Dietary fish oil lowers lipoprotein(a) in primary hypertriglyceridemia

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.

The present study was conducted using a double-blind, permuted-randomized, controlled experimental protocol.

This study took place at the Central Texas Nephrology Associates Dialysis Clinic (Waco, TX).

Patients with ESRD and associated with the Central Texas Nephrology Associates who were undergoing chronic hemodialysis participated in this study.

Patients with ESRD were followed prospectively while receiving supplements of fish oil (treatment, eicosapentaenoic acid, 0.96 g/day, and docosahexaenoic acid, 0.6 g/day) or corn oil (control subjects) for 6 months. After a 12-hour fast, participants donated 12 mL of blood for analysis of Lp(a) at baseline and at 6 months.

The comparison of Lp(a) concentration by group at 6 months was the primary outcome measure of the study.

Our study suggests that fish-oil supplementation did not decrease levels of Lp(a) (P = .66), compared with control subjects.

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.

Fish oils have been widely reported as a useful supplement to reduce fasting blood triglyceride levels in individuals with hyperlipidemia. We performed an updated meta-analysis to quantitatively evaluate all the randomized trials of fish oils in hyperlipidemic subjects.

We conducted a systematic literature search using several electronic databases supplemented by manual searches of published reference lists, review articles and conference abstracts. We included all placebo-controlled randomized trials of parallel design that evaluated any of the main blood lipid outcomes: total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol or triglycerides (TG). Data were pooled using DerSimonian–Laird's random effects model.

The final analysis comprised of 47 studies in otherwise untreated subjects showed that taking fish oils (weighted average daily intake of 3.25 g of EPA and/or DHA) produced a clinically significant reduction of TG (− 0.34 mmol/L, 95% CI: − 0.41 to − 0.27), no change in total cholesterol (− 0.01 mmol/L, 95% CI: − 0.03 to 0.01) and very slight increases in HDL (0.01 mmol/L, 95% CI: 0.00 to 0.02) and LDL cholesterol (0.06 mmol/L, 95% CI: 0.03 to 0.09). The reduction of TG correlated with both EPA + DHA intake and initial TG level.

Fish oil supplementation produces a clinically significant dose-dependent reduction of fasting blood TG but not total, HDL or LDL cholesterol in hyperlipidemic subjects.

Dietary therapy using phytosterols can reinforce statin treatment; however the value of a low-dose combination of those agents remains to be investigated. Plant sterols (PS), dissolved in diacylglycerol (DAG) oil, (PS/DAG) can be effective at a relatively low dose. The objective of the present study was to examine the effect of PS/DAG oil on blood cholesterol concentrations in hypercholesterolemic outpatients on low-dose pravastatin (10 mg/day).

The patients (n = 61) were randomly assigned to one of three groups, who consumed TAG (control), DAG or PS/DAG oil. The average intake of PS from the PS/DAG oil during the test period was significantly higher than that for TAG and DAG oils (502 vs. 49 and 38 mg/day, P < 0.05). Significant cholesterol-lowering effects from the baseline were observed in the case of the PS/DAG oil treatment alone. Changes in low-density lipoprotein (LDL) cholesterol were inversely correlated with baseline serum campesterol concentrations (r = −0.560, P < 0.05), but not baseline LDL cholesterol concentrations. In addition, serum apolipoprotein B concentrations were reduced to a greater extent in subjects with high versus low levels of baseline campesterol (−13.2 mg/dL vs. −3.1 mg/dL, P < 0.05). Furthermore, there was a mild, but significant reduction in serum lipoprotein (a) concentration from the baseline (−5.9 mg/dL), which was correlated with the reduction in serum apolipoprotein B concentration (r = 0.596, P < 0.05).

A low-dose combination of PS/DAG oil and pravastatin may be a useful strategy for further ameliorating blood cholesterol and lipoprotein (a) concentrations for hypercholesterolemic patients with a low response to pravastatin.

High plasma lipoprotein (a) [Lp(a)] concentrations are an independent risk factor for atherosclerotic diseases. To date, no effective intervention strategies on reducing Lp(a) concentrations have been reported. The aim of the study was to evaluate the possible modulation of two polymorphisms of LPA gene (LPA 93C>T and LPA 121G>A) and nutritional habits on Lp(a) concentrations. We studied 647 healthy Italian subjects (260 M; 387 F) with a median age of 48 years (range: 19–78) enrolled in an epidemiological study conducted in Florence, Italy. A linear regression analysis showed a significant negative influence of fish intake (β = −0.174 ± 0.084; p = 0.04) on Lp(a) concentrations, after adjustment for smoking habit, C-reactive protein serum concentrations, dietary habits and LDL-cholesterol concentrations. With regard to LPA polymorphisms, LPA 93C>T polymorphism resulted to significantly affect Lp(a) circulating concentrations in a dose-dependent manner, with lower concentrations shown by subjects carrying the T rare allele, whereas no significant influence of LPA 121G>A polymorphism on Lp(a) concentrations was observed. Moreover, by analyzing the possible interplay between LPA 93C>T and dietary fish intake, a significant interaction between these two determinants in lowering Lp(a) concentrations was reported. In addition, lower Lp(a) concentrations were observed in subjects carrying the T allele of the LPA 93C>T polymorphism and consuming a high intake of fish with respect to those being in the highest tertile of fish consumption but homozygotes for the common allele of the polymorphism. In conclusion, this study reported a significant interaction of daily fish intake and LPA 93C>T polymorphism in decreasing Lp(a) concentrations.

Atherogenic blood lipoprotein levels are dramatically increased during menopause. The solubilization of plant sterols (PS) in a diacylglycerol (DAG)-rich oil has recently been proposed as a more effective method of incorporating PS into food products; however, the effect of PS solubilized in DAG oil on serum lipid abnormalities in women after menopause is unknown. The effect of the daily consumption of DAG oil containing PS (4 wt%, PS/DAG) oil on serum lipid parameters was examined in postmenopausal women.

Fourteen postmenopausal women with mild to moderate hypercholesterolemia were randomly assigned to treatment with either PS/DAG or DAG (control) oil, and were instructed to replace the ordinary cooking oils used at home for 4 weeks in a crossover manner.

The average intake of PS from the PS/DAG and control oils were 563 and 50 mg/day, respectively (P=0.001). During control period, no effect on serum triacylglycerol and cholesterol concentrations was observed. Serum total cholesterol, low-density lipoprotein cholesterol and apolipoprotein B concentrations reduced by 10.2% (P=0.004), 12.1% (P=0.003) and 9.7% (P=0.001) during the PS/DAG oil period compared to the control period, respectively. In addition, a slight but significant (P=0.023) reduction in serum lipoprotein(a) concentration was observed, especially, in subjects with higher levels of baseline values (>20 mg/dL).

Dietary PS/DAG oil may be a useful adjunct for the management not only of blood cholesterols, but also of lipoprotein (a) in postmenopausal women.

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease of unknown cause that can affect any organ, and is characterized by a wide range of autoantibodies. Several studies of large cohorts of SLE patients have reported an increased prevalence of symptomatic subclinical cardiovascular disease (CVD). It is currently believed that accelerated atherosclerosis in SLE results from a combination of numerous risk factors. In addition to a high prevalence of traditional risk factors, inflammatory processes in SLE are considered to be important in atherogenesis. Chronic activation or damage to the endothelium in SLE may trigger the inflammatory cascade and thereby promote atherogenesis. Several forms of endothelial insult are being recognized in SLE, including hypercholesterolemia, hyperhomocysteinemia, mechanical stress from hypertension, increased oxidative stress and immunologic injury as a result of immune complex deposition. This review updates the modifiable risk factors in SLE. The main focus is on the potential utility of these risk factors. The putative mechanisms of accentuated risk as a result of underlying inflammation, and evidence for association with premature atherosclerosis are discussed. Strategies that may be useful in preventing the progression of atheroma in this population include close monitoring and aggressive treatment of the traditional risk factors as in patients with high risk of CVD. The role of antioxidants and immunomodulators are also explored.