Linoleic Acid in Adipose Tissue and Development of Ischemic Stroke: A Danish Case-Cohort Study

Deciphering the effective components of a TCM formula for atherosclerosis by three-dimensional pattern recognition of exogenous components correlated with endogenous metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

The deciphering of effective components is crucial for understanding the role they play and how they function in traditional Chinese medicine (TCM) formulae. However, this remains a significant challenge for these complex systems with multiple components, targets, and pathways, despite their therapeutic benefits.

AIM OF THE STUDY

Three-dimensional pattern recognition of exogenous components correlated with endogenous metabolites was proposed to discover the effective components of Gualou-Xiebai-Banxia decoction (GXB), a famous classical TCM formula for effective improvement of atherosclerosis (AS).

MATERIALS AND METHODS

The potential effective exogenous components were determined by three-dimensional pattern recognition of abundance, bioavailability and AS-related activity. The efficacy of GXB in attenuating AS was evaluated using an Apolipoprotein E-deficient (ApoE-/-) mice model subjected to a high-fat diet regimen. Plasma metabolomics was developed to dig out GXB efficacy-related endogenous metabolites. Next, the potential effective exogenous components and GXB efficacy-related endogenous metabolites were combined with AS targets to develop correlation analysis, so as to explore candidate effective components and potential mechanisms of GXB. Further, the effective components were validated by oxidized low-density lipoprotein-induced RAW 264.7 macrophages.

RESULTS

A total of 30 potential effective exogenous components in GXB were ascertained by three-dimensional pattern recognition after conducting Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) analysis. GXB demonstrated a significant ameliorative effect on atherosclerotic symptoms in ApoE-/- mice under a high-fat diet, as evidenced by decreasing serum lipid levels, atherosclerotic plaques (aorta and aortic root) and IL-6 content. Subsequently, metabolomics results revealed that it was associated with the regulation of endogenous metabolites, including organic acids, amino acid, fatty acids and glycerophospholipid. Next, the correlation analysis was constructed with AS targets by the network of "potential effective exogenous components-AS targets-endogenous metabolites", tentatively inferring that 18 exogenous components were candidate effective components, and lipid metabolism was the major regulation pathway of GXB. Furthermore, GXB suppressed lipid accumulation in vivo/vitro through increasing expressions of PPAGγ, ABCA1, ABCG1, and SR-B1 related to cholesterol efflux. Cucurbitacin B and 5 (6)-ene-macrostemonoside B were demonstrated as the effective components with inhibitory activity on foam cell formation and lipid accumulation.

CONCLUSION

Three-dimensional pattern recognition of exogenous components correlated with endogenous metabolites was proposed and effectively utilized to demystify the effective components of GXB in AS prevention. This strategy also provided a reference for the related studies of other classical TCM formulae.

Mangiferin alleviated poststroke cognitive impairment by modulating lipid metabolism in cerebral ischemia/reperfusion rats

INTRODUCTION

Mangiferin is a Chinese herbal extract with multiple biological activities. Mangiferin can penetrate the blood‒brain barrier and has potential in the treatment of nervous system diseases. These findings suggest that mangiferin protects the neurological function in ischemic stroke rats by targeting multiple signaling pathways. However, little is known about the effect and mechanism of mangiferin in alleviating poststroke cognitive impairment.

METHODS

Cerebral ischemia/reperfusion (I/R) rats were generated via middle cerebral artery occlusion. Laser speckle imaging was used to monitor the cerebral blood flow. The I/R rats were intraperitoneally (i.p.) injected with 40 mg/kg mangiferin for 7 consecutive days. Neurological scoring, and TTC staining were performed to evaluate neurological function. Behavioral experiments, including the open field test, elevated plus maze, sucrose preference test, and novel object recognition test, were performed to evaluate cognitive function. Metabolomic data from brain tissue with multivariate statistics were analyzed by gas chromatography‒mass spectrometry and liquid chromatography‒mass spectrometry.

RESULTS

Mangiferin markedly decreased neurological scores, and reduced infarct areas. Mangiferin significantly attenuated anxiety-like and depression-like behaviors and enhanced learning and memory in I/R rats. According to the metabolomics results, 13 metabolites were identified to be potentially regulated by mangiferin, and the differentially abundant metabolites were mainly involved in lipid metabolism.

CONCLUSIONS

Mangiferin protected neurological function and relieved poststroke cognitive impairment by improving lipid metabolism abnormalities in I/R rats.

The association between circulating fatty acids and stroke in hypertensive patients

BACKGROUND

Stroke is prevalent in hypertensive population. It has been suggested that unsaturated fatty acids (USFA) have protective effect on stroke. The effect of saturated fatty acids (SFAs) on stroke is still unclear. Therefore, we studied the relationship between circulating fatty acids and acute ischemic stroke (AIS) in hypertensive patients.

METHODS

Eighty-nine pairs including 100 men and 78 women matched by sex and age were recruited. Each pair included a hypertensive patient within 48h of AIS onset and a hypertensive patient without stroke. Six circulating fatty acids were methylated before concentration determination which was repeated twice with percent recovery estimated.

RESULTS

There were differences in educational level (P = 0.002) and occupation (P < 0.001) between stroke and non-stroke participants. All the 6 fatty acid levels were higher in non-stroke participants (P = 0.017 for palmitoleic acid, 0.001 for palmitic acid, <0.001 for linoleic acid, <0.001 for behenic acid, <0.001 for nervonic acid and 0.002 for lignoceric acid). In logistic regression analysis, AIS was inversely associated with fatty acid levels except for lignoceric acid. After adjustment for education and occupation, the palmitoleic acid and palmitic acid levels were no longer inversely associated with AIS. After further adjustment for systolic blood pressure, smoking, drinking, total cholesterol and triglyceride, the inverse associations of linoleic acid (OR = 0.965, 95%CI = 0.942-0.990, P = 0.005), behenic acid (OR = 0.778, 95%CI = 0.664-0.939, P = 0.009), nervonic acid (OR = 0.323, 95%CI = 0.121-0.860, P = 0.024) with AIS remained significant.

CONCLUSIONS

Circulating fatty acids except lignoceric acid were inversely associated with AIS. Both USFAs and SFAs may have beneficial effect on stroke prevention in hypertensive population.

Widely targeted quantitative lipidomics reveal lipid remodeling in adipose tissue after long term of the combined exposure to bisphenol A and fructose

Adipose tissue is the main organ that stores lipids and it plays important roles in metabolic balance in the body. We recently reported in Human and Experimental Toxicology that the combined exposure to BPA and fructose may interfere with energy metabolism of adipose tissue. However, it is still unclear whether the combined exposure to BPA and fructose has the possibility to induce lipid remodeling in adipose tissue. In the present study, we performed a widely targeted quantitative lipidomic analysis of the adipose tissue of rats after 6 months of BPA and fructose combined exposure. We totally determined 734 lipid molecules in the adipose tissue of rats. Principal component analysis (PCA) showed the group of the combined exposure to higher-dose (25 μg/kg every other day) BPA and fructose can be distinguished from the groups of control, higher-dose BPA exposure and fructose exposure clearly. Partial least squares-discriminant analysis (PLS-DA) and univariate statistical analysis displayed lipids of PC(18:0_ 20:3), TG(8:0_14:0_16:0), TG(12:0_14:0_16:1), TG(10:0_16:0_16:1), TG(12:0_ 14:0_18:1), TG(14:0_ 16:0_16:1), TG(14:0_14:1_16:1), TG(8:0_ 16:1_16:2), TG(14:1_16:1_ 16:1), TG(16:1_18:1_18:1), TG(16:0_16:1_20:4) and TG(15:0_18:1_ 24:1) may contributed the most to the discrimination. These findings indicated that combined exposure to BPA and fructose has the potential to cause lipid remodeling in adipose tissue.

Metabolomics profiling to characterize cerebral ischemia-reperfusion injury in mice

Cerebral ischemia, resulting from compromised blood flow, is one of the leading causes of death worldwide with limited therapeutic options. Potential deleterious injuries resulting from reperfusion therapies remain a clinical challenge for physicians. This study aimed to explore the metabolomic alterations during ischemia-reperfusion injury by employing metabolomic analysis coupled with gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) and ultraperformance liquid chromatography quadrupole (UPLC/Q)-TOF-MS. Metabolomic data from mice subjected to middle cerebral artery occlusion (MCAO) followed by reperfusion (MCAO/R) were compared to those of the sham and MCAO groups. A total of 82 simultaneously differentially expressed metabolites were identified among each group. The top three major classifications of these differentially expressed metabolites were organic acids, lipids, and organooxygen compounds. Metabolomics pathway analysis was conducted to identify the underlying pathways implicated in MCAO/R. Based on impactor scores, the most significant pathways involved in the response to the reperfusion after cerebral ischemia were glycerophospholipid metabolism, linoleic acid metabolism, pyrimidine metabolism, and galactose metabolism. 17 of those 82 metabolites were greatly elevated in the MCAO/Reperfusion group, when compared to those in the sham and MCAO groups. Among those metabolites, glucose-6-phosphate 1, fructose-6-phosphate, cellobiose 2, o-phosphonothreonine 1, and salicin were the top five elevated metabolites in MCAO/R group, compared with the MCAO group. Glycolysis, the pentose phosphate pathway, starch and sucrose metabolism, and fructose and mannose degradation were the top four ranked pathways according to metabolite set enrichment analysis (MSEA). The present study not only advances our understanding of metabolomic changes among animals in the sham and cerebral ischemia groups with or without reperfusion via metabolomic profiling, but also paves the way to explore potential molecular mechanisms underlying metabolic alteration induced by cerebral ischemia-reperfusion.

Large-Scale Targeted Sequencing Study of Ischemic Stroke in the Han Chinese Population

Background Ischemic stroke is likely caused by interactions of multiple genes and environmental determinants. However, large-scale sequencing studies to discern functional genetic variants and their interactions with clinical and lifestyle risk factors on ischemic stroke are limited. Methods and Results We sequenced functional regions of 740 previously identified genes associated with atherosclerotic disease among 999 ischemic stroke cases and 1001 controls of Chinese ancestry. Multiple logistic regression models were used to examine the associations between variants and ischemic stroke and test interactions between variants and clinical and lifestyle risk factors. Functional variants achieving suggestive significance were replicated in an independent sample of 4724 ischemic stroke cases and 5029 controls. Driven by variant main effects, each minor allele of the correlated rs174535, rs174545, and rs3834458 variants at MYRF-FADS1-FADS2 conferred an average 0.83-fold (95% CI, 0.78-0.88) decreased odds of stroke. Significant main effects of MTHFR rs1801133 missense variant were also observed, with each copy of the A allele associated with a 1.20-fold (95% CI, 1.13-1.27) higher odds of ischemic stroke. The functional ALDH2 rs671 variant was identified in interaction analyses with alcohol drinking (Meta-P=3.39×10-17). Each minor allele conferred a 0.54-fold (95% CI, 0.45-0.64) decreased odds of stroke among drinkers and a 0.89-fold (95% CI, 0.83-0.97) decreased odds among nondrinkers. Conclusions Significant associations at MYRF-FADS1-FADS2 indicate that genetically elevated polyunsaturated fatty acids may decrease ischemic stroke risk in East Asians. Significant associations at MTHFR and ALDH2 robustly confirm deleterious effects of genetically elevated homocysteine and alcohol intake, respectively, on ischemic stroke.

Key Phytochemicals and Biological Functions of Chuanxiong Rhizoma Against Ischemic Stroke: A Network Pharmacology and Experimental Assessment

Presently, the treatment options for ischemic stroke (IS) are limited due to the complicated pathological process of the disease. Chuanxiong Rhizome (CR), also known as Conioselinum anthriscoides "Chuanxiong" (rhizome), is the most widely used traditional Chinese medicine for treating stroke. This study aimed to uncover the key phytochemicals and biological functions of CR against IS through a network pharmacology approach combining with IS pathophysiology analysis. We employed permanent unilateral common carotid artery ligation to construct a mouse model of global cerebral ischemia and found that cerebral ischemia injuries were improved after 7 days of gavage treatment of CR (1,300 mg/kg/day). CR exerts protective effects on neurons mainly by acting on targets related to synaptic structure, synaptic function, neuronal survival and neuronal growth. A total of 18 phytochemicals from CR based on UHPLC-MS/MS that corresponded to 85 anti-IS targets. Coniferyl ferulate, neocnidilide and ferulic acid were identified as the key phytochemicals of CR against IS. Its brain protective effects involve anti-inflammatory, anti-oxidative stress, and anti-cell death activities and improves blood circulation. Additionally, the two most important synergistic effects of CR phytochemicals in treating IS are prevention of infection and regulation of blood pressure. In brain samples of Sham mice, L-tryptophan and vanillin were detected, while L-tryptophan, gallic acid, vanillin and cryptochlorogenic acid were detected in IS mice by UHPLC-MS/MS. Our findings provide a pathophysiology relevant pharmacological basis for further researches on IS therapeutic drugs.

Serum n-6 polyunsaturated fatty acids and risk of atrial fibrillation: the Kuopio Ischaemic Heart Disease Risk Factor Study

Purpose

N-6 polyunsaturated fatty acids (PUFA), particularly linoleic acid (LA), have been associated with lower risk of coronary heart disease (CHD), but little is known about their antiarrhythmic properties. We investigated the association of the serum n-6 PUFAs with the risk of atrial fibrillation (AF), the most common type of cardiac arrhythmia.

Methods

The study included 2450 men from the Kuopio Ischaemic Heart Disease Risk Factor Study, aged 42–60 years at baseline. The total n-6 PUFA includes linoleic acid (LA), arachidonic acid (AA), γ-linolenic acid (GLA) and dihomo-γ-linolenic acid (DGLA). Cox proportional hazards regression was used to estimate hazard ratio (HR) of incident events.

Results

During the mean follow-up of 22.4 years, 486 AF cases occurred. The multivariable-adjusted HR in the highest versus the lowest quartile of total serum n-6 PUFA concentration was 0.79 (95% CI 0.58–1.08, P trend = 0.04). When evaluated individually, only serum LA concentration was inversely associated with AF risk (multivariable-adjusted extreme-quartile HR 0.69, 95% CI 0.51–0.94, P trend = 0.02). These associations were stronger among the men without history of CHD or congestive heart failure at baseline, compared to men with such disease history (P for interaction = 0.05 for total n-6 PUFA and LA). Similar associations were observed with dietary LA and AA intakes. No significant associations were observed with serum AA, GLA or DGLA concentrations.

Conclusions

Higher circulating concentration and dietary intake of n-6 PUFA, mainly LA, are associated with lower risk of AF, especially among men without history of CHD or congestive heart failure.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-021-02780-0.

Statement on additional scientific evidence in relation to the essential composition of total diet replacement for weight control

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to revise the Opinion on the essential composition of total diet replacements for weight control (TDRs) regarding the minimum content of linoleic acid (LA) and alpha-linolenic acid (ALA) and the maximum content of magnesium (Mg). Through a comprehensive literature search, human studies were retrieved reporting on LA and ALA concentrations in adipose tissue (AT), on weight loss and gallstone formation following TDR consumption and on diarrhoea after supplemental Mg intake. The distribution of the amount of LA and ALA release from AT during weight loss when consuming TDRs was estimated using statistical simulations. Using the fifth percentile, the coverage of the adequate intake (AI) for both FA was estimated. For the risk of developing diarrhoea when consuming TDRs with an Mg content of 350 mg/day, four cross-over studies using 360-368 mg Mg/day were reviewed. The Panel concludes that (1) there is no need to add LA to TDRs, as the amount released from AT during weight loss when consuming TDRs is sufficient to cover the AI for LA; (2) a minimum of 0.8 g/day ALA is needed in TDRs in order to meet the AI for ALA; (3) the minimum fat content of TDRs of 20 g/day as derived in the Panel's previous opinion is proposed to be maintained until the availability of further evidence, given the considerable uncertainty as to the amount of fat required for reducing the risk of gallstone formation; and (4) the likelihood that Mg-induced diarrhoea occurs at a severity that may be considered of concern for overweight and obese individuals consuming TDRs is low when the total maximum Mg content in TDRs is 350 mg/day.

Systemic administration of sunflower oil exerts neuroprotection in a mouse model of transient focal cerebral ischaemia

OBJECTIVES

Natural products are valuable sources of nutraceuticals for the prevention or treatment of ischemic stroke, a major cause of death and severe disability worldwide. Among the mechanisms implicated in cerebral ischemia-reperfusion damage, oxidative stress exerts a pivotal role in disease progression. Given the high antioxidant potential of most components of sunflower oil, we have explored its effects on ischemic brain injury produced in the mouse by transient occlusion of the middle cerebral artery (MCAo).

KEY FINDINGS

Intraperitoneal (i.p.) administration of sunflower oil at doses of 3 ml/kg (48 h, 24 h and 1 h before MCAo) significantly reduced brain infarct volume and oedema assessed 24 h after the insult. This neuroprotective treatment schedule also prevented the elevation of brain lipid peroxidation produced by MCAo-reperfusion injury. By contrast, doses of 0.03 ml/kg of sunflower oil resulted ineffective on both cerebral damage and lipid peroxidation. Although sunflower oil did not affect serum levels of Diacron-reactive oxygen metabolites (d-ROMs), both 0.03 and 3 ml/kg dosing regimens resulted in the preservation of serum biological antioxidant potential (BAP) that was otherwise dramatically reduced 24 h after MCAo.

CONCLUSIONS

Sunflower oil represents a promising source of neuroprotective extracts/compounds that can be exploited for the prevention and/or treatment of cerebral ischemia.

Biomarker of dietary linoleic acid and risk for stroke: A systematic review and meta-analysis

OBJECTIVE

Previous observational studiíes provided conflicting findings on the relationship between linoleic acid (LA) and the risk for stroke. The aim of this study was to evaluate the association of LA levels in blood or adipose tissue samples with risk for stroke.

METHODS

PubMed, Web of Science, and Embase databases were searched until February 29, 2020 to identify eligible observational studies, including cohort studies, nested case-control studies, case-cohort studies, and case-control studies, reporting the association of LA with the risk for stroke and its subtypes. We pooled hazard ratio (HR) estimates with 95% confidence intervals (CIs) and conducted heterogeneity test. Sensitivity analysis and publication bias test were also carried out.

RESULTS

Twelve studies from 11 observational articles involving 47 836 individuals were included in the meta-analysis. We observed an inverse association between biomarkers of dietary LA and risk for total stroke (HR, 0.88; 95% CI, 0.83-0.94; P < 0.001). Meta-regression analysis suggested that ethnicity (P = 0.029) and study design (P = 0.049) contributed to between-study heterogeneity. Subgroup analysis showed that the association was statistically significant among studies conducted in white (P < 0.001) and Asian (P = 0.032) populations, and those with cohort (P = 0.001) and case-cohort design (P = 0.007). Moreover, we found that higher LA levels were associated with a reduced risk for ischemic stroke (HR, 0.87; 95% CI, 0.80-0.95; P = 0.001), although no statistically significant association was found between LA levels and the risk for hemorrhagic stroke.

CONCLUSIONS

The present study supported an inverse association of LA levels with the risk for stroke, particularly ischemic stroke. Racial disparity exists in the association between LA and the risk for stroke, which deserves further studies.

Substitutions between potatoes and other vegetables and risk of ischemic stroke

PURPOSE

Intake of vegetables has been associated with a lower risk of ischemic stroke in observational studies controlling for total energy intake. However, adjustment for energy intake introduces a substitution aspect, which affects the interpretation of the results. We investigated replacement of potatoes with other vegetables, substitutions between vegetable subgroups, and risk of ischemic stroke and ischemic stroke subtypes.

METHODS

The Danish Diet, Cancer and Health cohort included 57,053 participants aged 50-64 years at recruitment in 1993-1997. Diet was assessed from a validated 192-item semi-quantitative food frequency questionnaire. We calculated hazard ratios (HR) with 95% confidence intervals (CI) for the incidence of ischemic stroke using Cox proportional hazard regression.

RESULTS

During 13.5 years of follow-up, 1879 cases of ischemic stroke were identified including 319 cases of large-artery atherosclerosis and 844 cases of small-vessel occlusion. The adjusted HR for total ischemic stroke associated with food substitutions of equal amounts (500 g/week) was 0.86 (95% CI 0.76, 0.97) for replacement of potatoes with fruiting vegetables and 0.92 (95% CI 0.84, 1.02) for replacement of potatoes with other root vegetables. The HR for replacing potatoes with the sum of other vegetables was 0.95 (95% CI 0.90, 1.00). Substitution of cabbage for either potatoes, fruiting vegetables or other root vegetables was associated with a statistically non-significant higher risk of ischemic stroke. The patterns of associations were similar for ischemic stroke subtypes and for equivalent substitutions using isocaloric amounts.

CONCLUSION

Replacing potatoes with fruiting vegetables was associated with a lower risk of ischemic stroke.

Plasma Phospholipid Fatty Acids, FADS1 and Risk of 15 Cardiovascular Diseases: A Mendelian Randomisation Study

Whether circulating fatty acids (FAs) play a causal role in the development of cardiovascular disease (CVD) remains unclear. We conducted a Mendelian randomisation study to explore the associations between plasma phospholipid FA levels and 15 CVDs. Summary-level data from the CARDIoGRAMplusC4D, MEGASTROKE, and Atrial Fibrillation consortia and UK Biobank were used. Sixteen single-nucleotide polymorphisms (SNPs) associated with ten plasma FAs were used as instrumental variables. SNPs in or close to the FADS1 gene were associated with most FAs. We performed a secondary analysis of the association between a functional variant (rs174547) in FADS1, which encodes ?5-desaturase (a key enzyme in the endogenous FA synthesis), and CVD. Genetic predisposition to higher plasma α-linolenic, linoleic, and oleic acid levels was associated with lower odds of large-artery stroke and venous thromboembolism, whereas higher arachidonic and stearic acid levels were associated with higher odds of these two CVDs. The associations were driven by SNPs in or close to FADS1. In the secondary analysis, the minor allele of rs174547 in FADS1 was associated with significantly lower odds of any ischemic stroke, large-artery stroke, and venous thromboembolism and showed suggestive evidence of inverse association with coronary artery disease, abdominal aortic aneurysm and aortic valve stenosis. Genetically higher plasma α-linolenic, linoleic, and oleic acid levels are inversely associated with large-artery stroke and venous thromboembolism, whereas arachidonic and stearic acid levels are positively associated with these CVDs. The associations were driven by FADS1, which was also associated with other CVDs.

Polyunsaturated Fatty Acids and Risk of Ischemic Stroke

Ischemic stroke is a major cause of death and morbidity worldwide. It has been suggested that polyunsaturated fatty acids (PUFAs) may be associated with a lower risk ischemic stroke, but this has been far less studied than their role for coronary heart disease. In this paper, we summarize the main findings from previous follow-up studies investigating associations between intake or biomarkers of the major PUFAs including alpha-linolenic acid (ALA), marine n-3 PUFAs and linoleic acid (LA) and the development of ischemic stroke. Several follow-up studies have suggested that marine n-3 PUFAs may be associated with a lower risk of ischemic stroke although results have not been consistent and limited knowledge exist on the individual marine n-3 PUFAs and ischemic stroke and its subtypes. The role of ALA is less clear, but most studies have not supported that ALA is appreciably associated with ischemic stroke risk. Some studies have supported that LA might be associated with a lower risk of total ischemic stroke, while limited evidence exist on PUFAs and ischemic stroke subtypes. The associations may depend on the macronutrients that PUFAs replace and this substitution aspect together with focus on dietary patterns represent interesting areas for future research.

Marine n-3 Polyunsaturated Fatty Acids and the Risk of Ischemic Stroke

Background and Purpose—

We hypothesized that total marine n-3 polyunsaturated fatty acids (PUFA), in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the diet and in adipose tissue (biomarkers of long-term intake and endogenous exposure) were inversely associated with the risk of ischemic stroke and its subtypes.

Methods—

The Diet, Cancer and Health cohort consisted of 57 053 participants aged 50 to 65 years at enrolment. All participants filled in a food frequency questionnaire and had an adipose tissue biopsy taken at baseline. Information on ischemic stroke during follow-up was obtained from The Danish National Patient Register, and all cases were validated. Cases and a random sample of 3203 subjects from the whole cohort had their fatty acid composition of adipose tissue determined by gas chromatography.

Results—

During 13.5 years of follow-up 1879 participants developed an ischemic stroke. Adipose tissue content of EPA was inversely associated with total ischemic stroke (hazard ratio [HR], 0.74; 95% CI, 0.62–0.88) when comparing the highest with the lowest quartile. Also, lower rates of large artery atherosclerosis were seen with higher intakes of total marine n-3 PUFA (HR, 0.69; 95% CI, 0.50–0.95), EPA (HR, 0.66; 95% CI, 0.48–0.91) and DHA (HR, 0.72; 95% CI, 0.53–0.99), and higher adipose tissue content of EPA (HR, 0.52; 95% CI, 0.36–0.76). Higher rates of cardioembolism were seen with higher intakes of total marine n-3 PUFA (HR, 2.50; 95% CI, 1.38–4.53) and DHA (HR, 2.12; 95% CI, 1.21–3.69) as well as with higher adipose tissue content of total marine n-3 PUFA (HR, 2.63; 95% CI, 1.33–5.19) and DHA (HR, 2.00; 95% CI, 1.04–3.84). The EPA content in adipose tissue was inversely associated with small-vessel occlusion (HR, 0.69; 95% CI, 0.55–0.88).

Conclusions—

EPA was associated with lower risks of most types of ischemic stroke, apart from cardioembolism, while inconsistent findings were observed for total marine n-3 PUFA and DHA.

Substitution of Fish for Red Meat or Poultry and Risk of Ischemic Stroke

We investigated the risk of ischemic stroke and its subtypes when red meat or poultry was substituted with fish. A total of 57,053 participants aged 50⁻65 years at baseline were included in the Danish Diet, Cancer and Health study. All participants filled in a food-frequency questionnaire at recruitment. Potential ischemic stroke cases were identified by linkage to the Danish National Patient Register, and all cases were validated and subclassified. Substitutions were investigated as 150 g/week of fish for 150 g/week of red meat or of poultry using multivariable Cox proportional hazard regression models. During 13.5 years of follow-up, 1879 participants developed an ischemic stroke. Replacing red meat or poultry with fish was not associated with the rate of total ischemic stroke, but there was a statistically significant lower rate of large artery atherosclerosis when fish replaced processed (hazard ratio (HR): 0.78; 95% confidence interval (CI): 0.67; 0.90) and unprocessed (HR: 0.87; 95% CI: 0.75; 0.99) red meat. A statistically significant higher rate of cardioembolism was found when poultry was replaced by total fish (HR: 1.42; 95% CI: 1.04; 1.93). When fatty fish replaced unprocessed red meat, a statistically significant lower rate of small-vessel occlusion was found (HR: 0.88; 95% CI: 0.77; 0.99). In conclusion, replacing red meat with fish was not associated with risk of total ischemic stroke but was associated with a lower risk of subtypes of ischemic stroke.