Effects of Initiating Moderate Alcohol Intake on Cardiometabolic Risk in Adults With Type 2 Diabetes: A 2-Year Randomized, Controlled Trial

Dietary Polyphenols, Mediterranean Diet, Prediabetes, and Type 2 Diabetes: A Narrative Review of the Evidence

Dietary polyphenols come mainly from plant-based foods including fruits, vegetables, whole grains, coffee, tea, and nuts. Polyphenols may influence glycemia and type 2 diabetes (T2D) through different mechanisms, such as promoting the uptake of glucose in tissues, and therefore improving insulin sensitivity. This review aims to summarize the evidence from clinical trials and observational prospective studies linking dietary polyphenols to prediabetes and T2D, with a focus on polyphenol-rich foods characteristic of the Mediterranean diet. We aimed to describe the metabolic biomarkers related to polyphenol intake and genotype-polyphenol interactions modulating the effects on T2D. Intakes of polyphenols, especially flavan-3-ols, and their food sources have demonstrated beneficial effects on insulin resistance and other cardiometabolic risk factors. Several prospective studies have shown inverse associations between polyphenol intake and T2D. The Mediterranean diet and its key components, olive oil, nuts, and red wine, have been inversely associated with insulin resistance and T2D. To some extent, these associations may be attributed to the high amount of polyphenols and bioactive compounds in typical foods conforming this traditional dietary pattern. Few studies have suggested that genetic predisposition can modulate the relationship between polyphenols and T2D risk. In conclusion, the intake of polyphenols may be beneficial for both insulin resistance and T2D risk.

Environmental/lifestyle factors in the pathogenesis and prevention of type 2 diabetes

BACKGROUND

Environmental and lifestyle changes, in addition to the ageing of populations, are generally believed to account for the rapid global increase in type 2 diabetes prevalence and incidence in recent decades.

DISCUSSION

In this review, we present a comprehensive overview of factors contributing to diabetes risk, including aspects of diet quality and quantity, little physical activity, increased monitor viewing time or sitting in general, exposure to noise or fine dust, short or disturbed sleep, smoking, stress and depression, and a low socioeconomic status. In general, these factors promote an increase in body mass index. Since loss of β-cell function is the ultimate cause of developing overt type 2 diabetes, environmental and lifestyle changes must have resulted in a higher risk of β-cell damage in those at genetic risk. Multiple mechanistic pathways may come into play.

CONCLUSIONS

Strategies of diabetes prevention should aim at promoting a 'diabetes-protective lifestyle' whilst simultaneously enhancing the resistance of the human organism to pro-diabetic environmental and lifestyle factors. More research on diabetes-protective mechanisms seems warranted.

Environmental/lifestyle factors in the pathogenesis and prevention of type 2 diabetes

BACKGROUND

Environmental and lifestyle changes, in addition to the ageing of populations, are generally believed to account for the rapid global increase in type 2 diabetes prevalence and incidence in recent decades.

DISCUSSION

In this review, we present a comprehensive overview of factors contributing to diabetes risk, including aspects of diet quality and quantity, little physical activity, increased monitor viewing time or sitting in general, exposure to noise or fine dust, short or disturbed sleep, smoking, stress and depression, and a low socioeconomic status. In general, these factors promote an increase in body mass index. Since loss of β-cell function is the ultimate cause of developing overt type 2 diabetes, environmental and lifestyle changes must have resulted in a higher risk of β-cell damage in those at genetic risk. Multiple mechanistic pathways may come into play.

CONCLUSIONS

Strategies of diabetes prevention should aim at promoting a 'diabetes-protective lifestyle' whilst simultaneously enhancing the resistance of the human organism to pro-diabetic environmental and lifestyle factors. More research on diabetes-protective mechanisms seems warranted.

Lessons and Challenges from a 6-Month Randomized Pilot Study of Daily Ethanol Consumption: Research Methodology and Study Design

Background: Observational studies and crossover feeding studies suggest that moderate alcohol use may benefit cardiovascular risk, but we know of no long-term randomized trials that have tested this hypothesis. Objective: We evaluated the feasibility of an efficacy study of daily ethanol use in a 6-mo randomized pilot study in adults at higher cardiovascular risk. Methods: In a double-blind, randomized, controlled parallel-design trial, we screened 67 adults aged ≥55 y and randomly assigned 45 participants to consume 150 mL of an artificially sweetened beverage with or without 10% grain alcohol daily for 6 mo. Participants were asked to consume no other alcohol and returned monthly to receive the beverage and undergo measurement of HDL cholesterol, liver function tests, and complete blood counts. Results: Of the 45 randomly assigned participants, 39 completed the trial; the primary reason cited for attrition was inconvenience. None of the participants reported problem drinking or developed any serious adverse events or abnormal biochemical findings. However, we observed no differences in concentrations of HDL cholesterol, HDL lipoprotein subclasses, aspartate aminotransferase, alanine aminotransferase, γ-glutamyltransferase, mean corpuscular volume, or adiponectin between the alcohol and control arms, suggesting that adherence was poor. Every participant accurately identified their assigned beverage, most with great certainty. Conclusions: In this parallel-design pilot study of daily alcohol use, we observed none of the expected changes in markers of alcohol intake, which suggests poor adherence to this pure alcohol intervention. Our results suggest that long-term trials of alcohol consumption, if they are conducted in light drinkers similar to these, must use pragmatic designs for maximal feasibility. This study was registered at clinicaltrials.gov as NCT01377727.

Dietary Strategies and Novel Pharmaceutical Approaches Targeting Serum ApoA-I Metabolism: A Systematic Overview

The incidence of CHD is still increasing, which underscores the need for new preventive and therapeutic approaches to decrease CHD risk. In this respect, increasing apoA-I concentrations may be a promising approach, especially through increasing apoA-I synthesis. This review first provides insight into current knowledge on apoA-I production, clearance, and degradation, followed by a systematic review of dietary and novel pharmacological approaches to target apoA-I metabolism. For this, a systematic search was performed to identify randomized controlled intervention studies that examined effects of whole foods and (non)nutrients on apoA-I metabolism. In addition, novel pharmacological approaches were searched for, which were specifically developed to target apoA-I metabolism. We conclude that both dietary components and pharmacological approaches can be used to increase apoA-I concentrations or functionality. For the dietary components in particular, more knowledge about the underlying mechanisms is necessary, as increasing apoA-I per se does not necessarily translate into a reduced CHD risk.

Lifestyle recommendations for the prevention and management of metabolic syndrome: an international panel recommendation

The importance of metabolic syndrome (MetS) lies in its associated risk of cardiovascular disease and type 2 diabetes, as well as other harmful conditions such as nonalcoholic fatty liver disease. In this report, the available scientific evidence on the associations between lifestyle changes and MetS and its components is reviewed to derive recommendations for MetS prevention and management. Weight loss through an energy-restricted diet together with increased energy expenditure through physical activity contribute to the prevention and treatment of MetS. A Mediterranean-type diet, with or without energy restriction, is an effective treatment component. This dietary pattern should be built upon an increased intake of unsaturated fat, primarily from olive oil, and emphasize the consumption of legumes, cereals (whole grains), fruits, vegetables, nuts, fish, and low-fat dairy products, as well as moderate consumption of alcohol. Other dietary patterns (Dietary Approaches to Stop Hypertension, new Nordic, and vegetarian diets) have also been proposed as alternatives for preventing MetS. Quitting smoking and reducing intake of sugar-sweetened beverages and meat and meat products are mandatory. Nevertheless, there are inconsistencies and gaps in the evidence, and additional research is needed to define the most appropriate therapies for MetS. In conclusion, a healthy lifestyle is critical to prevent or delay the onset of MetS in susceptible individuals and to prevent cardiovascular disease and type 2 diabetes in those with existing MetS. The recommendations provided in this article should help patients and clinicians understand and implement the most effective approaches for lifestyle change to prevent MetS and improve cardiometabolic health.

Short- and medium-term effects of light to moderate alcohol intake on glycaemic control in diabetes mellitus: a systematic review and meta-analysis of randomized trials

BACKGROUND

People with diabetes are told that drinking alcohol may increase their risk of hypoglycaemia.

AIMS

To report the effects of alcohol consumption on glycaemic control in people with diabetes mellitus.

METHODS

Medline, EMBASE and the Cochrane Library databases were searched in 2015 to identify randomized trials that compared alcohol consumption with no alcohol use, reporting glycaemic control in people with diabetes. Data on blood glucose, HbA_1c and numbers of hypoglycaemic episodes were pooled using random effects meta-analysis.

RESULTS

Pooled data from nine short-term studies showed no difference in blood glucose concentrations between those who drank alcohol in doses of 16-80 g (median 20 g, 2.5 units) compared with those who did not drink alcohol at 0.5, 2, 4 and 24 h after alcohol consumption. Pooled data from five medium-term studies showed that there was no difference in blood glucose or HbA_1c concentrations at the end of the study between those who drank 11-18 g alcohol/day (median 13 g/day, 1.5 units/day) for 4-104 weeks and those who did not. We found no evidence of a difference in number of hypoglycaemic episodes or in withdrawal rates between randomized groups.

CONCLUSIONS

Studies to date have not provided evidence that drinking light to moderate amounts of alcohol, with or without a meal, affects any measure of glycaemic control in people with Type 2 diabetes. These results suggest that current advice that people with diabetes do not need to refrain from drinking moderate quantities of alcohol does not need to be changed; risks to those with Type 1 diabetes remain uncertain.

Serum bilirubin concentrations and incident coronary heart disease risk among patients with type 2 diabetes: the Dongfeng-Tongji cohort

AIMS

Elevated serum bilirubin levels are associated with decreased coronary heart disease (CHD) risk in cross-sectional studies among diabetic patients, but prospective evidence is limited. We investigated the relationship of serum bilirubin levels with incident CHD risk among type 2 diabetes patients.

METHODS

In a prospective study of 2918 type 2 diabetes embedded in the Dongfeng-Tongji cohort, serum total bilirubin (TBil), direct bilirubin (DBil), and indirect bilirubin (IBil) were measured at baseline. Cox proportional hazards models were used to examine the association between serum bilirubin levels and CHD risk.

RESULTS

A total of 440 CHD cases were identified during 12,017 person-years of follow-up. Compared with extreme quartiles, the adjusted hazard ratio and 95% confidence interval of incident CHD were 0.74 (0.56-0.99) with P trend = 0.08 in IBil, while in TBil and DBil, the bilirubin-CHD associations were not significant. Moreover, serum TBil and IBil levels were interacted with drinking status on the risk of incident CHD (P interaction = 0.021 and 0.037, respectively), and the associations were evident in ever drinkers. In drinkers, when serum TBil or IBil concentrations increased 1 μmol/L, the CHD risk both decreased 6% (95% CIs 0.89-0.99 and 0.87-1.00, respectively).

CONCLUSIONS

Serum IBil levels were marginally related to decreased incident CHD risk among type 2 diabetes. Drinking could potentially enhance the associations of serum TBil and DBil levels with incident CHD risk.

The effect of a reduction in alcohol consumption on blood pressure: a systematic review and meta-analysis

BACKGROUND

Although it is well established that heavy alcohol consumption increases the risk of hypertension, little is known about the effect of a reduction of alcohol intake on blood pressure. We aimed to assess the effect of a reduction in alcohol consumption on change in blood pressure stratified by initial amount of alcohol consumption and sex in adults.

METHODS

In this systematic review and meta-analysis, we searched MedLine, Embase, CENTRAL, and ClinicalTrials.gov from database inception up to July 13, 2016, for trials investigating the effect of a change of alcohol consumption on blood pressure in adults using keywords and MeSH terms related to alcohol consumption, blood pressure, and clinical trials, with no language restrictions. We also searched reference lists of identified articles and published meta-analyses and reviews. We included full-text articles with original human trial data for the effect of a change of alcohol consumption on blood pressure in adults, which reported a quantifiable change in average alcohol consumption that lasted at least 7 days and a corresponding change in blood pressure. We extracted data from published reports. We did random-effects meta-analyses stratified by amount of alcohol intake at baseline. All meta-analyses were done with Stata (version 14.1). For the UK, we modelled the effect of a reduction of alcohol consumption for 50% of the population drinking more than two standard drinks per day (ie, 12 g pure alcohol per drink).

FINDINGS

36 trials with 2865 participants (2464 men and 401 women) were included. In people who drank two or fewer drinks per day, a reduction in alcohol was not associated with a significant reduction in blood pressure; however, in people who drank more than two drinks per day, a reduction in alcohol intake was associated with increased blood pressure reduction. Reduction in systolic blood pressure (mean difference -5·50 mm Hg, 95% CI -6·70 to -4·30) and diastolic blood pressure (-3·97, -4·70 to -3·25) was strongest in participants who drank six or more drinks per day if they reduced their intake by about 50%. For the UK, the results would translate into more than 7000 inpatient hospitalisations and 678 cardiovascular deaths prevented every year.

INTERPRETATION

Reducing alcohol intake lowers blood pressure in a dose-dependent manner with an apparent threshold effect. Implementation of effective alcohol interventions in people who drink more than two drinks per day would reduce the disease burden from both alcohol consumption and hypertension, and should be prioritised in countries with substantial alcohol-attributable risk.

FUNDING

National Institute on Alcohol Abuse and Alcoholism of the National Institutes of Health (NIH).

Low-to-Moderate Alcohol Consumption is Associated With Hippocampal Volume in Fibromyalgia and Insomnia

Fibromyalgia and chronic insomnia are frequently comorbid conditions with heightened sensitivity to painful stimuli, potentially subserved by the hippocampus. Recent evidence suggests moderate alcohol consumption is associated with reduced fibromyalgia symptom severity. We examined the relationship among alcohol use, hippocampal morphology, fibromyalgia, and insomnia symptom severity in 41 fibromyalgia patients (19 with insomnia). A 14-day diary of sleep, pain, and alcohol consumption was followed by structural MRI. Analyses indicated greater bilateral hippocampal volume, lower clinical pain intensity, and better sleep quality in moderate drinkers versus abstainers. Underlying mechanisms may include gamma-amino butyric acid (GABA) receptor agonism, n-methyl d-aspartate (NMDA) receptor antagonism, and psychosocial factors. Further study of the relationship between alcohol use and fibromyalgia and insomnia symptom severity is warranted.

Nutrition Interventions for Cardiovascular Disease

Nutrition therapy is effective at controlling cardiovascular disease risk factors and therefore reducing cardiovascular disease risk. Physicians should play an active role in providing nutrition interventions for patients who would benefit from cardiovascular disease risk reduction or refer them to other professionals as needed. The evidence on nutrition interventions for blood pressure and lipid control, including overall dietary patterns, dietary fat and macronutrients, dietary cholesterol, sodium, and alcohol intake, is discussed.

Moderate Alcohol Consumption and Chronic Disease: The Case for a Long-Term Trial

Drinking within recommended limits is highly prevalent in much of the world, and strong epidemiological associations exist between moderate alcohol consumption and risk of several major chronic diseases, including coronary heart disease, diabetes, and breast cancer. In many cases, plausible biological mediators for these associations have been identified in randomized trials, but gold standard evidence that moderate drinking causes or prevents any chronic disease remains elusive and important concerns about available evidence have been raised. Although long-term randomized trials to test the observed associations have been termed impossible, clinical investigators have now successfully completed randomized trials of complex nutritional interventions in a variety of settings, along with trials of alcohol consumption itself of up to 2 years duration. The successful completion of these trials suggests that objections to the execution of a full-scale, long-term clinical trial of moderate drinking on chronic disease are increasingly untenable. We present potential lessons learned for such a trial and discuss key features to maximize its feasibility and value.

Nutrition in Type 2 Diabetes and the Metabolic Syndrome

For individuals at risk for type 2 diabetes mellitus or the metabolic syndrome, adherence to an idealized dietary pattern can drastically alter the risk and course of these chronic conditions. Target levels of carbohydrate intake should approximate 30% of consumed calories. Healthy food choices should include copious fruits, vegetables, and nuts while minimizing foods with high glycemic indices, especially processed foods.

Effects of initiating moderate wine intake on abdominal adipose tissue in adults with type 2 diabetes: a 2-year randomized controlled trial

Objective

To generate evidence-based conclusions about the effect of wine consumption on weight gain and abdominal fat accumulation and distribution in patients with type 2 diabetes.

Design

In the 2-year randomized controlled CASCADE (CArdiovaSCulAr Diabetes & Ethanol) trial, patients following a Mediterranean diet were randomly assigned to drink 150 ml of mineral water, white wine or red wine with dinner for 2 years. Visceral adiposity and abdominal fat distribution were measured in a subgroup of sixty-five participants, using abdominal MRI.

Setting

Ben-Gurion University of the Negev, Soroka-Medical Center and the Nuclear Research Center Negev, Israel.

Subjects

Alcohol-abstaining adults with well-controlled type 2 diabetes.

Results

Forty-eight participants (red wine, n 27; mineral water, n 21) who completed a second MRI measurement were included in the 2-year analysis. Similar weight losses (sd) were observed: red wine 1·3 (3·9) kg; water 1·0 (4·2) kg (P=0·8 between groups). Changes (95 % CI) in abdominal adipose-tissue distribution were similar: red wine, visceral adipose tissue (VAT) −3·0 (−8·0, 2·0) %, deep subcutaneous adipose tissue (DSAT) +5·2 (−1·1, 11·6) %, superficial subcutaneous adipose tissue (SSAT) −1·9 (−5·0, 1·2) %; water, VAT −3·2 (−8·9, 2·5) %, DSAT +2·9 (−2·8, 8·6) %, SSAT −0·15 (−3·3, 2·9) %. No changes in antidiabetic medication and no substantial changes in energy intake (+126 (sd 2889) kJ/d (+30·2 (sd 690) kcal/d), P=0·8) were recorded. A 2-year decrease in glycated Hb (β=0·28, P=0·05) was associated with a decrease in VAT.

Conclusions

Moderate wine consumption, as part of a Mediterranean diet, in persons with controlled diabetes did not promote weight gain or abdominal adiposity.

Metabolic profiling of alcohol consumption in 9778 young adults

Background: High alcohol consumption is a major cause of morbidity, yet alcohol is associated with both favourable and adverse effects on cardiometabolic risk markers. We aimed to characterize the associations of usual alcohol consumption with a comprehensive systemic metabolite profile in young adults.

Methods: Cross-sectional associations of alcohol intake with 86 metabolic measures were assessed for 9778 individuals from three population-based cohorts from Finland (age 24–45 years, 52% women). Metabolic changes associated with change in alcohol intake during 6-year follow-up were further examined for 1466 individuals. Alcohol intake was assessed by questionnaires. Circulating lipids, fatty acids and metabolites were quantified by high-throughput nuclear magnetic resonance metabolomics and biochemical assays.

Results: Increased alcohol intake was associated with cardiometabolic risk markers across multiple metabolic pathways, including higher lipid concentrations in HDL subclasses and smaller LDL particle size, increased proportions of monounsaturated fatty acids and decreased proportion of omega-6 fatty acids, lower concentrations of glutamine and citrate (P < 0.001 for 56 metabolic measures). Many metabolic biomarkers displayed U-shaped associations with alcohol consumption. Results were coherent for men and women, consistent across the three cohorts and similar if adjusting for body mass index, smoking and physical activity. The metabolic changes accompanying change in alcohol intake during follow-up resembled the cross-sectional association pattern (R²= 0.83, slope = 0.72 ± 0.04).

Conclusions: Alcohol consumption is associated with a complex metabolic signature, including aberrations in multiple biomarkers for elevated cardiometabolic risk. The metabolic signature tracks with long-term changes in alcohol consumption. These results elucidate the double-edged effects of alcohol on cardiovascular risk.

Alcohol use among adults in Uganda: findings from the countrywide non-communicable diseases risk factor cross-sectional survey

Background

There are limited data on levels of alcohol use in most sub-Saharan African countries.

Objective

We analyzed data from Uganda's non-communicable diseases risk factor survey conducted in 2014, to identify alcohol use prevalence and associated factors.

Design

The survey used the World Health Organization STEPS tool to collect data, including the history of alcohol use. Alcohol users were categorized into low-, medium-, and high-end users. Participants were also classified as having an alcohol-use-related disorder if, over the past 12 months, they were unable to stop drinking alcohol once they had started drinking, and/or failed to do what was normally expected of them because of drinking alcohol, and/or needed an alcoholic drink first in the morning to get going after a heavy drinking session the night before. Weighted logistic regression analysis was used to identify factors associated with medium- to high-end alcohol use.

Results

Of the 3,956 participants, 1,062 (26.8%) were current alcohol users, including 314 (7.9%) low-end, 246 (6.2%) medium-end, and 502 (12.7%) high-end users. A total of 386 (9.8%) were classified as having an alcohol-use-related disorder. Male participants were more likely to be medium- to high-end alcohol users compared to females; adjusted odds ratio (AOR)=2.34 [95% confidence interval (CI)=1.88–2.91]. Compared to residents in eastern Uganda, participants in central and western Uganda were more likely to be medium- to high-end users; AOR=1.47 (95% CI=1.01–2.12) and AOR=1.89 (95% CI=1.31–2.72), respectively. Participants aged 30–49 years and those aged 50–69 years were more likely to be medium- to high-end alcohol users, compared to those aged 18–29 years, AOR=1.49 (95% CI=1.16–1.91) and AOR=2.08 (95% CI=1.52–2.84), respectively.

Conclusions

The level of alcohol use among adults in Uganda is high, and 9.8% of the adult population has an alcohol-use-related disorder.

Molecular Properties of Red Wine Compounds and Cardiometabolic Benefits

Wine has been used since the dawn of human civilization. Despite many health benefits, there is still a lot of discussion about the real properties of its components and its actions on cells and molecular interactions. A large part of these issues permeate the fine line between the amount of alcohol that causes problems to organic systems and the amount that could be beneficial for the health. However, even after the process of fermentation, wine conserves different organic compounds from grapes, such as polysaccharides, acids, and phenolic compounds, such as flavonoids and nonflavonoids. These substances have known anti-inflammatory and antioxidant capacities, and are considered as regulatory agents in cardiometabolic process. In this study, the main chemical components present in the wine, its interaction with molecules and biological mechanisms, and their interference with intra- and extracellular signaling are reviewed. Finally, the properties of wine that may benefit cardiovascular system are also revised.

Managing dyslipidaemia in type 2 diabetes mellitus

Glucose-control has a modest beneficial effect on cardiovascular outcomes in patients with type 2 diabetes mellitus. Thus, managing other atherogenic risk factors including hypertriglyceridemia, low HDL-cholesterol and moderately elevated LDL-cholesterol levels with increased small dense LDL-cholesterol fraction, is crucial. Insulin resistance is a key pathophysiologic factor in this population. Treatment starts with lifestyle modifications, but current best programmes have not translated into positive cardiovascular outcomes. Lowering LDL-cholesterol with statins is currently the main treatment strategy, but significant residual risk remains. Attempts to elevate HDL-cholesterol and to reduce triglycerides levels, with niacin or fibrates have not improved cardiovascular prognosis, but addition of ezetimibe, or fibrates in specific patients subgroups, have shown modest benefit. Some glucose-lowering medications and bariatric surgery may also improve diabetic dyslipidemia. Results of three major cardiovascular outcome trials evaluating the effect of lowering LDL-cholesterol with PCSK9 inhibitors in large cohorts that include thousands of diabetic patients are pending.

Alcoholic Beverage Consumption and Chronic Diseases

Epidemiological and experimental studies have consistently linked alcoholic beverage consumption with the development of several chronic disorders, such as cancer, cardiovascular diseases, diabetes mellitus and obesity. The impact of drinking is usually dose-dependent, and light to moderate drinking tends to lower risks of certain diseases, while heavy drinking tends to increase the risks. Besides, other factors such as drinking frequency, genetic susceptibility, smoking, diet, and hormone status can modify the association. The amount of ethanol in alcoholic beverages is the determining factor in most cases, and beverage types could also make an influence. This review summarizes recent studies on alcoholic beverage consumption and several chronic diseases, trying to assess the effects of different drinking patterns, beverage types, interaction with other risk factors, and provide mechanistic explanations.

Resveratrol and Cardiovascular Diseases

The increased incidence of cardiovascular diseases (CVDs) has stimulated research for substances that could improve cardiovascular health. Among them, resveratrol (RES), a polyphenolic compound notably present in grapes and red wine, has been involved in the “French paradox”. RES is known for its antioxidant and anti-inflammatory properties and for its ability to upregulate endothelial NO synthase (eNOS). RES was able to scavenge ^•OH/O₂^•− and peroxyl radicals, which can limit the lipid peroxidation processes. Moreover, in bovine aortic endothelial cells (BAEC) under glucose-induced oxidative stress, RES restored the activity of dimethylargininedimethylaminohydrolase (DDAH), an enzyme that degrades an endogenous inhibitor of eNOS named asymmetric dimethylarginine (ADMA). Thus, RES could improve ^•NO availability and decrease the endothelial dysfunction observed in diabetes. Preclinical studies have made it possible to identify molecular targets (SIRT-1, AMPK, Nrf2, NFκB…); however, there are limited human clinical trials, and difficulties in the interpretation of results arise from the use of high-dose RES supplements in research studies, whereas low RES concentrations are present in red wine. The discussions on potential beneficial effects of RES in CVDs (atherosclerosis, hypertension, stroke, myocardial infarction, heart failure) should compare the results of preclinical studies with those of clinical trials.

How blockchain-timestamped protocols could improve the trustworthiness of medical science

Trust in scientific research is diminished by evidence that data are being manipulated. Outcome switching, data dredging and selective publication are some of the problems that undermine the integrity of published research. Here we report a proof-of-concept study  using a 'blockchain' as a low cost, independently verifiable method that could be widely and readily used to audit and confirm the reliability of scientific studies.

How blockchain-timestamped protocols could improve the trustworthiness of medical science

Trust in scientific research is diminished by evidence that data are being manipulated. Outcome switching, data dredging and selective publication are some of the problems that undermine the integrity of published research. Methods for using blockchain to provide proof of pre-specified endpoints in clinical trial protocols were first reported by Carlisle. We wished to empirically test such an approach using a clinical trial protocol where outcome switching has previously been reported. Here we confirm the use of blockchain as a low cost, independently verifiable method to audit and confirm the reliability of scientific studies.

How blockchain-timestamped protocols could improve the trustworthiness of medical science

Trust in scientific research is diminished by evidence that data are being manipulated. Outcome switching, data dredging and selective publication are some of the problems that undermine the integrity of published research. Methods for using blockchain to provide proof of pre-specified endpoints in clinical trial protocols were first reported by Carlisle. We wished to empirically test such an approach using a clinical trial protocol where outcome switching has previously been reported. Here we confirm the use of blockchain as a low cost, independently verifiable method to audit and confirm the reliability of scientific studies.

[Fundamental Properties of Aldehyde Dehydrogenase 2 (ALDH2) and the Importance of the ALDH2 Polymorphism]

Human aldehyde dehydrogenase 2 (ALDH2) is a 56 kDa mitochondrial protein that forms homodimers through hydrogen bonding interactions between the Glu487 and Arg475 residues of two ALDH2 proteins. Two ALDH2 homodimers can interact to form an ALDH2 tetramer. ALDH2 is widely distributed throughout the organs of the body. In addition to its dehydrogenase activity, ALDH2 also exhibits esterase and reductase activities, with the main substrates for these three activities being aldehydes, 4-nitrophenyl acetate and nitroglycerin, respectively. ALDH2 can be readily inhibited by a wide variety of endogenous and exogenous chemicals, but the induction or activation of this enzyme remains unlikely. The polymorphism of ALDH2 to the corresponding ALDH2*2 variant results in a severe deficiency in ALDH2 activity, and this particular polymorphism is prevalent among people of Mongoloid descent. It seems reasonable to expect that people with the ALDH2*2 variant would be more vulnerable to stress and diseases because ALDH2 defends the human body against toxic aldehydes. However, it has been suggested that people with the ALDH2*2 variant are protected by alternative stress-defending systems. The ALDH2*2 variant has been reported to be associated with many different kinds of diseases, although the mechanisms underlying these associations have not yet been elucidated. ALDH2 polymorphism has a significant impact on human health; further studies are therefore required to determine the practical implications of this polymorphism in the fields of preventive and clinical medicine.

Drinking pattern of wine and effects on human health: why should we drink moderately and with meals?

Epidemiological studies examining the effects of alcoholic beverages on human health may be unclear if they do not take into account drinking pattern parameters such as beverage type, regular moderateversusbinge drinking and drinking with meals.

Intake of Total Polyphenols and Some Classes of Polyphenols Is Inversely Associated with Diabetes in Elderly People at High Cardiovascular Disease Risk

BACKGROUND

Higher consumption of some polyphenols has been associated with a reduced risk of diabetes. However, no studies have evaluated the relation between all polyphenol subclasses and the incidence of diabetes.

OBJECTIVE

We aimed to prospectively examine the associations between the intake of total polyphenols and different groups of polyphenols (flavonoids, phenolic acids, stilbenes, lignans, and others) on the risk of incident diabetes in the PREDIMED (Prevención con Dieta Mediterránea) trial.

METHODS

This was an observational cohort analysis of the nondiabetic participants in the PREDIMED trial. This study was a multicenter, controlled, randomized, parallel-group feeding trial to assess the effects of either a Mediterranean diet that was supplemented with extra-virgin olive oil or nuts or advice to adhere to a low-fat control diet on cardiovascular outcomes in elderly men and women at high cardiovascular disease risk. From the 7447 randomly assigned participants, 3430 were selected because they were free of diabetes at baseline and filled out the food-frequency questionnaires (FFQs). Polyphenol intake was calculated by matching food consumption data from repeated FFQs with the Phenol-Explorer database on the polyphenol content of each reported food. HRs and 95% CIs for diabetes according to tertiles of polyphenol intake were estimated with the use of time-dependent Cox proportional hazards models.

RESULTS

Over a mean of 5.51 y of follow-up (18,900 person-years), there were 314 new cases of diabetes. After multivariable adjustment, we observed a 28% reduction in new-onset diabetes in the highest compared with the lowest tertile of total polyphenol intake (HR: 0.72; 95% CI: 0.52, 0.99; P-trend = 0.05). The intake of subclasses of polyphenols also was inversely associated with diabetes risk, including for total flavonoids (HR: 0.67; 95% CI: 0.48, 0.93; P-trend = 0.02), stilbenes (HR: 0.57; 95% CI: 0.38, 0.84; P-trend = 0.003), dihydroflavonols (HR: 0.59; 95% CI: 0.40, 0.88; P-trend = 0.003), and flavanones (HR: 0.69; 95% CI: 0.49, 0.97; P-trend = 0.03).

CONCLUSIONS

A high intake of total polyphenols, total flavonoids (specifically flavanones and dihydroflavonols), and stilbenes is associated with a reduced risk of diabetes in elderly persons at high risk of cardiovascular disease. This trial was registered at http://www.controlled-trials.com as ISRCTN35739639.