Association between fish consumption and all-cause and cause-specific mortality in Japan: NIPPON DATA80, 1980-99

Dietary Factors, Dietary Patterns, and Cardiovascular Disease Risk in Representative Japanese Cohorts: NIPPON DATA80/90

Diet is one of the most important factors affecting healthy life expectancy through the onset of cardiovascular disease (CVD) risk as well as various chronic diseases. Because dietary habits and disease structure differ depending on the country, region, and/or race, evidence from each population is required. NIPPON DATA80/90 is a long-term cohort study of a representative Japanese population that participated in national nutrition surveys. Among the many findings of this cohort study, a dietary pattern with higher intake of fruits, vegetables, fish (n-3 polyunsaturated fatty acids), and dietary fiber and lower intake of salt as well as sodium-to-potassium ratio was found to be associated with a lower risk of CVD mortality. The results from our cohort study would be useful for effectively preventing CVD. This article reviews the published studies from the NIPPON DATA80/90 to highlight the significant findings that may be used to develop risk prevention strategies for CVD.

Japanese-Style Diet and Cardiovascular Disease Mortality: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

This systematic review and meta-analysis elucidate the effects of the Japanese-style diet and characteristic Japanese foods on the mortality risk of cardiovascular disease (CVD), cerebrovascular disease (stroke), and heart disease (HD). This review article followed the PRISMA guidelines. A systematic search in PubMed, The Cochrane Library, JDreamIII, and ICHUSHI Web identified prospective cohort studies on Japanese people published till July 2020. The meta-analysis used a random-effects model, and heterogeneity and publication bias were evaluated with I² statistic and Egger’s test, respectively. Based on inclusion criteria, we extracted 58 articles, including 9 on the Japanese-style diet (n = 469,190) and 49 (n = 2,668,238) on characteristic Japanese foods. With higher adherence to the Japanese-style diet, the pooled risk ratios (RRs) for CVD, stroke, heart disease/ischemic heart disease combined (HD/IHD) mortality were 0.83 (95% CI, 0.77–0.89, I² = 58%, Egger’s test: p = 0.625, n = 9 studies), 0.80 (95% CI, 0.69–0.93, I² = 66%, Egger’s test: p = 0.602, n = 6 studies), and 0.81 (95% CI, 0.75–0.88, I² = 0%, Egger’s test: p = 0.544, n = 6 studies), respectively. Increased consumption of vegetables, fruits, fish, green tea, and milk and dairy products decreased the RR for CVD, stroke, or HD mortality. Increased salt consumption elevated the RR for CVD and stroke mortality. Increased consumption of dietary fiber and plant-derived protein decreased the RR for CVD, stroke, and HD/IHD mortality. The Japanese-style diet and characteristic Japanese foods may reduce CVD mortality. Most studies conducted diet surveys between 1980 and the 1990s. This meta-analysis used articles that evaluated the same cohort study by a different method. A new large-scale cohort study matching the current Japanese dietary habits is needed to confirm these findings.

Differential Association of Serum n-3 Polyunsaturated Fatty Acids with Various Cerebrovascular Lesions in Japanese Men

BACKGROUND

An association between a high intake of marine-derived n-3 polyunsaturated fatty acids (n-3 PUFAs) with a lower risk of coronary heart disease was previously reported. However, the association between n-3 PUFAs and cerebrovascular lesions remains unclear. We evaluated this association in a general-population-based sample of Japanese men.

METHODS

Participants were community-dwelling men (40-79 years old) living in Kusatsu City, Shiga, Japan. Serum concentrations of n-3 PUFAs, defined as the sum of eicosapentaenoic and docosahexaenoic acids, were measured via gas-liquid chromatography between 2006 and 2008. Magnetic resonance imaging was used to assess cerebrovascular lesions (including intracerebral large-artery stenosis, lacunar infarction, and microbleeds) and white matter lesions between 2012 and 2015. Logistic regression adjusting for conventional cardiovascular risk factors was used to estimate the odds ratio of prevalent cerebrovascular lesions per 1 standard deviation higher serum concentration of n-3 PUFAs.

RESULTS

Of a total of 739 men, the numbers (crude prevalence in %) of prevalent cerebral large-artery stenoses, lacunar infarctions, microbleeds, and white matter lesions were 222 (30.0), 162 (21.9), 103 (13.9), and 164 (22.2), respectively. A 1 standard deviation higher concentration of n-3 PUFAs (30.5 μmol/L) was independently associated with lower odds of cerebral large-artery stenosis (multivariable-adjusted odds ratio, 0.80; 95% confidential interval, 0.67-0.97). There were no significant associations of n-3 PUFAs with the other types of lesions.

CONCLUSIONS

n-3 PUFAs may have protective effects against large-artery stenosis, but not small vessel lesions, in the brain.

Impact of fish consumption on all-cause mortality in older people with and without dementia: a community-based cohort study

BACKGROUND

Increased fish consumption reduces the risk of dementia. However, it is unknown whether fish consumption reduced all-cause mortality in people with dementia. The purpose of the study is to investigate the association of fish consumption with all-cause mortality in older people with dementia versus those without dementia.

METHODS

Using a standard method of the Geriatric Mental State, we interviewed 4165 participants aged ≥ 60 years who were randomly recruited from five provinces in China during 2007-2009 to collect the baseline data of socio-demography, disease risk factors, histories of disease, and details of dietary intakes, and diagnosed dementia (n = 406). They were followed up for vital status until 2012.

RESULTS

The cohort follow-up documented 329 deaths; 61 were in participants with dementia (55.3 per 1000 person-years) and 224 were those without dementia (22.3). In all participants, the risk of all-cause mortality was reduced with fish intake at " ≥ twice a week" (multivariate-adjusted hazard ratio 0.58, 95% CI 0.34-0.96) and at "once a week or less" (0.79, 0.53-1.18) compared to "never eat" over the past two years. In participants without baseline dementia, the corresponding HRs for all-cause mortality were 0.57 (0.33-0.98) and 0.85 (0.55-1.31), while in participants with dementia were 1.36 (0.28-6.60) and 1.05 (0.30-3.66), respectively.

CONCLUSION

This study reveals that consumption of fish in older age reduced all-cause mortality in older people without dementia, but not in people with dementia. Fish intake should be increased in older people in general, prior to the development of dementia in the hope of preventing dementia and prolonging life.

Dietary Omega-3 Fatty Acid Intake and Mortality in CKD Population: A 1999-2014 NHANES Analysis

INTRODUCTION

High risk of early death, especially contributed to cardiovascular disease, exists in patients who have chronic kidney disease (CKD). And the burden of cardiovascular disease is able to be lightened by an increase in omega-3 polyunsaturated fatty acid (omega-3 PUFA). A diet high in omega-3 PUFA in the general population is protective, although it is inconclusive about its beneficial role in the CKD population.

METHODS

From the 1999 to 2014 National Health and Nutrition Examination Surveys (NHANES), we can collect 2,990 participants who suffered from CKD, who were classified into 4 groups: <0.86, 0.87-1.30, 1.31-1.92, and 1.93-9.65 g/day based on NHANES 24-h dietary recall questionnaire dietary omega-3 PUFA. Moreover, their mortality details were available to be obtained by linking NHANES to the National Death Index. The associations between dietary omega-3 PUFA and mortality were evaluated by constructing multivariable Cox proportional hazards models.

RESULTS

Over 8 years of a median follow-up, 864 deaths were recorded. The adjusted hazard ratios (95% confidence interval) for all-cause mortality of the diseased people with CKD in the 2nd (0.87-1.30 g/day), 3rd (0.87-1.30 g/day), and 4th (1.93-9.65 g/day) quartiles of dietary omega-3 PUFA were 0.94 (0.72, 1.23), 0.74 (0.54, 1.02), and 0.67 (0.48, 0.93), respectively, versus those with the lowest quartile of dietary omega-3 PUFA intake (<0.86 g/day) (p for trend = 0.011).

CONCLUSION

There may be a inverse relation of dietary omega-3 PUFA intake and all-cause mortality in patients with CKD. Therefore, an increase of dietary omega-3 PUFA may be encouraged to be used clinically in patients with CKD.

Role of polyunsaturated fatty acids in ischemic stroke - A perspective of specialized pro-resolving mediators

Polyunsaturated fatty acids (PUFAs) have been proposed as beneficial for cardiovascular health. However, results from both epidemiological studies and clinical trials have been inconsistent, whereas most of the animal studies showed promising benefits of PUFAs in the prevention and treatment of ischemic stroke. In recent years, it has become clear that PUFAs are metabolized into various types of bioactive derivatives, including the specialized pro-resolving mediators (SPMs). SPMs exert multiple biofunctions, such as to limit excessive inflammatory responses, regulate lipid metabolism and immune cell functions, decrease production of pro-inflammatory factors, increase anti-inflammatory mediators, as well as to promote tissue repair and homeostasis. Inflammation has been recognised as a key contributor to the pathophysiology of acute ischemic stroke. Owing to their potent pro-resolving actions, SPMs are potential for development of novel anti-stroke therapy. In this review, we will summarize current knowledge of epidemiological studies, basic research and clinical trials concerning PUFAs in stroke prevention and treatment, with special attention to SPMs as the unsung heroes behind PUFAs.

Intake of fish and long-chain n-3 polyunsaturated fatty acids and risk of diseases in a Japanese population: a narrative review

Since the 1970s, the potential benefit of fish intake in terms of noncommunicable diseases has been one of the most important themes in disease prevention. Epidemiological studies have revealed the extent to which fish consumption affects the incidence of and mortality from diseases. Meta-analyses summarized the effect of fish and long-chain n-3 polyunsaturated fatty acid intake on noncommunicable diseases, especially cardiovascular diseases in Western countries. However, few reviews have spotlighted the effect of fish intake in East-Asian countries that have high population levels of fish intake such as Japan. We narratively reviewed the epidemiological studies concerned with the associations of fish and long-chain n-3 polyunsaturated fatty acid intake with risk of noncommunicable diseases, mainly of cardiovascular disease, among Japanese, whose fish intake has been twice or more than that of most Westerners. Overall, fish or long-chain n-3 polyunsaturated fatty acid intake may be beneficial for prevention of noncommunicable diseases, especially coronary heart disease and heart failure in Japanese as well as in Westerners. However, the beneficial effects of their intakes seemed to be nonlinear and varied according to disease severity and culture. Studies on other noncommunicable disease were also narratively reviewed.

A genome-wide association study on fish consumption in a Japanese population-the Japan Multi-Institutional Collaborative Cohort study

BACKGROUND/OBJECTIVE

Although benefits of fish consumption for health are well known, a significant percentage of individuals dislike eating fish. Fish consumption may be influenced by genetic factors in addition to environmental factors. We conducted a genome-wide association study (GWAS) to find genetic variations that affect fish consumption in a Japanese population.

METHODS

We performed a two-stage GWAS on fish consumption using 13,739 discovery samples from the Japan Multi-Institutional Collaborative Cohort study, and 2845 replication samples from the other population. We used a semi-quantitative food frequency questionnaire to estimate food intake. Association of the imputed variants with fish consumption was analyzed by separate linear regression models per variant, with adjustments for age, sex, energy intake, principal component analysis components 1-10, and alcohol intake (g/day). We also performed conditional analysis.

RESULTS

We found 27 single nucleotide polymorphisms (SNPs) located in 12q24 and 14q32.12 that were associated with fish consumption. The 19 SNPs were located at 11 genes including six lead SNPs at the BRAP, ACAD10, ALDH2, NAA25, and HECTD4 regions on 12q24.12-13, and CCDC197 region on 14q32.12. In replication samples, all five SNPs located on chromosome 12 were replicated successfully, but the one on chromosome 14 was not. Conditional analyses revealed that the five lead variants in chromosome 12 were in fact the same signal.

CONCLUSION

We found that new SNPs in the 12q24 locus were related to fish intake in two Japanese populations. The associations between SNPs on chromosome 12 and fish intake were strongly confounded by drinking status.

Fish Consumption and Coronary Heart Disease: A Meta-Analysis

Epidemiological studies on the impact of fish consumption on coronary heart disease (CHD) incidence have shown inconsistent results. In addition, in terms of CHD mortality, although previous meta-analyses showed that fish consumption reduces the risk of CHD, six newly incorporated studies show that fish consumption has no impact on CHD. Therefore, the results still need to be verified. The purpose of this study is to quantitatively evaluate the impact of fish consumption on CHD incidence and mortality. Relevant studies were identified from PubMed, Web of Science, and Embase databases up to October 2019. The multivariate-adjusted relative risks (RRs) for the highest versus the lowest fish consumption categories and the 95% confidence intervals were computed with a random-effect model. A restricted cubic spline regression model was used to assess the dose–response relationship between fish consumption and CHD incidence and mortality. Forty prospective cohort studies were incorporated into research. Among them, 22 studies investigated the association between fish consumption and CHD incidence (28,261 cases and 918,783 participants), and the summary estimate showed that higher fish consumption was significantly associated with a lower CHD incidence [RR: 0.91, 95% CI: (0.84, 0.97); I² = 47.4%]. Twenty-seven studies investigated the association between fish consumption and CHD mortality (10,568 events and 1,139,553 participants), and the summary estimate showed that higher fish intake was significantly associated with a lower CHD mortality [RR: 0.85, 95% CI: (0.77, 0.94); I² = 51.3%]. The dose–response analysis showed that the CHD incidence and mortality were reduced by 4%, respectively, with a 20 g/day increment in fish consumption. This meta-analysis indicates that fish consumption is associated with a lower CHD incidence and mortality.

Is There Something Fishy About Fish Oil?

BACKGROUND

Fish is consumed as food worldwide and is considered as a rich source of essential nutrients required for a healthy life. Supplementation with fish oil has been adopted as a solution to prevent or cure many pathophysiological states and diseases by both the professionals and the civil population. The beneficial effects are, however, being questioned, as some controversial results were obtained in clinical and population studies.

METHODS

Critical evaluation of studies regarding known effects of fish oil, both in favour of its consumption and related controversies.

RESULTS

From the literature review, contradictory allegations about the positive action of the fish oil on human health emerged, so that a clear line about its beneficial effect cannot be withdrawn.

CONCLUSION

Scientific results on the application of fish oil should be taken with caution as there is still no standardised approach in testing its effects and there are significantly different baselines in respect to nutritional and other lifestyle habits of different populations.

Omega-3 Polyunsaturated Fatty Acids and Stroke Burden

Stroke is a major leading cause of death and disability worldwide. N-3 polyunsaturated fatty acids (PUFAs) including eicosapentaenoic acid and docosahexaenoic acid have potent anti-inflammatory effects, reduce platelet aggregation, and regress atherosclerotic plaques. Since the discovery that the Greenland Eskimo population, whose diet is high in marine n-3 PUFAs, have a lower incidence of coronary heart disease than Western populations, numerous epidemiological studies to explore the associations of dietary intakes of fish and n-3 PUFAs with cardiovascular diseases, and large-scale clinical trials to identify the benefits of treatment with n-3 PUFAs have been conducted. In most of these studies the incidence and mortality of stroke were also evaluated mainly as secondary endpoints. Thus, a systematic literature review regarding the association of dietary intake of n-3 PUFAs with stroke in the epidemiological studies and the treatment effects of n-3 PUFAs in the clinical trials was conducted. Moreover, recent experimental studies were also reviewed to explore the molecular mechanisms of the neuroprotective effects of n-3 PUFAs after stroke.

Omega-3 Polyunsaturated Fatty Acids and Their Health Benefits

Omega-3 polyunsaturated fatty acids (PUFAs) include α-linolenic acid (ALA; 18:3 ω-3), stearidonic acid (SDA; 18:4 ω-3), eicosapentaenoic acid (EPA; 20:5 ω-3), docosapentaenoic acid (DPA; 22:5 ω-3), and docosahexaenoic acid (DHA; 22:6 ω-3). In the past few decades, many epidemiological studies have been conducted on the myriad health benefits of omega-3 PUFAs. In this review, we summarized the structural features, properties, dietary sources, metabolism, and bioavailability of omega-3 PUFAs and their effects on cardiovascular disease, diabetes, cancer, Alzheimer's disease, dementia, depression, visual and neurological development, and maternal and child health. Even though many health benefits of omega-3 PUFAs have been reported in the literature, there are also some controversies about their efficacy and certain benefits to human health.

Fish and Meat Intake, Serum Eicosapentaenoic Acid and Docosahexaenoic Acid Levels, and Mortality in Community-Dwelling Japanese Older Persons

The associations between meat/fish consumption, docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) intakes, and blood DHA/EPA levels, and mortality in Japan were examined as part of the National Institute for Longevity Sciences-Longitudinal Study of Aging: 520 men and 534 women (60–79 years at baseline) were followed from 1997–2017. Nutritional intakes were assessed using a 3-day dietary record and fasting venous blood samples were collected. Serum EPA/DHA concentrations, the EPA/arachidonic acid (ARA) ratio, EPA/DHA intakes, and fish/meat intakes were examined in tertiles as indicator variables, and hazard ratios (HR) were calculated to compare the risk of death across tertiles controlling for sex, age, body mass index, smoking status, alcohol drinking, physical activity, education, employment, and history of diseases. During follow-up (mean 11.7 years), 422 subjects (40.4%) died. The multivariate-adjusted HR for all-cause mortality in subjects in the highest tertile of serum DHA and EPA/ARA ratio was 0.73 (95% confidence intervals (CI): 0.53–0.99) and 0.71 (95% CI: 0.53–0.96) compared with subjects in the lowest tertile, respectively (trend p < 0.05). There were no significant associations between mortality and serum EPA/ARA and DHA/EPA intakes. An increased serum DHA level or EPA/ARA ratio might be recommended for longevity to Japanese community dwellers.

Cardiovascular Risk Assessment Chart by Dietary Factors in Japan - NIPPON DATA80

BACKGROUND

Many studies show that dietary factors such as vegetables, fruit, and salt are associated with cardiovascular disease (CVD) risk. However, a risk assessment chart for CVD mortality according to combinations of dietary factors has not been established.Methods and Results:Participants were 9,115 men and women aged 30-79 years enrolled in the National Nutritional Survey of Japan in 1980 with a 29-year follow-up. Dietary intake was assessed using a 3-day weighed dietary record at baseline. Cox regression models were used to estimate the hazard ratio (HR) of CVD mortality stratified by vegetables, fruit, fish, and salt consumption. HRs of CVD mortality according to combinations of dietary factors were color coded on an assessment chart. Higher intakes of vegetables, fruit, and fish, and lower salt intake were associated with lower CVD mortality risk. HRs calculated from combinations of dietary factors were displayed using 5 colors corresponding to the magnitude of the HR. People with the lowest intake of vegetables, fruit, and fish, and higher salt intake had a HR of 2.87 compared with those with the highest intake of vegetables, fruit, and fish, and lower salt intake.

CONCLUSIONS

Vegetables, fruit, fish, and salt intake were independently associated with CVD mortality risk. The assessment chart generated could be used in Japan as an educational tool for CVD prevention.

Plasma levels of n-3 fatty acids and risk of coronary heart disease among Japanese: The Japan Public Health Center-based (JPHC) study

BACKGROUND AND AIMS

Higher intake of fish or n-3 polyunsaturated fatty acids (PUFAs) has been associated with reduced risk of coronary heart disease (CHD). However, it is unclear whether increased blood levels of n-3 PUFAs are associated with reduced risk of CHD in the Japanese population.

METHODS

The relationship between circulating levels of n-3 PUFAs (eicosapentaenoic acid + docosapentaenoic acid + docosahexaenoic acid) and risk of CHD was examined in a nested case-control study among participants in the Japan Public Health Center (JPHC)-based Study Cohort. Plasma n-3 PUFA phospholipid levels were measured at baseline by gas chromatography in 209 cases with CHD and 418 controls matched for sex, age, date of blood draw, time elapsed since last meal before blood collection, and study location. The CHD cases (n = 209) comprised 168 cases of myocardial infarction and 41 of sudden cardiac death, otherwise classified as 157 non-fatal and 52 fatal coronary events, respectively. Mean duration of follow-up was 13.5 years.

RESULTS

Multivariate conditional logistic analysis showed no significant association between n-3 PUFAs and risk of total CHD. The odds ratio (OR) for the highest versus lowest quartiles of plasma n-3 PUFAs was 0.79 (95% confidence interval [95% CI]: 0.41-1.51, p for trend = 0.51). Subtype analysis of CHD revealed that the multivariate ORs for the highest versus lowest quartiles for n-3 PUFAs were 0.91 (95% CI: 0.43-1.89, p for trend = 0.90) for myocardial infarction, 0.08 (95% CI: 0.01-0.88, p for trend = 0.04) for sudden cardiac death, 0.89 (95% CI: 0.42-1.89, p for trend = 0.97) for nonfatal coronary events, and 0.12 (95% CI: 0.02-0.75, p for trend = 0.03) for fatal coronary events.

CONCLUSIONS

Plasma n-3 PUFA levels were not associated with risk of total CHD but were inversely associated with risks of sudden cardiac death and fatal coronary events among middle-aged Japanese individuals.

Food groups and risk of all-cause mortality: a systematic review and meta-analysis of prospective studies

Background: Suboptimal diet is one of the most important factors in preventing early death and disability worldwide.Objective: The aim of this meta-analysis was to synthesize the knowledge about the relation between intake of 12 major food groups, including whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat, and sugar-sweetened beverages, with risk of all-cause mortality.Design: We conducted a systematic search in PubMed, Embase, and Google Scholar for prospective studies investigating the association between these 12 food groups and risk of all-cause mortality. Summary RRs and 95% CIs were estimated with the use of a random effects model for high-intake compared with low-intake categories, as well as for linear and nonlinear relations. Moreover, the risk reduction potential of foods was calculated by multiplying the RR by optimal intake values (serving category with the strongest association) for risk-reducing foods or risk-increasing foods, respectively.Results: With increasing intake (for each daily serving) of whole grains (RR: 0.92; 95% CI: 0.89, 0.95), vegetables (RR: 0.96; 95% CI: 0.95, 0.98), fruits (RR: 0.94; 95% CI: 0.92, 0.97), nuts (RR: 0.76; 95% CI: 0.69, 0.84), and fish (RR: 0.93; 95% CI: 0.88, 0.98), the risk of all-cause mortality decreased; higher intake of red meat (RR: 1.10; 95% CI: 1.04, 1.18) and processed meat (RR: 1.23; 95% CI: 1.12, 1.36) was associated with an increased risk of all-cause mortality in a linear dose-response meta-analysis. A clear indication of nonlinearity was seen for the relations between vegetables, fruits, nuts, and dairy and all-cause mortality. Optimal consumption of risk-decreasing foods results in a 56% reduction of all-cause mortality, whereas consumption of risk-increasing foods is associated with a 2-fold increased risk of all-cause mortality.Conclusion: Selecting specific optimal intakes of the investigated food groups can lead to a considerable change in the risk of premature death.

Fish Consumption, Omega-3 Fatty Acids, and Risk of Cardiovascular Disease

INTRODUCTION

Data on omega-3 polyunsaturated fatty acids in relation to cardiovascular disease are limited in women. The aim of this study was to examine longitudinal relations of tuna and dark fish, α-linolenic acid, and marine omega-3 fatty acid intake with incident major cardiovascular disease in women.

METHODS

This was a prospective cohort study of U.S. women participating in the Women's Health Study from 1993 to 2014, during which the data were collected and analyzed. A total of 39,876 women who were aged ≥45 years and free of cardiovascular disease at baseline provided dietary data on food frequency questionnaires. Analyses used Cox proportional hazards models to evaluate the association between fish and energy-adjusted omega-3 polyunsaturated fatty acid intake and the risk of major cardiovascular disease, defined as a composite outcome of myocardial infarction, stroke, and cardiovascular death, in 38,392 women in the final analytic sample (96%).

RESULTS

During 713,559 person years of follow-up, 1,941 cases of incident major cardiovascular disease were confirmed. Tuna and dark fish intake was not associated with the risk of incident major cardiovascular disease (p-trend >0.05). Neither α-linolenic acid nor marine omega-3 fatty acid intake was associated with major cardiovascular disease or with individual cardiovascular outcomes (all p-trend >0.05). There was no effect modification by age, BMI, or baseline history of hypertension.

CONCLUSIONS

In this cohort of women without history of cardiovascular disease, intakes of tuna and dark fish, α-linolenic acid, and marine omega-3 fatty acids were not associated with risk of major cardiovascular disease.

Food Consumption and its Impact on Cardiovascular Disease: Importance of Solutions Focused on the Globalized Food System: A Report From the Workshop Convened by the World Heart Federation

Major scholars in the field, on the basis of a 3-day consensus, created an in-depth review of current knowledge on the role of diet in cardiovascular disease (CVD), the changing global food system and global dietary patterns, and potential policy solutions. Evidence from different countries and age/race/ethnicity/socioeconomic groups suggesting the health effects studies of foods, macronutrients, and dietary patterns on CVD appear to be far more consistent though regional knowledge gaps is highlighted. Large gaps in knowledge about the association of macronutrients to CVD in low- and middle-income countries particularly linked with dietary patterns are reviewed. Our understanding of foods and macronutrients in relationship to CVD is broadly clear; however, major gaps exist both in dietary pattern research and ways to change diets and food systems. On the basis of the current evidence, the traditional Mediterranean-type diet, including plant foods and emphasis on plant protein sources provides a well-tested healthy dietary pattern to reduce CVD.

Fish, omega-3 long-chain fatty acids, and all-cause mortality in a low-income US population: Results from the Southern Community Cohort Study

BACKGROUND

We examined associations between fish and n-3 LCFA and mortality in a prospective study with a large proportion of blacks with low socio-economic status.

METHODS AND RESULTS

We observed 6914 deaths among 77,604 participants with dietary data (follow-up time 5.5 years). Of these, 77,100 participants had available time-to-event data. We investigated associations between mortality with fish and n-3 LCFA intake, adjusting for age, race, sex, kcal/day, body mass index (BMI), smoking, alcohol consumption, physical activity, income, education, chronic disease, insurance coverage, and meat intake. Intakes of fried fish, baked/grilled fish and total fish, but not tuna, were associated with lower mortality among all participants. Analysis of trends in overall mortality by quintiles of intake showed that intakes of fried fish, baked/grilled fish and total fish, but not tuna, were associated with lower risk of total mortality among all participants. When participants with chronic disease were excluded, the observed association remained only between intakes of baked/grilled fish, while fried fish was associated with lower risk of mortality in participants with prevalent chronic disease. The association between n-3 LCFA intake and lower risk of mortality was significant among those with diabetes at baseline. There was an inverse association of mortality with fried fish intake in men, but not women. Total fish and baked/grilled fish intakes were associated with lower mortality among blacks while fried fish intake was associated with lower mortality among whites. Effect modifications were not statistically significant.

CONCLUSION

Our findings suggest a modest benefit of fish consumption on mortality.

Association between serum long-chain n-3 and n-6 polyunsaturated fatty acid profiles and glomerular filtration rate assessed by serum creatinine and cystatin C levels in Japanese community-dwellers

Background

Plasma concentration of n-3 polyunsaturated fatty acids (PUFAs) has been reported to be associated with renal function in Western populations. However, few studies have investigated the association between serum long-chain n-3 and n-6 PUFA profiles and renal function in a Japanese population with high marine-derived long-chain n-3 PUFA intake.

Methods

A cross-sectional study was performed in 549 Japanese rural community-dwellers aged 40 to 64 years. In adjusted analysis of covariance, we assessed the relationship between estimated glomerular filtration rate (eGFR) and tertiles of serum long-chain n-3 and n-6 PUFA profiles ([eicosapentaenoic acid {EPA} + docosahexaenoic acid {DHA}]:arachidonic acid [AA]). GFR was estimated by Japanese specific equations using serum creatinine and cystatin C (eGFR_cre and eGFR_cys). Using multivariate-adjusted linear regression models, we also assessed the relationships between eGFRs and several n-3 and n-6 PUFAs, which have been suggested to be associated with renal function.

Results

In all participants, higher dietary fish intake as assessed by a semi-quantitative questionnaire was associated with higher serum value of (EPA+DHA):AA. Participants in the higher (EPA+DHA):AA tertiles had non-significantly higher eGFR_cre and significantly higher eGFR_cys (P = 0.016). In addition, eGFR_cys in T₂+T₃ of (EPA+DHA):AA was significantly higher than that in T₁ (adjusted mean eGFR_cys, T₁: 87 ml/min/1.73 m², T₂+T₃: 91 ml/min/1.73 m²; P < 0.01). Among the PUFAs, only (EPA+DHA) was significantly associated with eGFR_cys.

Conclusions

Serum (EPA+DHA):AA, which reflects an individual’s fish intake, might be associated with eGFR_cys in Japanese community-dwellers.

Risk of hypercholesterolemia for cardiovascular disease and the population attributable fraction in a 24-year Japanese cohort study

AIMS

The population-attributable fraction (PAF) is an indicator of the disease burden. In Western countries, the PAF of hypercholesterolemia in cardiovascular disease (CVD) is the highest among that for traditional risk factors; however, data for Asian populations are limited.

METHODS

A 24-year cohort study was conducted among 9,209 randomly selected participants who were not taking statins. We estimated the hazard ratio (HR) after adjusting for covariates and PAF associated with the serum total cholesterol (TC) levels in relation to CVD mortality.

RESULTS

The TC level was found to be positively associated with an increased risk of CVD, coronary heart disease (CHD) and cardiac death (CHD plus heart failure), with an HR of 1.08 (95% confidence interval [CI]: 1.00-1.16), 1.33 (95% CI: 1.14-1.55) and 1.21 (95% CI: 1.08-1.35) for a 1-SD increment in the serum TC level, respectively. Similar positive associations between the TC level and both CHD and cardiac death were observed after classifying the patients by age and sex. Furthermore, the highest serum TC level (≥ 6.72 mmol/L) was positively associated with CVD death, with an HR of 1.76 (95% CI: 1.25-2.47), as well as both CHD death and cardiac death. In contrast, no significant relationships were observed between the serum TC level and stroke. Meanwhile, the PAF for CVD, CHD, and cardiac deaths due to hypercholesterolemia (serum TC level ≥ 5.69 mmol/L, defined by the Japan Atherosclerosis Society) was 1.7%, 10.6% and 5.6%, respectively.

CONCLUSIONS

The estimated PAF of CVD death due to hypercholesterolemia is moderately high, but lower than that for other risk factors, such as hypertension.

Modification of the excess risk of coronary heart disease due to smoking by seafood/fish intake

Seafood/fish intake has been regarded as a protective factor for coronary heart disease (CHD), while smoking is a strong risk factor. To examine whether associations between smoking and risk of CHD are modified by seafood/fish intake, we studied 72,012 Japanese men and women aged 45-74 years who completed 2 food frequency questionnaires, 5 years apart, during the period 1995-2009. After 878,163 person-years of follow-up, 584 incident cases of CHD (101 fatal and 483 nonfatal), including 516 myocardial infarctions, were documented. There was a clear dose-response association between smoking and CHD risk among subjects with a low seafood/fish intake (<86 g/day) but not among those with a high seafood/fish intake (≥86 g/day). Compared with never smokers, the multivariable hazard ratios in light (1-19 cigarettes/day), moderate (20-29 cigarettes/day), and heavy (≥30 cigarettes/day) smokers were 2.39 (95% confidence interval (CI): 1.60, 3.56), 2.74 (95% CI: 1.90, 3.95), and 3.24 (95% CI: 2.12, 4.95), respectively, among low seafood/fish eaters and 1.13 (95% CI: 0.64, 1.99), 1.29 (95% CI: 0.95, 2.04), and 2.00 (95% CI: 1.18, 3.51), respectively, among high seafood/fish eaters. Compared with heavy smokers with a low seafood/fish intake, light smokers with a high seafood/fish intake had substantially reduced risk of CHD (hazard ratio = 0.57, 95% CI: 0.32, 0.98). High seafood/fish intake attenuated the positive association between smoking and risk of CHD.

Long-chain n-3 polyunsaturated fatty acids intake and cardiovascular disease mortality risk in Japanese: a 24-year follow-up of NIPPON DATA80

BACKGROUND

Dietary intake of long-chain n-3 PUFA (LCn3FA) among Japanese is generally higher than that in Western populations. However, little is known whether an inverse association of LCn3FA with cardiovascular disease (CVD) risk exists in a population with higher LCn3FA intake.

OBJECTIVE

To investigate the association between LCn3FA intake and the long-term risk of CVDs in a Japanese general population.

METHODS

We followed-up a total of 9190 individuals (56.2% women, mean age 50.0 years) randomly selected from 300 areas across Japan and free from CVDs at baseline. Dietary LCn3FA intake was estimated using household weighed food records. Cox models were used to calculate multivariate-adjusted hazard ratios (HR) and confidence intervals (CI) according to sex specific quartiles of LCn3FA intake.

RESULTS

During 24-year follow-up (192,897 person-years), 879 cardiovascular deaths were observed. The median daily intake of LCn3FA was 0.37% kcal (0.86 g/day). Adjusted HR for CVD mortality was lower in the highest quartile of LCn3FA intake (HR 0.80; 95% CI 0.66-0.96) compared with the lowest quartile, and the trend was statistically significant (P = 0.038). The similar but statistically non-significant trends were observed for coronary heart disease death and stroke death. In analyses by age groups, the inverse associations of LCn3FA intake with the risk of total CVD death and stroke death were significant in younger individuals (30-59 years at baseline).

CONCLUSION

LCn3FA intake was inversely and independently associated the long-term risk of total CVD mortality in a representative sample of Japanese with high LCn3FA intake.

Oxidation of marine omega-3 supplements and human health

Marine omega-3 rich oils are used by more than a third of American adults for a wide range of purported benefits including prevention of cardiovascular disease. These oils are highly prone to oxidation to lipid peroxides and other secondary oxidation products. Oxidized oils may have altered biological activity making them ineffective or harmful, though there is also evidence that some beneficial effects of marine oils could be mediated through lipid peroxides. To date, human clinical trials have not reported the oxidative status of the trial oil. This makes it impossible to understand the importance of oxidation to efficacy or harm. However, animal studies show that oxidized lipid products can cause harm. Oxidation of trial oils may be responsible for the conflicting omega-3 trial literature, including the prevention of cardiovascular disease. The oxidative state of an oil can be simply determined by the peroxide value and anisidine value assays. We recommend that all clinical trials investigating omega-3 harms or benefits report the results of these assays; this will enable better understanding of the benefits and harms of omega-3 and the clinical importance of oxidized supplements.

Erythrocyte omega-3 fatty acids increase and linoleic acid decreases with age: observations from 160,000 patients

BACKGROUND

The fatty acid (FA) composition of the red blood cell (RBC) has been reported to provide prognostic information regarding risk for coronary heart disease (CHD). In particular, the Omega-3 Index (RBC eicosapentaenoic acid+docosahexaenoic acid, EPA+DHA) has been shown to be independently and inversely related to risk for sudden cardiac death and for acute coronary syndromes. Higher linoleic acid (n-6) and lower trans FA levels have also been associated with improved CHD outcomes. Accordingly, the RBC FA panel has recently been introduced in routine clinical laboratory testing.

OBJECTIVE

The purpose of this study was to define age- and gender-based norms for RBC FA levels.

METHODS

RBC FA profiles from about 160,000 patients (48% from males, 52% from females) were measured at Health Diagnostic Laboratory. These data were used to create age decade and gender-specific norms (percentiles). FA values were expressed as a percent of total identified FA.

RESULTS

Compared to men, women generally had higher C18 trans levels, and between the ages of 10-29 years, they had DHA and lower EPA levels. Among the major FA classes, saturated (41% of total) and trans (∼0.85%) fats did not vary appreciably by age, whereas monounsaturated fats tended to rise slightly. Of the two major n-6 polyunsaturates, arachidonic and linoleic acids, the former was unchanged across decades (16.4% abundance) whereas the latter decreased by about 2 percentage points (13.0-11.1%). The overall median Omega-3 Index was 4.5%, and across the decades it increased by about 1.5 percentage points. The Omega-3 Index and linoleic acid stabilized after age 70.

CONCLUSION

Whereas RBC saturated, mono- and polyunsaturated FA levels are generally stable across the lifespan, there is a shift in the composition of the latter, with an increase in the Omega-3 Index and a decrease in linoleic acid. Higher DHA and lower EPA levels in younger women is consistent with enhanced conversion of EPA to DHA during the early reproductive years. The availability of RBC FA norms will facilitate research into the relationships between altered FA status and human disease, and will help physicians evaluate the n-3 FA status of their patients.

Fish consumption and risk of stroke and its subtypes: accumulative evidence from a meta-analysis of prospective cohort studies

BACKGROUND/OBJECTIVES

To provide a reliable assessment of the hypothesized association of fish consumption with stroke risk accumulatively, an updated meta-analysis of published prospective cohort studies was conducted.

SUBJECTS/METHODS

Prospective cohort studies through April 2012 in peer-reviewed journals indexed in MEDLINE and EMBASE were selected. Additional information was retrieved through Google or a search of the reference list in relevant articles. The main outcome measure was the weighted hazards ratio (HR) and corresponding 95% confidence interval (CI) for incident stroke according to fish consumption using a random-effects model.

RESULTS

A database was derived from 16 eligible studies (19 cohorts), including 402,127 individuals (10,568 incident cases) with an average 12.8 years of follow-up. Compared with those who never consumed fish or ate fish <1/month, the pooled adjusted HRs of total stroke risk were 0.97 (95% CI, 0.87-1.08), 0.86 (0.80-0.93), 0.91 (0.85-0.98) and 0.87 (0.79-0.96) for those who consumed fish 1-3/month, 1/week, 2-4/week and ~5/week, respectively (P(linear trend) = 0.09; P(nonlinear trend) = 0.02). Study location was a modifier. An inverse association between fish intake and stroke incidence was only found by studies conducted in North America. The modest inverse associations were more pronounced with ischemic stroke and were attenuated with hemorrhagic stroke.

CONCLUSIONS

Accumulated evidence generated from this meta-analysis suggests that fish intake may have a protective effect against the risk of stroke, particularly ischemic stroke.

Significant inverse association of marine n-3 fatty acids with plasma fibrinogen levels in Japanese in Japan but not in whites or Japanese Americans

BACKGROUND/OBJECTIVES

Numerous studies reported beneficial effects of marine n-3 fatty acids (n-3 FAs) on cardiovascular disease (CVD) and its risk factors. However, the association of marine n-3 FAs with plasma fibrinogen, a risk factor for CVD, remains uncertain.

SUBJECTS/METHODS

In a population-based, cross-sectional study of 795 men aged 40-49 without CVD (262 whites in Allegheny County, Pennsylvania, USA, 302 Japanese in Kusatsu, Japan and 229 Japanese Americans in Honolulu, Hawaii, USA), we examined the association of marine n-3 FAs with plasma fibrinogen. Serum FAs were measured by capillary gas-liquid chromatography. Marine n-3 FAs were defined as the sum of docosahexaenoic, eicosapentaenoic and docosapentaenoic acids. Plasma fibrinogen was measured by an automated clot-rate assay. Multiple linear regression analyses were performed to assess the association.

RESULTS

White, Japanese and Japanese-American men had mean marine n-3 FAs levels of 3.47%, 8.78% and 4.46%, respectively. Japanese men had a significant inverse association of marine n-3 FAs with fibrinogen (standardized regression coefficient of -0.11, P=0.049), after adjusting for age, body-mass index and current smoking. The significant inverse association remained after further adjusting for diabetes, C-reactive protein, triglycerides and other variables. White or Japanese-American men did not show a significant association.

CONCLUSIONS

We observed the significant inverse association of marine n-3 FAs with fibrinogen in Japanese, but not in whites or Japanese Americans. The observation suggests that marine n-3 FAs at very high levels, as seen in the Japanese, may decrease plasma fibrinogen levels.

Fish Consumption and the Risk of Stroke

Background and Purpose—

Fish consumption has been postulated to reduce the risk of stroke. We conducted a dose–response meta-analysis to summarize the evidence from prospective studies regarding the association between fish consumption and stroke risk.

Methods—

Pertinent studies were identified by searching Embase and PubMed through May 2011 and by reviewing the references of retrieved articles. We included prospective studies that reported relative risks with 95% CIs of stroke for ≥3 categories of fish consumption. Results were combined using a random-effects model.

Results—

Fifteen prospective studies, with 9360 stroke events among 383 838 participants, were included. An increment of 3 servings/week in fish consumption was associated with a 6% reduction in risk of total stroke (relative risk, 0.94; 95% CI, 0.89–0.99) without heterogeneity among studies ( P =0.15, I 2 =25.7%). Among 9 studies with results for stroke subtypes, the relative risks were 0.90 (95% CI, 0.84–0.97) for ischemic stroke and 0.90 (95% CI, 0.76–1.06) for hemorrhagic stroke.

Conclusions—

These findings indicate that fish consumption is weakly inversely associated with the risk of stroke.

Fish consumption and CHD mortality: an updated meta-analysis of seventeen cohort studies

OBJECTIVE

Results of studies on fish consumption and CHD mortality are inconsistent. The present updated meta-analysis was conducted to investigate the up-to-date pooling effects.

DESIGN

A random-effects model was used to pool the risk estimates. Generalized least-squares regression and restricted cubic splines were used to assess the possible dose-response relationship. Subgroup analyses were conducted to examine the sources of heterogeneity.

SETTING

PubMed and ISI Web of Science databases up to September 2010 were searched and secondary referencing qualified for inclusion in the study.

SUBJECTS

Seventeen cohorts with 315,812 participants and average follow-up period of 15·9 years were identified.

RESULTS

Compared with the lowest fish intake (<1 serving/month or 1-3 servings/month), the pooled relative risk (RR) of fish intake on CHD mortality was 0·84 (95% CI 0·75, 0·95) for low fish intake (1 serving/week), 0·79 (95% CI 0·67, 0·92) for moderate fish intake (2-4 servings/week) and 0·83 (95% CI 0·68, 1·01) for high fish intake (>5 servings/week). The dose-response analysis indicated that every 15 g/d increment of fish intake decreased the risk of CHD mortality by 6% (RR = 0·94; 95% CI 0·90, 0·98). The method of dietary assessment, gender and energy adjustment affected the results remarkably.

CONCLUSIONS

Our results indicate that either low (1 serving/week) or moderate fish consumption (2-4 servings/week) has a significantly beneficial effect on the prevention of CHD mortality. High fish consumption (>5 servings/week) possesses only a marginally protective effect on CHD mortality, possibly due to the limited studies included in this group.

Dietary omega-3 fatty acid, ratio of omega-6 to omega-3 intake, inflammation, and survival in long-term hemodialysis patients

BACKGROUND

Mortality in long-term hemodialysis patients is high, mostly attributed to cardiovascular events, and may be related to chronic inflammation. We hypothesized that the anti-inflammatory benefits of higher dietary intake of omega-3 compared with omega-6 polyunsaturated fatty acids may modulate the inflammatory processes and decrease death risk.

STUDY DESIGN

Prospective cohort study using linear and Cox proportional regressions.

SETTING & PARTICIPANTS

145 hemodialysis patients from 8 DaVita dialysis clinics in Southern California in 2001-2007.

PREDICTORS

Intake of dietary omega-3 and ratio of omega-6 to omega-3 using 3-day food record supplemented by dietary interview.

OUTCOMES

1-year change in serum C-reactive protein (CRP) level and 6-year survival.

RESULTS

Patients were aged 53 ± 14 years (mean ± SD) and included 43% women and 42% African Americans. Median dietary omega-3 intake, ratio of omega-6 to omega-3 intake, baseline serum CRP level, and change in CRP level over 1 year were 1.1 (25th-75th percentile, 0.8-1.6) g/d, 9.3 (25th-75th percentile, 7.6-11.3), 3.1 (25th-75th percentile, 0.8-6.8) mg/L, and +0.2 (25th-75th percentile, -0.4 to +0.8) mg/L, respectively. In regression models adjusted for case-mix, dietary calorie and fat intake, body mass index, and history of hypertension, each 1-unit higher ratio of omega-6 to omega-3 intake was associated with a 0.55-mg/L increase in serum CRP level (P = 0.03). In the fully adjusted model, death HRs for the first (1.7-<7.6), second (7.6-<9.3), third (9.3-<11.3), and fourth (11.3-17.4) quartiles of dietary omega-6 to omega-3 ratio were 0.39 (95% CI, 0.14-1.18), 0.30 (95% CI, 0.09-0.99), 0.67 (95% CI, 0.25-1.79), and 1.00 (reference), respectively (P for trend = 0.06).

LIMITATIONS

3-day food record may underestimate actual dietary fat intake at an individual level.

CONCLUSIONS

Higher dietary omega-6 to omega-3 ratio appears to be associated with both worsening inflammation over time and a trend toward higher death risk in hemodialysis patients. Additional studies including interventional trials are needed to examine the association of dietary fatty acids with clinical outcomes in these patients.

Impact of low v. moderate intakes of long-chain n-3 fatty acids on risk of coronary heart disease

The objective of the present study was to determine whether the consumption of ≥ 250 v. < 250 mg of the long-chain n-3 fatty acids (n-3 LCFA) per d is associated with a reduction in the risk of fatal and non-fatal CHD in individuals with no prior history of CHD. A comprehensive and systematic review of the published scientific literature resulted in the identification of eight prospective studies (seven cohorts and one nested case–control study) that met predefined inclusion criteria. Relative to the consumption of < 250 mg n-3 LCFA per d, the consumption of ≥ 250 mg/d was associated with a significant 35·1 % reduction in the risk of sudden cardiac death and a near-significant 16·6 % reduction in the risk of total fatal coronary events, while the risk of non-fatal myocardial infarction was not significantly reduced. In several meta-analyses, which were based on US studies, risk of CHD death was found to be dose-dependently reduced by the n-3 LCFA, with further risk reductions observed with intakes in excess of 250 mg/d. Prospective observational and intervention data from Japan, where intake of fish is very high, suggest that n-3 LCFA intakes of 900 to 1000 mg/d and greater may confer protection against non-fatal myocardial infarction. Thus, the intake of 250 mg n-3 LCFA per d may, indeed, be a minimum target to be achieved by the general population for the promotion of cardiovascular health.

Docosahexaenoic acid: brain accretion and roles in neuroprotection after brain hypoxia and ischemia

PURPOSE OF REVIEW

With important effects on neuronal lipid composition, neurochemical signaling and cerebrovascular pathobiology, docosahexaenoic acid (DHA), a n-3 polyunsaturated fatty acid, may emerge as a neuroprotective agent against cerebrovascular disease. This paper examines pathways for DHA accretion in brain and evidence for possible roles of DHA in prophylactic and therapeutic approaches for cerebrovascular disease.

RECENT FINDINGS

DHA is a major n-3 fatty acid in the mammalian central nervous system and enhances synaptic activities in neuronal cells. DHA can be obtained through diet or to a limited extent via conversion from its precursor, α-linolenic acid (α-LNA). DHA attenuates brain necrosis after hypoxic ischemic injury, principally by modulating membrane biophysical properties and maintaining integrity in functions between presynaptic and postsynaptic areas, resulting in better stabilizing intracellular ion balance in hypoxic-ischemic insult. Additionally, DHA alleviates brain apoptosis, by inducing antiapoptotic activities such as decreasing responses to reactive oxygen species, upregulating antiapoptotic protein expression, downregulating apoptotic protein expression, and maintaining mitochondrial integrity and function.

SUMMARY

DHA in brain relates to a number of efficient delivery and accretion pathways. In animal models DHA renders neuroprotection after hypoxic-ischemic injury by regulating multiple molecular pathways and gene expression.

Fish consumption and risk of stroke in Swedish women

BACKGROUND

Epidemiologic studies of fish consumption in relation to risk of stroke have yielded inconsistent results.

OBJECTIVE

In this study, we examined the association between fish consumption and stroke incidence in women.

DESIGN

We analyzed data from a population-based prospective cohort of 34,670 women in the Swedish Mammography Cohort who were free of cardiovascular disease and cancer at baseline. Information on fish consumption was obtained by a self-administered questionnaire in 1997. Incident cases of stroke were ascertained from the Swedish Hospital Discharge Registry. We used Cox proportional hazards regression to estimate relative risks (RRs) and 95% CIs.

RESULTS

Over a mean follow-up of 10.4 y, we ascertained 1680 incident cases of stroke, including 1310 cerebral infarctions, 233 hemorrhagic strokes, and 137 unspecified strokes. Fish consumption was significantly inversely associated with risk of total stroke but not with cerebral infarction or hemorrhagic stroke. Compared with women in the lowest quintile of fish consumption (<1.0 serving of fish/wk), the multivariable RR of total stroke for women in the highest quintile (>3.0 servings of fish/wk) was 0.84 (95% CI: 0.71, 0.98; P for trend = 0.049). Consumption of lean fish but not of other fish types was inversely associated with risk of stroke. The multivariable RR of total stroke was 0.67 (95% CI: 0.49, 0.93; P for trend = 0.07) for ≥3 servings of lean fish/wk compared with that for no consumption.

CONCLUSION

These results suggest that the consumption of fish, especially of lean fish, may reduce risk of stroke in women. This trial was registered at clinicaltrials.gov as NCT01127698.

Relationships between plasma fatty acid composition and coronary artery disease

AIM

The Japan EPA Lipid Intervention Study (JELIS) was the first prospective randomized clinical trial to demonstrate prevention of coronary events by pure eicosapentaenoic acid (EPA). The aim of this study was to examine the relationships between various plasma fatty acid concentrations and the risk of coronary events in JELIS participants.

METHODS

In 15,534 participants, we calculated the hazard ratio for major coronary events (sudden cardiac death, fatal or nonfatal myocardial infarction, unstable angina pectoris, and angioplasty/stenting or coronary artery bypass grafting) relative to the on-treatment average level of plasma fatty acids with the Cox proportional hazard model.

RESULTS

As a result of EPA intervention, the plasma EPA concentration increased, but the docosahexaenoic acid (DHA) concentration did not. The other fatty acids measured decreased slightly. The higher plasma level of EPA (hazard ratio=0.83, p=0.049, in all participants and hazard ratio=0.71, p=0.018, in the EPA intervention group), but not of DHA, was inversely associated with the risk of major coronary events. The associations between other fatty acids and the risk of major coronary events were not significant. In all JELIS participants, the risk of major coronary events was significantly decreased (20%) in the group with high (150 µg/mL or more) on-treatment plasma EPA concentration compared with that in the low (less than 87 µg/mL) group.

CONCLUSION

The risk of coronary artery disease is influenced by variations in plasma fatty acid composition. Among n-3 polyunsaturated fatty acids, EPA and DHA exhibited differences in the correlation with the risk of major coronary events.

Blood eicosapentaenoic and docosahexaenoic acids predict all-cause mortality in patients with stable coronary heart disease: the Heart and Soul study

BACKGROUND

Omega-3 fatty acid (n-3 FA) blood levels and intake have been inversely associated with risk for sudden cardiac death, but their relationship with all-cause mortality is unclear. The purpose of this study was to determine the extent to which baseline blood n-3 FA levels are associated with reduced risk for all-cause mortality in patients with stable coronary heart disease.

METHODS AND RESULTS

The Heart and Soul study used a prospective cohort design with a median follow-up of 5.9 years. Patients were recruited between 2000 and 2002 from 12 outpatient facilities in the San Francisco Bay Area. Standard cardiovascular risk factors, demographics, socioeconomic status, health behaviors, and inflammatory markers were collected at baseline. Fasting blood levels of eicosapentaenoic and docosahexaenoic acids were measured and expressed as a percent of total blood FAs. Vital status was assessed with annual telephone interviews and confirmed by review of death certificates. There were 237 deaths among 956 patients. Cox proportional hazards models were used to evaluate the extent to which blood eicosapentaenoic and docosahexaenoic acids were independently associated with all cause mortality. Compared with patients having baseline eicosapentaenoic and docosahexaenoic acids levels below the median (<3.6%), those at or above the median had a 27% decreased risk of death (hazard ratio, 0.73; 95% confidence interval, 0.56-0.94). This association was unaffected by adjustment for age, sex, ethnicity, center, socioeconomic status, traditional cardiovascular risk factors, and inflammatory markers (hazard ratio, 0.74; 95% confidence interval, 0.55-1.00, P<0.05).

CONCLUSIONS

In these outpatients with stable coronary heart disease, blood n-3 FA levels were inversely associated with total mortality independent of standard and emerging risk factors, suggesting that reduced tissue n-3 FA levels may adversely impact metabolism.

Polyunsaturated fatty acid levels of serum and red blood cells in apparently healthy Japanese subjects living in an urban area

AIM

We assessed levels of polyunsaturated fatty acid (PUFA) in serum and red blood cells (RBCs) among groups stratified by generation and its clinical significance in Japanese subjects living in an urban area.

METHODS

We enrolled 200 apparently healthy Japanese (126 males, mean age: 50.3+/-9.2 years) living in an urban area. Levels of PUFA, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), and dihomo-gamma-linolenic acid (DGLA) in serum and RBCs were measured for each generation (G1 <35y, G2 35y-<45y, G3 45y-<55y, G4 55y-<65y, G5>or=65y).

RESULTS

No significant differences in EPA, DHA, AA, or EPA/AA were observed between males and females. After dividing into generations, stepwise increases in EPA and DHA, but not DGLA or AA, were observed in serum (all p<0.0001). EPA/AA ratios were stepwisely increased in serum (mean: G1:0.26, G2:0.29, G3:0.43, G4:0.58, G5:0.68, p<0.0001) and RBCs (mean: G1:0.10, G2:0.09, G3:0.15, G4:0.20, G5:0.23, p<0.0001). Positive correlations of EPA (r=0.83), DHA (r=0.55), DGLA (r=0.54), AA (r=0.29), and EPA/AA (r=0.91) were demonstrated between serum and RBCs. In addition, a significant positive correlation between EPA/AA ratios and insulin sensitivity as well as a negative correlation between those ratios and insulin resistance were observed in subjects with metabolic syndrome.

CONCLUSION

Low levels of EPA/AA, which were associated with insulin resistance, were demonstrated in young Japanese adults living in an urban area.

Alcohol intake and 19-year mortality in diabetic men: NIPPON DATA80

Although moderate alcohol intake in diabetic Caucasians is associated with a reduction in coronary heart disease mortality, no study in Japanese with diabetes has examined the association between alcohol intake and mortality outcomes. We analyzed the relationship between alcohol intake and all-cause and cause-specific mortality using the database from NIPPON DATA80. At the baseline in 1980, data on history, lifestyle, and physical examinations were collected on study participants aged 30 years and older from randomly selected areas in Japan. After excluding participants with comorbidities, we followed 4,018 male participants (3,614 nondiabetics, 195 with impaired glucose tolerance and 209 diabetic) for 19 years. During the 19 years of follow-up, there were 990 deaths; 328 were from cardiovascular disease and 157 from all-heart diseases. With the never-drinking category serving as a reference, the Cox multivariate-adjusted hazard ratios for non-daily and daily drinkers for cardiovascular mortality were 0.43 (95% confidence intervals: 0.19-0.95) and 0.45 (0.25-0.80), respectively, and 0.33 (0.12-0.91) and 0.31 (0.15-0.67) for all-heart disease mortality in the combined impaired glucose tolerance and diabetic Japanese men. Alcohol drinking in men with glucose intolerance was associated with a significant reduction in cardiovascular and all-heart disease mortality as seen in the general population in Japan.

Towards establishing dietary reference intakes for eicosapentaenoic and docosahexaenoic acids

There is considerable interest in the impact of (n-3) long-chain PUFA in mitigating the morbidity and mortality caused by chronic diseases. In 2002, the Institute of Medicine concluded that insufficient data were available to define Dietary Reference Intakes (DRI) for eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), noting only that EPA and DHA could contribute up to 10% toward meeting the Adequate Intake for alpha-linolenic acid. Since then, substantial new evidence has emerged supporting the need to reassess this recommendation. Therefore, the Technical Committee on Dietary Lipids of the International Life Sciences Institute North America sponsored a workshop on 4-5 June 2008 to consider whether the body of evidence specific to the major chronic diseases in the United States--coronary heart disease (CHD), cancer, and cognitive decline--had evolved sufficiently to justify reconsideration of DRI for EPA+DHA. The workshop participants arrived at these conclusions: 1) consistent evidence from multiple research paradigms demonstrates a clear, inverse relation between EPA+DHA intake and risk of fatal (and possibly nonfatal) CHD, providing evidence that supports a nutritionally achievable DRI for EPA+DHA between 250 and 500 mg/d; 2) because of the demonstrated low conversion from dietary ALA, protective tissue levels of EPA+DHA can be achieved only through direct consumption of these fatty acids; 3) evidence of beneficial effects of EPA+DHA on cognitive decline are emerging but are not yet sufficient to support an intake level different from that needed to achieve CHD risk reduction; 4) EPA+DHA do not appear to reduce risk for cancer; and 5) there is no evidence that intakes of EPA+DHA in these recommended ranges are harmful.