Animal protein, animal fat, and cholesterol intakes and risk of cerebral infarction mortality in the adult health study

Dietary intake of plant- and animal-derived protein and incident cardiovascular diseases: the pan-European EPIC-CVD case-cohort study

BACKGROUND

Epidemiological evidence suggests that a potential association between dietary protein intake and cardiovascular disease (CVD) may depend on the protein source, that is, plant- or animal-derived, but past research was limited and inconclusive.

OBJECTIVES

To evaluate the association of dietary plant- or animal-derived protein consumption with risk of CVD, and its components ischemic heart disease (IHD) and stroke.

METHODS

This analysis in the European Prospective Investigation into Cancer and Nutrition (EPIC)-CVD case-cohort study included 16,244 incident CVD cases (10,784 IHD and 6423 stroke cases) and 15,141 subcohort members from 7 European countries. We investigated the association of estimated dietary protein intake with CVD, IHD, and stroke (total, fatal, and nonfatal) using multivariable-adjusted Prentice-weighted Cox regression. We estimated isocaloric substitutions of replacing fats and carbohydrates with plant- or animal-derived protein and replacing food-specific animal protein with plant protein. Multiplicative interactions between dietary protein and prespecified variables were tested.

RESULTS

Neither plant- nor animal-derived protein intake was associated with incident CVD, IHD, or stroke in adjusted analyses without or with macronutrient-specified substitution analyses. Higher plant-derived protein intake was associated with 22% lower total stroke incidence among never smokers [HR 0.78, 95% confidence intervals (CI): 0.62, 0.99], but not among current smokers (HR 1.08, 95% CI: 0.83, 1.40, P-interaction = 0.004). Moreover, higher plant-derived protein (per 3% total energy) when replacing red meat protein (HR 0.52, 95% CI: 0.31, 0.88), processed meat protein (HR 0.39, 95% CI: 0.17, 0.90), and dairy protein (HR 0.54, 95% CI: 0.30, 0.98) was associated with lower incidence of fatal stroke.

CONCLUSION

Plant- or animal-derived protein intake was not associated with overall CVD. However, the association of plant-derived protein consumption with lower total stroke incidence among nonsmokers, and with lower incidence of fatal stroke highlights the importance of investigating CVD subtypes and potential interactions. These observations warrant further investigation in diverse populations with varying macronutrient intakes and dietary patterns.

Associations between Cholesterol Intake, Food Sources and Cardiovascular Disease in Chinese Residents

Cholesterol is a nutrient commonly found in the human diet. The relationship between dietary cholesterol, its sources, and cardiovascular disease (CVD) is still a topic of debate. This study aimed to investigate the association between dietary cholesterol, its sources, and cardiovascular events in a Chinese population. The present study analyzed data from the China Health and Nutrition Survey (CHNS) cohort between 1991 and 2015. This study analyzed data from 3903 participants who were 40 years of age or older at baseline and had no history of cardiovascular disease, diabetes, or hypertension. During a median follow-up of 14 years, 503 cardiovascular disease events were identified through follow-up questionnaires administered every 2-3 years. The events included fatal and nonfatal coronary heart disease, stroke, heart failure, and other cardiovascular disease deaths. Cox regression was used to estimate risk ratios (HR) for CVD events after adjusting for demographic, socioeconomic, and behavioral factors. It was discovered that sources of dietary cholesterol varied among different subgroups of the population. The top three sources of cholesterol among all participants were eggs, red meat, and seafood, accounting for 57.4%, 28.2%, and 9.0% of total daily cholesterol intake, respectively. The present study found that there was a significant association between total dietary cholesterol intake, and the risk of developing cardiovascular disease (adjusted HR [95% CI]: total cholesterol (highest and lowest quartiles compared) 1.57 [1.17-2.11]). Cholesterol from poultry, seafood, and eggs was also significantly associated with a reduced risk of CVD (adjusted HR [95% CI]: poultry 0.18 [0.04-0.82], seafood 0.11 [0.02-0.54], and eggs 0.16 [0.03-0.73]). After adjusting for daily caloric intake, daily fat intake, and daily saturated fat intake, the previously observed association between red meat cholesterol and cardiovascular events (unadjusted HR [95% CI]: 0.44 [0.35-0.55]) was no longer statistically significant (adjusted HR [95% CI]: 0.21 [0.04-1.01]).

Dietary Macronutrient Intake and Cardiovascular Disease Risk and Mortality: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies

Many epidemiological studies have evaluated the intake of macronutrients and the risk of mortality and cardiovascular disease (CVD). However, current evidence is conflicting and warrants further investigation. Therefore, we carried out an umbrella review to examine and quantify the potential dose-response association of dietary macronutrient intake with CVD morbidity and mortality. Prospective cohort studies from PubMed, Embase, and CENTRAL were reviewed, which reported associations of macronutrients (protein, fat, and carbohydrate) with all-cause, CVD, cancer mortality, or CVD events. Multivariable relative risks (RR) were pooled, and heterogeneity was assessed. The results of 124 prospective cohort studies were included in the systematic review and 101 in the meta-analysis. During the follow-up period from 2.2 to 30 years, 506,086 deaths and 79,585 CVD events occurred among 5,107,821 participants. High total protein intake was associated with low CVD morbidity (RR 0.88, 95% confidence interval 0.82-0.94), while high total carbohydrate intake was associated with high CVD morbidity (1.08, 1.02-1.13). For fats, a high intake of total fat was associated with a decreased all-cause mortality risk (0.92, 0.85-0.99). Saturated fatty acid intake was only associated with cancer mortality (1.10, 1.06-1.14); Both monounsaturated fatty acid (MUFA) and polyunsaturated fatty acids (PUFA) intake was associated with all-cause mortality (MUFA: 0.92, 0.86-0.98; PUFA: 0.91, 0.86-0.96). This meta-analysis supports that protein intake is associated with a decreased risk of CVD morbidity, while carbohydrate intake is associated with an increased risk of CVD morbidity. High total fat intake is associated with a low risk of all-cause mortality, and this effect was different in an analysis stratified by the type of fat.

The 2023 Taiwan Stroke Society Guidelines for the management of patients with intracranial atherosclerotic disease

Intracranial atherosclerotic disease (ICAD) is a major cause of ischemic stroke, especially in Asian populations, which has a high risk of recurrent stroke and cardiovascular comorbidities. The present guidelines aim to provide updated evidence-based recommendations for diagnosis and management of patients with ICAD. Taiwan Stroke Society guideline consensus group developed recommendations for management of patients with ICAD via consensus meetings based on updated evidences. Each proposed class of recommendation and level of evidence was approved by all members of the group. The guidelines cover six topics, including (1) epidemiology and diagnostic evaluation of ICAD, (2) nonpharmacological management of ICAD, (3) medical therapy for symptomatic ICAD, (4) endovascular thrombectomy and rescue therapy for acute ischemic stroke with underlying ICAD, (5) endovascular interventional therapy for postacute symptomatic intracranial arterial stenosis, and (6) surgical treatment of chronic symptomatic intracranial arterial stenosis. Intensive medical treatment including antiplatelet therapy, risk factor control, and life style modification are essential for patients with ICAD.

Investigation the interaction of dietary fat quality indices and the MC4R gene in metabolically healthy and unhealthy overweight and obese women

Obesity has become a common global problem. Some obese people can be metabolically healthy. Gene-environment interaction can be important in this context. This study aimed to assess the interaction between dietary fat quality indices and the Melanocortin 4 receptor (MC4R) gene in metabolically healthy and unhealthy overweight and obese women. This cross-sectional study was conducted on 279 women with overweight and obesity. The definition of metabolically healthy and unhealthy phenotypes was done according to Karelis criteria. Dietary assessment was done using a 147-item validated semi-quantitative food frequency questionnaire and dietary fat quality was assessed by cholesterol-saturated fat index (CSI) and the ratio of omega-6/omega-3 (N6/N3) essential fatty acids. MC4R was genotyped by polymerase chain reaction-restriction fragment length polymorphism technique. A generalized linear model was used to evaluate the interaction between dietary fat quality indices and the MC4R gene in both crude and adjusted models. Study subjects with higher ratio of N6/N3 had higher homeostatic model assessment for insulin resistance (HOMA IR) index (P = 0.03) and other variables showed no difference according to the tertile of CSI and N6/N3. Participants with the C allele of MC4R rs17782313 had lower height (P < 0.001) and higher HOMA index (P = 0.01). We found that the CC genotype of MC4R interacts with the N6/N3 ratio on the metabolically unhealthy phenotype in the crude model (β = 9.94, CI 2.49-17.39, P = 0.009) and even after adjustment for all confounders (β = 9.002, CI 1.15-16.85, P = 0.02, β =  - 12.12, CI 2.79-21.46, P = 0.01). The data of this study can justify one inconsistency observed in society, regarding dietary recommendations about metabolic health status. Those with CC genotype, are more likely to have an unhealthy phenotype with an increase in N6/N3 as one fat quality indices than those who do not have CC genotype. We found the interaction of dietary fat quality indices such as N6/N3 and the MC4R gene in metabolically unhealthy overweight and obese women.

Red Meat Consumption and Risk of Cardio-Cerebrovascular Disease in Chinese Older Adults

Associations between red meat consumption and cardio-cerebrovascular diseases (CCVDs) are mostly studied in Western populations but not in Chinese or elderly. This prospective study investigated adults ≥65 years from the China Kadoorie Biobank (CKB). Associations between red meat consumption and CCVD, ischemic stroke/transient ischemic attack (TIA), CCVD mortality, and all-cause mortality were determined by Cox regression. A total of 59,980 participants were analyzed, 14,715 (24.53%) of whom ate red meat daily, 9,843 (16.41%) ate red meat 4-6 days/week, 23,472 (39.13%) ate red meat 1-3 days/week, and 11,950 (19.92%) ate red meat less than 1 day/week. Average amount of red meat usual consumption was 38 g/day. After adjustment, per 50 g/day higher red meat consumption at baseline was significantly associated with increased incident CCVD (aHR = 1.10) among high-income subjects (≥ 10,000 RMB) and urban residents (aHR = 1.12). Per 50 g/day higher baseline red meat consumption was significantly associated with increased ischemic stroke/TIA in urban residents (aHR = 1.08) but decreased risk in rural residents (aHR = 0.84). Higher baseline red meat consumption was associated with lower CCVD mortality in the poorest (aHR = 0.78) and rural residents (aHR = 0.72) and lower all-cause mortality in the poorest (aHR = 0.82) and rural residents (aHR = 0.80). In general, among older adults in China, higher red meat intake independently predicted increased CCVD among urban and high-income individuals but not poor ones. Higher red meat intake appears to be protective against mortality in rural and low-income subjects. Socioeconomic status is a crucial modifying factor on the association between red meat consumption and adverse cardiovascular outcomes in China.

Heart diseases, hypertension and effects of antihypertensive medications: Is hypertension a true risk factor of heart diseases?

Background

Heart diseases (HD) are the leading cause of deaths in the world. Many studies have been done on the relationships among hypertension, HD and antihypertensive medications. Most of the studies find that hypertension is a significant risk factor of HD, but there are some studies in which hypertension is not a risk factor. As antihypertensive medications are routinely prescribed to prevent HD, it is necessary to evaluate the effects of these and other risk factors of HD.

Data and methods

The relationship between hypertension and HD was analyzed using 6,773,464 medical checkups obtained from the JMDC Claims Database obtained from January 2005 to September 2019. Factors potentially affecting HD, including blood pressures (BP) and usage of antihypertensive medications, were evaluated using 2,861,769 observations. To avoid the causality problem, probit models were used to analyze the probability of an individual who had no history of HD at year t developing HD by year t + 1.

Results

A positive relation between systolic blood pressure (SBP) and HD was found in the equation without any other covariates. However, the significant relation between HD and BP disappeared when the models contained various other factors as covariates. When a 10-year age or longer interval was used in the model, a positive relation between the two variables was found, suggesting that SBP works as a proxy variable. Taking antihypertensive medications greatly increases the probability of developing HD in the next year. Higher levels of cholesterols decrease the probability of developing HD.

Conclusion

Unlike many previous studies, no significant relationship between HD and hypertension was found in the models containing multiple covariates. The accepted relation might actually be spurious, and it is important to select covariates carefully. Taking antihypertensive medications appears to increase the probability of developing HD in the next year, suggesting the need for further research and greater caution in the use of antihypertensive medications.

Egg and Dietary Cholesterol Intake and Risk of All-Cause, Cardiovascular, and Cancer Mortality: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies

Objective

This systematic review and meta-analysis of prospective cohort studies examined the associations between egg and dietary cholesterol intake and the risk of mortality from all causes, including cardiovascular disease (CVD) and cancer.

Methods

We searched PubMed, Scopus, ISI Web of Knowledge, and Google Scholar until April 2021, as well as references to the relevant articles retrieved. Random-effects models were used to calculate summary relative risk (RR) and 95% confidence intervals (CIs) for the highest vs. lowest categories of egg and dietary cholesterol intake. Also, linear and non-linear dose–response analyses were conducted to examine the dose-response relationships.

Results

We included 55 studies, comprising data from 2,772,486 individuals with 228,425, 71,745, and 67,211 cases of all-cause, CVD, and cancer mortality, respectively. Intake of each additional egg per day was associated with a 7% higher risk of all-cause (1.07, 95% CI: 1.02–1.12, I² = 84.8%) and a 13% higher risk of cancer mortality (1.13, 95% CI: 1.06–1.20, I² = 54.2%), but was not associated with CVD mortality (1.00, 95% CI: 0.92–1.09, I² = 81.5%). Non-linear analyses showed increased risks for egg consumption of more than 1.5 and 0.5 eggs/day, respectively. Each 100 mg/day increment in dietary cholesterol intake was associated with a 6% higher risk of all-cause mortality (1.06, 95% CI: 1.03–1.08, I² = 34.5%) and a 6% higher risk of cancer mortality (1.06, 95% CI: 1.05–1.07, I² = 0%), but was not associated with CVD mortality (1.04, 95% CI: 0.99–1.10, I² = 85.9%). Non-linear analyses demonstrated elevated risks of CVD and cancer mortality for intakes more than 450 and 250 mg/day, respectively.

Conclusions and Relevance

High-dietary intake of eggs and cholesterol was associated with all-cause and cancer mortality. Little evidence for elevated risks was seen for intakes below 0.5 egg/day or 250 mg/day of dietary cholesterol. Our findings should be considered with caution because of small risk estimates and moderate between-study heterogeneity.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=252564, PROSPERO, identifier: CRD42021252564.

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.

Red and processed meat consumption and risk of incident cardiovascular disease and mortality: Isfahan cohort study

To investigate the cardiovascular risks associated with red and/or processed meat intake in a large population-based cohort study in Iran. A total of 5432 participants from the Isfahan Cohort Study (ICS) were enrolled. Diet was assessed using a validated, 48-item food frequency questionnaire. Cox proportional hazards regression models were applied to calculate hazard ratios (HRs) for the CVD risk associated with red and processed meat intake. Median follow-up was 11.2 years. Compared to the first tertile, the highest tertile of red meat intake, either alone or in combination with processed meat was associated with a 50% reduced risk of stroke (95% CI: 0.31-0.77; 95% CI: 0.33-0.82, respectively), but increased risk of CVD mortality with corresponding HRs of 1.58 (95% CI: 1.06-2.35) and 1.47 (95% CI: 1.02-2.08), respectively. Red meat and red plus processed meat intake were inversely associated with stroke risk, but positively linked with CVD mortality.

A Systematic Review of the Association Between Vegan Diets and Risk of Cardiovascular Disease

BACKGROUND

Plant-based diets are gaining attention globally due to their environmental benefits and perceived health-protective role. A vegan diet may have cardiovascular benefits; however, evidence remains conflicting and insufficiently assessed.

OBJECTIVES

We evaluated the utility of the vegan diet in cardiovascular disease (CVD) prevention.

METHODS

We conducted a systematic review of studies evaluating the association between vegan diets and cardiovascular outcomes. We searched 5 databases (Ovid MEDLINE, EMBASE, Web of Science, Scopus, and OpenGrey) through 31 October 2020. Four investigators independently screened the full texts for inclusion, assessed quality, and extracted data from published reports.

RESULTS

Out of the 5729 identified records, 7 were included, comprising over 73,000 participants, of whom at least 7661 were vegans. Three studies, with at least 73,426 individuals (including at least 7380 vegans), examined risks of primary cardiovascular events (total CVD, coronary heart disease, acute myocardial infarction, total stroke, hemorrhagic stroke, and ischemic stroke) in individuals who followed a vegan diet compared to those who did not. None of the studies reported a significantly increased or decreased risk of any cardiovascular outcome. One study suggested that vegans were at greater risk of ischemic stroke compared to individuals who consumed animal products (HR, 1.54; 95% CI, 0.95-2.48). Yet in another study, vegans showed lower common carotid artery intima-media thickness (0.56 ± 0.1 mm vs. 0.74 ± 0.1 mm in controls; P < 0.001), and in 3 studies of recurrent CVD events, vegans had 0-52% lower rates. Furthermore, endothelial function did not differ between vegans and nonvegans. Using the Grading of Recommendations Assessment, Development and Evaluation approach, evidence was deemed to be of low to very low strength/quality.

CONCLUSIONS

Among the Western populations studied, evidence weakly demonstrates associations between vegan diets and risk of CVDs, with the direction of associations varying with the specific CVD outcome tested. However, more high-quality research on this topic is needed. This study was registered at PROSPERO as CRD42019146835.

Dietary intake of total, animal, and plant proteins and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of prospective cohort studies

OBJECTIVE

To examine and quantify the potential dose-response relation between intake of total, animal, and plant protein and the risk of mortality from all causes, cardiovascular disease, and cancer.

DESIGN

Systematic review and meta-analysis of prospective cohort studies.

DATA SOURCES

PubMed, Scopus, and ISI Web of Science until December 2019, and references of retrieved relevant articles.

STUDY SELECTION

Prospective cohort studies that reported the risk estimates for all cause, cardiovascular, and cancer mortality in adults aged 18 or older.

DATA SYNTHESIS

Random effects models were used to calculate pooled effect sizes and 95% confidence intervals for the highest versus lowest categories of protein intake and to incorporate variation between studies. Linear and non-linear dose-response analyses were done to evaluate the dose-response relations between protein intake and mortality.

RESULTS

32 prospective cohort studies were included in the systematic review and 31 in the meta-analysis. During the follow-up period of 3.5 to 32 years, 113 039 deaths (16 429‬ from cardiovascular disease and 22 303‬ from cancer) occurred among 715 128 participants. Intake of total protein was associated with a lower risk of all cause mortality (pooled effect size 0.94, 95% confidence interval 0.89 to 0.99, I2=58.4%, P<0.001). Intake of plant protein was significantly associated with a lower risk of all cause mortality (pooled effect size 0.92, 95% confidence interval 0.87 to 0.97, I2=57.5%, P=0.003) and cardiovascular disease mortality (pooled hazard ratio 0.88, 95% confidence interval 0.80 to 0.96, I2=63.7%, P=0.001), but not with cancer mortality. Intake of total and animal protein was not significantly associated with risk of cardiovascular disease and cancer mortality. A dose-response analysis showed a significant inverse dose-response association between intake of plant protein and all cause mortality (P=0.05 for non-linearity). An additional 3% energy from plant proteins a day was associated with a 5% lower risk of death from all causes.

CONCLUSIONS

Higher intake of total protein was associated with a lower risk of all cause mortality, and intake of plant protein was associated with a lower risk of all cause and cardiovascular disease mortality. Replacement of foods high in animal protein with plant protein sources could be associated with longevity.

Vegetarian diet and incidence of total, ischemic, and hemorrhagic stroke in 2 cohorts in Taiwan

Objective

To determine how a vegetarian diet affects stroke incidence in 2 prospective cohorts and to explore whether the association is modified by dietary vitamin B₁₂ intake.

Methods

Participants without stroke in the Tzu Chi Health Study (cohort 1, n = 5,050, recruited in 2007–2009) and the Tzu Chi Vegetarian Study (cohort 2, n = 8,302, recruited in 2005) were followed until the end of 2014. Diet was assessed through food frequency questionnaires in both cohorts at baseline. Stroke events and baseline comorbidities were identified through the National Health Insurance Research Database. A subgroup of 1,528 participants in cohort 1 were assessed for serum homocysteine, vitamin B₁₂, and folate. Associations between vegetarian diet and stroke incidences were estimated by Cox regression with age as time scale, adjusted for sex, education, smoking, alcohol, physical activities, body mass index (only in cohort 1), hypertension, diabetes, dyslipidemia, and ischemic heart diseases.

Results

Vegetarians had lower serum vitamin B₁₂ and higher folate and homocysteine than nonvegetarians. In cohort 1, 54 events occurred in 30,797 person-years follow-up. Vegetarians (vs nonvegetarians) experienced lower risk of ischemic stroke (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.08–0.88). In cohort 2, 121 events occurred in 76,797 person-years follow-up. Vegetarians (vs nonvegetarians) experienced lower risk of overall stroke (HR, 0.52; 95% CI, 0.33–0.82), ischemic stroke (HR, 0.41; 95% CI, 0.19–0.88), and hemorrhagic stroke (HR, 034; 95% CI, 0.12–1.00). Our explorative analysis showed that vitamin B₁₂ intake may modify the association between vegetarian diet and overall stroke (p interaction = 0.046).

Conclusion

Taiwanese vegetarian diet is associated with a lower risk of ischemic and hemorrhagic strokes.

Dietary protein intake and all-cause and cause-specific mortality: results from the Rotterdam Study and a meta-analysis of prospective cohort studies

Evidence for associations between long-term protein intake with mortality is not consistent. We aimed to examine associations of dietary protein from different sources with all-cause and cause-specific mortality. We followed 7786 participants from three sub-cohorts of the Rotterdam Study, a population-based cohort in the Netherlands. Dietary data were collected using food-frequency questionnaires at baseline (1989-1993, 2000-2001, 2006-2008). Deaths were followed until 2018. Associations were examined using Cox regression. Additionally, we performed a highest versus lowest meta-analysis and a dose-response meta-analysis to summarize results from the Rotterdam Study and previous prospective cohorts. During a median follow-up of 13.0 years, 3589 deaths were documented in the Rotterdam Study. In this cohort, after multivariable adjustment, higher total protein intake was associated with higher all-cause mortality [e.g. highest versus lowest quartile of total protein intake as percentage of energy (Q4 versus Q1), HR = 1.12 (1.01, 1.25)]; mainly explained by higher animal protein intake and CVD mortality [Q4 versus Q1, CVD mortality: 1.28 (1.03, 1.60)]. The association of animal protein intake and CVD was mainly contributed to by protein from meat and dairy. Total plant protein intake was not associated with all-cause or cause-specific mortality, mainly explained by null associations for protein from grains and potatoes; but higher intake of protein from legumes, nuts, vegetables, and fruits was associated with lower risk of all-cause and cause-specific mortality. Findings for total and animal protein intake were corroborated in a meta-analysis of eleven prospective cohort studies including the Rotterdam Study (total 64,306 deaths among 350,452 participants): higher total protein intake was associated with higher all-cause mortality [pooled RR for highest versus lowest quantile 1.05 (1.01, 1.10)]; and for dose-response per 5 energy percent (E%) increment, 1.02 (1.004, 1.04); again mainly driven by an association between animal protein and CVD mortality [highest versus lowest, 1.09 (1.01, 1.18); per 5 E% increment, 1.05 (1.02, 1.09)]. Furthermore, in the meta-analysis a higher plant protein intake was associated with lower all-cause and CVD mortality [e.g. for all-cause mortality, highest versus lowest, 0.93 (0.87, 0.99); per 5 E% increment, 0.87 (0.78, 0.98), for CVD mortality, highest versus lowest 0.86 (0.73, 1.00)]. Evidence from prospective cohort studies to date suggests that total protein intake is positively associated with all-cause mortality, mainly driven by a harmful association of animal protein with CVD mortality. Plant protein intake is inversely associated with all-cause and CVD mortality. Our findings support current dietary recommendations to increase intake of plant protein in place of animal protein.Clinical trial registry number and website NTR6831, https://www.trialregister.nl/trial/6645.

Dietary saturated fat intake and risk of stroke: Systematic review and dose-response meta-analysis of prospective cohort studies

BACKGROUND AND AIMS

Because of the conflicting research results, the association between saturated fatty acid (SFA) consumption and the risk of stroke remains controversial. We conducted a meta-analysis to evaluate potential dose-response relation between SFA intake and stroke.

METHODS AND RESULTS

PubMed, Embase, the Cochrane Library Central Register of Controlled Trials, and Web of Science were searched. Summary relative risks (RRs) of the highest vs. the lowest category of SFA intake and their 95% confidence intervals (CIs) were pooled by random-effects models. Linear or nonlinear dose-response trend estimations were evaluated with data from categories of SFA consumption in each study. Fourteen studies involving a total of 598,435 participants were eligible for high vs. low meta-analysis, and 12 studies involving a total of 462,268 participants were eligible for the dose-response relation assessment. Higher dietary SFA intake was associated with a decreased overall risk for stroke (RR, 0.87; 95% CI, 0.78-0.96; I² = 37.8%). A linear relation between SFA and stroke was explored (P = 0.01), the pooled RR of stroke per 10 g/day increase in SFA intake was 0.94 (95% CI, 0.89-0.98; P = 0.01).

CONCLUSION

This meta-analysis further demonstrated that a higher consumption of dietary SFA is associated with a lower risk of stroke, and every 10 g/day increase in SFA intake is associated with a 6% relative risk reduction in the rate of stroke. Further research is needed to explore the influence of specific SFA types and different macronutrient replacement models of SFA on the stroke risk.

Dietary Cholesterol and Cardiovascular Risk: A Science Advisory From the American Heart Association

The elimination of specific dietary cholesterol target recommendations in recent guidelines has raised questions about its role with respect to cardiovascular disease. This advisory was developed after a review of human studies on the relationship of dietary cholesterol with blood lipids, lipoproteins, and cardiovascular disease risk to address questions about the relevance of dietary cholesterol guidance for heart health. Evidence from observational studies conducted in several countries generally does not indicate a significant association with cardiovascular disease risk. Although meta-analyses of intervention studies differ in their findings, most associate intakes of cholesterol that exceed current average levels with elevated total or low-density lipoprotein cholesterol concentrations. Dietary guidance should focus on healthy dietary patterns (eg, Mediterranean-style and DASH [Dietary Approaches to Stop Hypertension]–style diets) that are inherently relatively low in cholesterol with typical levels similar to the current US intake. These patterns emphasize fruits, vegetables, whole grains, low-fat or fat-free dairy products, lean protein sources, nuts, seeds, and liquid vegetable oils. A recommendation that gives a specific dietary cholesterol target within the context of food-based advice is challenging for clinicians and consumers to implement; hence, guidance focused on dietary patterns is more likely to improve diet quality and to promote cardiovascular health.

Threshold-Effect Association of Dietary Cholesterol Intake with Dyslipidemia in Chinese Adults: Results from the China Health and Nutrition Survey in 2015

The association of dietary cholesterol intake with dyslipidemia and subtypes is controversial. This study aimed to examine the association of dietary cholesterol intake with dyslipidemia and subtypes in Chinese adults. Using data from the China Health and Nutrition Survey (CHNS) in 2015, the present study selected 4383 participants aged 18–59 years who were free of diabetes, apoplexy, and myocardial infarction disease. Information was obtained on dietary intake, anthropometric measurements, and blood laboratory measurements. Dietary cholesterol intake was calculated based on the data collected by consecutive 3 days 24 h recalls combined with the weighing of household seasonings and categorized by 11 levels: The first 10 levels in ranges of 50 mg/day and the 11th level at ≥500 mg/day. Dyslipidemia, hypercholesterolemia, hypertriglyceridemia, low-density lipoprotein (LDL)-hypercholesterolemia, and high-density lipoprotein (HDL)-hypocholesterolemia were defined based on the Chinese adult dyslipidemia prevention guide (2016 edition). Multivariable logistic regressions were performed to examine the association of dietary cholesterol intake levels with dyslipidemia and subtypes. The prevalence of dyslipidemia was 37.5% among Chinese adults in 2015 (hypercholesterolemia 9.6%, HDL-hypocholesterolemia 21.1%, LDL-hypercholesterolemia 12.7%, and hypertriglyceridemia 15.2%). The lowest prevalence of hypercholesterolemia and LDL-hypercholesterolemia was 6.7% and 9.4%, respectively, which was relative to a dietary cholesterol intake level of 100.0 to <150.0 mg/day. After adjusting for all potential confounders, adults with the highest dietary cholesterol intake level of ≥500 mg/day compared with the dietary cholesterol intake of 100.0 to <150.0 mg/day showed one-time higher odds of hypercholesterolemia (odds ratios (OR) 2.0, 95% confidence intervals (CI) 1.3–3.3), as well as LDL-hypercholesterolemia (OR 2.0, 95% CI 1.3–3.0), but a null association of dietary cholesterol intake with dyslipidemia, hypertriglyceridemia, and HDL-hypocholesterolemia. The study suggested that a dietary cholesterol intake level of 500 mg/day and above may be a threshold point for high odds of hypercholesterolemia and LDL-hypercholesterolemia.

Risks of ischaemic heart disease and stroke in meat eaters, fish eaters, and vegetarians over 18 years of follow-up: results from the prospective EPIC-Oxford study

OBJECTIVE

To examine the associations of vegetarianism with risks of ischaemic heart disease and stroke.

DESIGN

Prospective cohort study.

SETTING

The EPIC-Oxford study, a cohort in the United Kingdom with a large proportion of non-meat eaters, recruited across the country between 1993 and 2001.

PARTICIPANTS

48 188 participants with no history of ischaemic heart disease, stroke, or angina (or cardiovascular disease) were classified into three distinct diet groups: meat eaters (participants who consumed meat, regardless of whether they consumed fish, dairy, or eggs; n=24 428), fish eaters (consumed fish but no meat; n=7506), and vegetarians including vegans (n=16 254), based on dietary information collected at baseline, and subsequently around 2010 (n=28 364).

MAIN OUTCOME MEASURES

Incident cases of ischaemic heart disease and stroke (including ischaemic and haemorrhagic types) identified through record linkage until 2016.

RESULTS

Over 18.1 years of follow-up, 2820 cases of ischaemic heart disease and 1072 cases of total stroke (519 ischaemic stroke and 300 haemorrhagic stroke) were recorded. After adjusting for sociodemographic and lifestyle confounders, fish eaters and vegetarians had 13% (hazard ratio 0.87, 95% confidence interval 0.77 to 0.99) and 22% (0.78, 0.70 to 0.87) lower rates of ischaemic heart disease than meat eaters, respectively (P<0.001 for heterogeneity). This difference was equivalent to 10 fewer cases of ischaemic heart disease (95% confidence interval 6.7 to 13.1 fewer) in vegetarians than in meat eaters per 1000 population over 10 years. The associations for ischaemic heart disease were partly attenuated after adjustment for self reported high blood cholesterol, high blood pressure, diabetes, and body mass index (hazard ratio 0.90, 95% confidence interval 0.81 to 1.00 in vegetarians with all adjustments). By contrast, vegetarians had 20% higher rates of total stroke (hazard ratio 1.20, 95% confidence interval 1.02 to 1.40) than meat eaters, equivalent to three more cases of total stroke (95% confidence interval 0.8 to 5.4 more) per 1000 population over 10 years, mostly due to a higher rate of haemorrhagic stroke. The associations for stroke did not attenuate after further adjustment of disease risk factors.

CONCLUSIONS

In this prospective cohort in the UK, fish eaters and vegetarians had lower rates of ischaemic heart disease than meat eaters, although vegetarians had higher rates of haemorrhagic and total stroke.

Patterns of plant and animal protein intake are strongly associated with cardiovascular mortality: the Adventist Health Study-2 cohort

Background

Current evidence suggests that plant and animal proteins are intimately associated with specific large nutrient clusters that may explain part of their complex relation with cardiovascular health. We aimed at evaluating the association between specific patterns of protein intake with cardiovascular mortality.

Methods

We selected 81 337 men and women from the Adventist Health Study-2. Diet was assessed between 2002 and 2007, by using a validated food frequency questionnaire. Dietary patterns based on the participants' protein consumption were derived by factor analysis. Cox regression analysis was used to estimate multivariate-adjusted hazard ratios (HRs) adjusted for sociodemographic and lifestyle factors and dietary components.

Results

There were 2276 cardiovascular deaths during a mean follow-up time of 9.4 years. The HRs for cardiovascular mortality were 1.61 [98.75% confidence interval (CI), 1.12 2.32; P-trend < 0.001] for the 'Meat' protein factor and 0.60 (98.75% CI, 0.42 0.86; P-trend < 0.001) for the 'Nuts & Seeds' protein factor (highest vs lowest quintile of factor scores). No significant associations were found for the 'Grains', 'Processed Foods' and 'Legumes, Fruits & Vegetables' protein factors. Additional adjustments for the participants' vegetarian dietary pattern and nutrients related to cardiovascular disease outcomes did not change the results.

Conclusions

Associations between the 'Meat' and 'Nuts & Seeds' protein factors and cardiovascular outcomes were strong and could not be ascribed to other associated nutrients considered to be important for cardiovascular health. Healthy diets can be advocated based on protein sources, preferring low contributions of protein from meat and higher intakes of plant protein from nuts and seeds.

Dietary total fat, fatty acids intake, and risk of cardiovascular disease: a dose-response meta-analysis of cohort studies

BACKGROUND

Several epidemiological studies have investigated the association between dietary fat intake and cardiovascular disease. However, dietary recommendations based on systematic review and meta-analysis might be more credible.

METHODS AND RESULTS

Pubmed, Embase and Cochrane library were searched up to July 1st 2018 for cohort studies reporting associations of dietary fat intake and risk of CVDs. By comparing the highest vs. the lowest categories of fat or fatty acids intake, we found that higher dietary trans fatty acids (TFA) intake was associated with increased risk of CVDs [RR:1.14(1.08-1.21)]. However, no association was observed between total fat, monounsaturated fatty acids (MUFA), saturated fatty acids (SFA), and polyunsaturated fatty acids (PUFA), and risk of CVDs. Subgroup analysis found a cardio-protective effect of PUFA in the studies that has been followed up more than 10 years [0.95(0.91-0.99), I2 = 62.4%]. Dose-response analysis suggested that the risk of CVDs increased 16% [1.16 (1.07-1.25), Plinearity = 0.033] for an increment of 2% energy/day of TFA intake.

CONCLUSIONS

This current meta-analysis of cohort studies suggested that total fat, SFA, MUFA, and PUFA intake were not associated with the risk of cardiovascular disease. However, we found that higher TFA intake is associated with greater risk of CVDs in a dose-response fashion. Furthermore, the subgroup analysis found a cardio-protective effect of PUFA in studies followed up for more than 10 years.

High-Carbohydrate Diets and Food Patterns and Their Associations with Metabolic Disease in the Korean Population

PURPOSE

Although an Asian diet is typically high in carbohydrate and low in fat, there has been a steady increase in the rate of cardiometabolic disease in Asian countries over the past decade. We evaluated food patterns of a high-carbohydrate diet and examined their associations with metabolic disease.

MATERIALS AND METHODS

Using data from the 2013-2015 Korean National Health and Nutrition Examination Survey, we included a total of 13106 subjects aged 20 years or older in this study. Diet was divided into seven groups according to the percentage of energy from carbohydrates. Food patterns were evaluated as individual servings per food group. Multivariate logistic regression was conducted to estimate odds ratios (OR) for metabolic disease.

RESULTS

The proportions of men and women exceeding the recommended range of carbohydrate intake were 58.0% and 60.0%, respectively. A higher carbohydrate diet was associated with intake of low energy and saturated fats, with more grains and fruit, but less meat, fish, egg, bean (MFEB), and dairy consumption. Carbohydrate intake decreased by 3.0-3.4% per serving of MFEB and milk. In men, the highest carbohydrate group showed an OR of 1.35 [95% confidence interval (CI), 0.91 to 1.99] for metabolic syndrome, although this failed to show statistical significance. In women, the highest carbohydrate group had an OR of 1.38 (95% CI, 1.06 to 1.80) for a reduced level of high-density lipoprotein cholesterol.

CONCLUSION

This study suggests that a very-high-carbohydrate diet for the Korean population is attributable to lower consumption of MFEB and dairy products and is associated with several metabolic risk factors. The appropriate distribution of macronutrients for the prevention and management of metabolic disease should be explored.

Dietary n-6 polyunsaturated fatty acids and cardiovascular disease: Epidemiologic evidence

Epidemiologists have been studying the effect of n-6 polyunsaturated fatty acids (PUFAs) intake on the risk of cardiovascular disease (CVD) for many decades. Abundant evidence from prospective studies on the clinical endpoints of CVD, including cohort studies measuring n-6 PUFA intake by food frequency questionnaires and nested case-control studies using biomarkers of intake level, strongly support that higher intakes of n-6 PUFAs are associated with a lower risk of CVD. Furthermore, a significant reduction in CVD risk can be achieved when saturated fatty acids (SFAs) is replaced by n-6 PUFAs. Evidence from appropriately designed and vigorously executed randomized controlled trials support that high-PUFA (predominantly linoleic acid) and low-SFA diets, compared to high-SFA diets, reduced the risk of coronary heart disease. Overall, epidemiologic studies provide a solid evidence base of the current dietary guidelines that recommend replacing SFA by PUFA, both n-6 and n-3 PUFA, for CVD prevention.

Dietary cholesterol intake and stroke risk: a meta-analysis

Background/Objectives

The association between dietary cholesterol and stroke risk has remained controversial over the past two decades. The aim of this meta-analysis was to assess the relationship between dietary cholesterol and stroke risk.

Results

Seven prospective studies including 269,777 non-overlapping individuals (4,604 strokes) were included. The combined RR of stroke for higher cholesterol intake (> 300 mg/day) was 0.98 (95% CI, 0.90–1.07), and the combined RR of stroke for higher cholesterol intake (> 300 mg/day) in females (age of ≥ 60 years or body mass index of ≥ 24 kg/m²) was 1.18 (95% CI, 1.02–1.36).

Materials and Methods

The PubMed, Medline, Embase, Web of Knowledge, and Google Scholar databases were searched. Relevant studies were identified by searching these online databases through September 2017. The relative risk (RR) and 95% confidence interval (CI) were used to investigate the strength of the association.

Conclusions

Higher cholesterol intake has no association with the overall stroke risk. Age and body mass index affect the relationship between dietary cholesterol intake and stroke risk. However, the association between higher dietary cholesterol and stroke risk in males remains unclear.

A Critical Review of the Consensus Statement from the European Atherosclerosis Society Consensus Panel 2017

BACKGROUND

The Consensus Statement from the European Atherosclerosis Society (EAS) Consensus Panel 2017 concludes on the basis of 3 different types of clinical studies that low-density lipoprotein (LDL) causes atherosclerotic cardiovascular disease (ASCVD). In Mendelian randomization studies, rare genetic mutations affecting LDL receptor function were found to cause higher or lower LDL-C levels, which are associated with correspondingly altered ASCVD risk. In prospective cohort studies and randomized controlled trials (RCTs) of statins, a remarkably consistent log-linear association was demonstrated between the absolute magnitude of LDL-C exposure and ASCVD risk. The EAS Statement proposes that any mechanism of lowering plasma LDL concentration should reduce the risk of ASCVD events proportional to the absolute reduction in LDL-C and the cumulative duration of exposure to lower LDL-C. However, as we explain, we do not find this conclusion acceptable.

SUMMARY

Our review points out that different interpretations are possible for the results of Mendelian randomization studies. As for prospective cohort studies, many inconsistent reports on the association of LDL-C and ASCVD were disregarded when drafting the Statement, reports with and without genetic factors related to LDL receptor function should be analyzed separately, and the term ASCVD in the Statement is used inappropriately because myocardial infarction and cerebral infarction differ in their association with LDL-C. As for RCTs, clinical reports on statins published before and after the implementation of new regulations affecting clinical trials (2004/2005) should not both be included in meta-analyses because the evaluated efficacy of statins changed markedly, and the irreversible adverse effects of statins need to be evaluated more rigorously now that their mechanisms have been elucidated. Key Messages: Apart from the EAS hypothesis that LDL causes ASCVD, recent pharmacological/biochemical studies, as summarized in this review and elsewhere, have revealed that atherosclerosis is caused by statins taken to lower LDL-C, as well as by warfarin and some types of vegetable fats and oils, in the absence of significantly elevated LDL-C levels. Thus, the promotion of statin treatment by the Statement is rather risky and we do not feel that the conclusions are justified for the prevention of ASCVD.

High Dietary Saturated Fat is Associated with a Low Risk of Intracerebral Hemorrhage and Ischemic Stroke in Japanese but not in Non-Japanese: A Review and Meta-Analysis of Prospective Cohort Studies

AIM

The associations between dietary saturated fatty acids and the risks of stroke subtypes in cohort studies were examined by a meta-analysis of separate ethnic Japanese and non-Japanese cohorts, and causes of their difference were elucidated.

METHOD

Log hazard ratio (HR) with 95% confidence interval (CI) of the highest versus the lowest saturated fat intake from cohort studies were weighed by an inverse variance method to combine HRs.

RESULTS

Five studies of intracerebral hemorrhage and 11 studies/comparisons of ischemic stroke were selected. A meta-analysis of intracerebral hemorrhage excluding subarachnoid hemorrhage showed a strong inverse association in Japanese (n=3, HR=0.55, 95% CI 0.32-0.94) but not in non-Japanese (n=2, HR=0.98, 95% CI 0.62-1.53). A meta-analysis of ischemic stroke showed a mild inverse association in Japanese (n=4, HR=0.82, 95% CI 0.71-0.93) but not in non-Japanese (n=7, HR= 0.93, 95% CI 0.84-1.03). The effect size of saturated fat in reducing the risk of stroke in Japanese was stronger for intracerebral hemorrhage (45% reduction) than for ischemic stroke (18% reduction).

CONCLUSIONS

In Japanese but not in non-Japanese, a diet high in saturated fat is associated with a low risk of intracerebral hemorrhage and ischemic stroke. This may be due to differences in the range of intake of saturated fat, genetic susceptibility, incidence of lacunar infarction, and/or confounding factors such as dietary proteins. An intervention study targeting Japanese will be required to verify the causality.

A summary of meat intakes and health burdens

This review summarizes published meta-analysis outcomes on the associations between meat intakes and burden of diseases. A novel assessment process was developed, combining selected Cochrane Review measures, AMSTAR checklist, and other quality measures identified by authors during preliminary phases of the review process. Meat intakes have been found to be statistically significant associated with 21 burden of diseases. A total of 37 risk-outcome best dose-response estimations were identified, all were positively associated, and 21 of them with low to moderate, or insignificant heterogeneity. The highest dose-responses per 50 g increases in processed meat intake at 95% confident levels were 1.81 (1.32, 2.48) for esophageal cancer, 1.71 (1.34, 2.19) for stomach cancer, 1.42 (1.07, 1.89) for CHD, 1.32 (1.19, 1.48) for diabetes, and 1.24 (1.13, 1.35) for colon cancer incidences, and 1.24 (1.09, 1.40) for CVD mortality. The highest dose-responses per each 65 g increases in total red meat intake were 1.36 (1.16, 1.58) for endometrial cancer, 1.25 (1.10, 1.41) esophageal cancer, and 1.22 (1.16, 1.23) for lung cancer incidences. In addition, 14 statistically significant associations in terms of high vs low meat intake relative risks were also identified. Total red meat intakes were found negatively associated with CVD and cancer mortalities, and poultry meat intakes were found negatively associated with all-cause and cancer mortalities, and rectal cancer incidences in low meat consumption Asian countries. Current global and dietary Comparative Risk Assessments may underestimate burden of diseases attributed to meat intakes. More investigation is needed in low-meat consumption countries.

Dietary Fat and Risk of Cardiovascular Disease: Recent Controversies and Advances

Health effects of dietary fats have been extensively studied for decades. However, controversies exist on the effects of various types of fatty acids, especially saturated fatty acid (SFA), on cardiovascular disease (CVD). Current evidence supports that different types of dietary fatty acids have divergent effects on CVD risk, and the effects also depend strongly on the comparison or replacement macronutrient. A significant reduction in CVD risk can be achieved if SFAs are replaced by unsaturated fats, especially polyunsaturated fatty acids. Intake of industrially produced trans fat is consistently associated with higher CVD risk. Both n-6 and n-3 polyunsaturated fatty acids are associated with lower CVD risk, although the effects of fish oil supplementation remains inconsistent. The 2015-2020 Dietary Guidelines for Americans place greater emphasis on types of dietary fat than total amount of dietary fat and recommend replacing SFAs with unsaturated fats, especially polyunsaturated fatty acids for CVD prevention.

Dietary Protein Intake and Stroke Risk in a General Japanese Population: The Hisayama Study

BACKGROUND AND PURPOSE

The influence of dietary protein intake on stroke risk is an area of interest. We investigated the association between dietary protein intake and stroke risk in Japanese, considering sources of protein.

METHODS

A total of 2400 subjects aged 40 to 79 years were followed up for 19 years. Dietary protein intake was estimated using a 70-item semiquantitative food frequency questionnaire. The risk estimates for incident stroke and its subtypes were calculated using a Cox proportional hazards model.

RESULTS

During the follow-up, 254 participants experienced stroke events; of these, 172 had ischemic stroke, and 58 had intracerebral hemorrhage. Higher total protein intake was significantly associated with lower risks of stroke and intracerebral hemorrhage (both P for trend <0.05). With regard to sources of protein, the risks of total stroke and ischemic stroke significantly decreased by 40% (95% confidence interval, 12%-59%) and 40% (5%-62%), respectively, in subjects with the highest quartile of vegetable protein intake compared with those with the lowest one. In contrast, subjects with the highest quartile of animal protein intake had a 53% (4%-77%) lower risk of intracerebral hemorrhage. Vegetable protein intake was positively correlated with intakes of soybean products, vegetable, and algae, whereas animal protein intake was positively correlated with intakes of fish, meat, eggs, and milk/dairy products. Both types of protein intakes were negatively correlated with intakes of rice and alcohol.

CONCLUSIONS

Our findings suggest that higher dietary protein intake is associated with a reduced risk of stroke in the general Japanese population.

Animal Proteins as Important Contributors to a Healthy Human Diet

Adequate protein intake is critical for health and development. Generally, protein of animal origin is of higher quality for humans owing to its amino acid pattern and good digestibility. When administered in mixtures it can enhance the quality of plant proteins, but its availability is often low in low-income communities, especially in young children, the elderly, and pregnant and lactating women, who have increased requirements and in whom high-quality protein also stimulates (bone) growth and maintenance. Although high protein intake was associated with increased type 2 diabetes mellitus risk, milk and seafood are good sources of branched chain amino acids and taurine, which act beneficially on glucose metabolism and blood pressure. However, high consumption of protein-rich animal food is also associated with adverse health effects and higher risk for noncommunicable diseases, partly related to other components of these foods, like saturated fatty acids and potential carcinogens in processed meat but also the atherogenic methionine metabolite homocysteine. In moderation, however, animal proteins are especially important for health maintenance in vulnerable persons.

Association Between Protein Intake and Mortality in Hypertensive Patients Without Chronic Kidney Disease in the OLD-HTA Cohort

Protein intake may have some benefits on reducing blood pressure and cardiovascular events, but their effects are still debated. The objective of this study was to test the prognostic value of protein intake assessed by 24-hour urinary urea in a cohort of hypertensive patients with preserved renal function. A total of 1128 hypertensive patients were followed according to tertile of protein intake adjusted for ideal body weight: <0.70, 0.70 to 0.93, and >0.93 g/kg. Baseline characteristics (mean±standard deviation) were age 45.1±13.2 years, systolic/diastolic blood pressure 185±32/107±20 mm Hg, and estimated glomerular filtration rate 82±32 mL/min. After 10 years of follow-up, 289 deaths occurred, 202 of which were of cardiovascular cause. After adjustment for major cardiovascular risk factors, patients in the second and third tertiles of protein intake had a decreased risk of all-cause death (hazard ratio [95% confidence interval], 0.71 [0.56-0.91]) and cardiovascular death (0.72 [0.54-0.96]), but not of stroke death (0.72 [0.41-1.28]) in comparison to patients in the low protein intake tertile. Normal-high protein intake was associated with a better outcome in a subset of the population: younger patients, low salt intake, without aortic atherosclerosis, or previous cardiovascular events (Pinteraction<0.10 for all). Hypertensive patients having a protein intake >0.7 g/kg ideal body weight, particularly those at low risk, had lower all-cause and cardiovascular mortality rates. Physicians may encourage hyper tensive patients to have normal or high protein diet in addition to low salt consumption, moderate alcohol consumption, and regular physical activity.

Evidence-Based Guideline of the German Nutrition Society: Fat Intake and Prevention of Selected Nutrition-Related Diseases

As nutrition-related chronic diseases have become more and more frequent, the importance of dietary prevention has also increased. Dietary fat plays a major role in human nutrition, and modification of fat and/or fatty acid intake could have a preventive potential. The aim of the guideline of the German Nutrition Society (DGE) was to systematically evaluate the evidence for the prevention of the widespread diseases obesity, type 2 diabetes mellitus, dyslipoproteinaemia, hypertension, metabolic syndrome, coronary heart disease (CHD), stroke, and cancer through the intake of fat or fatty acids. The main results can be summarized as follows: it was concluded with convincing evidence that a reduced intake of total and saturated fat as well as a larger intake of polyunsaturated fatty acids (PUFA) at the expense of saturated fatty acids (SFA) reduces the concentration of total and low-density lipoprotein cholesterol in plasma. Furthermore, there is convincing evidence that a high intake of trans fatty acids increases risk of dyslipoproteinaemia and that a high intake of long-chain polyunsaturated n-3 fatty acids reduces the triglyceride concentration in plasma. A high fat intake increases the risk of obesity with probable evidence when total energy intake is not controlled for (ad libitum diet). When energy intake is controlled for, there is probable evidence for no association between fat intake and risk of obesity. A larger intake of PUFA at the expense of SFA reduces risk of CHD with probable evidence. Furthermore, there is probable evidence that a high intake of long-chain polyunsaturated n-3 fatty acids reduces risk of hypertension and CHD. With probable evidence, a high trans fatty acid intake increases risk of CHD. The practical consequences for current dietary recommendations are described at the end of this article.

Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies

OBJECTIVE

To systematically review associations between intake of saturated fat and trans unsaturated fat and all cause mortality, cardiovascular disease (CVD) and associated mortality, coronary heart disease (CHD) and associated mortality, ischemic stroke, and type 2 diabetes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, Cochrane Central Registry of Controlled Trials, Evidence-Based Medicine Reviews, and CINAHL from inception to 1 May 2015, supplemented by bibliographies of retrieved articles and previous reviews.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Observational studies reporting associations of saturated fat and/or trans unsaturated fat (total, industrially manufactured, or from ruminant animals) with all cause mortality, CHD/CVD mortality, total CHD, ischemic stroke, or type 2 diabetes.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted data and assessed study risks of bias. Multivariable relative risks were pooled. Heterogeneity was assessed and quantified. Potential publication bias was assessed and subgroup analyses were undertaken. The GRADE approach was used to evaluate quality of evidence and certainty of conclusions.

RESULTS

For saturated fat, three to 12 prospective cohort studies for each association were pooled (five to 17 comparisons with 90,501-339,090 participants). Saturated fat intake was not associated with all cause mortality (relative risk 0.99, 95% confidence interval 0.91 to 1.09), CVD mortality (0.97, 0.84 to 1.12), total CHD (1.06, 0.95 to 1.17), ischemic stroke (1.02, 0.90 to 1.15), or type 2 diabetes (0.95, 0.88 to 1.03). There was no convincing lack of association between saturated fat and CHD mortality (1.15, 0.97 to 1.36; P=0.10). For trans fats, one to six prospective cohort studies for each association were pooled (two to seven comparisons with 12,942-230,135 participants). Total trans fat intake was associated with all cause mortality (1.34, 1.16 to 1.56), CHD mortality (1.28, 1.09 to 1.50), and total CHD (1.21, 1.10 to 1.33) but not ischemic stroke (1.07, 0.88 to 1.28) or type 2 diabetes (1.10, 0.95 to 1.27). Industrial, but not ruminant, trans fats were associated with CHD mortality (1.18 (1.04 to 1.33) v 1.01 (0.71 to 1.43)) and CHD (1.42 (1.05 to 1.92) v 0.93 (0.73 to 1.18)). Ruminant trans-palmitoleic acid was inversely associated with type 2 diabetes (0.58, 0.46 to 0.74). The certainty of associations between saturated fat and all outcomes was "very low." The certainty of associations of trans fat with CHD outcomes was "moderate" and "very low" to "low" for other associations.

CONCLUSIONS

Saturated fats are not associated with all cause mortality, CVD, CHD, ischemic stroke, or type 2 diabetes, but the evidence is heterogeneous with methodological limitations. Trans fats are associated with all cause mortality, total CHD, and CHD mortality, probably because of higher levels of intake of industrial trans fats than ruminant trans fats. Dietary guidelines must carefully consider the health effects of recommendations for alternative macronutrients to replace trans fats and saturated fats.

Dietary cholesterol and cardiovascular disease: a systematic review and meta-analysis

BACKGROUND

Dietary cholesterol has been suggested to increase the risk of cardiovascular disease (CVD), which has led to US recommendations to reduce cholesterol intake.

OBJECTIVE

The authors examine the effects of dietary cholesterol on CVD risk in healthy adults by using systematic review and meta-analysis.

DESIGN

MEDLINE, Cochrane Central, and Commonwealth Agricultural Bureau Abstracts databases were searched through December 2013 for prospective studies that quantified dietary cholesterol. Investigators independently screened citations and verified extracted data on study and participant characteristics, outcomes, and quality. Random-effect models meta-analysis was used when at least 3 studies reported the same CVD outcome.

RESULTS

Forty studies (17 cohorts in 19 publications with 361,923 subjects and 19 trials in 21 publications with 632 subjects) published between 1979 and 2013 were eligible for review. Dietary cholesterol was not statistically significantly associated with any coronary artery disease (4 cohorts; no summary RR), ischemic stroke (4 cohorts; summary RR: 1.13; 95% CI: 0.99, 1.28), or hemorrhagic stroke (3 cohorts; summary RR: 1.09; 95% CI: 0.79, 1.50). Dietary cholesterol statistically significantly increased both serum total cholesterol (17 trials; net change: 11.2 mg/dL; 95% CI: 6.4, 15.9) and low-density lipoprotein (LDL) cholesterol (14 trials; net change: 6.7 mg/dL; 95% CI: 1.7, 11.7 mg/dL). Increases in LDL cholesterol were no longer statistically significant when intervention doses exceeded 900 mg/d. Dietary cholesterol also statistically significantly increased serum high-density lipoprotein cholesterol (13 trials; net change: 3.2 mg/dL; 95% CI: 0.9, 9.7 mg/dL) and the LDL to high-density lipoprotein ratio (5 trials; net change: 0.2; 95% CI: 0.0, 0.3). Dietary cholesterol did not statistically significantly change serum triglycerides or very-low-density lipoprotein concentrations.

CONCLUSION

Reviewed studies were heterogeneous and lacked the methodologic rigor to draw any conclusions regarding the effects of dietary cholesterol on CVD risk. Carefully adjusted and well-conducted cohort studies would be useful to identify the relative effects of dietary cholesterol on CVD risk.

NADPH Oxidase Activity in Cerebral Arterioles Is a Key Mediator of Cerebral Small Vessel Disease-Implications for Prevention

Cerebral small vessel disease (SVD), a common feature of brain aging, is characterized by lacunar infarcts, microbleeds, leukoaraiosis, and a leaky blood-brain barrier. Functionally, it is associated with cognitive decline, dementia, depression, gait abnormalities, and increased risk for stroke. Cerebral arterioles in this syndrome tend to hypertrophy and lose their capacity for adaptive vasodilation. Rodent studies strongly suggest that activation of Nox2-dependent NADPH oxidase activity is a crucial driver of these structural and functional derangements of cerebral arterioles, in part owing to impairment of endothelial nitric oxide synthase (eNOS) activity. This oxidative stress may also contribute to the breakdown of the blood-brain barrier seen in SVD. Hypertension, aging, metabolic syndrome, smoking, hyperglycemia, and elevated homocysteine may promote activation of NADPH oxidase in cerebral arterioles. Inhibition of NADPH oxidase with phycocyanobilin from spirulina, as well as high-dose statin therapy, may have potential for prevention and control of SVD, and high-potassium diets merit study in this regard. Measures which support effective eNOS activity in other ways-exercise training, supplemental citrulline, certain dietary flavonoids (as in cocoa and green tea), and capsaicin, may also improve the function of cerebral arterioles. Asian epidemiology suggests that increased protein intakes may decrease risk for SVD; conceivably, arginine and/or cysteine-which boosts tissue glutathione synthesis, and can be administered as N-acetylcysteine-mediate this benefit. Ameliorating the risk factors for SVD-including hypertension, metabolic syndrome, hyperglycemia, smoking, and elevated homocysteine-also may help to prevent and control this syndrome, although few clinical trials have addressed this issue to date.

Dietary intakes of glutamic acid and glycine are associated with stroke mortality in Japanese adults

BACKGROUND

Dietary intakes of glutamic acid and glycine have been reported to be associated with blood pressure. However, the link between intakes of these amino acids and stroke has not been studied.

OBJECTIVE

We aimed to examine the association between glutamic acid and glycine intakes and the risk of mortality from stroke in a population-based cohort study in Japan.

METHODS

The analyses included 29,079 residents (13,355 men and 15,724 women) of Takayama City, Japan, who were aged 35-101 y and enrolled in 1992. Their body mass index ranged from 9.9 to 57.4 kg/m(2). Their diets were assessed by a validated food frequency questionnaire. Deaths from stroke were ascertained over 16 y.

RESULTS

During follow-up, 677 deaths from stroke (328 men and 349 women) were identified. A high intake of glutamic acid in terms of a percentage of total protein was significantly associated with a decreased risk of mortality from total stroke in women after controlling for covariates; the HR (95% CI) for the highest vs. lowest quartile was 0.72 (0.53, 0.98; P-trend: 0.03). Glycine intake was significantly associated with an increased risk of mortality from total and ischemic stroke in men without history of hypertension at baseline; the HRs (95% CIs) for the highest vs. lowest tertile were 1.60 (0.97, 2.51; P-trend: 0.03) and 1.88 (1.01, 3.52; P-trend: 0.02), respectively. There was no association between animal or vegetable protein intake and mortality from total and any subtype of stroke.

CONCLUSION

The data suggest that glutamic acid and glycine intakes may be associated with risk of stroke mortality. Given that this is an initial observation, our results need to be confirmed.

Saturated fat intake and cardiovascular disease in Japanese population

The evidence for the impact of saturated fat intake on cardiovascular disease remains inconsistent. One reason for this inconsistency may be the large difference in the distribution of saturated fat intake between the East and West. In this review, we focus on the published literature on this topic among Japanese population. Three studies have examined the link between saturated fat intake and intraparenchymal hemorrhage, consistently showing an inverse association. However, the association for ischemic stroke is less clear, although it is generally inverse. As for myocardial infarction, the findings in Japanese studies are inconsistent, as are those of Western studies. The JPHC study, however, found a positive association, the first report in Asia. Taken together with the results of the JPHC and Western studies, a saturated fat intake of around 20 g/day (approximately 10% of total energy) may be optimal, which corresponds to 200 g of milk a day and 150 g of meat every other day.

The case for diet: a safe and efficacious strategy for secondary stroke prevention

Diet is strongly associated with risk for first stroke. In particular, observational and experimental research suggests that a Mediterranean-type diet may reduce risk for first ischemic stroke with an effect size comparable to statin therapy. These data for first ischemic stroke suggest that diet may also be associated with risk for recurrent stroke and that diet modification might represent an effective intervention for secondary prevention. However, research on dietary pattern after stroke is limited and direct experimental evidence for a therapeutic effect in secondary prevention does not exist. The uncertain state of science in this area is reflected in recent guidelines on secondary stroke prevention from the American Heart Association, in which the Mediterranean-type diet is listed with only a class IIa recommendation (level of evidence C). To change guidelines and practice, research is needed, starting with efforts to better define current nutritional practices of stroke patients. Food frequency questionnaires and mobile applications for real-time recording of intake are available for this purpose. Dietary strategies for secondary stroke prevention are low risk, high potential, and warrant further evaluation.

Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

Low-carbohydrate diets and cardiovascular and total mortality in Japanese: a 29-year follow-up of NIPPON DATA80

Long-term safety of consuming low-carbohydrate diets (LCD) in Asian populations, whose carbohydrate intake is relatively high, is not known. In the present study, the association of LCD with CVD and total mortality was assessed using data obtained in the NIPPON DATA80 (National Integrated Project for Prospective Observation of Non-communicable Disease and Its Trends in the Aged 1980) during 29 years of follow-up. At baseline in 1980, data were collected from study participants aged ≥ 30 years from randomly selected areas in Japan. LCD scores were calculated based on the percentage of energy as carbohydrate, fat and protein, estimated by 3 d weighed food records. A total of 9200 participants (56% women, mean age 51 years) were followed up. During the follow-up, 1171 CVD deaths (52% in women) and 3443 total deaths (48% in women) occurred. The multivariable-adjusted hazard ratio (HR) for CVD mortality using the Cox model comparing the highest v. lowest deciles of LCD score was 0·60 (95% CI 0·38, 0·94; P(trend) = 0·021) for women and 0·78 (95% CI 0·58, 1·05; P(trend) = 0·079) for women and men combined; the HR for total mortality was 0·74 (95% CI 0·57, 0·95; P(trend) = 0·029) for women and 0·87 (95% CI 0·74, 1·02; P(trend) = 0·090) for women and men combined. None of the associations was statistically significant in men. No differential effects of animal-based and plant-fish-based LCD were observed. In conclusions, moderate diets lower in carbohydrate and higher in protein and fat are significantly inversely associated with CVD and total mortality in women.

Monounsaturated fatty acids, olive oil and health status: a systematic review and meta-analysis of cohort studies

Background

The aim of the present meta-analysis of cohort studies was to focus on monounsaturated fat (MUFA) and cardiovascular disease, cardiovascular mortality as well as all-cause mortality, and to distinguish between the different dietary sources of MUFA.

Methods

Literature search was performed using the electronic databases PUBMED, and EMBASE until June 2nd, 2014. Study specific risk ratios and hazard ratios were pooled using a inverse variance random effect model.

Results

Thirty-two cohort studies (42 reports) including 841,211 subjects met the objectives and were included. The comparison of the top versus bottom third of the distribution of a combination of MUFA (of both plant and animal origin), olive oil, oleic acid, and MUFA:SFA ratio in each study resulted in a significant risk reduction for: all-cause mortality (RR: 0.89, 95% CI 0.83, 0.96, p = 0.001; I² = 64%), cardiovascular mortality (RR: 0.88, 95% CI 0.80, 0.96, p = 0.004; I² = 50%), cardiovascular events (RR: 0.91, 95% CI 0.86, 0.96, p = 0.001; I² = 58%), and stroke (RR: 0.83, 95% CI 0.71, 0.97, p = 0.02; I² = 70%). Following subgroup analyses, significant associations could only be found between higher intakes of olive oil and reduced risk of all-cause mortality, cardiovascular events, and stroke, respectively. The MUFA subgroup analyses did not reveal any significant risk reduction.

Conclusion

The results indicate an overall risk reduction of all-cause mortality (11%), cardiovascular mortality (12%), cardiovascular events (9%), and stroke (17%) when comparing the top versus bottom third of MUFA, olive oil, oleic acid, and MUFA:SFA ratio. MUFA of mixed animal and vegetable sources per se did not yield any significant effects on these outcome parameters. However, only olive oil seems to be associated with reduced risk. Further research is necessary to evaluate specific sources of MUFA (i.e. plant vs. animal) and cardiovascular risk.

Electronic supplementary material

The online version of this article (doi:10.1186/1476-511X-13-154) contains supplementary material, which is available to authorized users.

Plasma fatty acid composition and incident ischemic stroke in middle-aged adults: the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

The association of individual fatty acids with ischemic stroke has not been thoroughly studied, and results have been inconsistent. Few prospective studies have systematically explored the association of biomarkers of fatty acid intake with stroke. The aim of this study was to explore which individual plasma fatty acids would be associated with higher risk of ischemic stroke among whites.

METHODS

We studied 3,870 white men and women from the Minneapolis field center of the Atherosclerosis Risk in Communities (ARIC) Study, aged 45-64 years at baseline (1987-1989), who had plasma cholesterol ester (CE) and phospholipid (PL) fatty acids measured. Participants were followed through 2008 for incident ischemic stroke. Hazard ratios (HRs) with 95% confidence intervals (CIs) across quartiles of each fatty acid, measured as the percentage of total fatty acids, were calculated using the Cox proportional hazards model.

RESULTS

During a maximum of 22 years of follow-up, we identified 168 cases of ischemic stroke. After adjustment for age and sex, plasma levels of saturated fatty acids were associated positively: HR (95% CI) of the highest versus the lowest quartile for CE fraction was 1.93 (1.23-3.04, p for trend = 0.01) and that for PL fraction was 1.64 (1.05-2.57, p for trend = 0.03). There was also a positive linear association with monounsaturated fatty acids, especially with palmitoleic acid: HR (95% CI) of the highest versus the lowest quartile for CE fraction was 1.86 (1.20-2.87, p for trend = 0.003) and that for PL fraction was 1.52 (0.99-2.34, p for trend = 0.005). No associations of ω-3 and ω-6 polyunsaturated fatty acids with ischemic stroke were observed, but linoleic acid was inversely and nonlinearly associated with ischemic stroke: HR (95% CI) of the highest versus the lowest quartile for CE fraction was 0.64 (0.43-0.97, p for trend = 0.13) and that for PL fraction was 0.69 (0.45-1.05, p for trend = 0.24). These associations were generally unchanged after adjustment for cardiovascular risk factors.

CONCLUSIONS

In this US cohort of whites, we found significant positive associations of plasma saturated and monounsaturated fatty acids, especially of palmitoleic acid, with ischemic stroke. We also found an inverse nonlinear association between linoleic acid and ischemic stroke.

Serum fatty acids and incidence of ischemic stroke among postmenopausal women

BACKGROUND AND PURPOSE

Although studies have linked types of fatty acids with coronary heart disease, data on individual fatty acids and risk of ischemic stroke are limited. We aimed to examine the associations between serum fatty acid concentrations and incidence of ischemic stroke and its subtypes.

METHODS

We conducted a prospective case-control study nested in the Women's Health Initiative Observational Study cohort of postmenopausal US women aged 50 to 79 years. Between 1993 and 2003, incident cases of ischemic stroke were matched 1:1 to controls on age, race, and length of follow-up (964 matched pairs). Conditional logistic regression was used to estimate odds ratios and 99.9% confidence intervals (CI) for ischemic stroke and its subtypes.

RESULTS

The multivariable-adjusted odds ratios and 99.9% CI of ischemic stroke associated with a 1-SD increment in serum fatty acid concentration were 1.38 (99.9% CI, 1.05-1.83) for linoelaidic acid (18:2tt, SD=0.04%), 1.27 (99.9% CI, 1.06-1.51) for palmitic acid (16:0, SD=2.74%), 1.20 (99.9% CI, 1.01-1.43) for oleic acid (18:1n9, SD=2.32%), 0.72 (99.9% CI, 0.59-0.87) for docosapentaenoic acid (22:5n3, SD=0.18%), 0.72 (99.9% CI, 0.59-0.87) for docosahexaenoic acid (22:6n3, SD=0.91%), and 0.81 (99.9% CI, 0.67-0.98) for arachidonic acid (20:4n6, SD=2.02%). These associations were generally consistent for atherothrombotic and lacunar stroke but not cardioembolic stroke.

CONCLUSIONS

These findings suggest that individual serum trans, saturated, and monounsaturated fatty acids are positively associated with particular ischemic stroke subtypes, whereas individual n3 and n6 polyunsaturated fatty acids are inversely associated.