Alcohol and 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 We also contacted authors of relevant articles regarding further published and unpublished work.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.

An Analysis of Anthropometric Indicators and Modifiable Lifestyle Parameters Associated with Hypertensive Nephropathy

The surge in prevalence of chronic noncommunicable diseases like hypertension and chronic kidney disease has been linked with modifiable lifestyle practices and increased body fat. This study sought to compare the association between different modifiable lifestyle practices, adiposity indices, renal function parameters, and hypertension as well as the predictive implications for levels of these parameters in target cardiac organ damage among an urban Ghanaian hypertensive population. Using a hospital-based case-control study design, 241 Ghanaian indigenes from the Kumasi metropolis were recruited for this study. The case group was made up of 180 hypertensives and 61 normotensives served as controls. In addition to sociodemographic data, standard haemodynamic, anthropometric, renal function, and cardiac organ damage assessments were done. The prevalence of chronic kidney disease (CKD) ranged from 13.3% to 16.6% depending on the equation used in estimating the glomerular filtration rate (eGFR). Percentage cluster distribution by chronic kidney disease was observed to be significantly tilted toward the upper quartiles (3rd and 4th) of the haemodynamic parameters measured. Chronic kidney disease was significantly higher among self-reported smokers and alcoholic hypertensives. In this urban population, adiposity was associated with hypertension and renal insufficiency. Chronic kidney disease was associated with hypertension and cardiac abnormalities.

The relation between different dimensions of alcohol consumption and burden of disease: an overview

AIMS

As part of a larger study to estimate the global burden of disease and injury attributable to alcohol: to evaluate the evidence for a causal impact of average volume of alcohol consumption and pattern of drinking on diseases and injuries; to quantify relationships identified as causal based on published meta-analyses; to separate the impact on mortality versus morbidity where possible; and to assess the impact of the quality of alcohol on burden of disease.

METHODS

Systematic literature reviews were used to identify alcohol-related diseases, birth complications and injuries using standard epidemiological criteria to determine causality. The extent of the risk relations was taken from meta-analyses.

RESULTS

Evidence of a causal impact of average volume of alcohol consumption was found for the following major diseases: tuberculosis, mouth, nasopharynx, other pharynx and oropharynx cancer, oesophageal cancer, colon and rectum cancer, liver cancer, female breast cancer, diabetes mellitus, alcohol use disorders, unipolar depressive disorders, epilepsy, hypertensive heart disease, ischaemic heart disease (IHD), ischaemic and haemorrhagic stroke, conduction disorders and other dysrhythmias, lower respiratory infections (pneumonia), cirrhosis of the liver, preterm birth complications and fetal alcohol syndrome. Dose-response relationships could be quantified for all disease categories except for depressive disorders, with the relative risk increasing with increased level of alcohol consumption for most diseases. Both average volume and drinking pattern were linked causally to IHD, fetal alcohol syndrome and unintentional and intentional injuries. For IHD, ischaemic stroke and diabetes mellitus beneficial effects were observed for patterns of light to moderate drinking without heavy drinking occasions (as defined by 60+ g pure alcohol per day). For several disease and injury categories, the effects were stronger on mortality compared to morbidity. There was insufficient evidence to establish whether quality of alcohol had a major impact on disease burden.

CONCLUSIONS

Overall, these findings indicate that alcohol impacts many disease outcomes causally, both chronic and acute, and injuries. In addition, a pattern of heavy episodic drinking increases risk for some disease and all injury outcomes. Future studies need to address a number of methodological issues, especially the differential role of average volume versus drinking pattern, in order to obtain more accurate risk estimates and to understand more clearly the nature of alcohol-disease relationships.

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.

Interaction of alcohol and an alpha1-blocker on ambulatory blood pressure in patients with essential hypertension

Ingestion of alcohol acutely decreases vascular resistance and blood pressure (BP) with activation of the sympathetic nervous system in Orientals. Although alpha1-blockers are widely used in the treatment of hypertension, the possible interaction between alcohol and alpha1-blockers has not been clarified. We examined the effects of prazosin on the alcohol-induced BP changes in Japanese men with mild hypertension. Ten hypertensive patients (54 +/- 3 years, mean +/- SE) were given 1 mL/kg of alcohol or isocaloric control drink with a light meal in the evening before and 5 to 7 days after treatment with prazosin (1 mg three times daily). Ambulatory BP monitoring was carried out every 30 min for 24 h in each period using Colin ABPM-630. Blood samples were obtained before and 2 h after intake of alcohol or control drink. Before prazosin treatment, alcohol ingestion decreased BP for several hours with a significant reduction in average 24-h BP, whereas it increased heart rate, plasma norepinephrine, and plasma renin activity. Treatment with prazosin caused a significant decrease in 24-h BP (136.3 +/- 4.0/82.8 +/- 2.5 v 131.6 +/- 3.2/80.0 +/- 2.3 mm Hg). The alcohol-induced hypotension at 2-4 h after ingestion was enhanced by prazosin (-18.0 +/- 3.7/-11.8 +/- 2.7 v -24.4 +/- 4.9/-17.8 +/- 2.8 mm Hg, P < .05 for diastolic BP). These results suggested that inhibition of the sympathetic nervous system with alpha1-blockers accentuates alcohol-induced hypotension. Ingestion of alcohol may cause a marked BP reduction in hypertensive Orientals treated with alpha1-blockers.

Effect of chronic ethanol consumption on the atrial natriuretic system of spontaneously hypertensive rats

There is a lot of discussion on the effects of ethanol (ETOH) on blood pressure (BP). It has been suggested that chronic moderate ETOH consumption prevents the development of age-dependent hypertension in humans and spontaneously hypertensive rats (SHR). However, the mechanism mediating this effect is unknown. In the present studies, we hypothesized the implication of atrial natriuretic peptide (ANP), a BP-lowering hormone, on the antihypertensive effect of moderate ETOH consumption. A 20% v/v solution of alcohol was given as drinking fluid to SHR and normotensive Wistar-Kyoto (WKY) rats for up to 32 weeks. This treatment prevented, at least in part, the age-dependent increase of BP in SHR and WKY rats. The lower BP was associated with significantly lower levels of circulating atrial natriuretic peptide in both groups. After chronic ETOH administration, total ANP content and concentration were higher in the left and right atria of SHR and WKY rats than in water-treated controls. Despite the ETOH-induced increase in atrial ANP content, there was no significant change in atrial ANP mRNA, suggesting decreased atrial release. Chronic ETOH treatment significantly reduced ANP mRNA in the ventricles of SHR but not of WKY rats. Correspondingly, ventricular ANP content and concentration were lowered by ETOH in SHR only. Chronic ETOH administration induced a significant increase of plasma arginine vasopressin and a significant decrease of plasma aldosterone in SHR but not in WKY rats. Thus, chronic ETOH treatment prevented the age-dependent elevation of BP in both SHR and WKY rats and altered the activity of heart ANP as well as of the aldosterone and plasma arginine vasopressin systems.

Alcohol and hypertension

Epidemiologic studies in the past two decades have firmly established a relationship between regular, heavier alcohol consumption and hypertension. This association has been demonstrated in both cross-sectional and prospective studies. It is found in both sexes and several races and is independent of the type of alcoholic beverage, adiposity, education, smoking, salt intake, and several other traits. Clinical experiments show that blood pressure falls in days to weeks with abstinence from alcohol and that it rises again within days after resuming drinking. No mechanism has been demonstrated for this alcohol/blood pressure effect. Alcohol withdrawal symptoms have not been seen in the clinical experiments; thus, this is not likely to be the major explanation. Studies of the role of alcohol in hypertension sequelae, such as coronary heart disease and stroke, have been difficult because of the effects of alcohol, independent of blood pressure, in these conditions. Overall, it is likely that this alcohol-hypertension relation is causal. Restriction of intake by heavier drinkers lowers blood pressure in some, and heavy alcohol ingestion should always be considered by clinicians as a possible hypertension risk factor.

Role of magnesium and calcium in alcohol-induced hypertension and strokes as probed by in vivo television microscopy, digital image microscopy, optical spectroscopy, 31P-NMR, spectroscopy and a unique magnesium ion-selective electrode

It is not known why alcohol ingestion poses a risk for development of hypertension, stroke and sudden death. Of all drugs, which result in body depletion of magnesium (Mg), alcohol is now known to be the most notorious cause of Mg-wasting. Recent data obtained through the use of biophysical (and noninvasive) technology suggest that alcohol may induce hypertension, stroke, and sudden death via its effects on intracellular free Mg2+ ([Mg2+]i), which in turn alter cellular and subcellular bioenergetics and promote calcium ion (Ca2+) overload. Evidence is reviewed that demonstrates that the dietary intake of Mg modulates the hypertensive actions of alcohol. Experiments with intact rats indicates that chronic ethanol ingestion results in both structural and hemodynamic alterations in the microcirculation, which, in themselves, could account for increased vascular resistance. Chronic ethanol increases the reactivity of intact microvessels to vasoconstrictors and results in decreased reactivity to vasodilators. Chronic ethanol ingestion clearly results in vascular smooth muscle cells that exhibit a progressive increase in exchangeable and cellular Ca2+ concomitant with a progressive reduction in Mg content. Use of 31P-NMR spectroscopy coupled with optical-backscatter reflectance spectroscopy revealed that acute ethanol administration to rats results in dose-dependent deficits in phosphocreatine (PCr), the [PCr]/[ATP] ratio, intracellular pH (pHi), oxyhemoglobin, and the mitochondrial level of oxidized cytochrome oxidase aa3 concomitant with a rise in brain-blood volume and inorganic phosphate. Temporal studies performed in vivo, on the intact brain, indicate that [Mg2+]i is depleted before any of the bioenergetic changes. Pretreatment of animals with Mg2+ prevents ethanol from inducing stroke and prevents all of the adverse bioenergetic changes from taking place. Use of quantitative digital imaging microscopy, and mag-fura-2, on single-cultured canine cerebral vascular smooth muscle, human endothelial, and rat astrocyte cells reveals that alcohol induces rapid concentration-dependent depletion of [Mg2+]i. These cellular deficits in [Mg2+]i seem to precipitate cellular and subcellular disturbances in cytoplasmic and mitochondrial bioenergetic pathways leading to Ca2+ overload and ischemia. A role for ethanol-induced alterations in [Mg2+]i should also be considered in the well-known behavioral actions of alcohol.

Alcohol, hypertension and cardiovascular disease--implications for management

Regular alcohol consumption raises blood pressure and in drinking populations contributes significantly to the prevalence of hypertension. The effect of alcohol is additive to that of obesity. Reduction in alcohol intake leads to a lowering of blood pressure over 1-4 weeks. Acute alcohol ingestion in the evening may lower blood pressures overnight. Heavy weekend drinking may lead to a pressor effect for the succeeding 3 to 4 days. Certain personality types or heavy job strain increase susceptibility to pressor effects of alcohol. Alcohol consumption in the range of 1-3 standard drinks a day appears to have a protective effect against coronary disease and ischaemic stroke, which may be greater in those with a higher risk of vascular disease. At higher levels of consumption the risks of haemorrhagic stroke, cardiomyopathy and hypertension deaths predominate. Moderation of alcohol consumption to no more than two standard drinks a day can be an effective means of improving blood pressure control reducing drug requirements in treated hypertensives, and avoiding drugs in mild hypertensives. Moderating alcohol and reducing excess weight have additive effects in reducing overall cardiovascular risk.