Prevention of sudden cardiac death with omega-3 fatty acids in patients with coronary heart disease: A meta-analysis of randomized controlled trials

Aim. To systematically review trials concerning the effects of omega-3 fatty acids on sudden cardiac death (SCD), cardiac death, and all-cause mortality in coronary heart disease (CHD) patients.

Methods. PubMed, Embase, and the Cochrane database (1966–2007) were searched. We identified randomized controlled trials that compared dietary or supplementary intake of omega-3 fatty acids with control diet or placebo in CHD patients. Eligible studies had at least 6 months of follow-up data, and cited SCD as an end-point. Two reviewers independently assessed methodological quality. Meta-analysis of relative risk was carried out using the random effect model.

Results. Eight trials were identified, comprising 20,997 patients. In patients with prior myocardial infarction (MI), omega-3 fatty acids reduced relative risk (RR) of SCD (RR = 0.43; 95% CI: 0.20–0.91). In patients with angina, omega-3 fatty acids increased RR of SCD (RR = 1.39; 95% CI: 1.01–1.92). Overall, RR for cardiac death and all-cause mortality were 0.71 (95% CI: 0.50–1.00) and 0.77 (95% CI: 0.58–1.01), respectively.

Conclusions. Dietary supplementation with omega-3 fatty acids reduces the incidence of sudden cardiac death in patients with MI, but may have adverse effects in angina patients.     

Treatment of hypertriglyceridemia with omega-3 fatty acids: a systematic review

PURPOSE: To (a) critically appraise available randomized controlled trials (RCTs) addressing the efficacy of long-chain omega-3 fatty acids as secondary agents for prevention of hypertriglyceridemia and (b) make recommendations for clinical practice. DATA SOURCES: Two independent reviewers examined all RCTs from 1994 to 2003 identified in several databases, extracted data from each study, and used the previously tested Boyack and Lookinland Methodological Quality Index (MQI) to determine study quality. CONCLUSIONS: Ten studies reported long-chain omega-3 fatty acids to be effective in the treatment of hypertriglyceridemia. The average decrease in triglycerides was 29%, total cholesterol 11.6%, very low density lipoprotein (VLDL) 30.2%, and low-density lipoprotein (LDL) 32.5%. One study found LDLs to increase by 25%. The average increase in high-density lipoprotein was 10%. The overall average MQI score was 36% (range = 26% to 54%). Many of the RCTs had serious shortcomings, including short duration, lack of a power analysis, no intention-to-treat analysis, no report of blind assessment of outcome, and lack of dietary control as a confounding variable. IMPLICATIONS FOR PRACTICE: Overall study methodology was weak. Although the evidence supporting use of long-chain omega-3 fatty acids in the secondary prevention of hypertriglyceridemia is reasonably strong, until there are larger RCTs of better methodological quality, it is not recommended that practitioners treat hypertriglyceridemia with omega-3 fatty acid supplementation in lieu of lipid-lowering medications.     

Effect of omega-3 supplements on plasma apolipoprotein C-III concentrations: a systematic review and meta-analysis of randomized controlled trials

Abstract

Background: Apolipoprotein C-III (apo C-III) is a key regulator of triglycerides metabolism. The aim of this meta-analysis was to assess the effect of fish omega-3 polyunsaturated fatty acids (PUFAs) on apo C-III levels.

Methods: Randomized placebo-controlled trials investigating the impact of omega-3 on apo C-III levels were searched in PubMed-Medline, SCOPUS, Web of Science and Google Scholar. A random-effects model and generic inverse variance method were used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. A weighted random-effects meta-regression was performed to evaluate the impact of potential confounders on glycemic parameters.

Results: This meta-analysis comprising 2062 subjects showed a significant reduction of apo C-III concentrations following treatment with omega-3 (WMD: ?22.18?mg/L, 95% confidence interval: ?31.61, ?12.75, p?<?.001; I²: 88.24%). Subgroup analysis showed a significant reduction of plasma apo C-III concentrations by eicosapentaenoic acid (EPA) ethyl esters but not omega-3 carboxylic acids or omega-3 ethyl esters. There was a greater apo C-III reduction with only EPA as compared with supplements containing EPA and docosahexaenoic acid (DHA) or only DHA. A positive association between the apo C-III-lowering effect of omega-3 with baseline apo C-III concentrations and treatment duration was found.

Conclusions: This meta-analysis has shown that omega-3 PUFAs might significantly decrease apo C-III.

• Key messages

• Omega-3 PUFA supplements significantly reduce apo C-III plasma levels, particularly in hypertriglyceridemic patients when applied in appropriate dose (more than 2?g/day)

• Triglyceride (TG)-lowering effect is achieved via peroxisome proliferator-activated receptors α

• Further studies should address the effect of omega-3 PUFAs alone or with other lipid-lowering drugs in order to provide a final answer whether apo C-III could be an important target for prevention of cardiovascular disease

• New apo C-III antisense oligonucleotide drug (Volanesorsen) showed to be promising in decreasing elevated TGs by reducing levels of apo C-III mRNA

     

Effects of combination treatment with policosanol and omega-3 fatty acids on platelet aggregation: A randomized, double-blind clinical study

Background:

Policosanol is a mixture of long-chain primary aliphatic alcoholspurified from sugar cane wax that has cholesterol lowering and antiplatelet effects. Omega-3 fatty acids (FA) have triglyceride lowering and antiplatelet effects. Combination treatment with policosanol and omega-3 FA (Ω23FA) has been associated with significant inhibition of platelet aggregation in rabbits compared with either drug alone.

Objective:

The aim of this study was to investigate the effects of combination treatment with Ω3FA (1 g/d) and policosanol (Ω3FA+Poli) compared with Ω3FA (1 g/d) plus placebo (Ω3FA+Pla) on platelet aggregation in human patients with hypercholesterolemia.

Methods:

This randomized, double-blind, clinical study at the Surgical Medical Research Center (Havana City, Cuba) recruited outpatients from lipid clinics, with some atherosclerotic risk factors. Outpatients of both sexes aged 20 to 75 years with serum total cholesterol (TC) levels ≥5 and <6 mmol/L were eligible to enroll. They were included in the study at the end of a 4-week diet stabilization period if their platelet aggregation to arachidonic acid (AA) was ≥50% and serum TC level remained ≥5 mmol/L. Patients were then evenly randomized to receive Ω3FA (1 g/d) + placebo or Ω3FA (1 g/d) + policosanol (10 mg/d) to be taken PO with the evening meal for 21 days. Treatment was assigned according to a randomization code using balanced blocks and a 1:1 allocation ratio. Inhibition of platelet aggregation to AA was the primary efficacy variable, while effects on platelet aggregation to collagen and epinephrine and on lipid profile were secondary variables. Drug compliance and adverse events (AEs) were monitored. Tolerability was assessed using physical examinations and laboratory test results.

Results:

Sixty-four subjects were initially enrolled. Fifty-four patients (30 women, 24 men; mean [SD] age, 58.4 [12] years, [range, 40-70 years]) met the inclusion criteria and were randomized to treatment; 2 groups of 27. After 21 days, platelet aggregation to AA was significantly inhibited in the 2 groups. Ω3FA+Poli inhibited platelet aggregation to all agonists by ≥20%. Platelet aggregation to AA 1.0 and 1.5 mM was inhibited with combination treatment (39.6% and 33.9%, respectively; both P < 0.001 vs baseline; P < 0.001 and P < 0.01, respectively, vs Ω3FA+Pla) and with Ω3FA+Pla (11.0% and 13.3%; both, P < 0.001). Combination treatment was more effective in inhibiting platelet aggregation to AA 1.0 and 1.5 mM in 28.6% (P < 0.001) and 20.6% (P < 0.01), respectively. Platelet aggregation to collagen 1 μg/mL was significantly inhibited with combination treatment and with Ω3FA+Pla compared with baseline (43.2% and 15.1%, respectively; both, P < 0.001), but the effects of combination treatment were significantly greater (P < 0.01). Platelet aggregation to epinephrine 0.1 mM was inhibited with Ω3FA+Poli and Ω3FA+Pla (34.8% and 20.1%; both, P < 0.001), with similar results for both groups. Bleeding time did not change significantly for either group and Ω3FA+Pla did not significantly change the lipid profile. Combination treatment did significantly reduce levels of low-density lipoprotein cholesterol (LDL-C) (17.4%; P < 0.001 vs baseline, P < 0.05 vs Ω3FA+Pla) and TC (10.1%; P < 0.001 vs baseline, P < 0.05 vs Ω3FA+Pla), increase high-density lipoprotein cholesterol (HDL-C) levels (18.0%; P < 0.001 vs baseline), but did not significantly change triglyceride levels. Three patients (2 from the Ω3FA+Poli group and 1 from the Ω3FA+Pla group) withdrew from the trial, though none were due to AEs. Two patients receiving combination treatment reported mild AEs (headache). All treatments were well tolerated.

Conclusions:

In these patients, policosanol (10 mg/d) administered concomitantly with Ω3FA (1 g/d) enhanced the inhibition of platelet aggregation to AA and collagen, but not to epinephrine, compared with Ω3FA+Pla, without significantly affecting bleeding time. Concomitant treatment was also associated with reduced levels of LDL-C and TC and raised HDL-C levels. All treatments were well tolerated.     

ω-3多不饱和脂肪酸对急性呼吸窘迫综合征患者血清炎症介质的影响

目的观察ω-3多不饱和脂肪酸对急性呼吸窘迫综合征（ARDS）患者血清炎症介质释放的影响。方法将42例ARDS患者按随机化数字表原则,分为对照组和研究组,每组各21例。两组患者均接受等氮、等热量的全胃肠外营养,热量25kcal·kg^-1·d^-1、氮摄入量0.2g/kg,其中研究组加用ω-3多不饱和脂肪酸（0.2g·kg^-1·d^-1）,共7d。分别检测治疗前和治疗后第1、3、7天血清白细胞介素1（IL-1）、IL-6、肿瘤坏死因子α（TNF-α）水平,并观察动脉血氧分压和氧合指数的变化。结果加用ω-3多不饱和脂肪酸治疗后,研究组在不同时间点IL-1、IL-6、TNF-α均明显低于对照组（P均〈0.05）;两组患者动脉血氧分压和氧合指数均有改善,且研究组氧合指数较高,差异均有统计学意义（P均〈0.05）。结论ω-3多不饱和脂肪酸可降低ARDS患者IL-1、IL-6、TNF-α水平,在一定程度上有利于ARDS患者呼吸功能的恢复。     

Fish oils in the care of coronary heart disease patients: a meta-analysis of randomized controlled trials

What is the place of fish oils in the care of coronary heart disease (CHD) patients? As several clinical trials have already addressed this question without giving definitive answers, we did a meta‐analysis of trials regarding the efficacy of omega‐3 fatty acids in preventing cardiovascular mortality and morbidity. We searched the MEDLINE (1966–2003), EMBASE databases, proceedings abstracts and references of reviewed articles. Randomized controlled trials (RCTs) of the efficacy of omega‐3 fatty acids among adults with recent or acute myocardial infarction (MI), or angina were selected. Two reviewers abstracted data independently. Five relevant outcomes, mortality from all causes, fatal and non‐fatal MI, non‐fatal stroke and angina, were measured. Data were synthesized using a fixed effect model. Ten RCTs with 14 727 patients were included. No significant heterogeneity was detected. Daily intake of omega‐3 fatty acids for a mean duration of 37 months decreased all causes of mortality by 16% (relative risk 0.84, 95% confidence interval [0.76; 0.94]) and the incidence of death due to MI by 24% (0.76, [0.66; 0.88]). No significant effect was found for the other outcomes. Because of the suboptimal quality of the studies included into the meta‐analysis and the absence of data in patients receiving statins, these results do not justify adding fish oils systematically to the heavy pharmaceutical assortment already recommended in CHD patients.     

Bariatric surgery reduces fasting total fatty acids and increases n-3 polyunsaturated fatty acids in morbidly obese individuals

Background: Obesity is a global pandemic leading to increased mortality and increased risk of cardiovascular disease. Bariatric surgery is an established treatment of obesity leading to weight loss and reduction of mortality. To further elucidate how bariatric surgery improves metabolic control, we explored the fatty acid (FA) profiles in morbidly obese subjects treated with lifestyle intervention and subsequent bariatric surgery.

Methods: The intervention group consisted of 34 morbidly obese patients scheduled for bariatric surgery and the control group of 17 non-obese patients scheduled for elective laparoscopic procedures. The intervention group had to undergo lifestyle changes preoperatively. Fasting blood samples were drawn at admission, after lifestyle intervention and 1 year after bariatric surgery.

Results: At admission, the morbidly obese patients had significantly higher levels of monounsaturated FAs (MUFAs) and lower levels of n-6 polyunsaturated FAs (PUFAs) and n-3 PUFAs than healthy controls (all p-values <.05). In the intervention group, there was a significantly lower level of total FAs after lifestyle intervention, and from admission to 1 year after surgical intervention (both, p?<?.05), primarily reflecting a lower proportion of saturated FAs (SFAs). Following bariatric surgery, but not after lifestyle changes, there was an increase in the proportion of n-3 PUFA (p?<?.05) reaching levels not significantly different from healthy controls.

Conclusions: Our findings suggest that a reduced proportion of the proposed anti-atherogenic n-3 PUFAs characterizes morbidly obese individuals, and that this FA profile is reversed by bariatric surgery, but not by lifestyle intervention.     

The effect of green coffee extract supplementation on anthropometric measures in adults: A comprehensive systematic review and dose-response meta-analysis of randomized clinical trials

Background and aimTwo meta-analyses summarized data on the effects of green coffee extract (GCE) supplementation on anthropometric measures. However, the accuracy of those meta-analyses is uncertain due to several methodological limitations. Therefore, we aimed to conduct a comprehensive systematic review and dose-response meta-analysis to summarize all available evidence on the effects of GCE supplementation on anthropometric measures by considering the main limitations in the previous meta-analyses.MethodsWe searched available online databases for relevant publications up to January 2020, using relevant keywords. All randomized clinical trials (RCTs) investigating the effects of GCE supplementation, compared with a control group, on anthropometric measures [including body weight, body mass index (BMI), body fat percentage, waist circumference (WC) and waist-to-hip ratio (WHR)] were included.ResultsAfter identifying 1871 studies from our initial search, 15 RCTs with a total sample size of 897 participants were included in the systematic review and meta-analysis. We found a significant reducing effect of GCE supplementation on body weight (weighted mean difference (WMD): −1.23, 95 % CI: −1.64, −0.82 kg,P < 0.001), BMI (WMD: −0.48, 95 % CI: −0.78, −0.18 kg/m², P = 0.001), and WC (WMD: −1.00, 95 % CI: −1.70, −0.29 cm, P = 0.006). No significant effect of GCE supplementation on body fat percentage and WHR was seen. In the dose-response analyses, there was no significant association between chlorogenic acid (CGA) dosage, as the main polyphenol in green coffee, and changes in anthropometric measures.ConclusionWe found that GCE supplementation had a beneficial effect on body weight, BMI and WC. It provides a cost-effective and safe alternative for the treatment of obesity. Additional well-designed studies are required to further confirm our findings.     

The effects of carnitine supplementation on clinical characteristics of patients with non-alcoholic fatty liver disease: A systematic review and meta-analysis of randomized controlled trials

ObjectiveThe beneficial effects of carnitine supplementation on nonalcoholic fatty liver disease are unclear. We conducted a systematic review and meta-analysis to evaluate the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance in patients with nonalcoholic fatty liver disease.MethodsA comprehensive search of PubMed, Web of Science, Scopus, Cochrane Library, and Google Scholar databases were performed. Only randomized placebo-controlled human studies that examined the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance up to September 2019 were included. Fixed effects or random-effects models were applied to compute the pooled effect size. Heterogeneity assessments were performed using Cochran’s Q test and I-squared statistics. The quality of the studies was assessed using the Jaded scale.ResultsA total of 5 articles were selected, including 334 individuals (167 in control and 167 in intervention groups). The results demonstrated that carnitine supplementation significantly reduced homeostasis model assessment of insulin resistance (HOMA-IR) (WMD: −0.91; 95 % CI: −1.11, −0.72; p < 0.001, I² = 0.0 %) and the levels of aspartate aminotransferase (AST) (WMD: −16.62; 95 % CI: −28.11, −5.14; IU/l; p = 0.005, I² = 93.5 %), alanine aminotransferase (ALT) (WMD: -33.39; 95 % CI: −45.13, −21.66; IU/l; p < 0.001, I² = 93.4 %), and triglycerides (TG) (WMD: −22.13; 95 % CI: −38.91, −5.34; mg/dl; p = 0.01; I² = 0.0 %). However, the results of the pooled effect size did not show any significant effect of carnitine supplementation on body mass index (BMI) (WMD: 0.07; 95 % CI: −0.15, 0.29; p = 0.55; I² = 0.0 %), body weight (WMD: −0.28; 95 % CI: −2.23, 1.68; p = 0.78; I² = 45.7 %), the levels of gamma-glutamyl transferase (γGT) (WMD: −11.31; 95 % CI: −24.35, 1.73; IU/l; p = 0.09, I² = 61.1 %), cholesterol (WMD: −13.58; 95 % CI: −46.77, 19.60; mg/dl; p = 0.42; I² = 94.9 %), high-density lipoprotein-cholesterol (HDL-C) (WMD: 1.36; 95 % CI: −0.96, 3.68; mg/dl; p = 0.25; I² = 64.7 %), and low density lipoprotein-cholesterol (LDL-C) (WMD: −14.85; 95 % CI: −45.43, 15.73; mg/dl; p = 0.34; I² = 96.4 %).ConclusionsThis analysis shows that carnitine supplementation for patients with nonalcoholic fatty liver disease demonstrates a reduction in AST, ALT, TG levels and HOMA-IR. However, no significant effect of carnitine supplementation was observed on BMI, body weight, the levels of γGT, TC, HDL-cholesterol and LDL-cholesterol.     

Effects of berberine and barberry on anthropometric measures: A systematic review and meta-analysis of randomized controlled trials

ObjectiveDespite controversies, no study has systematically summarized findings from earlier studies on the effect of berberine and barberry on anthropometric measures. Therefore, the current systematic review and meta-analysis was conducted on the effect of berberine and barberry on body mass index (BMI), body weight (BW), waist circumference (WC) and waist-hip ratio (WHR) in adults.MethodsRelevant studies, published up to August 2019, were searched through PubMed/Medline, Scopus, ISI Web of Science, Embase and Google Scholar. All randomized clinical trials investigating the effect of berberine and barberry on the anthropometric measures including BMI, BW, WC or/and WHR were included.ResultsOut of 252 citations, 12 trials that enrolled 849 subjects were included. Berberine and barberry resulted in no significant change in BMI (Weighted mean differences (WMD): -0.16 kg/m²; 95 % CI: -0.43 to 0.11, P = 0.247), BW (WMD: −0.11 kg; 95 % CI: −0.13 to 0.91, P = 0.830), and berberine resulted in not significant in WC (WMD: −0.58 cm; 95 % CI: −1.89 to 0.72, P = 0.379) and significant reduction in WHR (WMD: -0.03; 95 % CI: −0.04 to -0.01, P < 0.0001).ConclusionWe found a significant reduction in WHR following berberine consumption in adults. Further clinical trials with high quality according to challenges mentioned seem to be helpful to use berberine and barberry as a supplement for certain health conditions, efficiently.     

Effects of walnut intake on anthropometric characteristics: A systematic review and dose-response meta-analysis of randomized controlled trials

Background & objectiveEffects of walnut intake on anthropometric measurements have been inconsistent among clinical studies. Thus, we conducted a meta-analysis of randomized clinical trials (RCTs) to evaluate and quantify the effects of walnut intake on anthropometric characteristics.MethodsWe carried out a systematic search of all available RCTs up to June 2019 in the following electronic databases: PubMed, Scopus, Web of Science and Google Scholar. Pooled weight mean difference (WMD) of the included studies was estimated using random-effects model.ResultsA total of 27 articles were included in this meta-analysis, with walnuts dosage ranging from 15 to 108 g/d for 2 wk to 2 y. Overall, interventions with walnut intake did not alter waist circumference (WC) (WMD: -0.193 cm, 95 % CI: -1.03, 0.64, p = 0.651), body weight (BW) (0.083 kg, 95 % CI: -0.032, 0.198, p = 0.159), body mass index (BMI) (WMD: -0.40 kg/m,²95 % CI: -0.244, 0.164, p = 0.703), and fat mass (FM) (WMD: 0.28 %, 95 % CI: -0.49, 1.06, p = 0.476). Following dose-response evaluation, reduced BW (Coef.= -1.62, p = 0.001), BMI (Coef.= -1.24, p = 0.041) and WC (Coef.= -5.39, p = 0.038) were significantly observed through walnut intake up to 35 g/day. However, the number of studies can be limited as to the individual analysis of the measures through the dose-response fashion.ConclusionsOverall, results from this meta-analysis suggest that interventions with walnut intake does not alter BW, BMI, FM, and WC. To date, there is no discernible evidence to support walnut intake for improving anthropometric indicators of weight loss.     

Maternal erythrocyte omega-3 and omega-6 fatty acids, and plasma lipid concentrations, are associated with habitual dietary fish consumption in early pregnancy

OBJECTIVES: We investigated the relationship between selected maternal erythrocyte omega-3 and omega-6 polyunsaturated fatty acids (PUFA) and plasma lipids in early pregnancy and reported habitual fish consumption during the periconceptional period. DESIGN AND METHODS: This cohort study included 923 pregnant women who reported periconceptional dietary habits and provided a blood sample before 20 weeks of gestation. PUFA was determined by gas chromatography and plasma lipids by standard enzymatic methods. Differences in erythrocyte PUFA and plasma lipid concentrations were estimated using linear regression. RESULTS: Mean erythrocyte eicosapentanoic acid and other PUFA content (%/total) were positively associated with frequency of self-reported fish consumption. Arachidonic acid was inversely related with frequent fish consumption (p trend <0.001). Women who consumed fish >twice/week had lower plasma triglyceride (-11.5 mg/dl) and higher HDL-cholesterol (+2.8 mg/dl) concentrations than women consuming fish 相似文献   

Effects of pro-/synbiotic supplementation on anthropometric and metabolic indices in overweight or obese children and adolescents: A systematic review and meta-analysis

Background & aimsExisting evidence on the possible effects of pro-/synbiotics on overweight or obese children and adolescents has not been fully established. Therefore, the present review was undertaken to evaluate the overall effects of pro-/synbiotics supplementation on anthropometric indices and metabolic indices in overweight or obese children and adolescents.MethodsA systematic computerized literature search of PubMed, Scopus, ISI Web of science and Google Scholar databases was conducted up to November 2018. All RCTs using pro-/synbiotics supplements in overweight or obese children and adolescents included in this systematic review and meta-analysis.ResultsOverall 9 randomized trials including 410 subjects were identified for the present meta-analysis. Pooled analysis did not illustrate any significant changes in BMI z-score, waist circumference, weight, body fat, fasting blood sugar and lipid profiles (triglyceride, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol) after supplementation with pro-/synbiotics for 4–16 weeks. However, subgroup analysis by intervention type revealed a significant reduction of BMI z-score in synbiotic subgroups.ConclusionBased on our findings, modulation of gut microbiota composition through pro-/ synbiotic supplements did not have favorable effects to manage overweight or obese children and adolescents. Further large-scale studies are warranted to confirm present findings.     

Positive zinc intake and a Japanese diet rich in n-3 fatty acids induces clinical remission in patients with mild active ulcerative colitis: a randomized interventional pilot study

Zinc intake has reduced hospitalizations in patients with ulcerative colitis (UC), highlighting the need to maintain blood zinc levels. This prospective study investigated whether the promotion of zinc intake and a Japanese diet (high in n-3 fatty acids) could induce clinical remission in patients with mild active UC. Patients with mild active UC were randomly assigned to either (1) continue an unrestricted diet or (2) receive nutritional guidance promoting zinc intake and a Japanese diet. The primary endpoint was clinical remission at 24 weeks. Secondary endpoints were the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) scores, Clinical Activity Index (CAI), Geboes Histopathology Score (GHS), and biomarkers, including zinc levels, measured at 12 and 24 weeks. Nutritional assessments were performed using the Food Frequency Questionnaire. The CAI, UCEIS, and GHS scores were significantly lower in the intervention group than in the control group, with a significantly higher proportion of patients achieving clinical remission. Furthermore, the intervention group exhibited weight gain and significantly increased blood zinc levels. The combination of promoting dietary zinc intake and a Japanese diet rich in n-3 fatty acids can induce clinical remission in patients with mild active UC.     

Enteral omega-3 fatty acid supplementation in adult patients with acute respiratory distress syndrome: a systematic review of randomized controlled trials with meta-analysis and trial sequential analysis

Purpose

Controversy remains as to whether enteral supplementation of ω-3 fatty acids (FA) could improve outcomes in patients with acute respiratory distress syndrome (ARDS). Thus, we did a meta-analysis and aimed to investigate the benefit and harm of enteral ω-3 FA supplementation in adult patients with ARDS.

Methods

Databases including PubMed, Embase, the Cochrane Register of Controlled Trials, and Google Scholar were searched to find relevant articles. Randomized controlled trials (RCTs) comparing enteral ω-3 FA supplementation with a control or placebo intervention in adult patients with ARDS were included. The primary outcome was all-cause 28-day mortality. We used the Cochrane Collaboration methodology.

Results

Seven RCTs with 955 adult patients qualified for inclusion, and all the selected trials were considered as at high risk of bias. The use of enteral ω-3 FA did not significantly reduce all-cause 28-day mortality [relative risk (RR), 0.90; 95 % confidence intervals (CI), 0.68–1.18; p = 0.44; I ² = 31 %; random effects]. Trial sequential analysis indicated lack of firm evidence for a 20 % RR reduction in all-cause 28-day mortality. PaO₂/FiO₂ ratio was significantly increased in the ω-3 FA group on day 4 [weighted mean difference (WMD), 45.14; 95 % CI, 16.77–73.51; p = 0.002; I ² = 86 %; random effects] and day 7 (WMD, 33.10; 95 % CI, 1.67–64.52; p = 0.04; I ² = 88 %; random effects). Meta-analysis using a random effects model showed no significant differences in ventilator-free days (VFD) (WMD, 2.47 days; 95 % CI, ?2.85 to 7.79; p = 0.36; I ² = 91 %) or intensive care unit-free days (ICU) (WMD, 2.31 days; 95 % CI, ?2.34 to 6.97; p = 0.33; I ² = 89 %) between the two groups.

Conclusions

Among patients with ARDS, enteral supplementation of ω-3 FA seemed ineffective regarding all-cause 28-day mortality, VFD, and ICU-free days. Routine use of enteral ω-3 FA cannot be recommended based on the available evidence.     

鱼油预防心血管疾病的系统评价

目的系统评价鱼油（n-3多不饱和脂肪酸）防治心血管疾病的效果。方法计算机检索PubMed、Cochrane图书馆临床对照试验资料库（2009年第1期）、CBM、CNKI、万方等数据库,同时筛检了纳入文献的参考文献,按纳入与排除标准纳入鱼油在心血管疾病防治方面的随机对照试验。由两名评价员独立评价文献质量、提取资料并交叉核对,如遇分歧讨论解决。而后采用RevMan4.2软件对资料进行Meta分析。结果共纳入5项研究,包括37689例研究对象。Meta分析结果显示：①与安慰剂组比较,鱼油可降低心血管性死亡事件[RR=0.91,95%CI（0.84,0.98）]、总心血管事件[RR=0.95,95%CI（0.91,0.98）]、心肌梗死[RR=0.79,95%CI（0.65,0.96）]和心绞痛[RR=0.79,95%CI（0.64,0.96）]的发生率;②在降低心血管疾病住院率、全因死亡事件、猝死及心衰发生率方面,与安慰剂比较差异无统计学意义（P〉0.05）;③在心律失常[RR=1.14,95%CI（0.80,1.62）]和卒中发生率[RR=1.12,95%CI（0.97,1.30）]方面,与安慰剂比较有轻度升高,但差异均无统计学意义（P〉0.05）。结论鱼油能降低总心血管事件、总心血管性死亡、心肌梗死及心绞痛的发生率。在全因死亡事件、猝死、心衰及心血管疾病住院事件方面疗效不明显,而在心律失常及卒中方面发生率有轻度升高但无统计学意义。结果表明鱼油在高危人群中防治心血管疾病可获益。     

Failure of omega-3 polyunsaturated fatty acids in prevention of migraine: a double-blind study versus placebo

Omega-3 polyunsaturated fatty acids (OPFA) have beneficial effects on inflammatory reactions and production of cytokines. They decrease the release of 5HT by platelets and possess vasorelaxant activity. This led them to be tried in the prophylactic treatment of migraine. After 4 weeks of a single-blind placebo run-in period, patients were randomized and treated in double-blind condition by placebo or OPFA 6 g a day for 16 weeks, followed by a 4-week placebo run-out period. The intention to treat population included 196 patients. Those who received all four treatment periods included 96 patients taking OPFA and 87 taking placebo. The primary efficacy analysis was the number of migraine attacks during the last 4 weeks of treatment. During this period, the mean number of attacks was 1.20 +/- 1.40 in the OPFA group and 1.26 +/- 1.11 in the placebo group (NS). The total number of attacks during the 4-month period of the study was significantly different between groups: 7.05 in the placebo group, 5.95 in the OPFA group (P = 0.036). Mean intensity, mean duration of the attacks and rescue medication use, were not significantly different between the two groups. Except for a significant difference against OPFA for eructations, the tolerance was satisfying. Despite a run-in placebo period of 1 month, a very strong placebo effect was observed in this trial: 45% reduction of the attacks between run-in and 4-month treatment period (55% in the OPFA group, P = 0.058). Finally, this large study did not confirm two previous studies based on a small number of patients.     

The limited effect of omega-3 polyunsaturated fatty acids on cardiovascular risk in patients with impaired glucose metabolism: A meta-analysis

Objectives

The impacts of marine-derived n − 3 polyunsaturated fatty acids (n − 3 PUFAs) on cardiovascular risk are not well known. We conducted this meta-analysis to determine the effects of n − 3 PUFAs on cardiovascular outcomes and cardiovascular risk markers in patients with impaired glucose metabolism (IGM).

Design and methods

We searched PUBMED, EMBASE, The Cochrane Library and reference lists of relevant papers for high quality randomized controlled trials comparing dietary intake of n − 3 PUFAs with placebo in IGM patients. Data was extracted and quality assessed independently by two reviewers. Authors were contacted for missing information. Overall estimates were calculated using a random-effects model or a fixed-effects model, and the possibility of publication bias was examined using a funnel plot. Subgroup analyses were conducted to explore the association between the risk markers and study characteristics.

Results

Our meta-analysis included 19 studies, 24,788 patients. Compared with placebo, n − 3 PUFAs had no statistically significant reduce effect on cardiovascular mortality, major cardiovascular events, all-cause mortality or composite endpoint of all-cause mortality or hospitalization for cardiovascular cause, however it can significantly reduce the level of triglycerides (weighted mean difference [WMD] − 0.25 mmol/L; 95% CI − 0.37 to − 0.13: p < 0.001; 12 trials, 13,921 patients).

Conclusion

Marine-derived n − 3 polyunsaturated fatty acids have no protective effect on cardiovascular mortality, major cardiovascular events, all-cause mortality and composite endpoint of all-cause mortality or hospitalization for cardiovascular cause in IGM patients, but can reduce triglyceride level.