of 100 mg/dl in Group C. Serum triglyceride was lowered only by atorvastatin, but not conventional drugs. The number of cardiovascular events and all-cause mortality did not differ between in two groups.

CONCLUSION

The ASUCA (Assessment of Clinical Usefulness in CKD Patients with Atorvastatin) trial demonstrated that atorvastatin failed to exhibit reno-protections compared to conventional therapy in Japanese patients with dyslipidemia and CKD. It would be due in part to the ability of atorvastatin to more potently reduce serum LDL and triglycerides compared to conventional therapy.

Lipid Abnormalities in Type 2 Diabetes Mellitus Patients with Overt Nephropathy

BACKGROUND

Diabetic nephropathy is a major complication of diabetes and an established risk factor for cardiovascular events. Lipid abnormalities occur in patients with diabetic nephropathy, which further increase their risk for cardiovascular events. We compared the degree of dyslipidemia among type 2 diabetes mellitus (T2DM) subjects with and without nephropathy and analyzed the factors associated with nephropathy among them.

METHODS

In this retrospective study, T2DM patients with overt nephropathy were enrolled in the study group (n=89) and without nephropathy were enrolled in the control group (n=92). Both groups were matched for age and duration of diabetes. Data on total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), urea and creatinine were collected from the case sheets. TG/HDL-C ratio, a surrogate marker for small, dense, LDL particles (sdLDL) and estimated glomerular filtration rate (eGFR) were calculated using equations. Multivariate analysis was done to determine the factors associated with eGFR.

RESULTS

Dyslipidemia was present among 56.52% of control subjects and 75.28% of nephropathy subjects (P=0.012). The percentage of subjects with atherogenic dyslipidemia (high TG+low HDL-C+sdLDL) was 14.13 among controls and 14.61 among nephropathy subjects. Though serum creatinine was not significantly different, mean eGFR value was significantly lower among nephropathy patients (P=0.002). Upon multivariate analysis, it was found that TC (P=0.007) and HDL-C (P=0.06) were associated with eGFR among our study subjects.

CONCLUSION

Our results show that dyslipidemia was highly prevalent among subjects with nephropathy. Regular screening for dyslipidemia may be beneficial in controlling the risk for adverse events among diabetic nephropathy patients.

Renin-angiotensin system at the crossroad of hypertension and hypercholesterolemia

AIM

The aim of this study is to discuss the reliable scientific evidence of an interactive link between hypertension and hypercholesterolemia considering the metabolic pathways and the pathogenetic mechanisms connecting the two risk factors.

DATA SYNTHESIS

Hypertension and hypercholesterolemia are highly prevalent in the general population and their coexistence in the same subjects additively increases the risk of cardiovascular disease. Probably, hypercholesterolemia is also a risk factor for the development of hypertension. On the other side, it is also possible that lipid-lowering treatment could improve blood pressure control. Although the mechanisms of interaction between these two risk factors have not been completely elucidated thus far, there is rapidly growing evidence that the involvement of the renin-angiotensin system (RAS) can be considered as the common link between hypertension and hypercholesterolemia. In particular, hypercholesterolemia seems to promote the upregulation of type 1 angiotensin II (AT1) receptor genes because of an increase in the stability of mRNA followed by structural overexpression of vascular AT1 receptors for angiotensin II. The treatment of both risk factors greatly improves individual risk profile, especially when statins and RAS blockers are used together.

CONCLUSIONS

Hypertension and hypercholesterolemia are highly coprevalent and strongly related from a pathophysiological point of view. The RAS could be the main mediator of this link.

Association of renal function with clinical parameters and conditions in a longitudinal population-based epidemiological study

The aim of the present study was to examine the association of renal function with clinical parameters and conditions in the general population. Study subjects comprised 6,027 community-dwelling individuals who were recruited to the Inabe Health and Longevity Study: A longitudinal genetic epidemiological study of atherosclerotic, cardiovascular and metabolic diseases. The cutoff value, which was used to divide the subjects into those with normal and those with low estimated glomerular filtration rate (eGFR), was 60 ml/min/1.73 m2. Bonferroni's correction was applied to establish the statistical significance of the association. Longitudinal analysis using the generalized linear mixed-effect model, following adjustments for age and gender, revealed that the eGFR was significantly associated (P<0.0017) with serum levels of triglycerides, low-density lipoprotein cholesterol, uric acid, blood glycosylated hemoglobin content, fasting plasma glucose and body mass index. These parameters decreased curvilinearly with increases in eGFR. Furthermore, eGFR correlated positively with serum levels of high-density lipoprotein (HDL) cholesterol. Longitudinal analysis using the generalized estimating equation following adjustment for age and gender indicated a significant association (P<0.0024) between eGFR and prevalence of hypertension, type 2 diabetes mellitus, hypo-HDL cholesterolemia, hyperuricemia and obesity. Thus, low eGFR results in detrimental effects on various clinical parameters and conditions, resulting in increased risk of hypertension, dyslipidemia, type 2 diabetes mellitus, hyperuricemia and obesity.

HDL cholesterol and risk of diabetic nephropathy in patient with type 1 diabetes: A meta-analysis of cohort studies

A meta-analysis was conducted to assess the impact of HDL on risk of diabetic nephropathy in T1DM patients. Ten papers containing (7698) participants were included in this meta-analysis. Our meta-analysis suggest that the risk of diabetic nephropathy was decreased with HDL in type 1 diabetes.

Long-Term Visit-to-Visit Blood Pressure Variability and Renal Function Decline in Patients With Hypertension Over 15 Years

BACKGROUND

Visit-to-visit variability of systolic blood pressure (SBP) has been shown to contribute to cardiovascular events and all-cause mortality. However, little is known about its long-term effect on renal function. We aim to examine the relationship between visit-to-visit blood pressure variability (BPV) and decline in renal function in patients with hypertension and to determine the level of systolic BPV that is associated with significant renal function decline.

METHODS AND RESULTS

This is a 15-year retrospective cohort study of 825 hypertensive patients. Blood pressure readings every 3 months were retrieved from the 15 years of clinic visits. We used SD and coefficient of variation as a measure of systolic BPV. Serum creatinine was captured and estimated glomerular filtration rate was calculated at baseline, 5, 10, and 15 years. The mean SD of SBP was 14.2±3.1 mm Hg and coefficient of variation of SBP was 10.2±2%. Mean for estimated glomerular filtration rate slope was -1.0±1.5 mL/min per 1.73 m2 per year. There was a significant relationship between BPV and slope of estimated glomerular filtration rate (SD: r=-0.16, P<0.001; coefficient of variation: r=-0.14, P<0.001, Pearson's correlation). BPV of SBP for each individual was significantly associated with slope of estimated glomerular filtration rate after adjustment for mean SBP and other confounders. The cutoff values estimated by the receiver operating characteristic curve for the onset of chronic kidney disease for SD of SBP was 13.5 mm Hg and coefficient of variation of SBP was 9.74%.

CONCLUSIONS

Long-term visit-to-visit variability of SBP is an independent determinant of renal deterioration in patients with hypertension. Hence, every effort should be made to reduce BPV in order to slow down the decline of renal function.

Efficacy of statins in patients with diabetic nephropathy: a meta-analysis of randomized controlled trials

Background

The effects of statins in patients with diabetic nephropathy are controversial. With increasing interest in the potential therapeutic role of statins in diabetic nephropathy, it is essential to evaluate its real effects.

Methods

PubMed, EMBASE, Web of Science databases, Cochrane Central Register of Controlled Trials and China National Knowledge Infrastructure were systematically searched for randomized controlled trials (RCTs) of statins in patients with diabetic nephropathy.

Results

Fourteen trials with 2866 participants were included in our meta-analysis. Compared with placebo, albuminuria and urinary albumin excretion rates in the statin group were reduced by 0.46 [95 % confidence interval (CI),−0.68 to −0.25, P < 0.0001] and 1.68 (95 % CI, −3.23 to −0.12, P = 0.03), respectively. The reduction of albuminuria was greater in patients of type 2 diabetes mellitus with diabetic nephropathy [standardized mean difference (SMD), −0.56; 95 % CI, −0.80 to −0.32, P < 0.00001] and the decrease was significant during the 1 to 3 years period of statin therapy (SMD, −0.57; 95 % CI, −0.95 to −0.19, P = 0.003). Subgroup analysis demonstrated the effects of statins were much stronger in subjects with pathologic albuminuria: change of −0.71 (95 % CI, −1.09 to −0.33, P = 0.0003) for those with urinary protein excretion 30 to 300 mg/day, −0.37 (95 % CI, −0.67 to −0.06, P = 0.02) for those with excretion more than 300 mg/day and −0.29 (95 % CI, −0.78 to 0.21, P = 0.26) for those with excretion less than 30 mg/day. In contrast, statins did not significantly reduce estimated glomerular filtration rate, serum creatinine and blood urea nitrogen levels.

Conclusions

Statins decrease the albuminuria and urinary albumin excretion rates significantly. The efficacy of statins on renal function is time dependent and better in type 2 diabetic patients with nephropathy.

The Genetic Landscape of Renal Complications in Type 1 Diabetes

Diabetes is the leading cause of ESRD. Despite evidence for a substantial heritability of diabetic kidney disease, efforts to identify genetic susceptibility variants have had limited success. We extended previous efforts in three dimensions, examining a more comprehensive set of genetic variants in larger numbers of subjects with type 1 diabetes characterized for a wider range of cross-sectional diabetic kidney disease phenotypes. In 2843 subjects, we estimated that the heritability of diabetic kidney disease was 35% (P=6.4×10^-3). Genome-wide association analysis and replication in 12,540 individuals identified no single variants reaching stringent levels of significance and, despite excellent power, provided little independent confirmation of previously published associated variants. Whole-exome sequencing in 997 subjects failed to identify any large-effect coding alleles of lower frequency influencing the risk of diabetic kidney disease. However, sets of alleles increasing body mass index (P=2.2×10^-5) and the risk of type 2 diabetes (P=6.1×10^-4) associated with the risk of diabetic kidney disease. We also found genome-wide genetic correlation between diabetic kidney disease and failure at smoking cessation (P=1.1×10^-4). Pathway analysis implicated ascorbate and aldarate metabolism (P=9.0×10^-6), and pentose and glucuronate interconversions (P=3.0×10^-6) in pathogenesis of diabetic kidney disease. These data provide further evidence for the role of genetic factors influencing diabetic kidney disease in those with type 1 diabetes and highlight some key pathways that may be responsible. Altogether these results reveal important biology behind the major cause of kidney disease.

Statins and Renin Angiotensin System Inhibitors Dose-Dependently Protect Hypertensive Patients against Dialysis Risk

Background

Taiwan has the highest renal disease incidence and prevalence in the world. We evaluated the association of statin and renin–angiotensin system inhibitor (RASI) use with dialysis risk in hypertensive patients.

Methods

Of 248,797 patients who received a hypertension diagnosis in Taiwan during 2001–2012, our cohort contained 110,829 hypertensive patients: 44,764 who used RASIs alone; 7,606 who used statins alone; 27,836 who used both RASIs and statins; and 33,716 who used neither RASIs or statins. We adjusted for the following factors to reduce selection bias by using propensity scores (PSs): age; sex; comorbidities; urbanization level; monthly income; and use of nonstatin lipid-lowering drugs, metformin, aspirin, antihypertensives, diuretics, and beta and calcium channel blockers. The statin and RASI use index dates were considered the hypertension confirmation dates. To examine the dose–response relationship, we categorized only statin or RASI use into four groups in each cohort: <28 (nonusers), 28–90, 91–365, and >365 cumulative defined daily doses (cDDDs).

Results

In the main model, PS-adjusted hazard ratios (aHRs; 95% confidence intervals [CIs]) for dialysis risk were 0.57 (0.50–0.65), 0.72 (0.53–0.98), and 0.47 (0.41–0.54) in the only RASI, only statin, and RASI + statin users, respectively. RASIs dose-dependently reduced dialysis risk in most subgroups and in the main model. RASI use significantly reduced dialysis risk in most subgroups, regardless of comorbidities or other drug use (P < 0.001). Statins at >365 cDDDs protected hypertensive patients against dialysis risk in the main model (aHR = 0.62, 95% CI: 0.54–0.71), regardless of whether a high cDDD of RASIs, metformin, or aspirin was used.

Conclusion

Statins and RASIs independently have a significant dose-dependent protective effect against dialysis risk in hypertensive patients. The combination of statins and RASIs can additively protect hypertensive patients against dialysis risk.

Serum Uric Acid Level Predicts Progression of IgA Nephropathy in Females but Not in Males

Background

Immunoglobulin A nephropathy (IgAN) is one of most common forms of glomerulonephritis. At this point, the clinical impact of hyperuricemia on IgAN is not clear. The aim of the present study was to explore the clinical impact of hyperuricemia on the progression of IgAN.

Study Design

Multicenter retrospective cohort study.

Setting & Participants

935 IgAN patients who were diagnosed by kidney biopsy at Osaka University Hospital, Osaka General Hospital, and Osaka Rosai Hospital. were included in this study.

Predictor

Uric acid levels at renal biopsy.

Outcomes

The outcome of interest was the time from the kidney biopsy to the time when a 50% increase in the baseline serum creatinine level was observed, which was defined as "progression".

Measurements

The baseline characteristics according to the kidney biopsy at the time of diagnosis were collected from the medical records, and included age, gender, body mass index, hypertension, diabetes (use of antidiabetic drugs), serum levels of creatinine, urinary protein, smoking status, RAAS blockers and steroid therapy.

Results

An elevated serum uric acid level was an independent risk factor for progression in female patients (per 1.0 mg/dL, multivariate-adjusted incident rate ratio 1.33 [95% confidence interval 1.07, 1.64], P = 0.008) but not in male patients (1.02 [0.81, 1.29], P = 0.855). To control a confounding effect of renal function on an association between serum uric acid level and progression in female patients, age- and serum creatinine-matched and propensity score-matched analyses were performed, and these results also supported the effect by uric acid on kidney disease progression independent of basal kidney function.

Limitations

A cohort analyzed retorospectively.

Conclusions

This study revealed that an elevated uric acid level was an independent risk factor for ESKD in female IgAN patients. Therefore, uric acid might be a treatable target in female IgAN patients.

Risk factors associated with secondary hyperparathyroidism in patients with chronic kidney disease

Secondary hyperparathyroidism (SHPT) is common in patients with chronic kidney disease (CKD), and its development and progression are affected by various factors. The aim of the present study was to identify the risk factors for SHPT in patients with CKD. A retrospective study was performed in 498 patients (305 males and 193 females) with CKD, observed in the The First Hospital of Jilin University between January 2008 and December 2012. The demographic, clinical and laboratory data were collected. Patients were divided into the SHPT group (n=424) with elevated serum parathyroid hormone (PTH) expression levels and the control group (n=74) with normal serum PTH expression levels. Univariate and multivariate regression analyses were employed to explore the risk factors for SHPT. Serum PTH expression levels in women with CKD were significantly higher than in men (P=0.047). Serum PTH expression levels were positively correlated with the expression levels of serum creatinine (P<0.01), phosphorus (P<0.01), C-reactive protein (P<0.05), triglyceride (P<0.05), cholesterol (P<0.05) and low-density lipoprotein cholesterol (P<0.05), but were negatively correlated with the expression levels of hemoglobin (P<0.05), calcium (P<0.01) and CO₂ combining power (P<0.01) in patients with CKD. Multivariate analysis showed that the serum expression levels of creatinine [µmol/l; odds radio (OR), 1.003; 95% confidence interval (CI), 1.002-1.004; P=0.001] and phosphorus (mmol/l; OR, 2.19; 95% CI, 1.254-3.826; P=0.006) in patients with CKD significantly influenced serum PTH expression levels. The SHPT risk factors include female gender, low calcium, high phosphorus, acidosis, anemia, hypertension, hyperlipidemia and micro-inflammation, with blood phosphorus and creatinine being independent risk factors.

Improvement in Renal Function and Reduction in Serum Uric Acid with Intensive Statin Therapy in Older Patients: A Post Hoc Analysis of the SAGE Trial

Background

Improvement in renal function and decreases in serum uric acid (SUA) have been reported following prolonged high-intensity statin (HMG-CoA reductase inhibitor) therapy. This post hoc analysis of the SAGE trial examined the effect of intensive versus less intensive statin therapy on renal function, safety, and laboratory parameters, including SUA, in elderly coronary artery disease (CAD) patients (65–85 years) with or without chronic kidney disease (CKD).

Methods

Patients were randomized to atorvastatin 80 mg/day or pravastatin 40 mg/day and treated for 12 months. Patients were stratified using Modification of Diet in Renal Disease (MDRD) estimated glomerular filtration rates (eGFRs) in CKD (eGFR <60 mL/min/1.73 m²) and non-CKD populations.

Results

Of the 893 patients randomized, 858 had complete renal data and 418 of 858 (49 %) had CKD (99 % Stage 3). Over 12 months, eGFR increased with atorvastatin and remained stable with pravastatin (+2.38 vs. +0.18 mL/min/1.73 m², respectively; p < 0.0001). MDRD eGFR improved significantly in both CKD treatment arms; however, the increased eGFR in patients without CKD was significantly greater with atorvastatin (+2.08 mL/min/1.73 m²) than with pravastatin (−1.04 mL/min/1.73 m²). Modest reductions in SUA were observed in both treatment arms, but a greater fall occurred with atorvastatin than with pravastatin (−0.52 vs. −0.09 mg/dL, p < 0.0001). Change in SUA correlated negatively with changes in eGFR and positively with changes in low-density lipoprotein cholesterol. Reports of myalgia were rare (3.6 % CKD; 5.7 % non-CKD), and there were no episodes of rhabdomyolysis. Elevated serum alanine and aspartate transaminase to >3 times the upper limit of normal occurred in 4.4 % of atorvastatin- and 0.2 % of pravastatin-treated patients.

Conclusion

Intensive management of dyslipidemia in older patients with stable coronary heart disease may have beneficial effects on renal function and SUA.

Electronegative low density lipoprotein induces renal apoptosis and fibrosis: STRA6 signaling involved

Dyslipidemia has been proven to capably develop and aggravate chronic kidney disease. We also report that electronegative LDL (L5) is the most atherogenic LDL. On the other hand, retinoic acid (RA) and RA receptor (RAR) agonist are reported to be beneficial in some kidney diseases. “Stimulated by retinoic acid 6” (STRA6), one retinol-binding protein 4 receptor, was recently identified to regulate retinoid homeostasis. Here, we observed that L5 suppressed STRA6 cascades [STRA6, cellular retinol-binding protein 1 (CRBP1), RARs, retinoid X receptor α, and retinol, RA], but L5 simultaneously induced apoptosis and fibrosis (TGFβ₁, Smad2, collagen 1, hydroxyproline, and trichrome) in kidneys of L5-injected mice and L5-treated renal tubular cells. These L5-induced changes of STRA6 cascades, renal apoptosis, and fibrosis were reversed in kidneys of LOX1^−/− mice. LOX1 RNA silencing and inhibitor of c-Jun N-terminal kinase and p38MAPK rescued the suppression of STRA6 cascades and apoptosis and fibrosis in L5-treated renal tubular cells. Furthermore, crbp1 gene transfection reversed downregulation of STRA6 cascades, apoptosis, and fibrosis in L5-treated renal tubular cells. For mimicking STRA6 deficiency, efficient silencing of STRA6 RNA was performed and was found to repress STRA6 cascades and caused apoptosis and fibrosis in L1-treated renal tubular cells. In summary, this study reveals that electronegative L5 can cause kidney apoptosis and fibrosis via the suppression of STRA6 cascades, and implicates that STRA6 signaling may be involved in dyslipidemia-mediated kidney disease.

Association of statin use and the risk of end-stage renal disease: A nationwide Asian population-based case-control study

BACKGROUND

Although experimental models have shown that statins could alleviate glomerular damage and decrease urinary protein excretion, the renal effects of statins remain unclear. A case-control study was conducted using data from Taiwan's National Health Insurance system.

METHODS

An end-stage renal disease (ESRD) group comprising 11,486 patients was established. Each patient was frequency-matched by age, sex, and comorbidities with one person without ESRD from the general population. Logistic regression analysis was performed to estimate the influence of statin use on ESRD risk.

RESULTS

The overall adjusted odds ratios (ORs) of ESRD among patients who received statins was 1.59 (95% confidence interval=1.50-1.68). The raised ESRD risk of statin remained consolidated regardless of statin type (P<.001), except lovastatin. Further, while stratified by cumulative define daily dose, the risk of ESRD increased with accumulative dosage of statins (P for trend<.001).

CONCLUSION

This population-based case-control study showed that statin use might be associated with increased ESRD risks. Large-scale randomized clinical trial encompassing statins of different kinds and populations of different comorbidities would be helpful to clarify the potential ESRD risks of statin users.

Relationship Between Dyslipidemia and Albuminuria in Hypertensive Adults: A Nationwide Population-Based Study

This study aimed to estimate the relationship between various lipid abnormalities and albuminuria in hypertensive Korean adults. Data obtained from the Korea National Health and Nutrition Examination Survey in 2011 to 2012 were analyzed. The study included 2330 hypertensive participants. Total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were measured. Dyslipidemia parameters were defined as high TG ≥200 mg/dL, low HDL-C as HDL-C <40 mg/dL, high TC/HDL-C as TC/HDL-C ratio ≥4, high TG/HDL-C as TG/HDL-C ratio ≥3.8, and high LDL-C/HDL-C as LDL-C/HDL-C ratio ≥2.5. Albuminuria was defined as a urine albumin to creatinine ratio (ACR) ≥30 mg/g. Women with albuminuria showed significantly higher levels of TG, TC/HDL-C, and TG/HDL-C and a lower level of HDL-C than women without albuminuria (all P < 0.05). LogTG, TC/HDL-C, and logTG/HDL-C were positively correlated with ACR in both men and women; however, HDL-C was negatively correlated with ACR in women and non-HDL-C was positively correlated with ACR in men. In men, there was no association between ACR and lipid parameters. However, in women, higher values for logTG, TC/HDL-C, and logTG/HDL-C were associated with an increased odds ratio (OR) for albuminuria (OR [95% confidence interval]: 1.53 [1.06-2.21], 1.21 [1.02-1.45], and 1.78 [1.21-2.63], respectively) and HDL-C with a decreased OR for albuminuria (0.78 [0.67-0.92]) after adjusting for all covariates. LogTG, TC/HDL-C, and logTG/HDL-C were associated with an increased prevalence of albuminuria in hypertensive women. Screening and treatment for dyslipidemia may be necessary for hypertensive women to address potential albuminuria.

Rationale and Design of the Standard Versus Intensive Statin Therapy for Hypercholesterolemic Patients with Diabetic Retinopathy (EMPATHY) Study: a Randomized Controlled Trial

AIM

Hyperlipidemia and diabetic retinopathy increase the risk of cardiovascular disease (CVD). The standard versus intEnsive statin therapy for hypercholesteroleMic Patients with diAbetic retinopaTHY (EMPATHY) study examines whether intensive lipid-lowering therapy is superior to standard therapy in reducing the incidence of cardiovascular events in patients with hyperlipidemia and diabetic retinopathy, but without a history of coronary artery disease.

METHODS

Patients who had elevated low-density lipoprotein cholesterol (LDL-C) and diabetic retinopathy without a history of coronary artery disease were eligible for the study. Patients were randomly assigned in a 1:1 ratio to receive intensive or standard therapy. Patients are being treated with monotherapy with 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor (statin) for a maximum of 5.5 years to achieve the following LDL-C target: ＜70 mg/dL for the intensive therapy group or ≥100 and ＜120 mg/dL for the standard therapy group. The primary endpoint is a composite of incidence of CVD and death from CVD.

RESULTS

Between May 2010 and October 2013, 5,995 patients were assessed for eligibility, and 5,144 were assigned to the study treatment (2,571 and 2,573 in the intensive and standard therapy groups, respectively), and baseline data were analyzed from 5,107 (2,550 in the intensive therapy group and 2,557 in the standard therapy group).

CONCLUSIONS

This is the first study assessing the benefits of intensive statin therapy in patients with hypercholesterolemia and diabetic retinopathy in a primary prevention setting. Furthermore, this study evaluates the appropriateness of the treat-to-target approach because all patients are treated to achieve specific LDL-C targets by titrating statin therapy.

CLINICAL TRIAL REGISTRATION NUMBER

UMIN000003486.

Podocyte directed therapy of nephrotic syndrome-can we bring the inside out?

Several of the drugs currently used for the treatment of glomerular diseases are prescribed for their immunotherapeutic or anti-inflammatory properties, based on the current understanding that glomerular diseases are mediated by immune responses. In recent years our understanding of podocytic signalling pathways and the crucial role of genetic predispositions in the pathology of glomerular diseases has broadened. Delineation of those signalling pathways supports the hypothesis that several of the medications and immunosuppressive agents used to treat glomerular diseases directly target glomerular podocytes. Several central downstream signalling pathways merge into regulatory pathways of the podocytic actin cytoskeleton and its connection to the slit diaphragm. The slit diaphragm and the cytoskeleton of the foot process represent a functional unit. A breakdown of the cytoskeletal backbone of the foot processes leads to internalization of slit diaphragm molecules, and internalization of slit diaphragm components in turn negatively affects cytoskeletal signalling pathways. Podocytes display a remarkable ability to recover from complete effacement and to re-form interdigitating foot processes and intact slit diaphragms after pharmacological intervention. This ability indicates an active inside-out signalling machinery which stabilizes integrin complex formations and triggers the recycling of slit diaphragm molecules from intracellular compartments to the cell surface. In this review we summarize current evidence from patient studies and model organisms on the direct impact of immunosuppressive and supportive drugs on podocyte signalling pathways. We highlight new therapeutic targets that may open novel opportunities to enhance and stabilize inside-out pathways in podocytes.

Predictors of Peak Troponin Level in Acute Coronary Syndromes: Prior Aspirin Use and SYNTAX Score

The peak troponin level has been associated with cardiovascular (CV) mortality and adverse CV events. The association of peak troponin with CV risk factors and severity and complexity of coronary artery disease remains unknown. We assessed the predictors of peak troponin in patients with acute coronary syndrome (ACS). This study aims to determine the predictors of peak troponin in ACS. Cardiac catheterization (CC) reports and electronic medical records from 2010 to 2013 were retrospectively reviewed. A total of 219 patients were eligible for the study. All major CV risk factors, comorbidities, laboratory data, CC indications, and coronary lesion characteristics were included. Univariate and multivariate regression analyses were done. On multivariate linear regression analysis, ST-elevation myocardial infarction (p = 0.001, β = 65.16) and increasing synergy between percutaneous coronary intervention with Taxus and cardiac surgery (SYNTAX) score (p = 0.002, β = 1.15) were associated with higher peak troponin. The Pearson correlation between SYNTAX score and peak troponin was r = 0.257, p = 0.001. History of daily aspirin use was associated with lower peak troponin (p = 0.002, β = -24.32). Prior statin use (p = 0.321, β = -8.98) and the presence of CV risk factors were not associated with peak troponin. Coronary artery disease severity and complexity, urgency of CC, and prior aspirin use are associated with peak troponin levels in ACS. Our findings may help predict patient population with ACS who would be at a greater risk for short- and long-term CV morbidity and mortality due to elevated peak troponin.

Effects of Atorvastatin Dose and Concomitant Use of Angiotensin-Converting Enzyme Inhibitors on Renal Function Changes over Time in Patients with Stable Coronary Artery Disease: A Prospective Observational Study

Angiotensin-converting enzyme inhibitors (ACEI) and statins are widely used in patients with coronary artery disease (CAD). Our aim was to compare changes in glomerular filtration rate (GFR) over time in subjects with stable CAD according to atorvastatin dose and concomitant use of ACEI. We studied 78 men with stable CAD referred for an elective coronary angiography who attained the then-current guideline-recommended target level of low-density lipoproteins (LDL) cholesterol below 2.5 mmol/L in a routine fasting lipid panel on admission and were receiving atorvastatin at a daily dose of 10-40 mg for ≥3 months preceding the index hospitalization. Due to an observational study design, atorvastatin dosage was not intentionally modified for other reasons. GFR was estimated during index hospitalization and at about one year after discharge from our center. Irrespective of ACEI use, a prevention of kidney function loss was observed only in those treated with the highest atorvastatin dose. In 38 subjects on ACEI, both of the higher atorvastatin doses were associated with increasing beneficial effects on GFR changes (mean ± SEM: -4.2 ± 2.4, 1.1 ± 1.6, 5.2 ± 2.4 mL/min per 1.73 m² for the 10-mg, 20-mg and 40-mg atorvastatin group, respectively, p = 0.02 by ANOVA; Spearman's rho = 0.50, p = 0.001 for trend). In sharp contrast, in 40 patients without ACEI, no significant trend effect was observed across increasing atorvastatin dosage (respective GFR changes: -1.3 ± 1.0, -4.7 ± 2.1, 4.8 ± 3.6 mL/min per 1.73 m², p = 0.02 by ANOVA; rho = 0.08, p = 0.6 for trend). The results were substantially unchanged after adjustment for baseline GFR or time-dependent variations of LDL cholesterol. Thus, concomitant ACEI use appears to facilitate the ability of increasing atorvastatin doses to beneficially modulate time-dependent changes in GFR in men with stable CAD.

The effect of statins on microalbuminuria, proteinuria, progression of kidney function, and all-cause mortality in patients with non-end stage chronic kidney disease: A meta-analysis

Conclusive evidence regarding the effect of statins on non-end stage chronic kidney disease (CKD) has not been reported previously. This meta-analysis evaluated the association between statins and microalbuminuria, proteinuria, progression, and all-cause mortality in patients with non-end stage CKD. Databases (e.g., PubMed, Embase and the Cochrane Library) were searched for randomized controlled trials (RCTs) with data on statins, microalbuminuria, proteinuria, renal health endpoints, and all-cause mortality patients with non-end stage CKD to perform this meta-analysis. The mean difference (MD) of the urine albumin excretion ratios (UAER), 24-h urine protein excretion, and risk ratios (RR) of all-cause mortality and renal health endpoints were calculated, and the results are presented with 95% confidence intervals (CI). A total of 23 RCTs with 39,419 participants were selected. The analysis demonstrated that statins statistically reduced UAER to 26.73 μg/min [95%CI (-51.04, -2.43), Z=2.16, P<0.05], 24-h urine protein excretion to 682.68 mg [95%CI (-886.72, -478.63), Z=6.56, P<0.01] and decreased all-cause mortality [RR=0.78, 95%CI (0.72, 0.84), Z=6.08, P<0.01]. However, the analysis results did not indicate that statins reduced the events of renal health endpoints [RR=0.96, 95%CI (0.91,1.01), Z=1.40, P>0.05]. In summary, our study indicates that statins statistically reduced microalbuminuria, proteinuria, and clinical deaths, but statins did not effectively slow the clinical progression of non-end stage CKD.

Short-term effects of lovastatin therapy on proteinuria of type 2 diabetic nephropathy: A clinical trial study

Background:

Diabetic nephropathy (DN) is characterized by albuminuria, hypertension, and a progressive decline in glomerular filtration rate. The 3-hydroxy-3-methylglutaryl coenzyme A is a well-known agent that is active in lowering total plasma and low-density lipoprotein cholesterol (LDL-C) levels in cases with hypercholesterolemia. Hence, in this study, proteinuria changes at the beginning and after the withdrawal of lovastatin in patients with type 2 DN (T2DN) were studied.

Materials and Methods:

Lovastatin was administered for thirty male patients with T2DN and then was withdrawn. Twenty-four hours, urine creatinine and protein levels were determined.

Results:

The mean levels of total cholesterol and LDL-C were reduced without any change in the triglyceride (TG) level while the high-density lipoprotein cholesterol (HDL-C) level was increased. There was a reverse linear correlation between the changes in the level of HDL-C and the changes in the level of 24 h urine protein after 90 days of lovastatin therapy (P = 0.007, r = −0.484).

Conclusions:

Short-term 3-month lovastatin therapy has no effect on proteinuria levels in patients with T2DN despite the antihyperlipidemic effects and reverse correlation of proteinuria with HDL-C.

Effects of pitavastatin add-on therapy on chronic kidney disease with albuminuria and dyslipidemia

Background

In non-dialysis chronic kidney disease (CKD) patients with dyslipidemia, statin therapy is recommended to prevent cardiovascular complications. Dyslipidemia has been also shown to be an independent risk factor for the progression of CKD. However, it is still unclear whether statin therapy exerts an inhibitory effect on renal deterioration in CKD patients with dyslipidemia. The purpose of the present study was to examine possible therapeutic effects of statin add-on therapy on renal function as well as parameters of lipid and glucose metabolism, arterial stiffness and oxidative stress, in comparison to diet therapy, in CKD patients with dyslipidemia.

Methods

This study was a randomized, open-label, and parallel-group trial consisted of a 12-months treatment period in non-dialysis CKD patients with alubuminuria and dyslipidemia. Twenty eight patients were randomly assigned either to receive diet counseling alone (diet therapy group) or diet counseling plus pitavastatin (diet-plus-statin therapy group), to achieve the LDL-cholesterol (LDL-C) target of <100 mg/dl.

Results

The statin treatment by pitavastatin was well tolerated in all of the patients without any significant adverse events and the average dose of pitavastatin was 1.0 ± 0.0 mg daily after treatment. After the 12-months treatment period, LDL-C was significantly lower in the diet-plus-statin therapy group compared with the diet therapy group (diet vs diet-plus-statin: LDL-C, 126 ± 5 vs 83 ± 4 mg/dL, P < 0.001). On the other hand, the diet-plus-statin therapy did not significantly reduce albuminuria or delay the decline in eGFR compared with the diet therapy, and there was no relationship between the change in LDL-C and the change in eGFR or albuminuria. However, diet therapy as well as diet-plus-statin therapy exerted similar lowering effects on the pentosidine levels (diet therapy group, baseline vs 12 months: 40 ± 4 vs 24 ± 3 ng/mL, P = 0.001; diet-plus-statin therapy, 46 ± 7 vs 34 ± 6 ng/mL, P = 0.008). Furthermore, the results of multivariate regression analysis indicated that the change in pentosidine was a significant contributor to the change in eGFR (β = −0.536, P = 0.011).

Conclusions

Although statin add-on therapy did not show additive renal protective effects, the diet therapy as well as the diet-plus-statin therapy could contribute to the reduction in plasma pentosidine in CKD patients with albuminuria and dyslipidemia.

The Effects of Simvastatin on Proteinuria and Renal Function in Patients with Chronic Kidney Disease

Current data suggests that statins might have beneficial effects on renal outcomes. Beneficial effects of statin treatment on renal progression in advanced chronic kidney disease (CKD) are obviously controversial. In a retrospective, controlled study, the authors have evaluated the effects of 53-week treatment with simvastatin, versus no treatment on proteinuria and renal function among 51 patients with CKD stages III-IV. By the end of the 53-week treatment, urine protein excretion decreased from 0.96 (IQR 0.54, 2.9) to 0.48 (IQR 0.18, 0.79) g/g creatinine (P < 0.001) in patients treated with simvastatin in addition to ACEI and ARBs, while no change was observed among the untreated patients. Moreover, a significantly greater decrease in urine protein excretion was observed in the simvastatin group as compared with the untreated group. The mean changes of serum creatinine and eGFR did not significantly differ in both groups. A significantly greater decrease in total cholesterol and LDL-cholesterol was found in the simvastatin group than in the untreated group. In summary, apart from lipid lowering among CKD patients, ingesting simvastatin was associated with a decrease in proteinuria. These statin effects may become important for supportive therapy in renal damage in the future.

The association of albuminuria and high-sensitivity C-reactive protein with the efficacy of HMG-coenzyme A reductase inhibitors for cardiovascular event prevention

BACKGROUND

It is not clear which hypercholesterolemic patients benefit most from β-hydroxy-β-methylglutaryl coenzyme A reductase inhibitors with respect to the prevention of cardiovascular events. Early signs of atherosclerotic vascular damage may identify high-risk patients.

DESIGN

We studied whether subjects with hypercholesterolemia will benefit more from starting statin treatment in the case of high albuminuria and/or high-sensitivity C-reactive protein (hsCRP).

METHODS

Included were subjects who had hypercholesterolemia at baseline, a negative cardiovascular disease history and who were not treated with statins. In total, 2011 subjects were analysed, of whom 695 started with a statin during a follow-up of 7.0 ± 1.7 years. Adjusted hazard ratios (HRs) for cardiovascular events were calculated in subjects who started versus those who did not start a statin stratified for albuminuria less than or ≥ 15 mg/day and/or hsCRP less than or ≥ 3 mg/L.

RESULTS

The start of a statin was associated with a beneficial effect on cardiovascular risk in subjects with high albuminuria (HR 0.38 (0.23-0.60)), while the effect of starting a statin was non-significant in subjects with low albuminuria (HR 0.74 (0.44-1.24), P for interaction < 0.05). The effect of starting a statin was similar in subgroups with high and low hsCRP (P for interaction 0.34). When combining albuminuria and hsCRP subgroups, the start of statin treatment was associated with a lower risk of cardiovascular events dependent on albuminuria and not on the hsCRP level.

CONCLUSIONS

The start of statin treatment is associated with a significantly lower absolute as well as relative risk of cardiovascular events in subjects with hypercholesterolemia and elevated albuminuria, whereas these drugs had less effect in subjects with normal albuminuria.

Long-Term Mortality After Invasive Angiography and Endovascular Revascularization in Patients With PAD Having Chronic Kidney Disease

Peripheral arterial disease (PAD) and chronic kidney disease (CKD) are associated with increased mortality rates. We assessed long-term outcomes of patients with PAD and CKD. Patients with PAD undergoing invasive angiography and/or endovascular revascularization between 2005 and 2010 were retrospectively classified into 5 CKD stages. A follow-up was performed and 572 patients were included, 116 patients (20%) had normal renal function, 245 were in CKD stage 2 (43%), 156 in CKD stage 3 (27%), and 55 in CKD stages 4 + 5 (10%). Diabetes mellitus, hypertension, and anemia were more frequent in higher CKD stages ( P < .03). During follow-up (mean 1135 days; 95% confidence interval 1159-1259), cumulative mortality was 21% and increased with advanced CKD stages (9%, 16%, 29%, and 47%, respectively, P < .001). In multivariate Cox regression models, higher CKD stages were significantly associated with poor survival. Medication adherence for secondary prevention was significantly lower than recommended but irrespective of CKD stages. Kidney function is an independent predictor of worse long-term survival in patients with PAD. While standard medications were used less often than recommended, no differences between CKD stages were noted.

Hypertriglyceridemia Is Independently Associated with Renal, but Not Retinal Complications in Subjects with Type 2 Diabetes: A Cross-Sectional Analysis of the Renal Insufficiency And Cardiovascular Events (RIACE) Italian Multicenter Study

Objective

Atherogenic dyslipidemia seems to play a major role in microvascular complications and in residual microvascular risk after statin therapy, which reduces triglycerides up to 40%. We assessed whether raised TG levels are associated with an increased burden from microvascular complications in patients with type 2 diabetes.

Methods

Subjects from the Renal Insufficiency And Cardiovascular Events (RIACE) Italian Multicentre Study (n=15,773) were divided in 4 groups depending on whether they had plasma triglycerides below (NTG, 67.8%) or above (HTG, 32.2%) 1.7 mmol/L and were (42.4%) or not on (57.6%) statin therapy. Estimated GFR (eGFR) was calculated from serum creatinine, albuminuria was measured by immunonephelometry or immunoturbidimetry, and retinopathy was evaluated by fundus examination.

Results

HTG subjects, either with or without statin, had higher prevalence of albuminuria, reduced eGFR and chronic kidney disease (CKD), especially the albuminuric forms, but not of retinopathy, than NTG subjects. In contrast, cardiovascular disease and advanced DR were more prevalent in subjects on statin than in those not, independently of triglyceride levels. Logistic regression analysis confirmed that HTG, without or with statin, was independently associated with micro and macroalbuminuria, mildly to severely reduced eGFR, and all CKD phenotypes, but not with retinopathy. The adjusted odd ratios for CKD increased linearly for every 0.26 mmol/L increase (approximately one decile) in triglyceride levels. The increase was higher with increasing severity of albuminuria, eGFR loss and CKD phenotype as well as in subjects receiving than in those not receiving statin treatment.

Conclusions

Triglycerides are associated with CKD, but not retinopathy in subjects with type 2 diabetes, independently of statin treatment. These data point to a possible role of hypertriglyceridemia in the development of CKD, though it remains to be demonstrated that diabetic individuals might benefit from triglyceride reduction with statins and eventually with combination therapy with fibrates.

Trial Registration

www.ClinicalTrials.gov NCT00715481

Pleiotropic effects of type 2 diabetes management strategies on renal risk factors

In parallel with the type 2 diabetes pandemic, diabetic kidney disease has become the leading cause of end-stage renal disease worldwide, and is associated with high cardiovascular morbidity and mortality. As established in landmark randomised trials and recommended in clinical guidelines, prevention and treatment of diabetic kidney disease focuses on control of the two main renal risk factors, hyperglycaemia and systemic hypertension. Treatment of systemic hypertension with angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers is advocated because these drugs seem to exert specific renoprotective effects beyond blood pressure lowering. Emerging evidence shows that obesity, glomerular hyperfiltration, albuminuria, and dyslipidaemia might also adversely affect the kidney in diabetes. Control of these risk factors could have additional benefits on renal outcome in patients with type 2 diabetes. However, despite multifactorial treatment approaches, residual risk for the development and progression of diabetic kidney disease in patients with type 2 diabetes remains, and novel strategies or therapies to treat the disease are urgently needed. Several drugs used in the treatment of type 2 diabetes are associated with pleiotropic effects that could favourably or unfavourably change patients' renal risk profile. We review the risk factors and treatment of diabetic kidney disease, and describe the pleiotropic effects of widely used drugs in type 2 diabetes management on renal outcomes, with special emphasis on antihyperglycaemic drugs.

Xuezhikang () reduced renal cell apoptosis in streptozocin-induced diabetic rats through regulation of Bcl-2 family

OBJECTIVE

To investigate the effect of Xuezhikang (, XZK) on renal cell apoptosis in diabetic rats and the possible mechanism.

METHODS

Sixty-six rats were randomly divided into 3 groups: the normal, model and XZK groups. In each group, the rats were further randomly divided into 3-month and 6-month subgroups, respectively. Diabetes of rats was induced by a single intraperitoneal injection of 1% streptozocin at 60 mg/kg body weight. Rats in the XZK group received gastric perfusion of XZK (1200 mg/kg body weight) everyday for 3 or 6 months, while rats in the normal and model groups received equal volume of saline. Twenty-four hours' urine was collected for urinary albumin excretion (UAE) measurement. Periodic acid-Schiff (PAS) and Masson's trichrome staining were used for saccharides and collagen detection. Cell apoptosis of renal cortex was investigated by TdT-mediated dUTP nick end labeling (TUNEL) staining. Bax and Bcl-2 expressions were detected by immunohistochemistry and Western blot, respectively. Cytochrome C (Cyt C) and caspase-9 concentration were detected by Western blot.

RESULTS

Compared with the model group, XZK treatment could significantly decrease the kidney hypertrophy index, 24 h UAE, renal cell apoptosis, cytoplasmic Cyt C level and active caspase-9 level, as well as suppress the increment of Bax and up-regulate the expression of Bcl-2, leading to the suppression of Bax/Bcl-2 ratio at 3 and 6 months (P<0.05 or P<0.01). Moreover, XZK treatment could alleviate the deposition of PAS-stained saccharides and Masson's trichromestained collagen to different extent.

CONCLUSIONS

Renal cell apoptosis was observed in diabetic kidney, in which mitochondrial apoptotic pathway might be involved. XZK treatment could attenuate pathological changes in diabetic kidney and reduce renal cell apoptosis, probably via the suppression of Bax/Bcl-2 ratio, which lead to inhibition of Cyt C release and following caspase-9 activation.

Should we use statins in all patients with chronic kidney disease without dialysis therapy? The current state of knowledge

PURPOSE

The aim of this article was to present the most important matters associated with dyslipidemia treatment in CKD patients. Moreover, the most important recommendations of the current (2013) KDIGO clinical practice guideline for lipid management in chronic kidney disease are presented.

METHODS

Authors looked through the most recent large clinical trials and meta-analyses and presented their results. We searched using the electronic databases [MEDLINE, EMBASE, Scopus, DARE]. Additionally, abstracts from national and international cardiovascular meetings were studied.

RESULTS

Analysis results suggest that statins exert beneficial effects on kidney since they considerably reduce 24 h urinary protein excretion and are associated with a rise in GFR. Beneficial effects of statins may be influenced by kidney disease stage, doses of medicine and treatment duration. Data suggest that statins are effective and safe for secondary prevention of CV events in individuals with mild CKD. Patients treated with statins had decreased frequency of major atherosclerotic events compared with placebo, reduced risk of CV mortality and deaths from all causes.

CONCLUSIONS

Meta-analyses results suggest that statins are associated with lipid lowering, cardiovascular and anti-proteinuric benefits in CKD patients. However, their effects on overall and cardiovascular mortality are much less obvious. Bearing in mind the advantageous effects and low risk of adverse effects, it seems that mild renal impairment should not exclude these patients from receiving a statin. However, because CKD patients in stages III-V are underrepresented in clinical trials, administration of statins to these patients who have not yet had a vascular event remains controversial.

Effects of atorvastatin and rosuvastatin on renal function in patients with type 2 diabetes mellitus

We performed this population-based study to investigate the effects of atorvastatin and rosuvastatin on renal function in patients with type 2 diabetes. From the Taiwan National Health Insurance Pay-for-Performance program for diabetes mellitus database, 2006 to 2009, type 2 diabetic patients aged 40 to 100 years with the first prescription of atorvastatin or rosuvastatin were identified. All the data were linked to the National Health Insurance claims database, 2000 to 2010, to construct longitudinal health care data. The Modification of Diet in Renal Disease equation was used to calculate the estimated glomerular filtration rate (eGFR), and the eGFRs between baseline and the end of follow-up (maximum 2 years) were compared. Totally, 3,601 new users of atorvastatin and 1,968 new users of rosuvastatin were included. The median follow-up was 238 days in atorvastatin users and 210 days in rosuvastatin users. The eGFR at baseline was 72.3 ± 25.9 ml/min/1.73 m(2) in atorvastatin users and 73.7 ± 27.3 ml/min/1.73 m(2) in rosuvastatin users. In both statin groups, we found no significant change in eGFR (+0.1 ml/min/1.73 m(2), 95% confidence interval -0.4 to 0.7, p = 0.62 in atorvastatin users; -0.1 ml/min/1.73 m(2), 95% confidence interval -0.8 to 0.6, p = 0.77 in rosuvastatin users). In conclusion, neither treatment with atorvastatin nor rosuvastatin was associated with a significant change of renal function in type 2 diabetic patients.

Lipid levels and renal function decline in pre-dialysis patients

Background

Little is known about the effect of low-density lipoprotein (LDL) cholesterol, triglyceride (TG), and high-density lipoprotein (HDL) cholesterol levels on renal function decline in patients receiving specialized pre-dialysis care.

Methods

In the prospective PREPARE-2 study, incident patients starting pre-dialysis care were included when referred to one of the 25 participating Dutch specialized pre-dialysis outpatient clinics (2004-2011). Clinical and laboratory data were collected every 6 months. A linear mixed model was used to compare renal function decline between patients with LDL cholesterol, TG, or HDL cholesterol levels above and below the target goals (LDL cholesterol: <2.50 mmol/l, TG: <2.25 mmol/l, and HDL cholesterol: ≥1.00 mmol/l). Additionally the HDL/LDL cholesterol ratio was investigated (≥0.4).

Results

In our study population (n = 306), the median age was 69 years and 70% were male. Patients with LDL cholesterol levels above the target of 2.50 mmol/l experienced an accelerated renal function decline compared to patients with levels below the target (crude additional decline: 0.10 ml/min/1.73 m²/month, 95% CI 0.00-0.20; p < 0.05). A similar trend was found for TG levels above the target of 2.25 mmol/l (0.05 ml/min/1.73 m²/month, 95% CI −0.06 to 0.16) and for a HDL/LDL cholesterol ratio below 0.4 (0.06 ml/min/1.73 m²/month, 95% CI −0.05 to 0.18). Adjustment for potential confounders resulted in similar results, and the exclusion of patients who were prescribed lipid-lowering medication (statin, fibrate, or cholesterol absorption inhibitor) resulted in a slightly larger estimated effect.

Conclusion

High levels of LDL cholesterol were associated with an accelerated renal function decline, independent of the prescription of lipid-lowering medication.

A novel therapeutic effect of statins on nephrogenic diabetes insipidus

Statins competitively inhibit hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase, resulting in reduced plasma total and low-density lipoprotein cholesterol levels. Recently, it has been shown that statins exert additional 'pleiotropic' effects by increasing expression levels of the membrane water channels aquaporin 2 (AQP2). AQP2 is localized mainly in the kidney and plays a critical role in determining cellular water content. This additional effect is independent of cholesterol homoeostasis, and depends on depletion of mevalonate-derived intermediates of sterol synthetic pathways, i.e. farnesylpyrophosphate and geranylgeranylpyrophosphate. By up-regulating the expression levels of AQP2, statins increase water reabsorption by the kidney, thus opening up a new avenue in treating patients with nephrogenic diabetes insipidus (NDI), a hereditary disease that yet lacks high-powered and limited side effects therapy. Aspects related to water balance determined by AQP2 in the kidney, as well as standard and novel therapeutic strategies of NDI are discussed.