Pressor effect of alcohol in hypertension

Respiratory modulation of the heart rate: A potential biomarker of cardiorespiratory function in human

In recent decade, wearable digital devices have shown potentials for the discovery of novel biomarkers of humans' physiology and behavior. Heart rate (HR) and respiration rate (RR) are most crucial bio-signals in humans' digital phenotyping research. HR is a continuous and non-invasive proxy to autonomic nervous system and ample evidence pinpoints the critical role of respiratory modulation of cardiac function. In the present study, we recorded longitudinal (7 days, 4.63 ± 1.52) HR and RR of 89 freely behaving human subjects (Female: 39, age 57.28 ± 5.67, Male: 50, age 58.48 ± 6.32) and analyzed their dynamics using linear models and information theoretic measures. While HR's linear and nonlinear characteristics were expressed within the plane of the HR-RR directed flow of information (HR→RR - RR→HR), their dynamics were determined by its RR→HR axis. More importantly, RR→HR quantified the effect of alcohol consumption on individuals' cardiorespiratory function independent of their consumed amount of alcohol, thereby signifying the presence of this habit in their daily life activities. The present findings provided evidence for the critical role of the respiratory modulation of HR, which was previously only studied in non-human animals. These results can contribute to humans' phenotyping research by presenting RR→HR as a digital diagnosis/prognosis marker of humans' cardiorespiratory pathology.

Reactive Oxygen Species Are Central Mediators of Vascular Dysfunction and Hypertension Induced by Ethanol Consumption

Consumption of high amounts of ethanol is a risk factor for development of cardiovascular diseases such as arterial hypertension. The hypertensive state induced by ethanol is a complex multi-factorial event, and oxidative stress is a pathophysiological hallmark of vascular dysfunction associated with ethanol consumption. Increasing levels of reactive oxygen species (ROS) in the vasculature trigger important processes underlying vascular injury, including accumulation of intracellular Ca2+ ions, reduced bioavailability of nitric oxide (NO), activation of mitogen-activated protein kinases (MAPKs), endothelial dysfunction, and loss of the anticontractile effect of perivascular adipose tissue (PVAT). The enzyme nicotinamide adenine dinucleotide phosphate (NADPH) oxidase plays a central role in vascular ROS generation in response to ethanol. Activation of the renin-angiotensin-aldosterone system (RAAS) is an upstream mechanism which contributes to NADPH oxidase stimulation, overproduction of ROS, and vascular dysfunction. This review discusses the mechanisms of vascular dysfunction induced by ethanol, detailing the contribution of ROS to these processes. Data examining the association between neuroendocrine changes and vascular oxidative stress induced by ethanol are also reviewed and discussed. These issues are of paramount interest to public health as ethanol contributes to blood pressure elevation in the general population, and it is linked to cardiovascular conditions and diseases.

Alcohol Intake and Arterial Hypertension: Retelling of a Multifaceted Story

Alcoholic beverages are common components of diets worldwide and understanding their effects on humans' health is crucial. Because hypertension is the leading risk factor for cardiovascular diseases and all-cause mortality, the relationship of alcohol consumption with blood pressure (BP) has been the subject of extensive investigation. For the purpose of this review, we searched the terms "alcohol", "ethanol", and "arterial hypertension" on Pubmed MeSH and selected the most relevant studies. Short-term studies showed a biphasic BP response after ingestion of high doses of alcohol, and sustained alcohol consumption above 30 g/day, significantly, and dose-dependently, increased the risk for hypertension. These untoward effects of alcoholic beverages on BP can be mediated by a multiplicity of neurohormonal mechanisms. In addition to the effects on BP, excess alcohol intake might contribute to cardiac and renal hypertensive organ damage, although some studies suggest possible benefits of moderate alcohol consumption on additional cardiovascular risk factors, such as diabetes and lipoprotein(a). Some intervention studies and cumulative analyses support the evidence of a benefit of the reduction/withdrawal of alcohol consumption on BP and cardiovascular outcomes. This is why guidelines of scientific societies recommend avoidance or limitation of alcohol intake below one unit/day for women and two units/day for men. This narrative article overviews all these topics, providing an update of the current knowledge on the relationship between alcohol and BP.

Association of Alcohol Intake With Hypertension in Type 2 Diabetes Mellitus: The ACCORD Trial

Background Heavy alcohol consumption has a well-established association with hypertension. However, doubt persists whether moderate alcohol consumption has a similar link. This relationship is not well-studied in patients with diabetes mellitus. We aimed to describe the association of alcohol consumption with prevalent hypertension in participants in the ACCORD (Action to Control Cardiovascular Risk in Diabetes) trial. Methods and Results Alcohol consumption was categorized as none, light (1-7 drinks/week), moderate (8-14 drinks/week), and heavy (≥15 drinks/week). Blood pressure was categorized using American College of Cardiology/American Heart Association guidelines as normal, elevated blood pressure, stage 1 hypertension, and stage 2 hypertension. Multivariable logistic regression was used to explore the association between alcohol consumption and prevalent hypertension. A total of 10 200 eligible participants were analyzed. Light alcohol consumption was not associated with elevated blood pressure or any stage hypertension. Moderate alcohol consumption was associated with elevated blood pressure, stage 1, and stage 2 hypertension (odds ratio [OR], 1.79; 95% CI, 1.04-3.11, P=0.03; OR, 1.66; 95% CI, 1.05-2.60, P=0.03; and OR, 1.62; 95% CI, 1.03-2.54, P=0.03, respectively). Heavy alcohol consumption was associated with elevated blood pressure, stage 1, and stage 2 hypertension (OR, 1.91; 95% CI, 1.17-3.12, P=0.01; OR, 2.49; 95% CI, 1.03-6.17, P=0.03; and OR, 3.04; 95% CI, 1.28-7.22, P=0.01, respectively). Conclusions Despite prior research, our findings show moderate alcohol consumption is associated with hypertension in patients with type 2 diabetes mellitus and elevated cardiovascular risk. We also note a dose-risk relationship with the amount of alcohol consumed and the degree of hypertension.

Effect of alcohol on blood pressure

BACKGROUND

Alcohol is consumed by over 2 billion people worldwide. It is a common substance of abuse and its use can lead to more than 200 disorders including hypertension. Alcohol has both acute and chronic effects on blood pressure. This review aimed to quantify the acute effects of different doses of alcohol over time on blood pressure and heart rate in an adult population.

OBJECTIVES

Primary objective To determine short-term dose-related effects of alcohol versus placebo on systolic blood pressure and diastolic blood pressure in healthy and hypertensive adults over 18 years of age. Secondary objective To determine short-term dose-related effects of alcohol versus placebo on heart rate in healthy and hypertensive adults over 18 years of age.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to March 2019: the Cochrane Hypertension Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 2), in the Cochrane Library; MEDLINE (from 1946); Embase (from 1974); the World Health Organization International Clinical Trials Registry Platform; and ClinicalTrials.gov. We also contacted authors of relevant articles regarding further published and unpublished work. These searches had no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing effects of a single dose of alcohol versus placebo on blood pressure (BP) or heart rate (HR) in adults (≥ 18 years of age).

DATA COLLECTION AND ANALYSIS

Two review authors (ST and CT) independently extracted data and assessed the quality of included studies. We also contacted trial authors for missing or unclear information. Mean difference (MD) from placebo with 95% confidence interval (CI) was the outcome measure, and a fixed-effect model was used to combine effect sizes across studies.  MAIN RESULTS: We included 32 RCTs involving 767 participants. Most of the study participants were male (N = 642) and were healthy. The mean age of participants was 33 years, and mean body weight was 78 kilograms. Low-dose alcohol (< 14 g) within six hours (2 RCTs, N = 28) did not affect BP but did increase HR by 5.1 bpm (95% CI 1.9 to 8.2) (moderate-certainty evidence). Medium-dose alcohol (14 to 28 g) within six hours (10 RCTs, N = 149) decreased systolic blood pressure (SBP) by 5.6 mmHg (95% CI -8.3 to -3.0) and diastolic blood pressure (DBP) by 4.0 mmHg (95% CI -6.0 to -2.0) and increased HR by 4.6 bpm (95% CI 3.1 to 6.1) (moderate-certainty evidence for all).  Medium-dose alcohol within 7 to 12 hours (4 RCTs, N = 54) did not affect BP or HR. Medium-dose alcohol > 13 hours after consumption (4 RCTs, N = 66) did not affect BP or HR. High-dose alcohol (> 30 g) within six hours (16 RCTs, N = 418) decreased SBP by 3.5 mmHg (95% CI -6.0 to -1.0), decreased DBP by 1.9 mmHg (95% CI-3.9 to 0.04), and increased HR by 5.8 bpm (95% CI 4.0 to 7.5). The certainty of evidence was moderate for SBP and HR, and was low for DBP. High-dose alcohol within 7 to 12 hours of consumption (3 RCTs, N = 54) decreased SBP by 3.7 mmHg (95% CI -7.0 to -0.5) and DBP by 1.7 mmHg (95% CI -4.6 to 1.8) and increased HR by 6.2 bpm (95% CI 3.0 to 9.3). The certainty of evidence was moderate for SBP and HR, and low for DBP. High-dose alcohol ≥ 13 hours after consumption (4 RCTs, N = 154) increased SBP by 3.7 mmHg (95% CI 2.3 to 5.1), DBP by 2.4 mmHg (95% CI 0.2 to 4.5), and HR by 2.7 bpm (95% CI 0.8 to 4.6) (moderate-certainty evidence for all).  AUTHORS' CONCLUSIONS: High-dose alcohol has a biphasic effect on BP; it decreases BP up to 12 hours after consumption and increases BP > 13 hours after consumption. High-dose alcohol increases HR at all times up to 24 hours. Findings of this review are relevant mainly to healthy males, as only small numbers of women were included in the included trials.

Role of Alcohol Oxidative Metabolism in Its Cardiovascular and Autonomic Effects

Several review articles have been published on the neurobehavioral actions of acetaldehyde and other ethanol metabolites as well as in major alcohol-related disorders such as cancer and liver and lung disease. However, very few reviews dealt with the role of alcohol metabolism in the adverse cardiac and autonomic effects of alcohol and their potential underlying mechanisms, particularly in vulnerable populations. In this chapter, following a brief overview of the dose-related favorable and adverse cardiovascular effects of alcohol, we discuss the role of ethanol metabolism in its adverse effects in the brainstem and heart. Notably, current knowledge dismisses a major role for acetaldehyde in the adverse autonomic and cardiac effects of alcohol because of its low tissue level in vivo. Contrary to these findings in men and male rodents, women and hypertensive individuals are more sensitive to the adverse cardiac effects of similar amounts of alcohol. To understand this discrepancy, we discuss the autonomic and cardiac effects of alcohol and its metabolite acetaldehyde in a model of hypertension, the spontaneously hypertensive rat (SHR) and female rats. We present evidence that enhanced catalase activity, which contributes to cardioprotection in hypertension (compensatory) and in the presence of estrogen (inherent), becomes detrimental due to catalase catalysis of alcohol metabolism to acetaldehyde. Noteworthy, studies in SHRs and in estrogen deprived or replete normotensive rats implicate acetaldehyde in triggering oxidative stress in autonomic nuclei and the heart via (i) the Akt/extracellular signal-regulated kinases (ERK)/nitric oxide synthase (NOS) cascade and (ii) estrogen receptor-alpha (ERα) mediation of the higher catalase activity, which generates higher ethanol-derived acetaldehyde in female heart. The latter is supported by the ability of ERα blockade or catalase inhibition to attenuate alcohol-evoked myocardial oxidative stress and dysfunction. More mechanistic studies are needed to further understand the mechanisms of this public health problem.

Alcoholic cardiomyopathy : The result of dosage and individual predisposition

The individual amount of alcohol consumed acutely or chronically decides on harm or benefit to a person’s health. Available data suggest that one to two drinks in men and one drink in women will benefit the cardiovascular system over time, one drink being 17.6 ml 100 % alcohol. Moderate drinking can reduce the incidence and mortality of coronary artery disease, heart failure, diabetes, ischemic and hemorrhagic stroke. More than this amount can lead to alcoholic cardiomyopathy, which is defined as alcohol toxicity to the heart muscle itself by ethanol and its metabolites. Historical examples of interest are the Munich beer heart and the Tübingen wine heart. Associated with chronic alcohol abuse but having different etiologies are beriberi heart disease (vitamin B1 deficiency) and cardiac cirrhosis as hyperdynamic cardiomyopathies, arsenic poising in the Manchester beer epidemic, and cobalt intoxication in Quebec beer drinker’s disease. Chronic heavy alcohol abuse will also increase blood pressure and cause a downregulation of the immune system that could lead to increased susceptibility to infections, which in turn could add to the development of heart failure. Myocardial tissue analysis resembles idiopathic cardiomyopathy or chronic myocarditis. In the diagnostic work-up of alcoholic cardiomyopathy, the confirmation of alcohol abuse by carbohydrate deficient transferrin (CDT) and increased liver enzymes, and the involvement of the heart by markers of heart failure (e.g., NT-proBNP) and of necrosis (e.g., troponins or CKMb) is mandatory. Treatment of alcoholic cardiomyopathy consists of alcohol abstinence and heart failure medication.

Alcohol use and risk of intracerebral hemorrhage

OBJECTIVE

To analyze the dose-risk relationship for alcohol consumption and intracerebral hemorrhage (ICH) in the Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study.

METHODS

ERICH is a multicenter, prospective, case-control study, designed to recruit 1,000 non-Hispanic white patients, 1,000 non-Hispanic black patients, and 1,000 Hispanic patients with ICH. Cases were matched 1:1 to ICH-free controls by age, sex, race/ethnicity, and geographic area. Comprehensive interviews included questions regarding alcohol consumption. Patterns of alcohol consumption were categorized as none, rare (<1 drink per month), moderate (≥1 drink per month and ≤2 drinks per day), intermediate (>2 drinks per day and <5 drinks per day), and heavy (≥5 drinks per day). ICH risk was calculated using the no-alcohol use category as the reference group.

RESULTS

Multivariable analyses demonstrated an ordinal trend for alcohol consumption: rare (odds ratio [OR] 0.57, p < 0.0001), moderate (OR 0.65, p < 0.0001), intermediate (OR 0.82, p = 0.2666), and heavy alcohol consumption (OR 1.77, p = 0.0003). Subgroup analyses demonstrated an association of rare and moderate alcohol consumption with decreased risk of both lobar and nonlobar ICH. Heavy alcohol consumption demonstrated a strong association with increased nonlobar ICH risk (OR 2.04, p = 0.0003). Heavy alcohol consumption was associated with significant increase in nonlobar ICH risk in black (OR 2.34, p = 0.0140) and Hispanic participants (OR 12.32, p < 0.0001). A similar association was not found in white participants.

CONCLUSIONS

This study demonstrated potential protective effects of rare and moderate alcohol consumption on ICH risk. Heavy alcohol consumption was associated with increased ICH risk. Race/ethnicity was a significant factor in alcohol-associated ICH risk; heavy alcohol consumption in black and Hispanic participants poses significant nonlobar ICH risk.

Alcohol and cardiovascular disease in the geriatric population

There has been little focus on the effects of alcohol on the elderly. Although the cardiovascular benefits of moderate alcohol consumption could be of the greatest benefit in this group, so might be the detrimental effects of abuse. In this article, we review available data on the effects of alcohol consumption on cardiovascular disease, cardiomyopathy, arrhythmias, hypertension, and vascular function in older adults. Alcohol consumption has increased in the US population age 65 years and older in the last decade, as has monthly heavy episodic drinking in older alcohol consumers. Studies of alcohol consumption in older subjects suggest that consumption in moderation does not increase the risk of heart failure, hypertension, or atrial arrhythmias, and may in fact improve vascular function and reduce cardiovascular disease events. As in younger subjects, heavy consumption, or abuse of alcohol, negates any potential protective cardiovascular effects, increasing the incidence of heart failure and hypertension. Although alcohol consumed in moderation does not appear harmful in the elderly population, heavier consumption exacerbates hypertension and increases the incidence of heart failure.

Alcohol and cardiovascular diseases: where do we stand today?

For centuries, multiple medical risks of heavy alcohol drinking have been evident with simultaneous awareness of a less harmful or sensible drinking limit. The increased risks of heavy drinking, defined as three or more standard-sized drinks per day, are both cardiovascular (CV) and non-CV. The CV risks include the following: (i) alcoholic cardiomyopathy (ACM), (ii) systemic hypertension, (iii) atrial arrhythmias, (iv) haemorrhagic stroke and, probably, ischaemic stroke. By contrast, modern epidemiological studies have shown lower morbidity and mortality amongst light-moderate drinkers, due mostly to a reduced risk of coronary artery disease (CAD), with contributions from ischaemic stroke and heart failure (HF). A low level of alcohol drinking has no clear relation to increased risk of any CV condition, except for haemorrhagic stroke. There is good evidence that supports the existence of mechanisms by which alcohol might protect against CAD, but the mechanisms for other alcohol-CV associations remain unclear. Interrelationships amongst the CV conditions affect the individual alcohol-disease relationships; for example, lower CAD risk in light-moderate drinkers is to a large extent responsible for the reduced HF risk. International comparison data plus the presence of proposed beneficial nonalcohol components in wine (particularly in red wine) suggest that this beverage type might afford extra CAD protection. However, the effect of beverage choice is confounded by a healthier drinking pattern and more favourable risk traits in wine drinkers. Debate persists about methodological and public health issues related to the epidemiology of alcohol-related CV disease.

Cardiovascular risks and benefits of moderate and heavy alcohol consumption

The heart and vascular system are susceptible to the harmful effects of alcohol. Alcohol is an active toxin that undergoes widespread diffusion throughout the body, causing multiple synchronous and synergistic effects. Alcohol consumption decreases myocardial contractility and induces arrhythmias and dilated cardiomyopathy, resulting in progressive cardiovascular dysfunction and structural damage. Alcohol, whether at binge doses or a high cumulative lifetime consumption-both of which should be discouraged-is clearly deleterious for the cardiovascular system, increasing the incidence of total and cardiovascular mortality, coronary and peripheral artery disease, heart failure, stroke, hypertension, dyslipidaemia, and diabetes mellitus. However, epidemiological, case-control studies and meta-analyses have shown a U-type bimodal relationship so that low-to-moderate alcohol consumption (particularly of wine or beer) is associated with a decrease in cardiovascular events and mortality, compared with abstention. Potential confounding influences-alcohol-dose quantification, tobacco use, diet, exercise, lifestyle, cancer risk, accidents, and dependence-can affect the results of studies of both low-dose and high-dose alcohol consumption. Mendelian methodological approaches have led to doubts regarding the beneficial cardiovascular effects of alcohol, and the overall balance of beneficial and detrimental effects should be considered when making individual and population-wide recommendations, as reductions in alcohol consumption should provide overall health benefits.

[Wine: Good for all cardiovascular diseases?]

Beneficial effects of wine are mainly due to polyphenol components with a major role for resveratrol. Moderate wine consumption decreases cardiovascular mortality. Very favorable effects in coronary artery disease and cholesterol. Deleterious effects in systemic hypertension and dilated cardiomyopathy.

RECOMMENDATION

1 to 2 drinks (10 to 20g of alcohol) per day.

Alcohol-induced hypertension: Mechanism and prevention

Epidemiological, preclinical and clinical studies established the association between high alcohol consumption and hypertension. However the mechanism through which alcohol raises blood pressure remains elusive. Several possible mechanisms have been proposed such as an imbalance of the central nervous system, impairment of the baroreceptors, enhanced sympathetic activity, stimulation of the renin-angiotensin-aldosterone system, increased cortisol levels, increased vascular reactivity due to increase in intracellular calcium levels, stimulation of the endothelium to release vasoconstrictors and loss of relaxation due to inflammation and oxidative injury of the endothelium leading to inhibition of endothelium-dependent nitric oxide production. Loss of relaxation due to inflammation and oxidative injury of the endothelium by angiotensin II leading to inhibition of endothelium-dependent nitric oxide production is the major contributors of the alcohol-induced hypertension. For the prevention of alcohol-induced hypertension is to reduce the amount of alcohol intake. Physical conditioning/exercise training is one of the most important strategies to prevent/treat chronic alcohol-induced hypertension on physiological basis. The efficacious pharmacologic treatment includes the angiotensin-converting enzyme (ACE) inhibitors or angiotensin II type 1 receptor blockers (ARBs) which have antioxidant activity and calcium channel blockers. The most effective prevention and treatment of alcohol-induced hypertension is physical exercise and the use of ACE inhibitors or ARBs in the clinic

Hypertension and chronic ethanol consumption: What do we know after a century of study?

The influences of life habits on the cardiovascular system may have important implications for public health, as cardiovascular diseases are among the leading causes of shorter life expectancy worldwide. A link between excessive ethyl alcohol (ethanol) consumption and arterial hypertension was first suggested early last century. Since then, this proposition has received considerable attention. Support for the concept of ethanol as a cause of hypertension derives from several epidemiologic studies demonstrating that in the general population, increased blood pressure is significantly correlated with ethanol consumption. Although the link between ethanol consumption and hypertension is well established, the mechanism through which ethanol increases blood pressure remains elusive. Possible mechanisms underlying ethanol-induced hypertension were proposed based on clinical and experimental observations. These mechanisms include an increase in sympathetic nervous system activity, stimulation of the renin-angiotensin-aldosterone system, an increase of intracellular Ca²⁺ in vascular smooth muscle, increased oxidative stress and endothelial dysfunction. The present report reviews the relationship between ethanol intake and hypertension and highlights some mechanisms underlying this response. These issues are of interest for the public health, as ethanol consumption contributes to blood pressure elevation in the population.

Substance Use and Associated Health Conditions throughout the Lifespan

A life stage perspective is necessary for development of age-appropriate strategies to address substance use disorders (SUDs) and related health conditions in order to produce better overall health and well-being. The current review evaluated the literature across three major life stages: adolescence, adulthood, and older adulthood.

FINDINGS

1) Substance use is often initiated in adolescence, but it is during adulthood that prevalence rates for SUDs peak; and while substance involvement is less common among older adults, the risk for health complications associated with use increases. 2) Alcohol, tobacco, marijuana, and, increasingly, prescription medications, are the most commonly misused substances across age groups; however, the use pattern of these and other drugs and the salient impact vary depending on life stage. 3) In terms of health outcomes, all ages are at risk for overdose, accidental injury, and attempted suicide. Adolescents are more likely to be in vehicular accidents while older adults are at greater risk for damaging falls. Adulthood has the highest rates of associated medical conditions (e.g., cancer, sexually transmitted disease, heart disease) and mental health conditions (e.g., bipolar disorder, anxiety disorders, antisocial personality disorder).

CONCLUSION

Prolonged heavy use of drugs and/or alcohol results in an array of serious health conditions. Addressing SUDs from a life stage perspective with assessment and treatment approaches incorporating co-occurring disorders are necessary to successfully impact overall health.

Endothelial dysfunction and high cardiovascular risk profile in severe alcoholics improve only partially following a medium-term alcohol withdrawal

BACKGROUND

Little is known about brachial artery flow-mediated vasodilatation (FMD) in active and medium-term withdrawing heavy alcoholics (HA).

METHODS

FMD and some parameters of cardiovascular (CV) risk were measured in 29 HA (average alcohol intake 135, range 86 to 215 g per day) at baseline and after a 9 ± 7 months withdrawal and in 35 teetotalers.

RESULTS

HA showed baseline impaired maximal % FMD (8.5 ± 5.4 SD vs. 14.9 ± 7.4, <0.001 vs. teetotalers), higher systolic (SBP) and diastolic (DBP) blood pressure (+24 mm Hg, <0.001; +15 mm Hg, <0.01), uric acid (5.3 ± 1.1 vs. 4.4 ± 0.8 mg/dl, <0.05), high-sensitivity C-reactive protein (hs-CRP; 2.7 ± 2.0 vs. 1.0 ± 0.9 mg/l, <0.02), endothelin-1 (ET-1, 0.88 ± 0.36 vs. 0.37 ± 0.10 pg/ml,<0.001), asymmetric dimethylarginine (ADMA, 0.50 ± 0.21 vs. 0.41 ± 0.12 μmol/l, p < 0.001), homeostasis model assessment of insulin resistance (HOMA-IR) (2.3 ± 1.1 vs. 1.2 ± 0.4, <0.001), and urinary 8-isoprostane (U8-iso-PGF2α) (237.2 ± 172.4 vs. 168.5 ± 96.6 pg/mg creatinine, <0.05). After withdrawal, SBP fell by 15 mm Hg, DBP by 11 mm Hg (p < 0.001), and hs-CRP by 0.94 mg/l (p < 0.02), all remaining still higher than teetotalers (<0.05, 0.01, 0.05 respectively). ET-1, HOMA-IR, and U8-iso-PGF2α were unchanged (p = NS vs. baseline, <0.05 to 0.001 vs. teetotalers). Maximal % FMD rose (to 10.6 ± 6.2, p < 0.04), but it still remained impaired (<0.04 vs. teetotalers). ADMA increased further to 0.64 ± 0.15 μmol/l (<0.05 vs. baseline, <0.02 vs. teetotalers).

CONCLUSIONS

HA show marked endothelial dysfunction (ED) and high BP, impaired insulin sensitivity, inflammation, increased oxidative stress, and elevated ET-1 and ADMA, which are unaffected or only partially reversed by a medium-term alcohol withdrawal. ED and related abnormalities persist in detoxified alcoholics, thus contributing to a greater CV morbidity and mortality.

Non-pharmacological aspects of blood pressure management: what are the data?

Hypertension affects 29% of US adults and is a significant risk factor for cardiovascular morbidity and mortality. Epidemiological data support contribution of several dietary and other lifestyle-related factors to the development of high blood pressure (BP). Several clinical trials investigated the efficacy of non-pharmacological interventions and lifestyle modifications to reduce BP. Best evidence from randomized controlled trials supports BP-lowering effects of weight loss, the Dietary Approaches to Stop Hypertension (DASH) diet, and dietary sodium (Na(+)) reduction in those with prehypertension, with more pronounced effects in those with hypertension. In hypertensive participants, the effects on BP of DASH combined with low Na(+) alone or with the addition of weight loss were greater than or equal to those of single-drug therapy. Trials where food was provided to participants were more successful in showing a BP-lowering effect. However, clinical studies with long-term follow-up revealed that lifestyle modifications were difficult to maintain. Findings from controlled trials of increased potassium, calcium, or magnesium intake, or reduction in alcohol intake revealed modest BP-lowering effects and are less conclusive. The reported effects of exercise independent of weight loss on BP are inconsistent.

Upregulation of cardiac NOS due to endotoxemia and vagal overactivity contributes to the hypotensive effect of chronic ethanol in female rats

We previously reported that chronic ethanol lowers blood pressure in female rats. In this study, hemodynamic, biochemical, and immunoblot analyses were performed to investigate: (i) the roles of cardiac contractility and autonomic activity in the hypotensive action of ethanol, and (ii) whether endotoxemia-induced upregulation of cardiac and/or vascular nitric oxide synthase (NOS) isoforms underlies the hypotensive and cardiac effects of ethanol. Telemetric monitoring of blood pressure, heart rate, and myocardial contractility (dP/dt(max)) was performed in female rats receiving liquid diet with or without ethanol (5% w/v, 13weeks). Autonomic control was assessed by frequency domain analysis of interbeat intervals (IBI) and systolic blood pressure (SBP). Compared with pair-fed controls, ethanol caused sustained reductions in blood pressure, heart rate, and+dP/dt(max). Ethanol feeding increased the spectral power of high-frequency band (IBI(HF), 0.75-3Hz) and decreased the low-frequency band (IBI(LF), 0.25-0.75Hz) and IBI(LF/HF) ratio, suggesting increased cardiac parasympathetic dominance. In contrast, vascular tone was not affected by ethanol because SBP spectral bands and plasma norepinephrine remained unchanged. Myocardial expressions of eNOS and its upstream regulators, phosphatidylinositol 3-kinase (PI3K) and Akt, and plasma endotoxin and nitrite/nitrate were increased by ethanol. Myocardial iNOS was also increased by ethanol whereas nNOS remained unchanged and aortic levels of all NOS isoforms were not altered by ethanol. These findings suggest that facilitation of myocardial PI3K/Akt/eNOS and iNOS pathways, due possibly to ethanol-induced endotoxemia and/or increased cardiac parasympathetic dominance, might constitute a cellular mechanism for the reduced myocardial contractility and hypotension caused by ethanol in female rats.

Grapes, wines, resveratrol, and heart health

Epidemiological and experimental studies have revealed that a mild to moderate drinking of wine, particularly red wine, attenuates the cardiovascular, cerebrovascular, and peripheral vascular risk. However, the experimental basis for such health benefits is not fully understood. The cardioprotective effect of wine has been attributed to both components of wine: the alcoholic portion and, more importantly, the alcohol-free portion containing antioxidants. Wines are manufactured from grapes, which also contain a large variety of antioxidants, including resveratrol, catechin, epicatechin, and proanthocyanidins. Resveratrol is mainly found in the grape skin, whereas proanthocyanidins are found only in the seeds. Recent studies have demonstrated that resveratrol and proanthocyanidin are the major compounds present in grapes and wines responsible for cardioprotection. The purpose of this review is to provide evidence that grapes, wines, and resveratrol are equally important in reducing the risk of morbidity and mortality due to cardiovascular complications. Both wines and grapes can attenuate cardiac diseases such as atherosclerosis and ischemic heart disease. Recently, wine was also found to increase life span by inducing longevity genes. It appears that resveratrol and proanthocyanidins, especially resveratrol, present in grapes and wines play a crucial role in cardioprotective abilities of grapes and wines.

Alcohol and cardiovascular health

The substantial medical risks of heavy alcohol drinking as well as the probable existence of a less harmful or safe drinking limit have been evident for centuries. Modern epidemiology studies suggest lowered risk of morbidity and mortality among lighter drinkers. Thus, defining "heavy" drinking as > or =3 standard drinks per day, the alcohol-mortality relationship is a J-curve with risk highest for heavy drinkers, lowest for light drinkers and intermediate for abstainers. A number of non-cardiovascular and cardiovascular problems contribute to the increased mortality risk of heavier drinkers. The lower risk of light drinkers is due mostly to lower risk of the most common cardiovascular condition, coronary heart disease (CHD). These disparate relationships of alcoholic drinking to various cardiovascular and non-cardiovascular conditions constitute a modern concept of alcohol and health. Increased cardiovascular risks of heavy drinking include: (1) alcoholic cardiomyopathy, (2) systemic hypertension (high blood pressure), (3) heart rhythm disturbances, and (4) hemorrhagic stroke. Lighter drinking is not clearly related to increased risk of any cardiovascular condition and, in observational studies, is related to lower risk of CHD, ischemic stroke, and diabetes mellitus. A protective hypothesis for CHD is supported by evidence for plausible biological mechanisms attributable to ethyl alcohol. International comparisons and some prospective study data suggest that wine is more protective against CHD than liquor or beer. Possible non-alcohol beneficial components in wine (especially red) support possible extra protection by wine, but a healthier pattern of drinking or more favorable risk traits in wine drinkers may be involved.

Alcohol, cardiovascular diseases and all causes of death: a review of the epidemiological evidence

This paper reviews the epidemiological evidence on the association of alcohol consumption with the major cardiovascular diseases (hypertension, stroke and coronary heart disease), and all causes of death. The focus is on light and moderate consumption and several important methodological issues are apparent with the epidemiological evidence on alcohol and mortality. The epidemiological data justify the following recommendations on alcohol consumption. The evidence does not support the unqualified claim that light and moderate drinking confers overall health benefits. However, in persons over 35 years of age, there is no consistent evidence that daily consumption of up to 2-3 drinks in men or up to 1-2 drinks in women increases the risk of dying. Non-drinkers should not be encouraged to change their drinking status. The consumption of more than 2-3 drinks per day in men and more than 1-2 drinks per day in women should be actively discouraged. Further research on the effects of light and moderate alcohol consumption on cardiovascular disease and all causes of death are required, particularly in young people, women and the elderly.

What supports the role of alcohol as a risk factor for stroke?

For more than 30 years, clinical observations to link alcohol abuse and stroke have accumulated in several countries. Studies of general populations have indicated that the risk for stroke increases with increasing alcohol consumption. Studies of young victims of stroke where the classical risk factors of stroke are uncommon, have demonstrated that even occasional heavy drinking carries an increased risk for stroke. In particular, the increased occurrence of strokes during weekends, the very time of heavy alcohol consumption in non-alcoholics, supports this notion. Alcoholics seem to get their strokes at an earlier age than non-alcoholics. Paradoxically, the published evidence has implicated drinking in both ischemic and hemorrhagic strokes, which suggests that there may be more than one mechanism by which alcohol can increase the risk. Strokes seem to be precipitated during the alcohol intoxication itself rather than the following withdrawal syndrome, but the contributing mechanisms, except for bleedings caused by external violence, are unknown. Alcohol can produce fluctuations in platelet reactivity and untoward interactions with certain drugs, but it remains to be demonstrated that such effects are temporally related to the onset of ischemic and hemorrhagic strokes.

Dietary factors and hypertension

There is increasing evidence that nutritional factors are critical in the pathogenesis of essential hypertension typical for acculturated societies. These factors include sodium, potassium, calcium, alcohol, and type and level of fat in the diet. More research is needed, however, before the role of various nutrients in the prevention and treatment of hypertension will be ascertained.

Effects of antihypertensive drugs on alcohol-induced functional responses of cultured human endothelial cells

Alcohol-induced endothelial changes might contribute to an increase in blood pressure in regular alcohol consumers. Some antihypertensive drugs affect oxidative stress and endothelial function and might counteract the effects of alcohol at the cellular level. The aim of this study was to investigate in vitro the effects of three different types of antihypertensive agents on alcohol-induced endothelial responses and oxidative stress. Cultured human endothelial cells were exposed to increasing concentrations (1, 10, 60 micromol/L) of zofenoprilat, carvedilol, and lacidipine in the absence and in the presence of ethanol (140 mmol/L). Concentrations of endothelin (ET) and nitric oxide (NO) were measured in the culture media as markers of endothelial function, and malondialdehyde (MDA) and intracellular glutathione (GSHi) were measured as markers of oxidative stress. Exposure to alcohol increased the levels of ET, NO, and MDA, and decreased GSHi. Carvedilol and zofenoprilat were more effective than lacidipine in counteracting the effects of alcohol on ET production. Alcohol-induced NO production was enhanced by carvedilol, whereas zofenoprilat and lacidipine did not have a significant effect. The alcohol-induced increase in MDA concentrations was blunted by all three drugs, but only carvedilol restored a normal response. All three drugs increased GSHi levels, with the effect being greater for carvedilol and lacidipine than zofenoprilat. Carvedilol is more effective than zofenoprilat and lacidipine in counteracting alcohol-induced endothelial responses in vitro and in decreasing oxidative stress. These effects might be particularly beneficial in patients with alcohol-related hypertension.

Role of Myocardial Contractility and Autonomic Control in the Hypotensive Response to a Limited Access Ethanol Paradigm in SHRs

BACKGROUND

Previous experimental studies that evaluated the chronic hemodynamic effect of ethanol employed the continuous exposure protocol of ethanol, which does not mimic the pattern of alcohol consumption in humans. This study dealt with the long-term hemodynamic and cardiovascular autonomic effects of ethanol, in a limited-access regimen in telemetered spontaneously hypertensive rats (SHRs).

METHODS

Changes in blood pressure (BP), heart rate (HR), myocardial contractility (dP/dt(max)), and spectral cardiovascular autonomic profiles during the ethanol exposure period (2.5 or 5% w/v, 8 h/d, 8:30 am till 4:30 pm) were followed for 12 weeks.

RESULTS

Compared with control pair-fed SHRs, body weight and urine output, osmolality, and potassium levels were decreased in SHRs receiving 5% but not 2.5% ethanol. Blood pressure showed progressive falls during ethanol-feeding periods with a maximum effect observed at week 5. The peak hypotensive effect was maintained thereafter in SHRs receiving 5% ethanol in contrast to steady rises in BP in the 2.5% ethanol group to near-control levels by the conclusion of the study. Heart rate was slightly but significantly increased by ethanol 5% whereas dP/dt(max) showed persistent reductions. Power spectral analysis showed that ethanol attenuated the baroreflex gain of HR as suggested by the reductions in index alpha, the spectral index of spontaneous baroreflex sensitivity (BRS).

CONCLUSIONS

It is concluded that limited access ethanol drinking in SHRs elicited hypotension that was concentration dependent and mediated, at least partly, through reductions in myocardial contractility. Baroreflex sensitivity attenuation by ethanol appeared to have limited the tachycardic response to ethanol and perhaps its capacity to offset the evoked hypotension.

Alcohol consumption and blood pressure in the adult US population: assessment of gender-related effects

OBJECTIVE

Our objective was to assess the gender-related effects of alcohol consumption on blood pressure (BP) in a representative sample of the adult US population.

METHODS

We examined data from the National Health and Nutrition Examination Survey 1999-2000. The effects of various risk factors for hypertension on BP were examined with analysis of covariance statistics.

RESULTS

Of the 5448 adults over 20 years of age, 2650 (48.7%) reported the intake of one or more drinks per day over the past year. In this population, the mean +/- SEM age was 46.9 +/- 0.34 years, the body mass index was 24.8 kg/m, 1257 (47.4%) were women, systolic BP was 124.3 +/- 0.44 mmHg and diastolic BP was 72.7 +/- 0.27 mmHg. Hypertension was reported in 21.1%, diabetes in 5.1% and cigarette smoking in 39.7%. A significant effect on systolic BP was shown with age (P < 0.01), body mass index (P < 0.01), race (P = 0.01), gender (P < 0.01) and diabetes (P < 0.01). The interaction with gender and alcohol drinking level was significant (P = 0.02). Post-hoc analysis localized the source of this effect. There was a significant increase in systolic BP between one and three and between one and four, but not between one and two, drinks per day in men. This effect was not observed in women.

CONCLUSION

Consistent with previous reports, our study suggests that alcohol intake up to two drinks per day has no effect on BP. There was a gender-related effect of alcohol intake in excess of two drinks per day on BP, with increased BP observed only in men but not in women.

The effect of short-term lyophilized beer consumption on established hypertension in rats

Effects of short-term lyophilized beer (LB) consumption on normotensive (WKY) and hypertensive (SHR) rats are reported. It was found that LB contains high quantities of bioactive compounds and has a high antioxidant potential. The WKY and SHR rats were divided into four groups of 8, two experimental and two controls, which were named LBWKY and LBSHR and ControlWKY and ControlSHR, respectively. LB was given to the rats of the LBWKY and LBSHR groups intragastrically at a dose of 2.72 g/kg in a volume of 10 ml/kg for 10 days. The rats of the control groups received saline solution. The following indices were determined: body weight gain, heart rate, systolic blood pressure, using a tail cuff method and GABA accumulation in the hypothalamus and the pons-medulla as measured by GABA-T inhibition. It was found that the treatment of rats with LB had no effect on the blood pressure and heart rate values. In both rat strains, LB decreased GABA accumulation in the hypothalamus and the pons-medulla. A significant reduction of body weight gain was observed in both LB-treated groups when compared with the corresponding controls. In conclusion, LB contains high quantities of bioactive compounds and possesses a high antioxidant potential. Diet supplemented with LB causes significant reduction of the central GABAergic activity in WKY and SHR rats without any effect on cardiovascular function. In addition, in both animal strains there was an apparent inverse association between LB intake and body weight gains.

Effects of alcohol withdrawal on blood pressure in hypertensive heavy drinkers

BACKGROUND

Epidemiological investigations have demonstrated a close association between heavy alcohol consumption and hypertension. The mechanisms of this association, however, remain elusive. We studied the effects of alcohol withdrawal on blood pressure, hormonal parameters, and circulating markers of endothelial activity.

METHODS

In 14 hypertensive heavy alcohol consumers (> 200 g/day) who agreed to participate in a hospital withdrawal programme we monitored, for 30 days, blood pressure, plasma levels of renin, aldosterone, cortisol, endothelin, and plasminogen activator inhibitor 1 (PAI-1), and urinary levels of catecholamines. Patients in the withdrawal group were compared with eight hypertensive heavy drinkers who refused to participate in the programme and maintained regular alcohol consumption and 11 normotensive teetotalers.

RESULTS

By the third day after withdrawal, blood pressure was significantly decreased and the normalization of levels was obtained in 13 of 14 patients by the end of the study. Alcohol withdrawal significantly decreased plasma aldosterone and cortisol levels, but did not affect levels of active renin and fractionated urinary catecholamines. At baseline, plasma endothelin and PAI-1 levels were significantly higher in alcoholic individuals than in teetotalers, and after the cessation of alcohol intake decreased progressively, reaching levels different from baseline within 1 week. A significant correlation was found between changes in endothelin and PAI-1, and blood pressure variations during alcohol abstinence that remained significant only for endothelin with the multivariate approach.

CONCLUSION

Hypertension is rapidly reversible in the majority of heavy drinkers after the withdrawal of alcohol consumption. In these patients, hypertension is associated with an increased release of endothelial factors that might contribute to the increase in blood pressure.

Liver cirrhosis and arterial hypertension

Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems (renin-angiotensin-aldosterone system, sympathetic nervous system, release of vasopressin), and resistance to vasopressors. The vasodilatory state is mediated through adrenomedullin, calcitonin gene-related peptide, nitric oxide, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective (although relative) counterbalance to increased arterial blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension (essential, secondary) may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most likely includes the combination of vasodilatation and vasoconstriction in parallel.

Upregulation of vascular inducible nitric oxide synthase mediates the hypotensive effect of ethanol in conscious female rats

Previous reports from our laboratory have shown that ethanol elicits hypotension in female but not in male rats and that this effect of ethanol is estrogen dependent (El-Mass MM and Abdel-Rahman AA. Alcohol Clin Exp Res 23: 624-632, 1999; El-Mass MM and Abdel-Rahman AA. Clin Exp Hypertens 21: 1429-1445, 1999). In the present study, we tested the hypothesis that ethanol lowers blood pressure in female rats via upregulation of the inducible nitric oxide synthase (iNOS) in vascular tissues. The effects of pretreatment with NG-nitro-L-arginine (NOARG; nonselective nitric oxide synthase inhibitor) or aminoguanidine (selective iNOS inhibitor) on hemodynamic responses elicited by intragastric (ig) ethanol were determined in conscious female rats. Changes in vascular (aortic) iNOS protein expression evoked by ethanol in the presence and absence of aminoguanidine were also measured by immunohistochemistry. Compared with control (water treated) female rats, ethanol (1 g/kg ig) elicited hypotension that was associated with a significant increase in the aortic iNOS activity. The hypotensive effect of ethanol was virtually abolished in rats infused with the nitric oxide synthase inhibitor NOARG, suggesting a role for nitric oxide in ethanol hypotension. The inability of ethanol to lower blood pressure in NOARG-treated rats cannot be attributed to the presence of elevated blood pressure in these rats because ethanol produced hypotension when blood pressure was raised to comparable levels with phenylephrine infusion. Selective inhibition of iNOS by aminoguanidine (45 mg/kg ip), which had no effect on baseline blood pressure, abolished both the hypotensive action of subsequently administered ethanol and the associated increases in aortic iNOS content. These findings implicate vascular iNOS, at least partly, in the acute hypotensive action of ethanol in female rats.

Autonomic Modulation of Altered Diurnal Hemodynamic Profiles in Ethanol-Fed Hypertensive Rats

BACKGROUND

A recent report from the authors' laboratory showed that circadian hemodynamic rhythms are altered in hypertension due partly to irregularities in cardiovascular autonomic control. This study investigated the long-term effects of chronic ethanol feeding (5% w/v, 12 weeks) on the circadian profiles of blood pressure (BP), heart rate (HR), and their variability in spontaneously hypertensive rats (SHRs) and age-matched Wistar-Kyoto (WKY) rats.

METHODS

Radiotelemetry was used for hemodynamic monitoring. The time-domain measures of the variability of BP (standard deviation of mean arterial pressure [SDMAP]) and HR (standard deviation of R-R intervals [SDRR] and root mean square of successive differences in R-R intervals [rMSSD]) were taken as indices of cardiovascular autonomic activity.

RESULTS

Control WKY rats displayed normal circadian rhythms (i.e., higher dark-time compared with light-time values) of BP, HR, and their variability indices during weeks 6 through 12 of the study. These circadian rhythms were abolished (BP), inverted (HR, SDMAP), or enhanced (SDRR, rMSSD) in SHRs. Ethanol feeding produced sustained hypotension during both light and dark cycles that was 3-fold greater in SHRs than in WKY rats. SDMAP was not affected by ethanol in WKY rats and showed reductions, mostly during light times, in SHRs. Ethanol also caused significant increases in HR in SHRs only during dark periods, probably because of the inhibition of cardiac vagal activity as indicated by temporal reductions in rMSSD.

CONCLUSIONS

These results implicate autonomic factors in the altered diurnal hemodynamic profile by ethanol in SHRs and highlight the possibility of increased risk of cardiac events in hypertensive patients due to alcohol use.

Hypertension and liver disease

Arterial hypertension is a common disorder with a frequency of 10% to 15% in subjects in the 40- to 60-year age group. Yet most reports find the prevalence of arterial hypertension in patients with chronic liver disease (cirrhosis) much lower. In this review, we consider the alterations in systemic hemodynamics in cirrhosis. The most characteristic findings in cirrhotic patients are vasodilatation with low systemic vascular resistance, increased cardiac output, high arterial compliance, secondary activation of counterregulatory systems (sympathetic nervous system, renin-angiotensin-aldosterone system, neuropituitary release of vasopressin), and resistance to vasopressors. The vasodilatory state is mediated through nitric oxide, calcitonin gene-related peptide, adrenomedullin, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective (although relative) counterbalance to increased arterial blood pressure. Subjects with established arterial hypertension (essential, secondary) may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homeostatic regulation in cirrhotic patients with manifest arterial hypertension. This is a topic for future research.

Chronic ethanol administration attenuates imidazoline I1 receptor- or alpha 2-adrenoceptor-mediated reductions in blood pressure and hemodynamic variability in hypertensive rats

Our previous studies have demonstrated that acute ethanol administration counteracts imidazoline I(1) receptor but not alpha(2)-adrenoceptor-mediated hypotension in spontaneously hypertensive rats (SHR). In the present study, we investigated the effect of chronic ethanol administration on hypotensive responses elicited by acute administration of selective imidazoline I(1) receptor (rilmenidine) or alpha(2)-adrenoceptor (alpha-methyldopa) agonist along with ethanol effects on: (i) locomotor activity and (ii) time-domain indices of variability in blood pressure (standard deviation of mean arterial pressure) and heart rate (standard deviation of beat-to-beat intervals and root mean square of successive differences in R-R intervals). Hemodynamic and locomotor responses elicited by rilmenidine or alpha-methyldopa were assessed in radiotelemetered ethanol-fed (2.5% or 5% w/v, 12 week) and control SHR. In control SHR, i.p. rilmenidine (600 microg/kg) or alpha-methyldopa (100 mg/kg) significantly reduced blood pressure. Rilmenidine had no effect on heart rate whereas alpha-methyldopa elicited a biphasic response (tachycardia followed by bradycardia). Blood pressure and heart rate oscillations were also reduced by both drugs, which may conform to sympathoinhibition. The hypotensive effect of rilmenidine or alpha-methyldopa was significantly attenuated by ethanol feeding (2.5% or 5%) in a concentration-dependent manner. In addition, ethanol attenuated alpha-methyldopa-evoked reduction in heart rate, but not blood pressure, variability in marked contrast to attenuating rilmenidine-evoked reductions in blood pressure, but not heart rate, variability. These findings demonstrate that, unlike its acute effects, chronic ethanol attenuates both imidazoline I(1) receptor and alpha(2)-adrenoceptor-mediated hypotension whereas its effect on hemodynamic variability depended on the nature of the hypotensive stimulus.

Effects of Alcohol Withdrawal on 24 Hour Ambulatory Blood Pressure Among Alcohol-Dependent Patients

BACKGROUND

Although epidemiologic studies have reported an association between alcohol intake and high blood pressure (BP), the results of intervention studies have shown inconsistent results. We embarked on a study to determine whether different subgroups of alcohol-dependent patients may be identified in relation to the effect of alcohol on BP.

METHODS

Fifty alcohol-dependent men (mean age, 41.4 years) received 0.4 g of ethanol per kilogram of body weight every 4 hr in 200 ml of orange juice during 24 hr and the same amount of orange juice without ethanol during another 24 hr. Twenty-four hour ambulatory BP monitoring was performed during ethanol and orange juice intakes, as was hormonal and biochemical analysis.

RESULTS

Thirty-five (75%) alcohol-dependent men were normotensive and 15 (30%) hypertensive. Eighteen (51%) normotensive and 12 (80%) hypertensive subjects showed a significant decrease in 24 hr mean BP after ethanol withdrawal (mean decrease of 8.4 mm Hg [95% confidence interval, -11.2 to -5.7] and 12.5 mm Hg [confidence interval, -16.2 to -8.8], respectively) and were considered as sensitive to alcohol. The remaining alcohol-dependent subjects were considered as resistant to alcohol. Normotensive subjects sensitive to ethanol showed a significantly greater left ventricular mass and a significantly lower ejection fraction than those normotensive patients whose BP did not change after ethanol withdrawal (both p < 0.01).

CONCLUSIONS

More than three fourths of the hypertensive and more than half of the normotensive alcohol-dependent patients showed sensitivity to the pressor effects of ethanol. Impairment also was observed in heart function in normotensive patients sensitive to the pressor effects of ethanol.

Effects of chronic ethanol feeding on clonidine-evoked reductions in blood pressure, heart rate, and their variability: time-domain analyses

The effects of chronic ethanol administration on the acute hemodynamic effects of clonidine were investigated in conscious radiotelemetered spontaneously hypertensive rats (SHRs). Changes evoked by clonidine (30 micro g/kg i.p.) in blood pressure, heart rate, and their variability were evaluated in ethanol [2.5 or 5% (w/v), 12 weeks] and pair-fed control rats. The blood pressure variability was determined as the standard deviation of the mean arterial pressure (SDMAP). Two heart rate variability indices were used, the standard deviation of beat-to-beat intervals (SDRR) and the root mean square of successive beat-to-beat differences in R-R interval durations (rMSSD). Compared with control rats, ethanol (2.5 and 5%)-fed rats exhibited concentration-related reductions in mean arterial pressure (MAP) and SDMAP versus no change in heart rate variability. In control rats, clonidine caused a significant reduction in MAP that continued for at least 5 h and was associated with significant reductions in SDMAP, SDRR, and rMSSD, responses that are consistent with the inhibition of central sympathetic tone. The hypotensive effect of clonidine was attenuated by ethanol in a concentration-related manner. The maximum reductions in MAP elicited by clonidine in ethanol (2.5 and 5%)-fed rats amounted to -23.4 +/- 2.8 and -15.1 +/- 1.5 mm Hg, respectively, compared with -35.4 +/- 1.2 mm Hg in control rats. The clonidine-induced reductions in SDMAP, SDRR, and rMSSD were also significantly attenuated by ethanol. These findings suggest that the attenuation of MAP and heart rate variability responses elicited by clonidine in ethanol-fed SHRs reflects alterations in the sympathovagal balance, which may be implicated in the antagonistic hemodynamic interaction between the two drugs.

Role of endothelial adenosine receptor-mediated vasorelaxation in ethanol-induced hypotension in hypertensive rats

Our previous findings showed that chronic ethanol feeding lowers blood pressure in spontaneously hypertensive rats. The present study investigated the role of the adenosine receptor-endothelial nitric oxide (NO) pathway in the hypotensive response to ethanol. Changes in blood pressure were evaluated in radiotelemetered pair-fed rats receiving liquid diet with or without ethanol (2.5% or 5%, w/v) for 12 weeks. The vasorelaxant activity of the adenosine analogue 5'-N-ethylcarboxamidoadenosine (NECA) in isolated aortic rings obtained from ethanol and control rats were evaluated. Ethanol (2.5% and 5%) lowered blood pressure in a dose-dependent manner. The hypotension started at week 1, reached its maximum at week 4 and remained so thereafter. In aortas with intact endothelium, NECA (10(-10) to 10(-4) M) produced a concentration-dependent relaxation of the phenylephrine-precontracted aortas. Compared with control rats, ethanol (2.5% and 5%) caused significant and concentration-related increases in NECA responses. This effect of ethanol was attenuated by the adenosine receptor antagonist 8-sulfophenyltheophylline and the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA). Further, endothelium denudation abolished the ethanol-evoked enhancement of NECA responses. The vasorelaxant responses to acetylcholine or sodium nitroprusside in aortic rings were not influenced by ethanol. In conclusion, the present findings suggest that chronic ethanol enhances the NO-dependent vasorelaxant responses to adenosine receptor activation and this may explain, at least partly, the mechanism of the hypotensive effect of ethanol in spontaneously hypertensive rats.

Alcohol and cardiovascular diseases: a historical overview

Studying its history generally provides insights relevant to current understanding of a subject: the health effects of alcohol consumption is no exception to this rule. Perceiving past errors in the hopes of avoiding their repetition is crucial. Because there are clear disparities in the relationships of alcohol drinking to various cardiovascular conditions, attempts to simplify the subject of alcohol and cardiovascular diseases have delayed understanding this area. Thus, the following are considered separately: cardiomyopathy, arsenic and cobalt beer-drinkers' disease, cardiovascular beri-beri, systemic hypertension, cardiac arrhythmias, stroke, atherosclerotic coronary heart disease (CHD), total mortality, and definitions of safe drinking limits. The basic disparity underlying all alcohol-health relations is between effects of lighter and heavier drinking.

Nutritional factors in the control of blood pressure and hypertension

Differing hypertension prevalence rates between certain population and age groups are partially due to differences in the intake of certain nutrients. Blood pressure is positively associated with higher sodium, alcohol, and protein intakes; it is inversely associated with potassium, calcium, and magnesium intakes. Salt may lead to an increase in blood pressure in the presence of salt sensitivity, but there is no inexpensive or easy strategy to identify salt-sensitive patients. Other risk factors for hypertension include obesity and lack of regular physical activity. The best strategy appears to be moderate salt restriction (6-7 g/day) in combination with an optimal compliance of the antihypertensive drug therapy, as well as adoption of the combination diet of the DASH study--a diet rich in fruits and vegetables, and thus rich in potassium. Current evidence does not support the increased intake of Ca2+ or Mg2+ for blood-pressure-lowering purposes only; however, calcium and magnesium may represent important components in the combination diet of the DASH study. It seems that it is the combination of these nutrients that is of crucial importance for the achievement of optimal blood-pressure reduction. Also recommended is a decrease in alcohol consumption and an increase in regular physical activity. Instead of a severe intervention with regard to 1 risk factor alone, positive changes in 5 habits combined--high salt intake, high sodium-to-potassium ratio, alcohol intake, calorie imbalance, and a sedentary life--may be the most realistic and effective strategy to counteract the present hypertension epidemic.

Effects of alcohol reduction on blood pressure: a meta-analysis of randomized controlled trials

Alcohol drinking has been associated with increased blood pressure in epidemiological studies. We conducted a meta-analysis of randomized controlled trials to assess the effects of alcohol reduction on blood pressure. We included 15 randomized control trials (total of 2234 participants) published before June 1999 in which alcohol reduction was the only intervention difference between active and control treatment groups. Using a standard protocol, information on sample size, participant characteristics, study design, intervention methods, duration, and treatment results was abstracted independently by 3 investigators. By means of a fixed-effects model, findings from individual trials were pooled after results for each trial were weighted by the inverse of its variance. Overall, alcohol reduction was associated with a significant reduction in mean (95% confidence interval) systolic and diastolic blood pressures of -3.31 mm Hg (-2.52 to -4.10 mm Hg) and -2.04 mm Hg (-1.49 to -2.58 mm Hg), respectively. A dose-response relationship was observed between mean percentage of alcohol reduction and mean blood pressure reduction. Effects of intervention were enhanced in those with higher baseline blood pressure. Our study suggests that alcohol reduction should be recommended as an important component of lifestyle modification for the prevention and treatment of hypertension among heavy drinkers.