Eicosapantaenoic acid treatment based on the EPA/AA ratio in patients with coronary artery disease: follow-up data from the Tochigi Ryomo EPA/AA Trial in Coronary Artery Disease (TREAT-CAD) study

Circulating metabolites and coronary heart disease: a bidirectional Mendelian randomization

Background

Numerous studies have established a link between coronary heart disease and metabolic disorders. Yet, causal evidence connecting metabolites and Coronary Heart Disease (CHD) remains scarce. To address this, we performed a bidirectional Mendelian Randomization (MR) analysis investigating the causal relationship between blood metabolites and CHD.

Methods

Data were extracted from published genome-wide association studies (GWASs) on metabolite levels, focusing on 1,400 metabolite summary data as exposure measures. Primary analyses utilized the GWAS catalog database GCST90199698 (60,801 cases and 123,504 controls) and the FinnGen cohort (43,518 cases and 333,759 controls). The primary method used for causality analysis was random inverse variance weighting (IVW). Supplementary analyses included MR-Egger, weighted mode, and weighted median methods. Sensitivity analyses were conducted to evaluate heterogeneity and pleiotropy. Reverse MR analysis was employed to evaluate the direct impact of metabolites on coronary heart disease. Additionally, replication and meta-analysis were performed. We further conducted the Steiger test and colocalization analysis to reflect the causality deeply.

Results

This study identified eight metabolites associated with lipids, amino acids and metabolite ratios that may influence CHD risk. Findings include: 1-oleoyl-2-arachidonoyl-GPE (18:1/20:4) levels: OR = 1.08; 95% CI 1.04-1.12; P = 8.21E-06; 1-palmitoyl-2-arachidonoyl-GPE (16:0/20:4) levels: OR = 1.07; 95% CI 1.04-1.11; P = 9.01E-05; Linoleoyl-arachidonoyl-glycerol (18:2/20:4): OR = 1.08; 95% CI 1.04-1.22; P = 0.0001; Glycocholenate sulfate: OR = 0.93; 95% CI 0.90-0.97; P = 0.0002; 1-stearoyl-2-arachidonoyl-GPE (OR = 1.07; 95% CI 1.03-1.11; P = 0.0002); N-acetylasparagine (OR = 1.04; 95% CI 1.02-1.07; P = 0.0030); Octadecenedioate (C18:1-DC) (OR = 0.93; 95% CI 0.90-0.97; P = 0.0004); Phosphate to linoleoyl-arachidonoyl-glycerol (18:2-20:4) (1) ratio (OR = 0.92; 95% CI 0.88-0.97; P = 0.0005).

Conclusion

The integration of genomics and metabolomics offers novel insights into the pathogenesis of CHD and holds significant importance for the screening and prevention of CHD.

Omega-3 (n-3) Fatty Acid-Statin Interaction: Evidence for a Novel Therapeutic Strategy for Atherosclerotic Cardiovascular Disease

Managing atherosclerotic cardiovascular disease (ASCVD) often involves a combination of lifestyle modifications and medications aiming to decrease the risk of cardiovascular outcomes, such as myocardial infarction and stroke. The aim of this article is to discuss possible omega-3 (n-3) fatty acid-statin interactions in the prevention and treatment of ASCVD and to provide evidence to consider for clinical practice, highlighting novel insights in this field. Statins and n-3 fatty acids (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) are commonly used to control cardiovascular risk factors in order to treat ASCVD. Statins are an important lipid-lowering therapy, primarily targeting low-density lipoprotein cholesterol (LDL-C) levels, while n-3 fatty acids address triglyceride (TG) concentrations. Both statins and n-3 fatty acids have pleiotropic actions which overlap, including improving endothelial function, modulation of inflammation, and stabilizing atherosclerotic plaques. Thus, both statins and n-3 fatty acids potentially mitigate the residual cardiovascular risk that remains beyond lipid lowering, such as persistent inflammation. EPA and DHA are both substrates for the synthesis of so-called specialized pro-resolving mediators (SPMs), a relatively recently recognized feature of their ability to combat inflammation. Interestingly, statins seem to have the ability to promote the production of some SPMs, suggesting a largely unrecognized interaction between statins and n-3 fatty acids with relevance to the control of inflammation. Although n-3 fatty acids are the major substrates for the production of SPMs, these signaling molecules may have additional therapeutic benefits beyond those provided by the precursor n-3 fatty acids themselves. In this article, we discuss the accumulating evidence that supports SPMs as a novel therapeutic tool and the possible statin-n-3 fatty acid interactions relevant to the prevention and treatment of ASCVD.

Study protocol and baseline characteristics of Randomized trial for Evaluation in Secondary Prevention Efficacy of Combination Therapy-Statin and Eicosapentaenoic Acid: RESPECT-EPA, the combination of a randomized control trial and an observational biomarker study

BACKGROUND

Omega-3 polyunsaturated fatty acids (PUFAs) have been a hot topic since the Japan EPA Lipid Intervention Study (JELIS), the first landmark study using a highly purified eicosapentaenoic acid (EPA), indicated that EPA could decrease the incidence of cardiovascular events. Over 20 years have passed since the JELIS was conducted, and the standard treatment for dyslipidemia has altered significantly since then. The JELIS subjects did not undertake the current risk management especially current standard statins and did not exclusively target secondary prevention patients. In addition, the subjects included are relatively high EPA population. Furthermore, the clinical implication of the plasma EPA/arachidonic acid (AA) ratio as a biomarker has not yet been validated. Therefore, the Randomized trial for Evaluation in Secondary Prevention Efficacy of Combination Therapy - Statin and EPA (RESPECT-EPA) was planned and is currently underway in Japan.

METHODS

The RESPECT-EPA comprises two parts: the open-label randomized controlled trial (RCT) and biomarker study (prospective cohort study design). The RCT included patients with a low EPA/AA ratio. These patients were then randomized to highly purified EPA (1800 mg/day) or control groups. The primary endpoint was cardiovascular death, non-fatal myocardial infarction, non-fatal ischemic stroke, unstable angina pectoris, and clinically indicated coronary revascularization. The biomarker study assesses the EPA/AA ratio's usefulness as a biomarker for cardiovascular events prediction.

RESULTS

In the RCT, a total of 2,460 patients were enrolled in 95 sites in Japan. Patients' baseline characteristics were similar between intervention and control groups in the RCT. The baseline median EPA/AA ratio was 0.243 and 0.235, respectively. A total of 1,314 patients were participated in the observational part, and the baseline median EPA/AA ratio was 0.577.

CONCLUSIONS

After this study is completed, we will have further evidence on whether a highly purified EPA is effective in reducing cardiovascular events for secondary prevention or not, as well as whether if EPA/AA ratio is a predictor for future cardiovascular events. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN000012069).

Changes in the Eicosapentaenoic Acid to Arachidonic Acid Ratio in Serum over 10 Years in a Japanese Community: The Hisayama Study

AIM

Circulating omega-3 and omega-6 polyunsaturated fatty acids may to contribute to cardiovascular health at the population level. Over a decade, we investigated changes in the serum eicosapentaenoic acid (EPA) to arachidonic acid (AA) ratio, and in serum concentrations of the individual fatty acids, in a Japanese community.

METHODS

Community surveys took place in 2002-2003 and 2012-2013 in a rural area of Japan. The community surveys included 3,194 and 3,220 community dwellers aged ≥ 40 years who did not take EPA medication in 2002-2003 and 2012-2013, respectively. Fatty acid fractionations in serum were measured using a gas chromatography method. Changes in the serum EPA/AA ratio over time were examined using linear mixed models.

RESULTS

Overall, the average serum EPA/AA ratio decreased over the 10 years. A decreasing trend in the serum EPA/AA ratio occurred in all age groups except participants aged ≥ 80 years, with larger decreases in the younger age groups. A similar decline in serum EPA/AA ratio occurred in participants with and those without lipid-lowering therapy. Serum EPA concentrations were slightly increased in the whole population but remained stable or even decreased in participants aged 40-69. In contrast, the average serum AA concentrations increased in all age groups.

CONCLUSION

In a Japanese community, the serum EPA/AA ratio decreased over 10 years at the population level, especially in middle-aged participants.

Serum Oxylipin Profiles Identify Potential Biomarkers in Patients with Acute Aortic Dissection

Aortic dissection (AD) is a life-threatening cardiovascular disease with a dismal prognosis. Inflammation plays an important role in AD. Oxylipins are bioactive lipids involved in the modulation of inflammation and may be involved in the pathogenesis and progression of AD. This study aims to identify possible metabolites related to AD. A total of 10 type A Aortic dissection (TAAD) patients, 10 type B Aortic dissection (TBAD) patients and 10 healthy controls were included in this study. Over 100 oxylipin species were identified and quantified by liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis. Our investigation demonstrated substantial alterations in 91 oxylipins between AD and healthy individuals. Patients with TAAD had 89 entries accessible compared to healthy controls. According to orthogonal partial least squares discriminant analysis (OPLS-DA), fitness (R²X = 0.362 and R²Y = 0.807, p = 0.03) and predictability (Q² = 0.517, p = 0.005) are the validation parameters between the two groups. Using multivariate logistic regression, 13-HOTrE and 16(17)-EpDPE were the risk factors in the aortic patients group compared to healthy people (OR = 2.467, 95%CI:1.256–7.245, p = 0.035; OR = 0.015, 95%CI:0.0002–0.3240, p = 0.016, respectively). In KEGG enrichment of differential metabolites, the arachidonic acid metabolism pathway has the most metabolites involved. We established a diagnostic model in distinguishing between AD and healthy people. The AUC was 0.905. Oxylipins were significantly altered in AD patients, suggesting oxylipin profile is expected to exploit a novel, non-invasive, objective diagnosis for AD.

Eicosapentaenoic acid levels predict prognosis of peripheral artery disease caused by aortoiliac artery lesions

BACKGROUND AND AIM

Eicosapentaenoic acid (EPA) has been reported to improve clinical outcome of high-risk atherosclerotic patients. We investigated whether endogenous EPA values predict prognosis of peripheral artery disease (PAD) patients.

METHODS AND RESULTS

This retrospective study included 166 consecutive patients who had received endovascular therapy (EVT) for PAD caused by aortoiliac artery lesions. Patients were divided into 2 groups using median preoperative EPA value (57 μg/ml): LOW EPA (n = 83) and HIGH EPA (n = 83). We compared differences between the 2 groups in prevalence of major adverse limb events (MALE) which included target lesion revascularization (TLR), non-TLR, and major amputation, and major adverse events (MAE) which included MALE and all cause death. At a median follow-up period of 20 months, MALE had occurred in 24 LOW EPA patients (28.9%) and in 12 HIGH EPA patients (14.5%) (p = 0.04), and MAE had occurred in 41 LOW EPA patients (49.4%) and in 21 HIGH EPA patients (25.3%) (p < 0.01). Kaplan-Meier analysis showed prevalence of MALE and MAE was significantly higher in LOW EPA than in HIGH EPA (long-rank test χ² = 8.5, p < 0.01, log-rank test χ² = 13.2, p < 0.01, respectively). Multivariate Cox regression revealed preoperative EPA value < 57 μg/ml was an independent predictor for MALE (hazard ratio [HR]: 2.70; 95% CI: 1.35 to 5.4; p < 0.01) and MAE (HR: 2.86; 95% CI: 1.67 to 4.91; p < 0.01).

CONCLUSIONS

Endogenous EPA value seems to be associated with risk of MALE and MAE after EVT in patients with PAD caused by aortoiliac artery lesions.

Omega-3 polyunsaturated fatty acids focusing on eicosapentaenoic acid and docosahexaenoic acid in the prevention of cardiovascular diseases: a review of the state-of-the-art

INTRODUCTION

: An epidemiological study of Greenlandic Inuit suggested the importance of omega-3 polyunsaturated fatty acids (PUFAs) in preventing ischemic heart disease. After this landmark study, large-scale epidemiological studies have examined the benefits of omega-3 PUFAs in the prevention of cardiovascular diseases.

AREAS COVERED

: This article reviews studies on omega-3 PUFAs, and identifies issues relevant to cardiovascular risk.

EXPERT OPINION

: Recent studies have focused on the anti-inflammatory effects of omega-3 PUFAs and specialized pro-resolving mediators. High-purity eicosapentaenoic acid (EPA) ethyl ester and EPA/docosahexaenoic acid (DHA) preparations have been developed primarily for the treatment of hypertriglyceridemia. Various trials on the cardiovascular protective effects of omega-3 PUFAs have been reported, but the results have not been consistent. Some issues of the trials have been suggested, such as using low-dose omega-3 PUFAs and not including hypertriglyceridemia in subject selection criteria. REDUCE-IT study that used a high dose of high-purity EPA preparation showed a relative reduction in cardiovascular events, but, the STRENGTH study that used a high dose of EPA/DHA preparation did not support this benefit. This article reviews the roles of omega-3 PUFAs in cardiovascular diseases, including progress in understanding the molecular mechanisms and recent large-scale clinical trials.

The Anti-Inflammatory and Antioxidant Properties of n-3 PUFAs: Their Role in Cardiovascular Protection

Polyunsaturated fatty acids (n-3 PUFAs) are long-chain polyunsaturated fatty acids with 18, 20 or 22 carbon atoms, which have been found able to counteract cardiovascular diseases. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in particular, have been found to produce both vaso- and cardio-protective response via modulation of membrane phospholipids thereby improving cardiac mitochondrial functions and energy production. However, antioxidant properties of n-3 PUFAs, along with their anti-inflammatory effect in both blood vessels and cardiac cells, seem to exert beneficial effects in cardiovascular impairment. In fact, dietary supplementation with n-3 PUFAs has been demonstrated to reduce oxidative stress-related mitochondrial dysfunction and endothelial cell apoptosis, an effect occurring via an increased activity of endogenous antioxidant enzymes. On the other hand, n-3 PUFAs have been shown to counteract the release of pro-inflammatory cytokines in both vascular tissues and in the myocardium, thereby restoring vascular reactivity and myocardial performance. Here we summarize the molecular mechanisms underlying the anti-oxidant and anti-inflammatory effect of n-3 PUFAs in vascular and cardiac tissues and their implication in the prevention and treatment of cardiovascular disease.

The Effects of Lipid-Lowering Therapy on Serum Eicosapentaenoic Acid to Arachidonic Acid Ratio: An HIJ-PROPER Sub-Analysis

BACKGROUND

Controversy remains regarding the influence of lipid-lowering therapy on the eicosapentaenoic acid/arachidonic acid ratio.

OBJECTIVE

This study aimed to clarify the effects of lipid-lowering therapy on the eicosapentaenoic acid/arachidonic acid ratio in patients with acute coronary syndrome (ACS).

METHODS

This was a post hoc sub-analysis of the Heart Institute of Japan-PRoper level of lipid-lowering with pitavastatin and ezetimibe in ACS study. We compared the eicosapentaenoic acid/arachidonic acid ratio changes from baseline to the 3-month follow-up after contemporary lipid-lowering therapy with pitavastatin + ezetimibe therapy and pitavastatin mono-therapy.

RESULTS

Among patients with ACS and dyslipidemia, the eicosapentaenoic acid/arachidonic acid increased significantly in the pitavastatin mono-therapy group (0.40 ± 0.26 to 0.46 ± 0.34, P < .0001) but did not increase in the pitavastatin + ezetimibe group (0.37 ± 0.22 to 0.38 ± 0.27, P = .18). When the analysis was limited to patients who received 2 mg/day of pitavastatin during the follow-up period, these trends in changes of the eicosapentaenoic acid/arachidonic acid ratio remained unchanged. Multivariate analysis showed that ezetimibe use (P = .005; β = 0.09), ST-elevation myocardial infarction (P = .04; β = -0.01), and baseline low-density lipoprotein cholesterol (LDL-C) level (P = .0003; β = 0.12) were independent predictors of the percentage change in the eicosapentaenoic acid/arachidonic acid ratio. These trends were similar even when the analysis was limited to patients who did not take statins at enrollment.

CONCLUSION

Standard lipid-lowering therapy with pitavastatin mono-therapy improved the eicosapentaenoic acid/arachidonic acid ratio for patients with ACS. Intensive lipid-lowering therapy with pitavastatin + ezetimibe did not improve the eicosapentaenoic acid/arachidonic acid ratio, although LDL-C decreased significantly. Inhibition of the improvement in the eicosapentaenoic acid/arachidonic acid ratio by adding ezetimibe may affect cardiovascular disease prognosis.