Effect of Omega-3 fatty acids on blood pressure and serum lipids in continuous ambulatory peritoneal dialysis patients

Chemical Analysis of Various Tea Samples Concerning Volatile Compounds, Fatty Acids, Minerals and Assessment of Their Thermal Behavior

Tea is the most consumed drink worldwide due to its pleasant taste and various beneficial effects on human health. This paper assesses the physicochemical analysis of different varieties of tea (leaves, flowers, and instant) after prior drying and fine grinding. The thermal decomposition behavior of the tea components shows that the tea has three stages of decomposition, depending on temperature. The first stage was attributed to the volatilization of water, while the second stage involved the degradation of volatiles, polyphenols, and fatty acids. The degradation of cellulose, hemicellulose, and lignin content occurs at the highest temperature of 400 °C in the third stage. A total of 66 volatile compounds, divided into eight classes, were identified in the tea samples. The volatile compounds were classified into nine odor classes: floral, fruity, green, sweet, chemical, woody, citrus, roasted, and alcohol. In all flower and leaf tea samples, monounsaturated (MUFAs), polyunsaturated (PUFAs), and saturated fatty acids (SFAs) were identified. A high content of omega-6 was quantified in acacia, Saint John's Wort, rose, and yarrow, while omega-3 was found in mint, Saint John's Wort, green, blueberry, and lavender samples. The flower and leaf tea samples studied could be a good dietary source of polyphenolic compounds, essential elements. In instant tea samples, a low quantity of polyphenols and major elements were identified. The physicochemical analysis demonstrated that both flower and leaf teas have high-quality properties when compared to instant tea.

The association of lipid-lowering therapy and blood pressure control among outpatients with hypertension at the Felege Hiwot Comprehensive Specialized Hospital, Northwest Ethiopia

Background

The lipid-lowering medications known as statins have been shown in controlled clinical trials to have pleiotropic properties, such as lowering blood pressure, in addition to lowering cholesterol levels. The purpose of this study was to see if there was a possible link between blood pressure control and statin therapy in outpatients with hypertension in a real clinical setting.

Patients and methods

A retrospective comparative cohort study of 404 patients with hypertension was carried out. A systematic random sampling technique was used. For data entry, Epi-Data version 4.6 was used, and SPSS version 25 was used for further analysis. For group comparisons, chi-square and independent t-tests were computed. To determine the relationship between statin use and blood pressure control, a binary logistic regression model was employed. To declare statistical significance, a 95% confidence interval and a P-value of <0.05 were used.

Results

Half of the study participants who were using a prescribed statin were assigned to the statin group, whereas the remaining participants who do not take statins were assigned to the control group. After 3 months of statin treatment, BP control to <130/80 mmHg was significantly greater (P = 0.022) in the statin group (52.5%) than in the control group (41.0%). The use of statins raises the likelihood of having blood pressure under control by 1.58 times when compared to statin non-users. After controlling for possible confounders, statin therapy still increased the odds of having controlled BP by a factor of 5.98 [OR = 5.98; 95% CI: 2.77-12.92].

Conclusion

This study revealed that blood pressure control was higher among statin user hypertensive patients. Favorable effects of statin use were independently observed, even after correction for age, presence of dyslipidemia, and duration of antihypertensive therapy. Therefore, the importance of concomitantly added lipid-lowering drugs such as statins and their role in managing poor blood pressure control should be given due emphasis.

Associations of genetically predicted fatty acid levels across the phenome: A mendelian randomisation study

BACKGROUND

Fatty acids are important dietary factors that have been extensively studied for their implication in health and disease. Evidence from epidemiological studies and randomised controlled trials on their role in cardiovascular, inflammatory, and other diseases remains inconsistent. The objective of this study was to assess whether genetically predicted fatty acid concentrations affect the risk of disease across a wide variety of clinical health outcomes.

METHODS AND FINDINGS

The UK Biobank (UKB) is a large study involving over 500,000 participants aged 40 to 69 years at recruitment from 2006 to 2010. We used summary-level data for 117,143 UKB samples (base dataset), to extract genetic associations of fatty acids, and individual-level data for 322,232 UKB participants (target dataset) to conduct our discovery analysis. We studied potentially causal relationships of circulating fatty acids with 845 clinical diagnoses, using mendelian randomisation (MR) approach, within a phenome-wide association study (PheWAS) framework. Regression models in PheWAS were adjusted for sex, age, and the first 10 genetic principal components. External summary statistics were used for replication. When several fatty acids were associated with a health outcome, multivariable MR and MR-Bayesian method averaging (MR-BMA) was applied to disentangle their causal role. Genetic predisposition to higher docosahexaenoic acid (DHA) was associated with cholelithiasis and cholecystitis (odds ratio per mmol/L: 0.76, 95% confidence interval: 0.66 to 0.87). This was supported in replication analysis (FinnGen study) and by the genetically predicted omega-3 fatty acids analyses. Genetically predicted linoleic acid (LA), omega-6, polyunsaturated fatty acids (PUFAs), and total fatty acids (total FAs) showed positive associations with cardiovascular outcomes with support from replication analysis. Finally, higher genetically predicted levels of DHA (0.83, 0.73 to 0.95) and omega-3 (0.83, 0.75 to 0.92) were found to have a protective effect on obesity, which was supported using body mass index (BMI) in the GIANT consortium as replication analysis. Multivariable MR analysis suggested a direct detrimental effect of LA (1.64, 1.07 to 2.50) and omega-6 fatty acids (1.81, 1.06 to 3.09) on coronary heart disease (CHD). MR-BMA prioritised LA and omega-6 fatty acids as the top risk factors for CHD. Although we present a range of sensitivity analyses to the address MR assumptions, horizontal pleiotropy may still bias the reported associations and further evaluation in clinical trials is needed.

CONCLUSIONS

Our study suggests potentially protective effects of circulating DHA and omega-3 concentrations on cholelithiasis and cholecystitis and on obesity, highlighting the need to further assess them as prevention treatments in clinical trials. Moreover, our findings do not support the supplementation of unsaturated fatty acids for cardiovascular disease prevention.

A Consistency Model for Identifying the Effects of n-3 and n-6 Fatty Acids on Lipoproteins in Dialysis Patients

Numerous randomized controlled trials (RCTs) and meta-analyses have assessed the effects of supplemental dietary polyunsaturated fatty acids (PUFAs) on levels of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) and the LDL/HDL ratio in patients receiving renal replacement therapy (RRT). However, results are ambiguous due to mixed reports of various nutrients used in the intervention group. We performed a network meta-analysis of RCTs to assess the effects of PUFAs on lipid profiles in patients undergoing RRT. RCTs performed before November 2021 were gathered from three databases. The means, standard deviations and the number of cases for each arm were independently extracted by two authors to form a network meta-analysis of LDL and HDL levels and the LDL/HDL ratio in a random effects model. Twenty-eight RCTs (n = 2017 subjects) were included in this study. The pooled results revealed that the combination of omega-3 fatty acids (n-3) and omega-6 fatty acids (n-6) produced significantly lower LDL (standardized mean difference (SMD) = −1.43, 95% confidence interval: −2.28 to −0.57) than the placebo. Both n-3 fatty acids (SMD = 0.78) and the combination of n-3 + n-6 (SMD = 1.09) benefited HDL significantly compared with placebo. Moreover, n-3 alone also exhibited a significantly lower LDL/HDL ratio than placebo. Collectively, PUFAs seem to be adequate nutrients for controlling lipoproteins in patients undergoing RRT. Specifically, n-3 + n-6 supplementation improved LDL levels, while n-3 improved HDL levels and the LDL/HDL ratio. However, our data provide limited information on specific dosages of PUFAs to form a concrete recommendation.

Effects of Omega-3 Fatty Acid Intake in Patients Undergoing Dialysis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective: Fish oil supplementation has been shown to be beneficial for hemodialysis (HD) patients. The aim of this study was to evaluate the efficacy and safety of omega-3 fatty acid supplementation or dietary adjustment in dialysis patients.Methods: A systematic literature search was performed to identify relevant randomized controlled trials (RCTs) to study the effects of omega-3 supplementation on dialysis patients. The variables of interest included the levels of blood lipids, inflammatory indicators, proteins, parathyroid hormone (PTH), gastrointestinal adverse reactions, and all-cause mortality. The mean differences (MDs) and 95% confidence intervals (CIs) were calculated, and heterogeneity was assessed with the I² test. Subgroup and sensitivity analyses were performed to identify potential sources.Results: The systematic review included 49 RCTs and evaluated the efficacy and safety of omega-3 fatty acid supplementation in dialysis patients. Data synthesis showed that compared with the control group, the group receivingomega-3 supplementation exhibited significantly decreased serum triglyceride (TG) levels, decreased C-reactive protein (CRP) and TNF-alpha levels, increased hemoglobin levels, reduced serum phosphorus levels, increased PTH levels, and increased gastrointestinal adverse reactions to a certain extent. Furthermore, there was no effect on the blood total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), albumin or calcium levels and all-cause mortality.Conclusion: Omega-3 fatty acid supplementation is related to a reduction in serum TG, LDL and inflammation index levels and has few adverse reactions. Therefore, omega-3 fatty acid supplementation may be a useful nutrition therapy for dialysis patients.

Association of polyunsaturated fatty acids with improved heart rate variability and cardiovascular events in patients with end-stage renal disease receiving maintenance dialysis: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Apart from dietary restriction and medical therapy, the benefits of cardiovascular protection offered by polyunsaturated fatty acid (PUFA) supplements in patients with ESRD receiving maintenance dialysis remain unclear. This systematic review and meta-analysis examined the effects of PUFAs on blood pressure, heart rate (HR), HR variability (HRV), and cardiovascular disease (CVD) prognosis.

METHODS

We identified randomized controlled trials (RCTs) from Embase, PubMed (including MEDLINE), and Web of Science. We included seven RCTs that involved 724 patients with ESRD receiving dialysis and PUFA supplements.

RESULTS

The data indicated that compared with the control group, the PUFA group demonstrated decreased cardiovascular events (Peto odds ratio = 0.52, 95% confidence interval [CI] = 0.32 to 0.85, P = 0.009) and HRV (changes in the mean HR [mean difference = -2.59, 95% CI = -4.91 to -0.26, P = 0.03, I² = 0%]; mean RR interval [MD = 29.03, 95% CI = 5.43 to 52.63, P = 0.02, I² = 0%]; mean of the standard deviation of all normal RR intervals for all 5 min segments [MD = 2.73, 95% CI = 0.48 to 4.99, P = 0.02, I² = 0%], and square root of the mean of the sum of the squares of differences between adjacent intervals [MD = 2.03, 95% CI = 0.04 to 4.03, P = 0.05, I² = 0%]).

CONCLUSION

PUFA supplements appeared to improve CVD prognosis in patients receiving dialysis. Additional RCTs with longer follow-up periods need to clarify the benefits of PUFA supplements in this patient population.

Could Antioxidant Supplementation Delay Progression of Cardiovascular Disease in End-Stage Renal Disease Patients?

In end-stage renal disease patients, the leading causes of mortality are of cardiovascular (CV) origin. The underlying mechanisms are complex, given that sudden heart failure is more common than acute myocardial infarction. A contributing role of oxidative stress is postulated, which is increased even at early stages of chronic kidney disease, is gradually augmented in parallel to progression to endstage renal disease and is further accelerated by renal replacement therapy. Oxidative stress ensues when there is an imbalance between reactive pro-oxidants and physiologically occurring electron donating antioxidant defence systems. During the last decade, a close association of oxidative stress with accelerated atherosclerosis and increased risk for CV and all-cause mortality has been established. Lipid peroxidation has been identified as a trigger for endothelial dysfunction, the first step towards atherogenesis. In order to counteract the deleterious effects of free radicals and thereby ameliorate, or delay, CV disease, exogenous administration of antioxidants has been proposed. Here, we attempt to summarize existing data from studies that test antioxidants for CV protection, such as vitamins E and C, statins, omega-3 fatty acids and N-acetylcysteine.

Omega-3 Fatty Acids and Coronary Artery Disease: More Questions Than Answers

Studies show that patients with elevated triglycerides and well-controlled LDL levels under statin therapy still have a significant residual risk of cardiovascular (CV) events. Despite many attempts to reduce triglycerides with different hypolipidemic drugs, no therapeutic option has given satisfactory results so far. The initial enthusiasm that omega-3 fatty acids can effectively reduce triglycerides and CV risk was replaced with skepticism when the first large clinical trials failed to show any benefit in primary or secondary prevention. However, the latest studies succeeded in showing a positive effect of omega-3 fatty acids on CV outcome in patients with hypertriglyceridemia. The largest benefit was reported in secondary but not primary prevention. Interestingly, the reduction in triglycerides in some of these studies was disproportionately low to the relatively high CV risk reduction, which could indicate some other effects of omega-3 fatty acids that go well beyond hypotriglyceridemic action. This includes blood pressure reduction, antithrombotic effect, improvement of inflammatory status, endothelial function, and insulin resistance. Investigations also reported a significant and positive influence of omega-3 fatty acids on the composition and stabilization of coronary atherosclerotic plaques in patients with and without previous CV events. In addition to insufficiently known mechanisms of action and conflicting results about the effectiveness of omega-3 fatty acids, the safety problems, which include increased prevalence of atrial fibrillation and hemorrhage, were also reported. The aim of this clinical review was to summarize the current knowledge regarding the use of omega-3 fatty acids in CV patients, particularly those with coronary artery disease, and to present an overview of key clinical trial data.

Effect of omega-3 fatty acids supplementation on cardio-metabolic and oxidative stress parameters in patients with chronic kidney disease: a systematic review and meta-analysis

Background

Omega-3 fatty acids (FAs) have been suggested as a beneficial supplement in chronic kidney disease (CKD) patients, but the results of randomized clinical trials (RCTs) are controversial. We conducted a systematic review and meta-analysis to evaluate all the RCTs about the impact of omega-3 FAs supplementation on cardiometabolic outcomes and oxidative stress parameters in patients with CKD.

Methods

We performed a systematic database search in PubMed/MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane Central, up to May 2020. We included all placebo-controlled randomized trials that assessed the effect of omega-3 FAs supplementation on any cardiometabolic outcomes: blood pressure, total cholesterol (TC), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) or triglycerides (TG) and oxidative stress parameters. Data were pooled using DerSimonian–Laird’s random-effects model.

Results

Finally, thirteen articles met the inclusion criteria for this review omega-3 FAs supplementation significantly decrease TC (SMD: -0.26; 95% CI: − 0.51, − 0.02; I² = 52.7%), TG (SMD: -0.22; 95% CI: − 0.43, − 0.02; I² = 36.0%) and Malondialdehyde (MDA) levels (SMD: -0.91; 95% CI: − 1.29, − 0.54; I² = 00.0%) and also significantly increase superoxide dismutase (SOD) (SMD: 0.58; 95% CI: 0.27, 0.90; I² = 00.0%) and Glutathione peroxidase (GPx) (SMD: 0.50; 95% CI: 0.14, 0.86; I² = 00.0%) activities. However our results show that omega-3 FAs supplementation have no significant effects on HDL, LDL and blood pressure.

Conclusion

This systematic review and meta-analysis supports current evidence for the clinical benefit of omega-3 FAs intake to improve cardiometabolic parameters in CKD patients. However, well-designed RCTs still needed to provide a conclusive picture in this field.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02351-9.

Antioxidant Supplementation in Renal Replacement Therapy Patients: Is There Evidence?

The disruption of balance between production of reactive oxygen species and antioxidant systems in favor of the oxidants is termed oxidative stress (OS). To counteract the damaging effects of prooxidant free radicals, all aerobic organisms have antioxidant defense mechanisms that are aimed at neutralizing the circulating oxidants and repair the resulting injuries. Antioxidants are either endogenous (the natural defense mechanisms produced by the human body) or exogenous, found in supplements and foods. OS is present at the early stages of chronic kidney disease, augments progressively with renal function deterioration, and is further exacerbated by renal replacement therapy. End-stage renal disease patients, on hemodialysis (HD) or peritoneal dialysis (PD), suffer from accelerated OS, which has been associated with increased risk for mortality and cardiovascular disease. During HD sessions, the bioincompatibility of dialyzers and dialysate trigger activation of white blood cells and formation of free radicals, while a significant loss of antioxidants is also present. In PD, the bioincompatibility of solutions, including high osmolality, elevated lactate levels, low pH, and accumulation of advanced glycation end-products trigger formation of prooxidants, while there is significant loss of vitamins in the ultrafiltrate. A number of exogenous antioxidants have been suggested to ameliorate OS in dialysis patients. Vitamins B, C, D, and E, coenzyme Q10, L-carnitine, a-lipoic acid, curcumin, green tea, flavonoids, polyphenols, omega-3 polyunsaturated fatty acids, statins, trace elements, and N-acetylcysteine have been studied as exogenous antioxidant supplements in both PD and HD patients.

The Effect of Omega-3 Fatty Acids on Serum Apelin Levels in Cardiovascular Disease: A Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of mortality worldwide. Omega-3 fatty acids have been shown to have both anti-atherogenic and anti-inflammatory effects through inducing the expression and production of adipokines. Adipokines such as apelin, have been observed to play a protective role in the incidence and progression of CVD. The aim of this study was to assess the influence of omega-3 fatty acids supplementation on the serum apelin levels in patients with cardiovascular disease.

METHODS

Forty-six male patients with CVD participated in the study. Patients were randomly allocated into two groups receiving either omega-3 fatty acids or a placebo. Participants received 4 g of omega-3 fatty acids (EPA: 720 mg, DHA: 480 mg) or a placebo (edible paraffin) for 8 weeks. Serum apelin levels, high sensitive C-reactive protein (hs-CRP), and lipid profiles were measured. Dietary intake, anthropometric parameters, body composition, systolic and diastolic blood pressure were evaluated before and after the 8 weeks of intervention. Statistical analyses were performed using SPSS version 22.

RESULTS

Two participants from the placebo group withdrew from the study. Prior to the intervention, no significant differences were present between the two groups in age, body mass index, body composition, dietary intakes, lipid profiles and blood pressure. Compared to placebo, the intake of omega-3 fatty acids increased serum apelin levels (p= 0.018), decreased the levels of LDL cholesterol, and decreased serum hs-CRP concentrations (p= 0.007, p= 0.011 respectively). Additionally, the concentrations of VLDL, TG and hs-CRP (p= 0.037, p= 0.037 and p= 0.016 respectively) declined compared to baseline and final values in the omega-3 fatty acids group.

CONCLUSION

Omega-3 fatty acid supplementation increases serum apelin and HDL concentrations, while decreasing serum LDL-C and hs-CRP levels.

Update on the Impact of Omega 3 Fatty Acids on Inflammation, Insulin Resistance and Sarcopenia: A Review

Elderly and patients affected by chronic diseases face a high risk of muscle loss and impaired physical function. Omega 3 fatty acids (FA) attenuate inflammation and age-associated muscle loss, prevent systemic insulin resistance and improve plasma lipids, potentially impacting on sarcopenia. This paper aims to review recent randomized clinical studies assessing the effects a chronic omega 3 FA supplementation on inflammatory and metabolic profile during conditions characterized by sarcopenia (aging, insulin resistance, type 2 diabetes, chronic renal failure). A comprehensive search of three online databases was performed to identify eligible trials published between 2012 and 2017. A total of 36 studies met inclusion criteria. Omega 3 FA yielded mixed results on plasma triglycerides in the elderly and no effects in renal patients. No changes in systemic insulin resistance were observed. Inflammation markers did not benefit from omega 3 FA in insulin resistant and in renal subjects while decreasing in obese and elderly. Muscle related parameters improved in elderly and in renal patients. In conclusion, in aging- and in chronic disease-associated sarcopenia omega 3 FA are promising independently of associated anabolic stimuli or of anti-inflammatory effects. The evidence for improved glucose metabolism in insulin resistant and in chronic inflammatory states is less solid.

Changes in Bioavailability of Omega-3 (DHA) through Alpha-Tocopheryl Phosphate Mixture (TPM) after Oral Administration in Rats

Benefits of Omega-3 Docosahexaenoic acid (DHA) supplements are hindered by their poor solubility and bioavailability. This study investigated the bioavailability of various formulations of Omega-3 and tocopheryl phosphate mixture (TPM), following oral administration in rats, and assessed whether TPM could improve the oral absorption of DHA. The rats were administered with a high (265.7 mg/kg) or low dose (88.6 mg/kg) of DHA. TPM was examined at 1:0.1 w/w (low TPM dose) and 1:0.5 w/w (high TPM dose). Over 24 h, the DHA plasma concentration followed a TPM dose-dependent relationship, reflected in the higher mean Cmax values (78.39 and 91.95 μg/mL) and AUC values (1396.60 and 1560.60) for the low and high TPM, respectively. The biggest difference between the low dose DHA control (LDCont) and TPM formulations was at 4 h after supplementation, where the low and high TPM showed a mean 20% (ns) and 50% (p < 0.05) increase in DHA plasma concentrations versus the control formulation. After correcting for baseline endogenous DHA, the mean plasma DHA at 4 h produced by the LD-HTPM was nearly double (90%) the LDC control (p = 0.057). This study demonstrated that co-administering omega-3 with TPM significantly increases the bioavailability of DHA in the plasma, suggesting potential use for commercially available TPM + DHA fortified products.

Effect of Omega-3 Fatty Acids on Serum Lipid Profile and Oxidative Stress in Pediatric Patients on Regular Hemodialysis: A Randomized Placebo-Controlled Study

OBJECTIVE

We sought to evaluate the effects of omega-3 fatty acids supplementation on serum lipid profile and oxidative stress markers in pediatric patients with end-stage renal disease on regular hemodialysis (HD).

DESIGN

This study was a double-blinded, randomized, placebo-controlled trial conducted on 49 pediatric patients on regular HD for at least 6 months.

INTERVENTION

Patients were randomly divided into either omega-3 group (n = 25) who received 1-g oral omega-3 capsule once daily for 16 weeks or placebo group (n = 24) who received 1-g matching oral placebo capsule once daily for 16 weeks.

MAIN OUTCOME MEASURE

Lipid profile markers including: total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and oxidative stress markers including the following: malondialdehyde, glutathione peroxidase, and superoxide dismutase were measured at baseline and after 16 weeks of supplementation.

RESULTS

By the end of the study, children in omega-3 group showed a highly significant reduction in total cholesterol and a highly significant increase in glutathione peroxidase and superoxide dismutase levels.

CONCLUSION

The administration of omega-3 has a beneficial effect on serum lipid profile and oxidative stress in children undergoing HD.

Effect of omega-3 fatty acid supplementation on serum lipids and vascular inflammation in patients with end-stage renal disease: a meta-analysis

Omega-3 fatty acids (O3FAs) are associated with lower cardiovascular disease (CVD) risk in adults. However, this association in patients with end-stage renal disease (ESRD) remains controversial prompting the need for investigation into the role of O3FAs on serum lipids and vascular inflammation markers. The present meta-analysis summarized the effects of O3FA supplementation on serum lipids and vascular inflammatory markers in patients with ESRD. PubMed, EmBase, and the Cochrane Library were searched to identify randomized controlled trials (RCTs) focused on serum lipids and vascular inflammation markers in patients with ESRD. Standard mean differences (SMD) were used to measure the effect of O3FA supplementation on serum lipids and vascular inflammatory markers. The final pooled analysis included 20 RCTs involving 1,461 patients with ESRD. The results indicated that O3FA supplementation reduced TG by 0.61, LDL by 0.35 and CRP by 0.56. However, O3FA had no significant effect on TC, HDL, albumin, hemoglobin, homocysteine, DBP, glucose, lipoprotein(a), and ferritin. O3FA supplementation is associated with lower several serum lipids and vascular inflammation markers in patients with ESRD.