Non-high-density lipoprotein cholesterol (non-HDL-C) as a predictor of cardiovascular mortality in patients with end-stage renal disease

Sex-specific associations between serum lipids and hemostatic factors: the cross-sectional population-based KORA-fit study

BACKGROUND

Studies on the associations between lipid parameters and different hemostatic factors in men and women from the general population are scarce. It was therefore examined whether there are possible relationships between routinely measured serum lipids (total cholesterol, HDL-cholesterol, non-HDL-cholesterol, LDL-cholesterol, and triglycerides) and different hemostatic factors (activated partial thromboplastin time (aPTT), fibrinogen, factor VIII, antithrombin III (AT III), protein C, protein S, and D-dimer).

METHODS

The analysis was based on data from the Cooperative Health Research in the Region of Augsburg (KORA)-Fit study, which included 805 participants (378 men, 427 women) with a mean age of 63.1 years. Sex-specific associations between serum lipids and coagulation factors were investigated using multivariable linear regression models.

RESULTS

In men, total cholesterol was inversely related to aPTT but positively associated with protein C activity. HDL cholesterol was inversely related to aPTT and fibrinogen. LDL cholesterol, non-HDL cholesterol, and triglycerides showed a positive association with protein C and protein S activity. In women, LDL-cholesterol, total cholesterol, and non-HDL-cholesterol were positively related to AT III concentrations and protein C and S activity. Additionally, non-HDL-cholesterol was positively associated with factor VIII activity. HDL cholesterol was inversely related to fibrinogen. Triglycerides showed a positive relationship with protein C activity.

CONCLUSIONS

There seem to be sex differences regarding various associations between blood lipid levels and hemostatic factors. Further studies are needed to address the possible impact of these associations on cardiovascular risk and the underlying mechanisms.

Inflammation and Cardiovascular Disease Associated With Hemodialysis for End-Stage Renal Disease

Chronic kidney disease (CKD) and cardiac insufficiency often co-exist, particularly in uremic patients on hemodialysis (HD). The occurrence of abnormal renal function in patients with cardiac insufficiency is often indicative of a poor prognosis. It has long been established that in patients with cardiac insufficiency, poorer renal function tends to indicate poorer cardiac mechanics, including left atrial reserve strain, left ventricular longitudinal strain, and right ventricular free wall strain (Unger et al., Eur J Heart Fail, 2016, 18(1), 103–12). Similarly, patients with chronic kidney disease, particularly uremic patients on HD, often have cardiovascular complications in addition to abnormal endothelial function with volume overload, persistent inflammatory states, calcium overload, and imbalances in redox responses. Cardiac insufficiency due to uremia is therefore mainly due to multifaceted non-specific pathological changes rather than pure renal insufficiency. Several studies have shown that the risk of adverse cardiovascular events is greatly increased and persistent in all patients treated with HD, especially in those who have just started HD treatment. Inflammation, as an important intersection between CKD and cardiovascular disease, is involved in the development of cardiovascular complications in patients with CKD and is indicative of prognosis (Chan et al., Eur Heart J, 2021, 42(13), 1244–1253). Therefore, only by understanding the mechanisms underlying the sequential development of inflammation in CKD patients and breaking the vicious circle between inflammation-mediated renal and cardiac insufficiency is it possible to improve the prognosis of patients with end-stage renal disease (ESRD). This review highlights the mechanisms of inflammation and the oxidative stress that co-exists with inflammation in uremic patients on dialysis, as well as the mechanisms of cardiovascular complications in the inflammatory state, and provides clinical recommendations for the anti-inflammatory treatment of cardiovascular complications in such patients.

The U-Shaped Association of Non-High-Density Lipoprotein Cholesterol Levels With All-Cause and Cardiovascular Mortality Among Patients With Hypertension

Background: Non-high-density lipoprotein cholesterol (non-HDL-C) is a valuable indicator in routine blood lipid tests, but the associations of non-HDL-C with mortality in hypertensive population still remain uncertain.

Methods: In the National Health and Nutrition Examination Surveys from 1999 to 2014, participants having hypertension were included and grouped by non-HDL-C levels (<130, 130–159, 160–189, 190–219, and ≥220 mg/dl). Multivariate Cox regression was conducted for calculation of hazard ratios (HR) and 95% confidence interval (CI). To reveal the relationship between non-HDL-C and mortality, Kaplan–Meier survival curves, restricted cubic spline, linear regression, and subgroup analysis were also applied.

Results: A total of 12,169 participants (47.52% males, mean age 57.27 ± 15.79 years) were included. During average follow-up of 92.5 months, 1,946 (15.99%) all-cause deaths and 422 (3.47%) cardiovascular deaths occurred. After adjusting for confounders, the association of non-HDL-C with mortality was detected as U-shaped. Threshold values were observed at 158 mg/dl for all-cause mortality and 190 mg/dl as to cardiovascular mortality. Below the threshold, every 10 mg/dl increment in non-HDL-C attributed to relatively low all-cause mortality significantly (HR = 0.94, 95% CI: 0.92–0.96). Above the threshold, non-HDL-C has significant positive associations with both all-cause (HR = 1.03, 95% CI: 1.01–1.05) and cardiovascular mortality (HR = 1.09, 95% CI: 1.05–1.14). For subgroups analysis, similar results were found among participants age <65 years old, non-white population, those were not taking lipid-lowering drugs, and subjects with body mass index (BMI) ≥25 kg/m².

Conclusion: The U-shaped association was detected between non-HDL-C and mortality among hypertensive population.

Non-high-density lipoprotein cholesterol and mortality among peritoneal dialysis patients

BACKGROUND

The association between non-high-density lipoprotein cholesterol (non-HDL-C) and mortality in patients undergoing peritoneal dialysis (PD) is unclear.

OBJECTIVE

The aim of this study was to evaluate the association of non-HDL-C with cardiovascular (CV) and all-cause mortality in PD patients.

METHODS

We conducted a prospective cohort study. A total of 1,616 incident PD patients from a single PD center in South China were followed for a median of 47.6 months. The independent association of non-HDL-C with CV and all-cause mortality was evaluated by a Cox regression analysis.

RESULTS

During the follow-up period, 508 (31.4%) patients died, of which 249 (49.0%) were due to CV events. Atherosclerotic CV mortality accounted for 59.8% of CV mortality. In multivariable models, for 1-SD increase in non-HDL-C level, the hazard ratios (HRs) for CV and all-cause mortality were 1.52  [95% confidence interval (CI), 1.32-1.75; P < 0.001)] and 1.24 (95% CI, 1.12-1.39; P < 0.001), respectively. Furthermore, non-HDL-C was positively associated with atherosclerotic CV mortality (HR, 1.29; 95% CI, 1.09-1.52; P = 0.004) but not associated with nonatherosclerotic CV mortality (HR, 0.79; 95% CI, 0.59-1.05; P = 0.108). The quartile analyses showed a similar pattern to the continuous variable analyses of non-HDL-C levels for CV and all-cause mortality but did not demonstrate statistical significance for atherosclerotic or nonatherosclerotic CV mortality.

CONCLUSION

An elevated non-HDL-C level was independently associated with an increased risk of CV mortality, especially atherosclerotic CV mortality, and all-cause mortality in incident PD patients.

Efficacy of Oral Administration of Allium sativum Powder "Garlic Extract" on Lipid Profile, Inflammation, and Cardiovascular Indices among Hemodialysis Patients

Background

Inflammation plays a prominent role in the deteriorating cardiovascular risk of hemodialysis patients. Utilization of herbal remedies, especially garlic extract, in these patients has resulted in promising improvement in lipid profile, inflammation, and cardiovascular markers.

Purpose

In this survey, we aimed to determine the effects of oral administration of Allium sativum powder on lipid profile, inflammation, and cardiovascular markers among hemodialysis patients.

Methods

In this interventional double-blinded randomized crossover study, 70 patients were enrolled and assigned in two groups. Each group received 300 mg of garlic powder BID or placebo for eight weeks; after a six-week wash-out period, the agents were switched between two groups so that the group who received garlic powder in the first eight weeks received placebo for the second eight weeks, and vice versa. Venous blood samples were obtained in baseline, wash-out period, and at the end of study. Following obtaining laboratory data, BUN, creatinine, Na, K, Ca, Ph, homocysteine, and lipid profile were compared.

Results

No significant differences were shown at baselines of outcomes between the garlic and placebo group (p value>0.05). However, there was a significant decrease in absolute values of OXLDL (mean placebo = 979.63, mean garlic = 676.54; p value<0.001) and HCY (mean placebo = 36.54, mean garlic = 27.78; p value<0.001). In addition, significant treatment differences were seen in change values of Ca (placebo = 1.17, garlic = 0.21; p value = 0.006), TG (placebo = −6.71, garlic = -24.14; p value = 0.014), OXLDL (placebo = −281.30, garlic = -699.78; p value<0.001), and HCY (placebo = −0.24, garlic = −6.68; p value<0.001).

Conclusion

In this study, Allium sativum powder demonstrated efficacy in lipid profile improvement and renal protective effects among hemodialysis patients.

Statins for Treatment of Dyslipidemia in Chronic Kidney Disease

Dyslipidemia is a potent cardiovascular (CV) risk factor in the general population. Elevated low-density lipoprotein cholesterol (LDL-C) and/or low high-density lipoprotein (HDL-C) are well-established CV risk factors, but more precise determinants of risk include increased apoprotein B (ApoB), lipoprotein(a) [Lp(a)], intermediate and very low-density lipoprotein (IDL-C, VLDL-C; “remnant particles”), and small dense LDL particles. Lipoprotein metabolism is altered in association with declining glomerular filtration rate such that patients with non dialysis-dependent chronic kidney disease (CKD) have lower levels of HDL-C, higher triglyceride, ApoB, remnant IDL-C, remnant VLDL-C, and Lp(a), and a greater proportion of oxidized LDL-C. Similar abnormalities are prevalent in hemodialysis (HD) patients, who often manifest proatherogenic changes in LDL-C in the absence of increased levels. Patients treated with peritoneal dialysis (PD) have a similar but more severe dyslipidemia compared to HD patients due to stimulation of hepatic lipoprotein synthesis by glucose absorption from dialysate, increased insulin levels, and selective protein loss in the dialysate analogous to the nephrotic syndrome. In the dialysis-dependent CKD population, total cholesterol is directly associated with increased mortality after controlling for the presence of malnutrition–inflammation.

Treatment with statins reduces CV mortality in the general population by approximately one third, irrespective of baseline LDL-C or prior CV events. Statins have similar, if not greater, efficacy in altering the lipid profile in patients with dialysis-dependent CKD (HD and PD) compared to those with normal renal function, and are well tolerated in CKD patients at moderate doses (≤ 20 mg/day atorvastatin or simvastatin). Statins reduce C-reactive protein as well as lipid moieties such as ApoB, remnants IDL and VLDL-C, and oxidized and small dense LDL-C fraction. Large observational studies demonstrate that statin treatment is independently associated with a 30% – 50% mortality reduction in patients with dialysis-dependent CKD (similar between HD- and PD-treated patients). One recent randomized controlled trial evaluated the ability of statin treatment to reduce mortality in type II diabetics treated with HD (“4D”); the primary end point of death from cardiac cause, myocardial infarction, and stroke was not significantly reduced. However, results of this trial may not apply to other end-stage renal disease populations. Two ongoing randomized controlled trials (SHARP and AURORA) are underway evaluating the effect of statins on CV events and death in patients with CKD (including patients treated with HD and PD). Recruitment to future trials should be given a high priority by nephrologists and, until more data are available, consideration should be given to following published guidelines for the treatment of dyslipidemia in CKD. Additional consideration could be given to treating all dialysis patients felt to be at risk of CV disease (irrespective of cholesterol level), given the safety and potential efficacy of statins. This is especially relevant in patients treated with PD, given their more atherogenic lipid profile and the lack of randomized controlled trials in this population.

Higher Cholesterol Level Predicts Cardiovascular Event and Inversely Associates With Mortality in Hemodialysis Patients: 10-Year Outcomes of the Q-Cohort Study

The prevalence of atherosclerotic diseases is higher in hemodialysis patients. The aim of the current study was to investigate associations between cholesterol level and the incidences of cardiovascular disease (CVD) and mortality in hemodialysis patients. A total of 3517 participants undergoing maintenance hemodialysis were followed up for 10 years. Total cholesterol (TC) level was divided into quartile in baseline data. The multivariate analyses were calculated by a Cox proportional hazards model. The incidences of ischemic heart disease (IHD), peripheral artery disease (PAD), and CVD were significantly positively associated with higher cholesterol levels after adjustment for confounding factors (P < 0.01, P = 0.04, and P < 0.01, respectively). Furthermore, the incidences of cancer-associated mortality and all-cause mortality were significantly positively associated with lower cholesterol levels after adjustment for confounding factors (both P < 0.01). The lowest TC level at all-cause mortality risk was 179 mg/dL. From these results, higher TC predicts IHD, PAD, and CVD events, and lower TC predicts cancer-associated mortality and all-cause mortality in patients undergoing maintenance hemodialysis.

Appropriate Total cholesterol cut-offs for detection of abnormal LDL cholesterol and non-HDL cholesterol among low cardiovascular risk population

BACKGROUND

Current guidelines suggest screening for dyslipidemia in early adulthood. In Thailand, a screening total cholesterol level is most commonly used potentially due to the costs of the test. However, the appropriate TC cut-off point that correlates with elevated low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (Non-HDL-C) levels for the low cardiovascular risk younger population have not been examined extensively in the literature.

METHODS

This study identified 1754 subjects with low cardiovascular risk. All participants had a physical examination and a venous blood sample sent for laboratory assessment of fasting blood glucose, TC, LDL-C, HDL-C levels. A non-HDL-C level for everyone was calculated by subtracting HDL-C levels from their total cholesterol levels. Sensitivity and specificity of different TC cutoff points in detection of abnormal LDL-C levels (≥ 130 mg/dL and ≥ 160 mg/dL) and abnormal non-HDL-C levels (≥ 160 mg/dL and ≥ 190 mg/dL) were calculated. Receiver operating characteristics (ROC) curve analysis was used to evaluate the predictive utility of TC for the abnormal LDL-C and abnormal non-HDL-C levels.

RESULTS

The conventional range TC cut off point, between 200 to 240, had varying diagnostic properties for detection of elevated LDL-C and Non-HDL-C within this low risk population. A TC cut off point 210 would have a sensitivity of 70% and specificity of 92.5% for detection of LDL-C ≥ 130 and a sensitivity of 96.7% and specificity of 85.6% for identifying those with Non-HDL-C ≥ 160. The TC cut off point of 230 had a sensitivity of 74.9% and specificity of 92.0% in identifying those with LDL-C ≥ 160 and a sensitivity of 98.6% and specificity of 89.8% in detection of non-HDL-C ≥ 190.

CONCLUSIONS

Early screening for dyslipidemia in young adults is suggested by many guidelines. This population is likely to be those with lower cardiovascular risk and may needed to have repeated screening over time. Screening using TC with appropriate a cut off points may be a more cost-effective screening test in settings with limited resources, coverage and accessibility.

Inverse Association Between Serum Non-High-Density Lipoprotein Cholesterol Levels and Mortality in Patients Undergoing Incident Hemodialysis

Background

There is accumulating evidence that serum levels of non–high‐density lipoprotein cholesterol (non–HDL‐C) are a more accurate predictor of cardiovascular outcomes when compared with low‐density lipoprotein cholesterol. However, we recently found that higher serum concentrations of triglycerides are associated with better outcomes in patients undergoing hemodialysis. Therefore, we hypothesized that the association of serum levels of non–HDL‐C (which includes triglyceride‐rich lipoproteins) with outcomes may also be different in patients undergoing hemodialysis when compared with other patient populations.

Methods and Results

We studied the association of baseline and time‐dependent serum levels of non–HDL‐C with all‐cause and cardiovascular mortality using Cox proportional hazard regression models in a nationally representative cohort of 50 118 patients undergoing incident hemodialysis from January 1, 2007, to December 31, 2011. In time‐dependent models adjusted for case mix and surrogates of malnutrition and inflammation, a graded inverse association between non–HDL‐C level and mortality was demonstrated with hazard ratios (95% confidence intervals) of the lowest (<60 mg/dL) and highest (≥160 mg/dL) categories: 1.88 (1.72–2.06) and 0.73 (0.64–0.83) for all‐cause mortality and 2.07 (1.78–2.41) and 0.75 (0.60–0.93) for cardiovascular mortality, respectively (reference, 100–115 mg/dL). In analyses using baseline values, non–HDL‐C levels <100 mg/dL were also associated with significantly higher mortality risk across all levels of adjustment. Similar associations were found when evaluating non‐HDL/HDL cholesterol ratio and mortality, with the highest all‐cause and cardiovascular mortality being observed in patients with decreased non‐HDL/HDL‐C ratio (<2.5).

Conclusions

Contrary to the general population, decrements in non–HDL‐C and non‐HDL/HDL cholesterol ratio were paradoxically associated with increased all‐cause and cardiovascular mortality in patients undergoing incident hemodialysis. The underlying mechanisms responsible for these associations await further investigation.

Obesity and the risk of cardiovascular and all-cause mortality in chronic kidney disease: a systematic review and meta-analysis

Background

Obesity is a risk factor for cardiovascular disease and death in people without chronic kidney disease (CKD), but the effect of obesity in people with CKD is uncertain.

Methods

Medline and Embase (from inception to January 2015) were searched for cohort studies measuring obesity by body mass index (BMI), waist:hip ratio (WHR) and/or waist circumference (WC) and all-cause and cardiovascular mortality or events in patients with any stage of CKD. Data were summarized using random effects models. Meta-regression was conducted to assess sources of heterogeneity.

Results

Of 4065 potentially eligible citations, 165 studies ( n = 1 534 845 participants) were analyzed. In studies that found a nonlinear relationship, underweight people with CKD (3-5) on hemodialysis experienced an increased risk of death compared with those with normal weight. In transplant recipients, excess risk was observed at levels of morbid obesity (>35 kg/m 2 ). Of studies that found the relationship to be linear, a 1 kg/m 2 increase in BMI was associated with a 3 and 4% reduction in all-cause and cardiovascular mortality in patients on hemodialysis, respectively {adjusted hazard ratio [HR] 0.97 [95% confidence interval (CI) 0.96-0.98] and adjusted HR 0.96 (95% CI 0.92-1.00)}. In CKD Stages 3-5, for every 1 kg/m 2 increase in BMI there was a 1% reduction in all-cause mortality [HR 0.99 (95% CI 0.0.97-1.00)]. There was no apparent association between obesity and mortality in transplanted patients or those on peritoneal dialysis. Sparse data for WHR and WC did not allow further analyses.

Conclusions

Being obese may be protective for all-cause mortality in the predialysis and hemodialysis populations, while being underweight suggests increased risk, but not in transplant recipients.

Serum Non-High-Density Lipoprotein Cholesterol and Risk of Cardiovascular Disease in Community Dwellers with Chronic Kidney Disease: the Hisayama Study

AIM

It is not clear whether elevated serum non-high-density lipoprotein cholesterol (non-HDL-C) levels are a risk factor for cardiovascular disease (CVD) in subjects with chronic kidney disease (CKD) in the general population.

METHODS

A total of 2,630 community-dwelling Japanese subjects (1,107 men and 1,523 women) without history of CVD and aged ≥40 years were prospectively followed up for an average of 19 years, and the association between serum non-HDL-C levels and the incidence of type-specific CVD was estimated using a Cox proportional hazards model. CKD was defined as estimated glomerular filtration rate ＜60 mL/min/1.73 m2 or proteinuria (≥1＋ on dipstick).

RESULTS

At baseline, 357 subjects had CKD. During the follow up, 186 coronary heart disease (CHD) and 277 stroke events occurred. The age- and sex-adjusted incidence of CHD was significantly higher in subjects with higher non-HDL-C levels, both in those with and without CKD. In the CKD group, the risk of CHD was significantly higher in those with non-HDL-C levels of 150- 189 mg/dL [adjusted hazard ratio (HR), 2.23; 95% confidence interval (CI), 1.04-4.77] and those with levels ≥190 mg/dL (adjusted HR, 3.20; 95% CI, 1.46-7.03) than in those with levels ＜150 mg/dL. In the non-CKD group, the risk of CHD was significantly higher only in those with nonHDL-C levels ≥190 mg/dL (adjusted HR, 2.12; 95% CI, 1.33-3.38). However, no such association was observed for the risk of stroke.

CONCLUSIONS

Our findings suggest that higher serum non-HDL-C levels are associated with greater risk of CHD in subjects with and without CKD and that this association is greater in subjects with CKD than in those without CKD.

Protein-energy malnutrition: a risk factor for various ailments

The wheel of industrialization that spun throughout the last century resulted in urbanization coupled with modifications in lifestyles and dietary habits. However, the communities living in developing economies are facing many problems related to their diet and health. Amongst, the prevalence of nutritional problems especially protein-energy malnutrition (PEM) and micronutrients deficiencies are the rising issues. Moreover, the immunity or susceptibility to infect-parasitic diseases is also directly linked with the nutritional status of the host. Likewise, disease-related malnutrition that includes an inflammatory component is commonly observed in clinical practice thus affecting the quality of life. The PEM is treatable but early detection is a key for its appropriate management. However, controlling the menace of PEM requires an aggressive partnership between the physician and the dietitian. This review mainly attempts to describe the pathophysiology, prevalence and consequences of PEM and aims to highlight the importance of this clinical syndrome and the recent growth in our understanding of the processes behind its development. Some management strategies/remedies to overcome PEM are also the limelight of the article. In the nutshell, early recognition, prompt management, and robust follow up are critical for best outcomes in preventing and treating PEM.

Triglyceride to high-density lipoprotein cholesterol ratio predicts cardiovascular outcomes in prevalent dialysis patients

Triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, an indicator of atherogenic dyslipidemia, is a predictor of cardiovascular (CV) outcomes in the general population and has been correlated with atherosclerotic events. Whether the TG/HDL-C ratio can predict CV outcomes and survival in dialysis patients is unknown. We performed this prospective, observational cohort study and enrolled 602 dialysis patients (539 hemodialysis and 63 peritoneal dialysis) from a single center in Taiwan followed up for a median of 3.9 years. The outcomes were the occurrence of CV events, CV death, and all-cause mortality during follow-up. The association of baseline TG/HDL-C ratio with outcomes was explored with Cox regression models, which were adjusted for demographic parameters and inflammatory/nutritional markers. Overall, 203 of the patients experienced CV events and 169 patients died, of whom 104 died due to CV events. Two hundred fifty-four patients reached the composite CV outcome. Patients with higher TG/HDL-C levels (quintile 5) had a higher incidence of CV events (adjusted hazard ratio [HR] 2.03, 95% confidence interval [CI] 1.19-3.47), CV mortality (adjusted HR 1.91, 95% CI 1.07-3.99), composite CV outcome (adjusted HR 2.2, 95% CI 1.37-3.55), and all-cause mortality (adjusted HR 1.94, 95% CI 1.1-3.39) compared with the patients in quintile 1. However, in diabetic dialysis patients, the TG/HDL-C ratio did not predict the outcomes. The TG/HDL-C ratio is a reliable and easily accessible predictor to evaluate CV outcomes and survival in prevalent nondiabetic dialysis patients. ClinicalTrials.gov: NCT01457625.

Dyslipidemia, malnutrition, inflammation, cardiovascular disease and mortality in chronic kidney disease

PURPOSE OF REVIEW

Dyslipidemia, malnutrition and inflammation are common in patients with chronic kidney disease (CKD) and are strongly associated with cardiovascular disease (CVD) and increased mortality. The epidemiology of dyslipidemia and its interactions with malnutrition and inflammation in CKD patients have been the subject of much interest in the past decade. Recent clinical trials have explored the effects of statins on CVD specifically in CKD patients.

RECENT FINDINGS

Whereas the risk relationship between total cholesterol level and CVD morbidity and mortality is direct, strong and progressive in CKD patients without malnutrition and inflammation, it is inconsistent and often paradoxical in those with malnutrition and inflammation. Accumulating evidence demonstrates that statins reduce significantly the risk of CVD in CKD patients before the initiation of dialysis. However, the beneficial effect of statins in CKD patients on dialysis is uncertain. In CKD patients on dialysis, malnutrition and inflammation pose a higher risk for CVD than dyslipidemia.

SUMMARY

In CKD patients, the risk of CVD associated to dyslipidemia is complex and is modified by malnutrition and inflammation.

Insulin resistance as a predictor of cardiovascular disease in patients on peritoneal dialysis

BACKGROUND

Insulin resistance is associated with multiple risk factors for cardiovascular (CV) disease in the general population. Patients on peritoneal dialysis (PD) are more likely to develop insulin resistance. However, no evaluation of the impact of insulin resistance on CV disease morbidity or mortality in patients on PD has been performed.

METHODS

Our prospective cohort study included all non-diabetic patients on PD at our center (n = 66). Insulin resistance was evaluated at baseline by the homeostasis model assessment method (HOMA-IR) using fasting glucose and insulin levels. The cohort was followed for up to 58 months (median: 41.3 months; interquartile range: 34.3 months). A multivariate Cox model was used to analyze the impact of insulin resistance on CV disease mortality.

RESULTS

Fourteen CV events occurred in the higher HOMA-IR group [IR-H (HOMA-IR values in the range 2.85 - 19.5), n = 33], but only one event occurred in the lower HOMA-IR group (IR-L (HOMA-IR values in the range 0.83 - 2.71), n = 33) during the follow-up period. Level of HOMA-IR was a significant predictor of CV events [risk ratio: 17.7; 95% confidence interval (CI): 2.10 to 149.5; p = 0.008]. In the IR-H group, 10 patients died (8 CV events), but in the IR-L group, only 4 patients died (1 CV event). Patients in the IR-H group experienced significantly higher CV mortality (hazard ratio: 9.02; 95% CI: 1.13 to 72.2; p = 0.04). Even after adjustments for age, systolic blood pressure, body mass index, C-reactive protein, triglycerides, resistin, and leptin, HOMA-IR remained an independent predictor of CV mortality (hazard ratio: 14.8; 95% CI: 1.22 to 179.1; p = 0.03).

CONCLUSIONS

Insulin resistance assessed using HOMA-IR was an independent predictor of CV morbidity and mortality in a cohort of nondiabetic patients on PD. Insulin resistance is a modifiable risk factor; the reduction of insulin resistance may reduce CV risk and improve survival in this group of patients.

Prevalence and progression of cardiovascular calcifications in peritoneal dialysis patients: A prospective study

BACKGROUND

Patients on dialysis may have abnormal serum levels of Ca, P and parathyroid hormone, with related bone diseases. This population has an increased risk of death, with cardiovascular calcification (CC) a contributing factor. Patients on peritoneal dialysis appear to be at increased risk of hyperlipidemia, a contributing factor to atherosclerotic plaque formation. Although several studies have described the presence and progression of CC in hemodialysis populations, there are fewer data in patients on peritoneal dialysis.

STUDY DESIGN

The Renal Osteodystrophy and Calcifications: Key factors in Peritoneal Dialysis (ROCK-PD) study was a 36-month, prospective observational study conducted in Italy. The study examined the presence and progression of CC in two cardiac valves and five arterial sites. The potential associations of serum Ca and P with mortality and cardiovascular morbidity, demographic, clinical and blood chemistry variables was investigated.

RESULTS

CC was present in 77% of patients at baseline (N=369) and in 90% of patients by study end (N=145), progressing in 73% of patients. There were 42 deaths (11%). Analyses showed a marked correlation between baseline P levels and the presence of left ventricular hypertrophy. However, there were no consistent correlations between serum Ca or P with mortality or morbidity.

CONCLUSIONS

CC was common in peritoneal dialysis patients and progressed in a majority of patients.

Non-high-density lipoprotein cholesterol: an important predictor of stroke and diabetes-related mortality in Japanese elderly diabetic patients

AIMS

To evaluate the association of low-density lipoprotein, high-density lipoprotein and non-high-density lipoprotein cholesterol with the risk of stroke, diabetes-related vascular events and mortality in elderly diabetes patients.

METHODS

This study was carried out as a post-hoc landmark analysis of a randomized, controlled, multicenter, prospective intervention trial. We included 1173 elderly type 2 diabetes patients (aged ≥ 65 years) from 39 Japanese institutions who were enrolled in the Japanese elderly diabetes intervention trial study and who could be followed up for 1 year. A landmark survival analysis was carried out in which follow up was set to start 1 year after the initial time of entry.

RESULTS

During 6 years of follow up, there were 38 cardiovascular events, 50 strokes, 21 diabetes-related deaths and 113 diabetes-related events. High low-density lipoprotein cholesterol was associated with incident cardiovascular events, and high glycated hemoglobin was associated with strokes. After adjustment for possible covariables, non-high-density lipoprotein cholesterol showed a significant association with increased risk of stroke, diabetes-related mortality and total events. The adjusted hazard ratios (95% confidence intervals) of non-high-density lipoprotein cholesterol were 1.010 (1.001-1.018, P = 0.029) for stroke, 1.019 (1.007-1.031, P < 0.001) for diabetes-related death and 1.008 (1.002-1.014; P < 0.001) for total diabetes-related events.

CONCLUSIONS

Higher non-high-density lipoprotein cholesterol was associated with an increased risk of stroke, diabetes-related mortality and total events in elderly diabetes patients.

Clinical factors associated with serum copper levels and potential effect of sevelamer in hemodialysis patients

OBJECTIVE

Copper is an essential mineral nutrient for humans. Serum copper levels of hemodialysis patients are higher than those of healthy subjects, but it remains to be elucidated whether increased serum copper may have harmful effects. In addition, a recent in vitro study has shown that sevelamer can adsorb copper. In the present study, we searched for clinical factors associated with serum copper levels in hemodialysis patients.

METHODS

This cross-sectional study included patients undergoing hemodialysis for more than 6 months. In these patients, we statistically tested associations between serum copper levels and other parameters, including nutritional markers, lipid profiles, oxidative stress, inflammation, and sevelamer administration.

RESULTS

Among 48 patients (male/female = 28:20, age 71 ± 10 years, hemodialysis duration 84 ± 72 months), sevelamer hydrochloride was administered in 39 patients (81.3 %). In univariate analysis, serum copper levels showed significant positive correlations with serum levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, high-sensitivity C-reactive protein (hs-CRP), and malondialdehyde modified-LDL and negative correlations with plasma total homocysteine levels and the administered dose of sevelamer. In multivariate analysis, serum levels of LDL-cholesterol and hs-CRP were found to be independent determinants of serum copper levels.

CONCLUSION

We found that serum copper levels were independently associated with dyslipidemia and inflammation in hemodialysis patients, but the pathogenic roles of copper remain to be elucidated. In addition, potential effect of sevelamer on serum copper levels should be examined in appropriately designed studies.

Serum non-high-density lipoprotein cholesterol (non-HDL-C) levels and cardiovascular mortality in chronic hemodialysis patients

BACKGROUND

Non-high-density lipoprotein cholesterol (non-HDL-C) has been proposed as a predictor of cardiovascular disease (CVD) in the general population. The aim of this study was to evaluate the utility of non-HDL-C in predicting CV mortality in chronic hemodialysis (HD) patients.

METHODS

We calculated the serum non-HDL-C level of 259 HD patients by subtracting their HDL-C levels from their total cholesterol. Cox proportional hazards models were used to estimate the hazards ratio (HR) for CV mortality and the 95% confidence interval (CI). A receiver-operating characteristic (ROC) analysis was performed to estimate the relationship between sensitivity and specificity of a diagnostic parameter.

RESULTS

There were 44 deaths (17.0%) during the follow-up period, 33 (12.7%) of which were due to CVD. A multivariate Cox analysis with adjustments for age, diabetes, dialysis vintage, systolic blood pressure, serum albumin, and lipid levels showed that non-HDL-C was an independent predictor of CV mortality (HR 1.015, 95% CI 1.004-1.025, p = 0.0083). An ROC analysis showed that the plots of the non-HDL-C levels yielded significant specificity and sensitivity for predicting the risk of CVD mortality in HD patients [area under the curve (AUC) 0.62416; p = 0.0366; cutoff value 111.0 mg/dl]. The Kaplan-Meier survival curves of HD patients showed significant differences in CV mortality according to their tertiles with respect to serum non-HDL-C levels (p = 0.0165).

CONCLUSION

The results of this study suggest that serum non-HDL-C level is a significant CV mortality predictor of chronic HD patients.

Non-high-density lipoprotein cholesterol and its correlation with anthropometric markers of cardiovascular risk in hemodialysis

INTRODUCTION

Non-high-density lipoprotein cholesterol (non-HDL-c) may be a better indicator of atherogenicity in the hemodialysis population.

PURPOSE

To investigate the correlation of non-HDL-c with anthropometric measurements associated to cardiovascular risk, such as body mass index, waist circumference, waist-to-height ratio, waist-to-height(2) ratio, and waist-to-hip circumference ratio.

METHODS

We evaluated anthropometric markers and lipids in 86 hemodialysis patients, and the correlation between them was investigated.

RESULTS

Non-HDL-c had a positive correlation with body mass index (r = 0.273; P = .01), waist circumference (r = 0.375; P = .000), waist-to-height ratio (r = 0.333; P = .002), waist-to-height(2) ratio (r = 0.270; P = .012), and waist-to-hip circumference ratio (r = 0.356; P = .001).

CONCLUSIONS

This study detected a positive and significant correlation between non-HDL-c, but not low-density lipoprotein cholesterol, and the anthropometric cardiovascular risk indexes. We could suggest that non-HDL-c can be used as a cardiovascular risk factor indicator among dialysis patients.

Glucose concentration in the dialysate does not contribute to lipid profiles in patients undergoing CAPD

The aim of this study was to investigate lipid profiles in patients with end-stage renal disease receiving hemodialysis (HD), continuous ambulatory peritoneal dialysis (CAPD), or no dialysis (nondialytic treatment group, NT), and to analyze the association between dyslipidemia in CAPD patients with glucose-containing dialysate dosages. Lipid profiles were determined in 64 NT patients, 62 HD patients, and 180 CAPD patients at a single time point. NT patients' samples were collected following hospitalization due to renal failure. HD and CAPD patients' samples were collected after 3 months of dialysis. The association between lipid profiles of 180 CAPD patients and glucose-containing dialysate was analyzed using Pearson methods; 76.56% of NT patients, 66.13% of HD patients, and 72.22% of CAPD patients had dyslipidemia. Compared with NT patients, CAPD patients had significantly altered levels of cholesterol, triglycerides, high-density lipoprotein, apolipoproein (Apo)-A1, and Apo-E (p < 0.05), but unchanged levels of low-density lipoprotein or Apo-B. There was no correlation between the three different concentrations of glucose in the dialysate with the lipid profile of CAPD patients. We concluded that patients on CAPD exhibit dyslipidemia, and that different concentrations of glucose in the dialysate do not affect lipid profiles in these patients.

Analysis of the correlation between non-high density lipoprotein cholesterol and coronary heart disease in elderly Chinese

OBJECTIVE

In the aged population, serum cholesterol is directly correlated with coronary heart disease (CHD) risk. We aimed to investigate the correlation between non-high density lipoprotein cholesterol (non-HDL-C) level and CHD and coronary lesions in an aged population.

METHODS

1,272 cases of old patients who were more than 65 years old and accepted for coronary angiography were analyzed retrospectively. Based on the result of coronary angiography, the patients were divided into control group and CHD group. Further, 767 CHD patients were divided into subgroups according to the number of branches with pathological changes and Gensini score. Serum TC, HDL-C, LDL-C and TG were assayed to measure the level of non-HDL-C. The differences in non-HDL-C among groups were compared, and the correlation between non-HDL-C and coronary artery disease degree was also analyzed.

RESULTS

The non-HDL-C level in the CHD group was significantly higher than that in the control group (p < 0.01). Further, the serum non-HDL-C showed an increasing tendency accompanied by the increase in branches with lesions. Compared with patients with single or double coronary artery branches lesions, the non-HDL-C in those with multiple lesions in branches was significantly increased (p < 0.01, p < 0.05). With the aggravation of coronary artery stenosis, the serum non-HDL-C level was gradually increased. The most significant increase was observed in the group with Gensini score of more than 40. There was a significant difference between Gensini score > 40 group and Gensini score of 20-40 group and Gensini score < 20 group, respectively (p < 0.05, p < 0.01). Meanwhile, there were significant positive correlations between the serum non-HDL-C level and coronary lesions area and severity (r = 0.147, p < 0.01; r = 0.152, p < 0.01).

CONCLUSION

In conclusion, serum non-HDL-C was closely associated with development of CHD and coronary artery lesions severity.

Height constitutes an important predictor of mortality in end-stage renal disease

Aim. Height is an important determinant of augmentation index (AI) that anticipates cardiovascular prognosis. There is a scanty of the data whether short height predicts survival in patients with end-stage renal diseases, a high risk population. Methods. Fifty two hypertensive patients with type 2 diabetic nephropathy receiving hemodialysis and 52 patients with nondiabetic nephropathy were enrolled. In addition to AI estimated with radial artery tonometry, classical cardiovascular risk factors were considered. Patients were followed for 2 years to assess cardiovascular prognosis. Results. Cox hazards regression revealed that both smoking and shortness in height independently contributed to total mortality and indicated that smoking as well as the presence of left ventricular hypertrophy predicted cardiovascular mortality. Our findings implicated that high AI, the presence of diabetes, and low high-density lipoprotein cholesterol were significant contributors to cardiovascular events. Conclusions. Our findings provide new evidence that shortness in height independently contributes to total mortality in hemodialysis patients.

Malnutrition-inflammation modifies the relationship of cholesterol with cardiovascular disease

In moderate and severe CKD, the association of cholesterol with subsequent cardiovascular disease (CVD) is weak. We examined whether malnutrition or inflammation (M-I) modifies the risk relationship between cholesterol levels and CVD events in African Americans with hypertensive CKD and a GFR between 20 and 65 ml/min per 1.73 m². We stratified 990 participants by the presence or absence of M-I, defined as body mass index <23 kg/m² or C-reactive protein >10 mg/L at baseline. The primary composite outcome included cardiovascular death or first hospitalization for coronary artery disease, stroke, or congestive heart failure occurring during a median follow-up of 77 months. Baseline total cholesterol (212 ± 48 versus 212 ± 44 mg/dl) and overall incidence of the primary CVD outcome (19 versus 21%) were similar in participants with (n = 304) and without (n = 686) M-I. In adjusted analyses, the CVD composite outcome exhibited a significantly stronger relationship with total cholesterol for participants without M-I than for participants with M-I at baseline (P < 0.02). In the non-M-I group, the cholesterol-adjusted hazard ratio (HR) for CVD increased progressively across cholesterol levels: HR = 1.19 [95% CI; 0.77, 1.84] and 2.18 [1.43, 3.33] in participants with cholesterol 200 to 239 and ≥240 mg/dl, respectively (reference: cholesterol <200). In the M-I group, the corresponding HRs did not vary significantly by cholesterol level. In conclusion, the presence of M-I modifies the risk relationship between cholesterol level and CVD in African Americans with hypertensive CKD.

Lipoperoxidation and hemodialysis

It has been suggested that hemodialysis patients may be under increased oxidative stress and may therefore benefit from the long-term use of antioxidants (particularly for the reduction of the risk of heart disease). The aim of this study was, first, to evaluate the effect of hemodialysis by itself on lipid and lipoprotein oxidation profiles and, second, to analyze the effect of vitamin C supplementation in patients with end-stage renal disease starting hemodialysis. Forty-one patients with end-stage renal disease were enrolled and randomized to receive 1000 mg/d vitamin C or matching placebo before starting hemodialysis. We measured lipid profile and the susceptibility of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) to oxidation using copper ions at the moment of inclusion and after 1 year. All lipoperoxidation parameters were included. Hemodialysis by itself improved the lipid profile, lowering total cholesterol (176.4 +/- 48.4 to 154.2 +/- 28.8 mg/dL, P < .01), LDL cholesterol (94.1 +/- 39.6 to 76.1 +/- 26.6 mg/dL LDL, P < .03), and phospholipids levels (196.5 +/- 36.7 to 182.9 +/- 36.1 mg/dL, P < .05) in all patients on maintenance hemodialysis. The HDL cholesterol was also decreased (49.4 +/- 19.8 to 43.4 +/- 24.1 mg/dL HDL, P < .03). No significant differences were detected between patients receiving vitamin C and those receiving placebo. Thiobarbituric acid reactive substances (TBARS) and lipoperoxides increased in patients after a year of hemodialysis, but the difference was lower in those administered vitamin C for a year-TBARS LDL (in nanograms per gram LDL): 0.25 +/- 0.20 to 0.38 +/- 0.2 in vitamin C-treated subjects and 0.28 +/- 0.17 to 0.46 +/- 0.21 in those treated with placebo (P < .007); TBARS HDL (in nanograms per gram HDL): 0.22 +/- 0.12 to 0.34 +/- 0.30 in patients receiving vitamin C and 0.20 +/- 0.18 to 0.28 +/- 0.19 in those receiving placebo (P = .071). Hemodialysis by itself seems to improve the lipid profile in patients with a previous prooxidative state such as uremia. Although our results failed to demonstrate significant differences between vitamin C-treated and untreated patients, and despite the small number of patients, the trend toward a decrease in oxidation products due to vitamin C supplementation may be beneficial for oxidation parameters. This area remains controversial and under active investigation. Further research is necessary before a firm conclusion can be reached.

Measurement of cholesterol concentrations of major serum lipoprotein classes in haemodialysis patients by anion-exchange chromatography

BACKGROUND

Increased triglyceride (TG)-rich lipoproteins and decreased HDL that are implicated in the progression of atherosclerotic vascular diseases, are present in serum samples of patients undergoing haemodialysis (HD) therapy. Therefore, it is important to measure serum TG-rich lipoprotein concentrations to prevent the diseases.

METHODS

The cholesterol concentrations of lipoprotein classes in serum samples from the HD patients (n = 18) and healthy subjects (n = 18) were analysed by our recently developed method of high-performance liquid chromatography (HPLC), in which the lipoprotein classes were separated using an anion-exchange column, and the cholesterol concentrations of each of those were measured enzymatically using a post-column reaction. The ability of fractionated lipoprotein cholesterol determination by this HPLC method is mostly equivalent to the determination ability of an ultracentrifugation (UC).

RESULTS

HDL, LDL, and TG-rich lipoproteins, i.e. IDL, VLDL and chylomicrons, were well separated in the chromatograms. HDL cholesterol concentrations in the HD patients were significantly lower than in the healthy subjects (P < 0.0001), and IDL cholesterol concentrations and VLDL cholesterol concentrations in the HD patients were significantly higher than in the healthy subjects (P < 0.05). Profiles of these measured lipoprotein values were consistent with the previously reported lipoprotein values, measured ultracentrifugally characteristic of HD patients.

CONCLUSION

These results suggest that the HPLC method may be sufficiently applied to the assessment of serum lipoprotein profile in HD patients in place of the other method including an UC.

Misleading associations between cholesterol and vascular outcomes in dialysis patients: the need for randomized trials

Higher cholesterol is strongly associated with an increased risk of coronary heart disease (CHD) in nonrenal populations, so the lack of a clear positive association between total cholesterol and mortality among dialysis patients is unexpected. This review of prospective studies of the association between total cholesterol and mortality among dialysis patients suggests that there is a negative association at below average cholesterol levels and a flat or weakly positive association at higher levels. In nonrenal populations total cholesterol is not positively associated with vascular causes of death other than CHD, so the lack of a strongly positive association at above average cholesterol concentrations in dialysis patients may be explained by the high proportion of deaths due to non-CHD vascular causes. The observation of a negative association between total cholesterol and mortality at below average cholesterol concentrations in some studies is consistent with confounding by both vascular and nonvascular morbidity (i.e., reverse causality). We argue that evaluating the importance of cholesterol for vascular disease risk in dialysis patients can only be achieved through the eradication of confounding by randomization, and that ongoing trials of cholesterol-lowering therapy will provide a definitive answer to this question.

Lipid changes and statins in chronic renal insufficiency

It has been known for a long time that chronic kidney disease (CKD) is associated with dyslipidemia, but the full extent of abnormalities has been appreciated only recently, because routine laboratory tests fail to disclose the entire spectrum of lipid abnormalities. Lipids, particularly HDL cholesterol, are predictive of cardiovascular events, but a paradoxic inverse relation between cholesterol concentration and cardiovascular death has been noted in uremic patients. This currently is thought to be explained by the confounding effect of microinflammation and possibly calcification, but this is not definitely proved. Several retrospective analyses that included patients with mild or moderate CKD documented benefit from lowering of cholesterol by statins. In contrast, the Die Deutsche Diabetes Dialyse (4D) study and a small Scandinavian study failed to show a benefit from lowering of cholesterol by statins in ESRD. Pathomechanistically, it is possible that nonclassical pathomechanisms override statin-sensitive mechanisms as also suggested by the observation that statins fail to reduce carotid intima-media thickening. Although, experimentally, exposure to lipids (particularly oxidized lipids) aggravates progression, data on the effect of statins on progression in patients with CKD are not definite. The most likely explanation is that the impact of numerous confounders obscures their effect on progression. The increase in urinary protein excretion of patients who are treated with statins had been a cause of concern, but the underlying mechanism (i.e. interference with proximal tubular reabsorption of protein) meanwhile has been well documented.

The unique character of cardiovascular disease in chronic kidney disease and its implications for treatment with lipid-lowering drugs

Although the risk for cardiovascular disease (CVD) is high in individuals with chronic kidney disease (CKD), there are very limited data to guide the use of lipid-lowering drugs (LLDs) in this population because the major trials of LLDs in the general population have included very few individuals with CKD. The pathophysiologic and epidemiologic differences of CVD in the CKD population suggest that the study findings derived in the general population may not be directly applicable to those with CKD, and the few trials that have been directed at patients with kidney disease have not shown clear clinical benefits of LLDs. The National Kidney Foundation Kidney Disease Outcomes Quality Initiative (K/DOQI) Work Group has provided consensus-based guidelines for managing dyslipidemias in individuals with CKD and after renal transplantation. Since the publication of these statements, further data have emerged and multiple studies are ongoing to define better the role of LLDs in patients with CKD. In this article, the data that are pertinent to the CKD population are reviewed, and updated recommendations for use of LLD in the CKD population are provided.

Atherosclerotic risk factors and carotid stiffness in elderly asymptomatic HD patients

Several studies showed that carotid atherosclerosis and stiffness are independent prognostic factors of cardiovascular morbidity and mortality in the general population and in end-stage renal disease patients. However, the impact of established risk factors on carotid structural and elastic properties in non-diabetic elderly hemodialysis patients with negative history for cardiovascular disease has not been fully elucidated. In this paper, we investigated the effect of established and potential risk factors on carotid atherosclerosis and stiffness. Thirty stable, non-symptomatic, non-diabetic patients, aged 65-years and older (mean age 71.4+/-4.15, range 65-79) on hemodialysis for more than 6 months, were included. All patients underwent B-mode ultrasonography of common carotid artery estimating intima-media wall thickness and wall-to-lumen ratio bilaterally and checking for the presence of plaques. Carotid elasticity was evaluated by compliance, distensibility, and the incremental elastic modulus (Einc), whereas systemic arterial stiffening was evaluated by the augmentation index provided by tonometry of radial artery. Our results showed that presence of carotid plaques and wall thickening were frequent findings in this population (76% and 73.3%, respectively) and they were positively associated with fibrinogen (P<0.005), diastolic blood pressure (P<0.004), visceral obesity (P<0.001) and bio-intact PTH (i-PTH) (P=0.03). Overall, systemic and carotid stiffness were strongly correlated with hs-CRP (P=0.018), serum ferritin (P=0.02) with age (P=0.03), lipids (P=0.03) and i-PTH (P=0.05). In conclusion, our findings show that stiffening and atherosclerosis in non-symptomatic elderly HD patients are very common and they are related not only to hemodynamic changes (diastolic blood pressure), inflammation (hs-CRP, fibrinogen, ferritin) or metabolic dysfunction (increased i-PTH, abnormal lipid profile), but also to abnormal fat deposition (increased waist to hip ratio and waist circumference). Considering the high morbidity and mortality of elderly patients, close monitoring of these parameters could be useful to prevent cardiovascular events.

Plasma Lipoprotein Abnormalities in Hemodialysis Patients—Clinical Implications and Therapeutic Guidelines

Patients with advanced stages of chronic kidney disease (CKD) have an increased risk of death from cardiovascular disease (CVD). Dyslipidemias are associated with atherosclerotic vascular changes and the risk of occurrence of acute myocardial infarction in hemodialysis patients. However, management of dyslipidemia in hemodialysis patients does not appear to be actively carried out in routine practice. Presumably, there are three reasons for this reluctance to lipid-lowering in hemodialysis patients. First, there are epidemiological data showing the inverse relationship between cholesterol and mortality rate; a high cholesterol predicts a better survival. Second, lipids are not usually measured using standard fasting serum, but a non-fasting specimen. Third, although hypertriglyceridemia is the most common abnormality, fibrates are contraindicated in patients with renal failure because of a high risk of rhabdomyolysis. These issues are discussed in the current review article. Based on published work, lipid lowering would not increase the death rate if carried out without worsening malnutrition. The National Kidney Foundation K/DOQI Clinical Practice Guidelines recommend a reduction in fasting LDL-C below 100 mg/dL for the prevention of CVD in dialysis patients. Practically, however, the use of non-HDL-C measured by casual blood samples might be sufficient for the risk assessment in many hemodialysis patients. Statins are a good choice for lipid-lowering in dialysis patients. Furthermore, lipoprotein profile might be improved by an inventive use of dialyzer membranes, dialysate solutions, and other dialysis-related medications. For severe hypercholesterolemia, LDL-apheresis is another choice for consideration. Further studies are needed to clearly prove the benefit of lipid reduction in hemodialysis patients and those with CKD at earlier stages.

Body fat mass and lean mass as predictors of survival in hemodialysis patients

A higher body mass index (BMI) is a predictor of better survival in hemodialysis patients, although the relative importance of body fat and lean mass has not been examined in the dialysis population. We performed an observational cohort study in 808 patients with end-stage renal disease on maintenance hemodialysis. At baseline, fat mass was measured by dual-energy X-ray absorptiometry and expressed as fat mass index (FMI; kg/m2). Lean mass index (LMI) was defined as BMI minus FMI. During the mean follow-up period of 53 months, 147 deaths, including 62 cardiovascular (CV) and 85 non-CV fatal events, were recorded. In univariate analysis, LMI was not significantly associated with CV or non-CV death, whereas a higher FMI was predictive of lower risk for non-CV death. Analyses with multivariate Cox models, which took other confounding variables as covariates, indicated the independent associations between a higher LMI and a lower risk of CV death, as well as between a higher FMI and a lower risk of non-CV death. These results indicate that increased fat mass and lean mass were both conditions associated with better outcomes in the dialysis population.

Effect of soya protein on serum lipid profile and lipoprotein concentrations in patients undergoing hypercholesterolaemic haemodialysis

Clinical trials have shown that soya protein reduces the concentrations of some atherogenic lipids in subjects with normal renal function. The present study examined the effects of soya protein on serum lipid concentrations and lipoprotein metabolism in patients on hypercholesterolaemic haemodialysis. Twenty-six hypercholesterolaemic (total cholesterol > or =6.21 mmol/l) patients on haemodialysis were studied in a randomized, double-blind, placebo-controlled clinical trial. After a 4-week run-in phase, the subjects were randomly assigned to two groups. Isolated soya protein or milk protein 30 g was consumed daily as a beverage at breakfast or post-dialysis for 12 weeks. Soya protein substitution resulted in significant reductions in total cholesterol (17.2 (sd 8.9 )%), LDL-cholesterol (15.3 (sd 12.5 )%), apo B (14.6 (sd 12.1 )%) and insulin (23.8 (sd 18.7) %) concentrations. There were no significant changes in HDL-cholesterol or apo A-I. These results indicate that replacing part of the daily protein intake with soya protein has a beneficial effect on atherogenic lipids and favourably affects lipoprotein metabolism in hypercholesterolaemic patients undergoing haemodialysis.

Variable effects of soy protein on plasma lipids in hyperlipidemic and normolipidemic hemodialysis patients

BACKGROUND

Hyperlipidemic factors contribute to the high cardiovascular risk in hemodialysis patients. Soy protein has decreased some atherogenic lipid concentrations in subjects with normal renal function. This study evaluates the effect of soy protein on serum lipid profiles in hyperlipidemic and normolipidemic hemodialysis patients.

METHODS

Nineteen hyperlipidemic and 18 normolipidemic hemodialysis patients were enrolled in a randomized, double-blind, placebo-controlled, clinical trial. After a 4-week run-in phase, subjects in each category were randomly assigned to 2 groups. Thirty grams of isolated soy protein or milk protein was consumed daily as a beverage at breakfast or postdialysis for 12 weeks.

RESULTS

In hyperlipidemic subjects, soy protein intake significantly decreased total cholesterol levels by 18.6% (95% confidence interval [CI], -11.4 to -25.8; P = 0.04), triglyceride levels by 43.1% (95% CI, -34.0 to -52.2; P = 0.02), non-high-density lipoprotein cholesterol levels by 23.6% (95% CI, -14.7 to -32.5; P < 0.01), apolipoprotein B levels by 15.4% (95% CI, -5.4 to -25.4; P = 0.01), and insulin levels by 49.8% (95% CI, -23.3 to -66.1; P < 0.01). Low-density lipoprotein cholesterol concentration was decreased significantly (-25.8%; 95% CI, -8.3 to -42.7; P = 0.01), and high-density lipoprotein cholesterol level was increased significantly (17%; 95% CI, 2 to 32.0; P = 0.03), but there was no significant difference compared with the milk protein group (-5.5% +/- 16.9% and 7.0% +/- 11.8%, respectively). There were no significant changes in serum lipid and lipoprotein concentrations in normolipidemic subjects.

CONCLUSION

These results indicate soy protein substitution has lipid-lowering effects in hyperlipidemic hemodialysis patients. However, soy protein intake had little effect on plasma lipid levels in normolipidemic hemodialysis patients.

Endocrinology and Dialysis Jean L. HolleySeries Editor: Lipid Abnormalities Associated with End-Stage Renal Disease

Patients undergoing chronic renal replacement therapy have a high incidence of dyslipidemia. In general, there are increased concentrations of triglyceride-rich apolipoprotein B-containing particles. These elevations lead to increased levels of non-high-density lipoprotein (HDL) levels. This pattern is further modified by the method of dialysis (peritoneal versus hemodialysis) and comorbidities such as diabetes. End-stage renal disease patients also demonstrate increased levels of lipoprotein(a) (Lp(a)) and oxidized low-density lipoprotein (LDL)both of which are highly atherogenic. This review focuses on the pathogenesis of these lipid abnormalities and their role in the atherosclerotic process.

Non-high-density lipoprotein cholesterol versus low-density lipoprotein cholesterol as a risk factor for a first nonfatal myocardial infarction

Low-density lipoprotein (LDL) cholesterol is the primary lipid parameter targeted to prevent myocardial infarction. Alternatively, non-high-density lipoprotein (HDL) cholesterol includes LDL cholesterol and other atherogenic particles but does not require a fasting sample. Non-HDL cholesterol and LDL cholesterol as predictors of first nonfatal myocardial infarction were compared in 303 patients and 297 controls matched for age, gender, and community within the Boston Area Health Study. Patients were white men or women aged <76 years living in the Boston area, without a history of myocardial infarction or angina pectoris, in whom symptoms of confirmed myocardial infarction began during the 24 hours before admission. After multivariate adjustment for coronary risk factors in unmatched analyses, the corresponding odds ratios (ORs) of a first nonfatal myocardial infarction for non-HDL cholesterol in the second, third, and fourth quartiles were 1.83 (95% confidence interval [CI] 1.07 to 3.14), 2.07 (95% CI 1.23 to 3.49), and 2.33 (95% CI 1.39 to 3.90) (p trend <0.01). For LDL cholesterol, the ORs were 1.10 (95% CI 0.67 to 1.81), 0.87 (95% CI 0.52 to 1.46), and 1.45 (95% CI 0.90 to 2.35) (p trend = 0.16). Including HDL cholesterol in the model increased the ORs and strengthened the test for a trend for LDL cholesterol, whereas the ORs were decreased and the test for a trend was weakened for non-HDL cholesterol. In conclusion, given that non-HDL cholesterol accounts for LDL cholesterol plus other atherogenic particles but does not require a fasting sample, this study suggests that non-HDL cholesterol may be at least as useful as LDL cholesterol to initially screen patients for risk of a first nonfatal myocardial infarction.

Introduction to Sevelamer Hydrochloride and its Clinical Effects

Sevelamer hydrochloride (SH) is widely used for the treatment of hyperphosphatemia in patients with renal failure who are on maintenance hemodialysis. In this study, we investigated the clinical effects of SH, administered as either monotherapy or combined with a calcium carbonate formulation, on the metabolism of calcium (Ca) and phosphorus (P) in patients who had been taking a Ca-based binder. Patients were divided into three groups (i): switched completely from a Ca-based binder to SH (complete switch); (ii) dosage of the Ca-based binder was reduced, and SH introduced (partial switch); and (iii) dosage of the Ca-based binder was not reduced and SH introduced (combination therapy). We also examined the effects of the introduction of SH on the lipid profile and parathyroid hormone (PTH) concentration. Comparison between groups of the numbers of successfully treated cases (reaching target concentrations of serum P=5.5 mg/dL and Ca x P product=55 mg2/dL2 within 6 months of treatment) showed that the likelihood of reaching target levels was higher if Ca-based binder was maintained as much as possible (combination therapy>partial changeover>complete changeover). Furthermore, treatment with SH decreased total cholesterol and non-HDL cholesterol concentrations significantly, and also increased HDL cholesterol and PTH concentrations compared to pre-treatment. These results suggest that when a calcium carbonate formulation is already in use, as far as compliance allows, the dosage should not be reduced when SH is added. Despite its beneficial effects on the lipid and PTH concentrations, preventing an excessive increase in the PTH concentration is essential when using SH.

Nonfasting Non-High-Density Lipoprotein Cholesterol Is Adequate for Lipid Management in Hemodialysis Patients

BACKGROUND

Guidelines for the management of dyslipidemia in patients with chronic kidney disease are based on results from the fasting lipid profile, which can be difficult to obtain from patients on an afternoon or night dialysis schedule. The present study tests the hypothesis that nonfasting non-high-density lipoprotein (HDL) cholesterol (total cholesterol-HDL cholesterol) results are similar to fasting non-HDL results as a basis for the management of dyslipidemia in hemodialysis patients.

METHODS

Forty-eight long-term hemodialysis patients with a mean age of 63.6 years (42% with diabetes, 54% administered statins) participated in this study. For the lipid profile, blood samples were drawn after a 12-hour overnight fast (fasting) and again in a nonfasting state before the subsequent hemodialysis session. Data were analyzed by using paired t-test and regression analysis.

RESULTS

Non-HDL cholesterol values were nearly identical regardless of whether the patient was fasting (r2 = 0.995). Only 2 patients (4%) had a nonfasting triglyceride (TG) level greater than 500 mg/dL (> 5.6 mmol/L), which would have required confirmation after an overnight fast. Non-HDL values had the greatest level of correlation (absolute relative difference, 5.7%). When comparing the subgroup of patients with a TG level less than 200 mg/dL (< 2.3 mmol/L), nonfasting non-HDL cholesterol values identified 3 additional patients compared with fasting calculated low-density lipoprotein cholesterol for whom lipid-lowering therapy would have been introduced according to current guidelines.

CONCLUSION

In our study, non-HDL cholesterol levels were equivalent whether evaluated in the fasting or nonfasting state. We recommend that nonfasting non-HDL cholesterol level be used for the management of dyslipidemia in hemodialysis patients without imposing a 12-hour fast period.