Effect of over-the-counter fish-oil administration on plasma Lp(a) levels in an end-stage renal disease population.

OBJECTIVE: This study sought to examine the effect of n-3 supplementation on lipoprotein(a) (Lp(a)) levels in end-stage renal disease (ESRD) patients undergoing chronic hemodialysis. DESIGN: The present study was conducted using a double-blind, permuted-randomized, controlled experimental protocol. SETTING: This study took place at the Central Texas Nephrology Associates Dialysis Clinic (Waco, TX). PATIENTS: Patients with ESRD and associated with the Central Texas Nephrology Associates who were undergoing chronic hemodialysis participated in this study. INTERVENTION: Patients with ESRD were followed prospectively while receiving supplements of fish oil (treatment, eicosapentaenoic acid, 0.96g/day, and docosahexaenoic acid, 0.6g/day) or corn oil (control subjects) for 6 months. After a 12-hour fast, participants donated 12mL of blood for analysis of Lp(a) at baseline and at 6 months. MAIN OUTCOME MEASURE: The comparison of Lp(a) concentration by group at 6 months was the primary outcome measure of the study. RESULTS: Our study suggests that fish-oil supplementation did not decrease levels of Lp(a) (P=.66), compared with control subjects. CONCLUSION: We failed to show a significant effect of 6 months of over-the-counter fish-oil supplementation on Lp(a) status in an ESRD population, although results from this study support findings from other studies suggesting that African Americans have higher Lp(a) concentrations than persons of Caucasian decent.

Effects of omega-3 fatty acid supplementation on lipid levels in endstage renal disease patients.

OBJECTIVE: Our purpose was to determine if over-the-counter fish oil improves the cardiovascular-disease risk profile of endstage renal disease patients. DESIGN: This study used a double-blind, permuted-block, randomized, placebo-controlled design. The experimental intervention consisted of fish-oil concentrate supplementation, whereas corn-oil capsules were used as a control. Compliance follow-ups were performed 3 times per week. SETTING: Patients of Central Texas Nephrology Associates clinics were eligible for this study. PATIENTS: Exclusion criteria comprised a life-expectancy of less than 6 months, pregnancy, a history of hemodialysis or medication noncompliance, or age below 18 years. The final sample size was 87 patients. The attrition rate was 9%. INTERVENTION: Participants in the experimental group consumed six 1-g soft-gel capsules of fish-oil concentrate each day for 6 months. The control group consumed corn-oil capsules, following the same protocol. Venous blood samples were acquired before and after the intervention. MAIN OUTCOME MEASURE: We assessed a number of serum lipid indicators. RESULTS: There were significant supplement/time interactions in low-density lipoprotein cholesterol (LDL) levels (P = .0001) and LDL particle number (P = .0001). Repeated-measures analysis of variance revealed significant time trends in high-density lipoprotein cholesterol (P = .012) and LDL (P = .001). High-density lipoprotein cholesterol levels significantly decreased in the control group, and increased in the fish-oil group, at 6 months, and LDL levels increased significantly in both groups. CONCLUSIONS: The analysis indicates mixed results with respect to cardiovascular disease risk. Further research is needed to assess the benefits of an over-the-counter fish-oil supplement in the renal population.

Fish oil supplementation lowers C-reactive protein levels independent of triglyceride reduction in patients with end-stage renal disease.

BACKGROUND: Inflammation has been identified as a marker for cardiovascular disease. The purpose of this study is to examine the effects of fish oil fatty acid supplementation on C-reactive protein (CRP) levels. METHODS: The study uses a double-blind, permuted-randomized, and placebo-controlled experimental protocol. Patients are randomly placed into a fish oil group or a control group. Thirty-three patients in the experimental and control groups ingest 2 soft-gel pills (1 g each) of fish oil supplements containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) or placebo at each meal. Patients follow the supplementation protocol for 6 months. Analysis of variance (ANOVA) is used to measure pretest and posttest differences in the variable of interest. A Kolmogorov-Smirnov test for normality is used to test whether CRP levels are normally distributed. RESULTS: The Kolmogorov-Smirnov test for CRP finds a P value of .273 (KS = .997), revealing that the distribution is normal. ANOVA reveals no statistically significant difference between groups at baseline for CRP (F = 4.118, P = .053). ANOVA reveals a significant main effect (F = 4.29, P = .048) for CRP, with the EPA/DHA group having a significant change in values from pretest (16 mg/dL, standard deviation [SD] = 13.80) to posttest (10.22 mg/dL, SD = 7.87). The placebo group's CRP levels do not change significantly from pretest (13.37, standard deviation [SD] = 7.94) to posttest (13.67, SD = 7.07). An observed power calculation using Cohen's D with a computed alpha of .05 is .588. CONCLUSIONS: The study demonstrates that consuming 960 mg/d of EPA and 600 mg/d of DHA can lower CRP.

Omega-3 fatty acid supplementation and total homocysteine levels in end-stage renal disease patients.

AIM: Elevated total homocysteine (tHcy) levels are commonplace among end-stage renal disease (ESRD) patients increasing risk for poor cardiovascular outcomes. Specifically, when plasma levels become significantly elevated, tHcy levels appear to contribute to vascular damage and premature atherosclerosis. The purpose of this study was to examine the effect of an over-the-counter omega-3 (n-3) fatty acid supplementation on tHcy levels in ESRD patients undergoing chronic haemodialysis. METHODS: The present study was conducted using a double-blind, permuted-randomized and placebo-controlled experimental protocol. ESRD patients were followed prospectively while supplementing n-3 or corn oil (n-6) prospectively for 6 months. PATIENTS: Sixty-nine patients were recruited that had previously demonstrated compliance with dialysis and medication. Following a 12 h fast, participants donated 12 mL of blood for analysis of tHcy at baseline and at 6 months. RESULTS: The results of this study using regression models revealed no differences in age and gender regarding homocysteine levels at the post-test with P-values of 0.6818, 0.6709 and 0.3331 for each regression model. The study findings also revealed that daily administration of 6 g of n-3 fatty acids containing 160 mg of eicosapentaenic acid (0.96 g/day) and 100 mg of docosahexaenoic acid (0.6 g/day) had no effect on tHcy levels when compared with control. CONCLUSION: Potential reasons for this non-significant result may be found in a dose-response relationship, advancement of disease progression in our sample population, or potentially the lack of a significant relationship between fish oil and tHcy. Future studies should address whether a dose-response relationship between n-3 fatty acid supplementation and tHcy levels exists, and how stage of disease progression affects intervention success or failure.

Comparison of lipid measures and risk stratification among end-stage renal disease patients.

BACKGROUND: Abnormal lipid profiles are associated with end-stage renal disease (ESRD) which significantly contributes to an accelerated progression of coronary artery disease. The purpose of this study was to examine the relationships between cholesterol measures and differences in risk stratification when using National Cholesterol Education Program, Adult Treatment Panel, Third Report (ATP-III) guidelines, compared with cholesterol particle number and size in ESRD patients. METHODS: Lipid profiles were conducted on 541 ESRD patients who were chronic hemodialysis patients. Lipid profiles were measured using gel electrophoresis and their particle size and concentration measured using nuclear magnetic resonance (NMR) spectroscopy. Correlations and risk stratification were compared between each lipid measure. RESULTS: The findings suggest that low-density lipoprotein (LDL) size does not correlate well with LDL cholesterol and LDL particle number. The findings also suggest a "disconnect" between traditional lipid measures and cholesterol concentration and size when using ATP-III guidelines for risk stratification. CONCLUSIONS: The cholesterol risk designation variances between risk stratification guidelines and the relationships established through Pearson correlations, as illustrated within this patient pool, reveal the complex differences between measures of coronary artery disease risk. These additional patients considered at-risk using NMR technology may help to identify more patients at need for intervention and treatment.

Effects of omega-3 fatty acid supplementation on vascular access thrombosis in polytetrafluorethylene grafts.

OBJECTIVE: The purpose of this study was to investigate the effects of orally administered over-the-counter omega-3 (n-3) fatty acid supplements on primary patency of polytetrafluoroethylene (PTFE) grafts. DESIGN: This study was conducted with a triple-blind, permuted-block, randomized, placebo-controlled experimental design. SETTING: Dialysis clinics with patients who, in accordance with physician diagnosis, needed a new PTFE graft. PATIENTS AND OTHER PARTICIPANTS: Patients on long-term hemodialysis with newly placed PTFE grafts who were unable to receive a native arteriovenous fistula. INTERVENTION: Patients were followed prospectively for 8 months after they had been placed into an n-3 fatty acid or control group and were monitored for primary patency. MAIN OUTCOME VARIABLE: Primary patency of the PTFE graft. RESULTS: The n-3 fatty acid group had a mean PTFE graft primary patency rate of 254.2 days (SEM = 51.8), and the control group had a mean PTFE graft primary patency rate of 254.1 days (SEM = 34.6), revealing no significant difference in survival time between groups. CONCLUSIONS: No significant differences in primary patency rates were noted in the experimental and control groups.

Homocysteine and vascular access thrombosis in a cohort of end-stage renal disease patients.

BACKGROUND: Maintaining successful hemodialysis services is dependent upon an access to circulation that is reliable and stable. Complications of vascular access such as dysfunction, thrombosis, or infection are major causes of hospitalization with thrombosis being the most common reoccurring problem. Initial prospective evidence supports an independent association between total homocysteine (tHcy) levels and access thrombosis. The purpose of this study was to determine if significant associations exist between tHcy, age, gender, and vascular access thrombosis in patients with end-stage renal disease (ESRD). SUBJECTS AND METHODS: One hundred eighty-five (N=185) patients undergoing dialysis were selected as subjects. The retrospective sample was divided into a one or less vascular access thrombosis (VAT) (VAT) group (n= 133) and more than one (VAT II) VAT group (n= 52). The data was collected during a 16-month period (January 2000 to April 2002). Additional subgroup analyses included gender and age. RESULTS: The Mann-Whitney U nonparametric t-Test for variance between groups revealed no significant difference in tHcy values between VAT groups (U=1841.50, p=0.284). A two-sample t-Test for variance between tHcy and age revealed no significant differences (F-ratio = 0.832, p = 0.32). A chi-square analysis revealed no significant differences in gender and VAT groups (chi2=0.246, p=0.62). A Kolmogorov-Smirnov test for normality was calculated for tHcy with a p-value of 0.859 revealing insufficient evidence that the distribution is not normal. Spearman Rank Correlations were calculated, revealing low to moderate associations among variables. CONCLUSIONS: While some studies have demonstrated a relationship between tHcy and VAT, this study found that chronically high homocysteine levels in patients with ESRD were not associated with incidence of VAT. There were no significant differences in the number of VATs across additional variables of age and gender.