Diet to Stop Hypertension: Should Fats be Included?

PURPOSE OF REVIEW: International guidelines emphasize advice to incorporate dietary measures for the prevention and in the management of hypertension. Current data show that modest reductions in weight can have an impact on blood pressure. Reducing salt and marine oils have also shown consistent benefit in reducing blood pressure. Whether other dietary constituents, in particular the amount and type of fat that play important roles in cardiovascular prevention, influence blood pressure sufficiently to be included in the management of hypertension is less certain. In this review, we provide a summary of the most recent findings, with a focus on dietary patterns, fats and other nutrients and their impact on blood pressure and hypertension. RECENT FINDINGS: Since reducing salt consumption is an established recommendation only corollary dietary advice is subject to the current review. Population studies that have included reliable evaluation of fat intake have indicated almost consistently blood pressure lowering with consumption of marine oils and fats. Results with vegetable oils are inconclusive. However dietary patterns that included total fat reduction and changes in the nature of vegetable fats/oils have suggested beneficial effects on blood pressure. Plant-based foods, dairy foods and yoghurt particularly, may also lower blood pressure irrespective of fat content. Total fat consumption is not directly associated with blood pressure except when it is part of a weight loss diet. Consumption of marine oils has mostly shown moderate blood pressure lowering and possibly greatest effect with docosahexaenoic acid-rich oil.

Australian Atherosclerosis Society Position Statement on Lipoprotein(a): Clinical and Implementation Recommendations.

This position statement provides guidance to cardiologists and related specialists on the management of adult patients with elevated lipoprotein(a) [Lp(a)]. Elevated Lp(a) is an independent and causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve disease (CAVD). While circulating Lp(a) levels are largely determined by ancestry, they are also influenced by ethnicity, hormones, renal function, and acute inflammatory events, such that measurement should be done after accounting for these factors. Further, circulating Lp(a) concentrations should be estimated using an apo(a)-isoform independent assay that employs appropriate calibrators and reports the results in molar units (nmol/L). Selective screening strategies of high-risk patients are recommended, but universal screening of the population is currently not advised. Testing for elevated Lp(a) is recommended in all patients with premature ASCVD and those considered to be at intermediate-to-high risk of ASCVD. Elevated Lp(a) should be employed to assess and stratify risk and to enable a decision on initiation or intensification of preventative treatments, such as cholesterol lowering therapy. In adult patients with elevated Lp(a) at intermediate-to-high risk of ASCVD, absolute risk should be reduced by addressing all modifiable behavioural, lifestyle, psychosocial and clinical risk factors, including maximising cholesterol-lowering with statin and ezetimibe and, where appropriate, PCSK9 inhibitors. Apheresis should be considered in patients with progressive ASCVD. New ribonucleic acid (RNA)-based therapies which directly lower Lp(a) are undergoing clinical trials.

Dietary patterns, dietary nutrients and cardiovascular disease.

A healthy dietary pattern can benefit multiple cardiovascular disease (CVD) risk factors. In conjunction with current standard-of-care pharmaceutical interventions it can provide an effective strategy for the prevention of CVD. Previous dietary recommendations have focused on targeting macronutrients. However, most of the recent international dietary guidelines now recommend a whole food, dietary pattern approach, whilst avoiding quantitative nutrient advice. The guidelines recommend: (1) increased intake of plant-based foods including complex, fibre-rich carbohydrates such as wholegrains, fruits and vegetables, but restricting the intake of refined starches; (2) substituting saturated fats with polyunsaturated and monounsaturated oils; (3) reducing salt intake; (4) increased fish consumption (or fish oils where applicable); (5) reducing sugar-sweetened drinks and added sugars; (6) avoiding butter and cream particularly in individuals at increased risk of CVD, but encouraging fermented products such as yoghurt; there is no specific advice on cheese and milk; (7) allowing consumption of lean meat in moderation but restricting processed meats; and (8) reducing cholesterol intake and foods rich in cholesterol (e.g., eggs and crustaceans) for those with diabetes and at increased CVD risk. The dietary guidelines should be adhered to in conjunction with low-to-moderate alcohol consumption, regular physical activity, avoiding tobacco and maintaining a healthy weight. This review summarises recently published research, international guidelines and position statements for minimizing CVD risk.

Dairy Foods: Is Its Cardiovascular Risk Profile Changing?

PURPOSE OF REVIEW: The majority of international guidelines for cardiovascular disease (CVD) prevention recommend moderate intake of low fat or fat-free products, and limiting full fat dairy food because of its high saturated fatty acid content. Recent equivocal observational studies and greater understanding of the complex nature of dairy foods has led to reappraisal for some types of dairy foods. RECENT FINDINGS: Current guidelines from major cardiovascular societies have differed; interpretation of major observational studies has been inconsistent. Apart from the adverse effect of butter, consumption of more complex dairy products notably fermented varieties, yogurt in particular, appears to be inversely associated with outcomes of CVD and type 2 diabetes (T2D). Reduced fat in dairy food appears advantageous but is no longer a unanimous view although is preferred for people at increased CVD risk and dyslipidemia. Changed evidence has led to new advice regarding consumption of some dairy foods. The apparent beneficial effects of cheese, fermented milk, and yogurt allow for increased consumption of nutritious staple foods. Reduced fat yogurt may be desirable as part of diets for individuals with CVD or T2D.

Shark liver oil supplementation enriches endogenous plasmalogens and reduces markers of dyslipidemia and inflammation.

Plasmalogens are membrane glycerophospholipids with diverse biological functions. Reduced plasmalogen levels have been observed in metabolic diseases; hence, increasing their levels might be beneficial in ameliorating these conditions. Shark liver oil (SLO) is a rich source of alkylglycerols that can be metabolized into plasmalogens. This study was designed to evaluate the impact of SLO supplementation on endogenous plasmalogen levels in individuals with features of metabolic disease. In this randomized, double-blind, placebo-controlled cross-over study, the participants (10 overweight or obese males) received 4-g Alkyrol® (purified SLO) or placebo (methylcellulose) per day for 3 weeks followed by a 3-week washout phase and were then crossed over to 3 weeks of the alternate placebo/Alkyrol® treatment. SLO supplementation led to significant changes in plasma and circulatory white blood cell lipidomes, notably increased levels of plasmalogens and other ether lipids. In addition, SLO supplementation significantly decreased the plasma levels of total free cholesterol, triglycerides, and C-reactive protein. These findings suggest that SLO supplementation can enrich plasma and cellular plasmalogens and this enrichment may provide protection against obesity-related dyslipidemia and inflammation.

Development and validation of a ceramide- and phospholipid-based cardiovascular risk estimation score for coronary artery disease patients.

AIMS: Distinct ceramide lipids have been shown to predict the risk for cardiovascular disease (CVD) events, especially cardiovascular death. As phospholipids have also been linked with CVD risk, we investigated whether the combination of ceramides with phosphatidylcholines (PCs) would be synergistic in the prediction of CVD events in patients with atherosclerotic coronary heart disease in three independent cohort studies. METHODS AND RESULTS: Ceramides and PCs were analysed using liquid chromatography-mass spectrometry (LC-MS) in three studies: WECAC (The Western Norway Coronary Angiography Cohort) (N = 3789), LIPID (Long-Term Intervention with Pravastatin in Ischaemic Disease) trial (N = 5991), and KAROLA (Langzeiterfolge der KARdiOLogischen Anschlussheilbehandlung) (N = 1023). A simple risk score, based on the ceramides and PCs showing the best prognostic features, was developed in the WECAC study and validated in the two other cohorts. This score was highly significant in predicting CVD mortality [multiadjusted hazard ratios (HRs; 95% confidence interval) per standard deviation were 1.44 (1.28-1.63) in WECAC, 1.47 (1.34-1.61) in the LIPID trial, and 1.69 (1.31-2.17) in KAROLA]. In addition, a combination of the risk score with high-sensitivity troponin T increased the HRs to 1.63 (1.44-1.85) and 2.04 (1.57-2.64) in WECAC and KAROLA cohorts, respectively. The C-statistics in WECAC for the risk score combined with sex and age was 0.76 for CVD death. The ceramide-phospholipid risk score showed comparable and synergistic predictive performance with previously published CVD risk models for secondary prevention. CONCLUSION: A simple ceramide- and phospholipid-based risk score can efficiently predict residual CVD event risk in patients with coronary artery disease.

Practical Guidance for Food Consumption to Prevent Cardiovascular Disease.

This dietary guidance, informed by best contemporary evidence, aims to assist medical practitioners and allied health professionals in advising patients for the primary and secondary prevention of cardiovascular disease (CVD). While differing in some details from other current guidelines, the core messages accord with those published in 2019 by the American College of Cardiology/American Heart Association and the European Society of Cardiology/European Atherosclerosis Society; the National Lipid Association in 2014 and the NH&MRC Australian Dietary Guidelines in 2013. These were assessed through the Appraisal of Guidelines for Research and Evaluation (AGREE II) and the levels of evidence and classes of a recommendation developed using the GRADE system. Recommendations with high levels of evidence include increased consumption of plant based foods comprising mainly complex, fibre enriched carbohydrates (wholegrains, fruits and vegetables) while limiting intake of refined starches; partial replacement of saturated fats with monounsaturated or polyunsaturated fats and oils; reduced salt intake; achievement and maintenance of healthy weight; and low-to-moderate consumption of alcohol. Additional guidance but with moderate levels of evidence includes increased consumption of fish (and fish oils where indicated); reduction in sugar-sweetened beverages and added sugars; avoidance of butter and cream especially in those at increased CVD risk but encouragement of yoghurt; allow moderate consumption of lean meat but limit intake of processed meats; and limit cholesterol-rich foods such as eggs and crustaceans for those at increased CVD risk. Guidance has been formulated qualitatively on food categories of commonly eaten foods while avoiding prescriptive quantitative measures that are less readily translatable. This approach accords with current guidelines such as the American College of Cardiology/American Heart Association 2019 guidelines and is understandable and readily implemented.

Gaps in the Care of Familial Hypercholesterolaemia in Australia: First Report From the National Registry.

BACKGROUND: Familial hypercholesterolaemia (FH) is under-diagnosed and under-treated worldwide, including Australia. National registries play a key role in identifying patients with FH, understanding gaps in care and advancing the science of FH to improve care for these patients. METHODS: The FH Australasia Network has established a national web-based registry to raise awareness of the condition, facilitate service planning and inform best practice and care services in Australia. We conducted a cross-sectional analysis of 1,528 FH adults enrolled in the registry from 28 lipid clinics. RESULTS: The mean age at enrolment was 53.4±15.1 years, 50.5% were male and 54.3% had undergone FH genetic testing, of which 61.8% had a pathogenic FH-causing gene variant. Only 14.0% of the cohort were family members identified through cascade testing. Coronary artery disease (CAD) was reported in 28.0% of patients (age of onset 49.0±10.5 years) and 64.9% had at least one modifiable cardiovascular risk factor. The mean untreated LDL-cholesterol was 7.4±2.5 mmol/L. 80.8% of patients were on lipid-lowering therapy with a mean treated LDL-cholesterol of 3.3±1.7 mmol/L. Among patients receiving lipid-lowering therapies, 25.6% achieved an LDL-cholesterol target of <2.5 mmol/L without CAD or <1.8 mmol/L with CAD. CONCLUSION: Patients in the national FH registry are detected later in life, have a high burden of CAD and risk factors, and do not achieve guideline-recommended LDL-cholesterol targets. Genetic and cascade testing are under-utilised. These deficiencies in care need to be addressed as a public health priority.

Changing dietary approaches to prevent cardiovascular disease.

PURPOSE OF REVIEW: We have focused on recent research relevant to effects of dietary patterns and major food groups on cardiovascular outcomes, taking into account guidelines and position statements from expert authorities, with an emphasis on important changes in recommendations, some of which remain controversial. RECENT FINDINGS: Major findings include: refocusing on qualitative patterns of food consumption replacing quantitative prescriptive advice on nutrients; increasing intake of plant foods; substituting saturated fats with polyunsaturated and monounsaturated oils; reducing salt intake; regular consumption of fish with a focus on omega-3 enrichment; not restricting dairy foods, other than butter and cream, with encouragement of some fermented products; reducing cholesterol intake for those at increased cardiovascular risk and diabetes, allowing 7-eggs weekly; restricting processed meats and allowing moderate lean meat consumption; preference for fiber-rich complex carbohydrates and reduced sugar intake; maintaining healthy bodyweight; and although water is the preferred beverage, allowing moderate alcohol consumption to national guidelines and avoiding alcohol in specific cardiovascular disorders. SUMMARY: The new approach that focuses on healthier patterns of food intake is more readily understood by health practitioners and translatable to consumers and patients.

Cholesterol transport between red blood cells and lipoproteins contributes to cholesterol metabolism in blood.

Lipoproteins play a key role in transport of cholesterol to and from tissues. Recent studies have also demonstrated that red blood cells (RBCs), which carry large quantities of free cholesterol in their membrane, play an important role in reverse cholesterol transport. However, the exact role of RBCs in systemic cholesterol metabolism is poorly understood. RBCs were incubated with autologous plasma or isolated lipoproteins resulting in a significant net amount of cholesterol moved from RBCs to HDL, while cholesterol from LDL moved in the opposite direction. Furthermore, the bi-directional cholesterol transport between RBCs and plasma lipoproteins was saturable and temperature-, energy-, and time-dependent, consistent with an active process. We did not find LDLR, ABCG1, or scavenger receptor class B type 1 in RBCs but found a substantial amount of ABCA1 mRNA and protein. However, specific cholesterol efflux from RBCs to isolated apoA-I was negligible, and ABCA1 silencing with siRNA or inhibition with vanadate and Probucol did not inhibit the efflux to apoA-I, HDL, or plasma. Cholesterol efflux from and cholesterol uptake by RBCs from Abca1+/+ and Abca1-/- mice were similar, arguing against the role of ABCA1 in cholesterol flux between RBCs and lipoproteins. Bioinformatics analysis identified ABCA7, ABCG5, lipoprotein lipase, and mitochondrial translocator protein as possible candidates that may mediate the cholesterol flux. Together, these results suggest that RBCs actively participate in cholesterol transport in the blood, but the role of cholesterol transporters in RBCs remains uncertain.