HMG CoA reductase inhibitors (statins) for dialysis patients

Association of albumin to non-high-density lipoprotein cholesterol ratio with mortality in peritoneal dialysis patients

OBJECTIVE

Malnutrition and inflammation are associated with mortality in peritoneal dialysis (PD) patients. Serum albumin and non-high-density lipoprotein cholesterol (non-HDL-C) are independently associated with mortality in PD patients. Combining albumin and non-HDL-C with mortality may be more plausible in clinical practice.

METHODS

This retrospective cohort study included 1954 Chinese PD patients from 1 January 2009 to 31 December 2016. Kaplan-Meier curve was used to determine the relationship between albumin to non-HDL-C ratio and all-cause mortality. Cox regression analysis was applied to assess the independent predictive value while adjusting for confounding factors. Competitive risk analysis was used to examine the effects of other outcomes on all-cause mortality prognosis.

RESULTS

In the 33-month follow-up period, there were 538 all-cause deaths. Kaplan-Meier analysis presented significant differences in all-cause mortality. Multivariate Cox regression showed that the risk of all-cause mortality was lower in the moderate group (9.36-12.79) (HR, 0.731; 95% CI, 0.593-0.902, p = 0.004) and the highest group (>12.79) (HR, 0.705; 95% CI, 0.565-0.879, p = 0.002) compared to the lowest group (≤9.36). Competitive risk analysis revealed significant differences for all-cause mortality (p < 0.001), while there was no statistical significance for other competing events.

CONCLUSIONS

Low albumin to non-HDL-C ratio was associated with a high risk of all-cause mortality in PD patients. It may serve as a potential prognostic biomarker in PD patients.

What's the Optimal Lipids Level for Dialysis Patients? A Cohort Study from a Chinese Dialysis Center in a University Hospital

BACKGROUND

With lipid level being a major contributing factor for cardiovascular health, the high cardiovascular mortality among dialysis patients has raised substantial concerns in regard to the optimal lipid level in these patient population.

OBJECTIVE

To explore the optimal lipid level for the survival of dialysis patients.

METHODS

The lipid profile was measured for each patient. All participants were followed throughout the course of the study. Cox proportional hazards analysis was performed to analyze the prognostic value of lipid level on the survival of these patients.

RESULTS

In our study that included 311 stable maintenance dialysis patients, 54.98% of the participants had LDL-C level ≥100 mg/dl and 82.91% of the patients with triglycerides ≥200 mg/dl had non-HDL level ≥130 mg/dl. During the follow-up period of 48.0 (18.0, 55.5) months, 149 (47.91%) participants died. Among those who died, 59 patients died of cardiovascular disease (CVD) and 33 patients died of ischemic CVD (12.0, 4.7, and 2.7 events per 100 patient-years, respectively). Patients with LDL-C 100-130 mg/dl or non-HDL 130-160 mg/dl had a lower all-cause mortality rate than those who did not meet these criteria. After adjusting for the traditional and ESRD-related risk factors, non-HDL was found to be the independent risk factor for the all-cause mortality. Compared to those patients with non-HDL 130-160 mg/dl, patients with non-HDL <100 mg/dl, 100-130 mg/dl, 160-190 mg/dl, or ≥190 mg/dl all had higher all-cause mortality: HR (95% CI) 3.207 (1.801, 5.713), 2.493 (1.485, 4.184), 2.476 (1.423, 4.307), and 1.917 (1.099, 3.345), respectively. There were no differences in nutrition, comorbidity, and inflammation indices among the patients with different non-HDL groups. However, patients with non-HDL of 130-160 mg/dl had the lowest corrected calcium and calcium phosphate product values as compared with other non-HDL groups.

CONCLUSION

Our study demonstrated that non-HDL 130-160 mg/dl might be the most appropriate lipid level in our dialysis patients. Our follow-up data also showed that patients with higher lipid level had poorer prognosis, just as in the general population.

Impact of HMG-CoA reductase inhibitors on the incidence of polyomavirus-associated nephropathy in renal transplant recipients with human BK polyomavirus viremia

BACKGROUND

Up to 20% of renal transplant recipients (RTR) will develop human BK polyomavirus (BKPyV) viremia. BKPyV viremia is a pre-requisite of polyomavirus-associated nephropathy (PyVAN). Risk of BKPyV infections increases with immunosuppression. Currently, the only effective therapy against PyVAN is reductions in immunosuppression, but this may increase the risk of rejection. In vitro data have shown that pravastatin dramatically decreased caveolin-1 expression in human renal proximal tubular epithelial cells (HRPTEC) and suppressed BKPyV infection in these cells. Based on these data, we postulated that statin therapy may prevent the progression of BKPyV viremia to PyVAN.

PATIENTS AND METHODS

A multicenter, retrospective study was conducted in adult RTR transplanted between July 2005 and March 2012. All patients with documented BKPyV viremia (viral load >500 copies/mL on 2 consecutive tests) were included. Group I consisted of patients taking a statin before the BKPyV viremia diagnosis (n = 32), and Group II had no statin exposure before or after the BKPyV viremia diagnosis (n = 36). The primary endpoint was the incidence of PyVAN.

RESULTS

Demographic data, transplant characteristics, and the degree of immunosuppression (i.e., induction/maintenance therapies, rejection treatment) were similar between the groups, with the exception of more diabetics in Group I. The incidence of PyVAN was comparable between the 2 groups (Group I = 28.1% vs. Group II = 41.7%; P = 0.312).

CONCLUSIONS

Despite the proven in vitro effectiveness of pravastatin preventing BKPyV infection in HRPTEC, statins at doses maximized for cholesterol lowering, in RTR with BKPyV viremia, did not prevent progression to PyVAN.

The associations of uric acid, cardiovascular and all-cause mortality in peritoneal dialysis patients

AIMS

To investigate whether uric acid (UA) is an independent predictor of cardiovascular (CV) and all-cause mortality in peritoneal dialysis (PD) patients after controlling for recognized CV risk factors.

METHODS

A total of 2264 patients on chronic PD were collected from seven centers affiliated with the Socioeconomic Status on the Outcome of Peritoneal Dialysis (SSOP) Study. All demographic and laboratory data were recorded at baseline. Multivariate Cox regression was used to calculate the hazard ratio (HR) of CV and all-cause mortality with adjustments for recognized traditional and uremia-related CV factors.

RESULTS

There were no significant differences in baseline characteristics between patients with (n = 2193) and without (n = 71) UA measured. Each 1 mg/dL of increase in UA was associated with higher all-cause mortality with 1.05(1.00∼1.10) of HR and higher CV mortality with 1.12 (1.05∼1.20) of HR after adjusting for age, gender and center size. The highest gender-specific tertile of UA predicted higher all-cause mortality with 1.23(1.00∼1.52) of HR and higher CV mortality with 1.69 (1.21∼2.38) of HR after adjusting for age, gender and center size. The predictive value of UA was stronger in patients younger than 65 years without CV disease or diabetes at baseline. The prognostic value of UA as both continuous and categorical variable weakened or disappeared after further adjusted for uremia-related and traditional CV risk factors.

CONCLUSIONS

The prognostic value of UA in CV and all-cause mortality was weak in PD patients generally, which was confounded by uremia-related and traditional CV risk factors.

Importance of high-density lipoprotein quality: evidence from chronic kidney disease

PURPOSE OF REVIEW

This review will examine advances in our understanding of the association between high-density lipoprotein (HDL) function and cardiovascular disease (CVD) in patients with chronic kidney disease (CKD).

RECENT FINDINGS

Large randomized statin trials and related meta-analyses confirm that lipid-lowering therapy benefits patients with mild to moderate CKD, leaving a degree of residual cardiovascular risk similar to that documented in the general population. However, patients with advanced CKD on dialysis show little to no cardiovascular benefits from lipid-lowering therapy and have an exaggerated residual cardiovascular risk. HDL quantity and functionality may explain some of the residual risk. CKD modulates the level, composition and functionality of HDL, including impaired cholesterol acceptor function and pro-inflammatory effects. Although these abnormalities prevail in CKD, they do not track together and thus support the idea of separate and distinct mechanistic pathways for each of these critical functions of HDL.

SUMMARY

CKD-induced perturbations in HDL composition, metabolism and functionality may contribute to the excess CVD in patients with CKD and present new therapeutic targets for intervention in this population.

Statin use and calcific uremic arteriolopathy: a matched case-control study

BACKGROUND

Calcific uremic arteriolopathy (CUA), also known as calciphylaxis, is characterized by vascular calcification, thrombosis and intense inflammation. Prior research has shown that statins have anticalcification, antithrombotic and antiinflammatory properties; however, the association between statin use and CUA has not been investigated.

METHODS

This matched case-control study included 62 adult maintenance hemodialysis (HD) patients with biopsy-confirmed CUA diagnosed between the years 2002 and 2011 (cases). All cases were hospitalized at the time of diagnosis. Controls (n = 124) were hospitalized maintenance HD patients without CUA (matched to cases by gender and timing of hospitalization). Univariate and multivariable logistic regression models were applied to compute odds ratio (OR) and 95% confidence intervals (CI) for CUA in statin users, and also to examine previously described associations.

RESULTS

The mean age of cases was 58 years. Most were females (68%), and of white race (64%). Statin use was more common in controls than in cases (39 vs. 19%, p < 0.01). Statin use was associated with lower odds of CUA in unadjusted (OR 0.38, 95% CI 0.18-0.79) and adjusted (OR 0.20, 95% CI 0.05-0.88) analyses. Hypercalcemia (OR 2.25, 95% CI 1.14-4.43), hypoalbuminemia (OR 5.73, 95% CI 2.79-11.77), calcitriol use (OR 5.69, 95% CI 1.02-31.77) and warfarin use (OR 4.30, 95% CI 1.57-11.74) were positively associated with CUA in adjusted analyses whereas paricalcitol and doxercalciferol were not (OR 1.33, 95% CI 0.54-3.27).

CONCLUSION

Statin use may be negatively associated with odds of CUA. Further large prospective studies with attention to potential confounders are needed to confirm these findings.

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

BACKGROUND

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

PURPOSE

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

DATA SOURCES

Cochrane and EMBASE databases (inception to February 2012).

STUDY SELECTION

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

DATA EXTRACTION

Two independent reviewers extracted data and assessed risk of bias.

DATA SYNTHESIS

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

LIMITATION

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

CONCLUSION

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

Effectiveness of statins in chronic kidney disease

BACKGROUND

Previous studies show that statins reduce total cholesterol (TC) concentration by both 21% in primary prevention (PP) and secondary prevention (SP) in clinical trials and by ∼24% in the general population. There are few data about the efficacy of statins on TC concentration and cardiovascular (CV) outcome in patients with chronic kidney disease (CKD). We evaluated the reduction of TC concentration and subsequent risk of CV morbidity and mortality with statins in CKD patients.

METHODS

A population-based cohort study using a record-linkage database in Tayside, Scotland. A total of 2369 patients who had a primary diagnosis of CKD from Scottish Morbidity Record data or biochemistry database (serum creatinine of 220 μmol/l or higher) and who had at least two separate TC measurements between 1993 and 2007 were studied. Patients were categorized into statin-exposed and statin-unexposed groups according to statin use status during the follow-up. They were also classified into PP (n = 1325) and SP (n = 1044) cohorts at the entry date. The main outcomes were TC concentration change from baseline, CV events [Antiplatelet Trialist's Collaboration (APTC)] and all-cause mortality during the follow-up. Cox regression models, in which statin use was a time-dependent variable, were employed to assess the risk of outcome and adjusted for other known confounders.

RESULTS

Statin-associated TC concentrations decreased by 0.59 mmol/l (12%) in PP cohort and 0.56 mmol/l (13%) in SP cohort from 4.77 and 4.48 mmol/l at baselines, respectively. Statin use was associated with a reduced risk of APTC events, CV mortality or all-cause mortality in PP {adjusted hazard ratio (HR), 0.65 [95% confidence interval (CI) 0.48-0.88]; 0.73 (95% CI 0.52-0.98); 0.59 (95% CI 0.48-0.73)} and SP [adjusted HR, 0.66 (95% CI 0.52-0.84); 0.60 (95% CI 0.47-0.77); 0.56 (95% CI 0.47-0.68)], respectively.

CONCLUSION

Statin use reduced TC concentrations by ∼13% in patients with CKD. Statins were protective of APTC events, CV mortality and all-cause mortality in patients with or without established CV disease.

Role of Growth Hormone Deficiency and Treatment in Chronic Kidney Disease

Malnutrition and inflammation are strong predictors of mortality in advanced kidney disease, especially in patients on renal replacement therapy. The complex relationship between kidney disease, uremia, and malnutrition significantly contributes to the increased morbidity and mortality in this patient population potentially through a relative deficiency in growth hormone (GH). With an approximate 26 million Americans currently affected by some stage of chronic kidney disease and a predicted 750,000 people to be on dialysis by 2020, there is a need to develop innovative strategies aimed at reducing the high mortality seen in dialysis patients. We will review evidence on one such intervention with infusion of recombinant GH to improve the nutritional and inflammatory state, thereby expecting to improve the mortality and morbidity in this patient population.

Evidence-based statin prescription for cardiovascular protection in renal impairment

Dyslipidemia is a well-known risk factor for cardiovascular disease in the general population, and the cardioprotective role of statins is well established. However, although cardiovascular disease is the major cause of morbidity and mortality in chronic kidney disease (CKD), the role of statin therapy is still under investigation. In CKD the atherosclerotic burden is high and pathophysiology of dyslipidemia is complex; however, the majority of large-scale statin trials excluded patients with CKD. Statins could have different effects in the different stages of CKD. Two large trials involving haemodialysis patients showed unfavourable results, whereas in renal transplant subjects as well as in early CKD subjects, statins reduced cardiovascular risk. The studies involving early CKD patients are post-hoc analyses of large trials and they showed that statins are more effective in secondary than in primary prevention. The aim of this study was to evaluate the effectiveness of statins for prevention of cardiovascular events by calculating the number of patients needed to be treated in different interventional trials. We conclude that dyslipidemia is a modifiable cardiovascular risk and statins appear to be an effective treatment especially in the early stages of CKD. Patients on renal replacement therapy could obtain an advantage from this treatment; however, the patient's clinical prognosis should be taken into account when evaluating treatment.

Statins and renal disease: friend or foe?

The role of statins in the treatment and prevention of cardiovascular diseases, such as coronary artery disease, acute coronary syndromes, diabetes, or stroke, is well established. However, there are still some questions regarding the role of statins in patients with chronic kidney disease (CKD). Dyslipidemia is a known cardiovascular risk factor in individuals without CKD. In these patients, however, the relation of dyslipidemia to cardiovascular risk is complex, and the underlying pathobiological mechanisms are complex. Statins have proven to be highly effective in patients with initial stages of CKD; however, their effects in patients with advanced-stage CKD have been neutral despite a low-density lipoprotein cholesterol-lowering effect. In this review, we summarize the findings of the recent clinical trials of statins in renal disease and make recommendations for our patients.