Alcohol and hypertension

The roles of alcohol in the epidemiology of cardiovascular diseases

Alcohol, both alone and in concert with deficiencies or excesses of other substances, can produce cardiomyopathy. In addition, alcohol can directly affect the cardiac conduction system and produce arrhythmias. Alcohol also affects known risk factors for stroke and coronary heart disease (CHD). Alcohol increases blood pressure, which may lead to hypertension and thus increase the risk of stroke. HDL cholesterol, which is inversely related to CHD risk, increases with alcohol, and LDL cholesterol, which is positively related to CHD risk, may decrease with alcohol, a potentially dually protective effect. However, both case-control and population based studies indicate only moderate levels of consumption, defined as two drinks per day or less, may be of benefit. Preliminary data from the Lipid Research Clinics Follow-up Study suggest that the beneficial effect of moderate amounts of alcohol may be mediated in part by increased HDL cholesterol and in part by another factor, possibly reduced coagulation. Clinical and laboratory data, in addition to epidemiologic data, suggest alcohol intake above two drinks per day leads to excess cardiovascular disease (CVD), probably reflecting hypercoagulability as well as hypertension at higher levels of intake. Because alcohol can lead to excess morbidity and mortality from CVD as well as several other diseases and conditions, public health policy should continue to discourage the drinking of alcohol, especially non-moderate consumption.

Hypertension, levels of serum gamma glutamyl transpeptidase and degree of blood pressure control in middle-aged males

Among the first screened 2439 males born in 1926 and 1927, aged 48-49 years at the time of screening and representing 76% of these age cohorts, uncontrolled or partly controlled hypertension was found in 7.5%. Of these individuals, 30% preferred to remain with their physicians, regardless of the degree of control they had achieved. Among those who were referred to the Hypertension Unit (5.2% of the screened population), elevated S-GT levels (greater than or equal to 1.10 mukat/l) were found in 38.3%, against 18.5% in the two cohorts. During 24 months of treatment and follow-up only two men among the entire group of hypertensives referred dropped out, both were heavy drinkers (greater than 80 g alcohol daily). The mean BP after treatment was significantly lower among men with normal than high S-GT values or in those who admitted to heavy drinking. Of the 99 males treated for more than two years, 82 (83%) were responders (supine DBP less than or equal to 95 mmHg). Of the non-responders, 70% were either heavy drinkers or had abnormal S-GT values. The possible role of alcohol in the pathogenesis of essential hypertension in middle-aged males is discussed.

High diastolic blood pressure: common among women who are heavy drinkers

The present study evaluates the relationship of different alcohol consumption levels to blood pressure among women. Blood pressure values were compared between four groups of women consuming different amounts of alcohol. Three groups were formed from the middle-aged female population participating in a health survey (n = 219): 15 consecutive alcohol abstainers, 136 consecutive moderate drinkers, and 68 consecutive heavy drinkers. Also, 78 consecutive female alcoholics reporting for treatment were included, forming the fourth group. The prevalence of systolic blood pressure > or = 160 mm Hg did not increase in relation to alcohol consumption. In contrast, the percentage of women showing diastolic blood pressure > or = 90 mm Hg clearly increased (p = 0.004) from abstainers (7%) to moderate drinkers (18%), to heavy drinkers (32%), and to alcoholics (37%). The highest blood pressure values were found among heavy drinkers. Compared with abstainers, the mean difference in systolic blood pressure was -12 mm Hg, with a 95% confidence interval from -2 to -23 mm Hg. For diastolic blood pressure, the difference was -6 mm Hg with a 95% confidence interval from 1 to -13 mm Hg. Among alcoholics, the blood pressure values had returned essentially to normal after 4 days of abstinence. It is concluded that alcohol consumption increases both systolic and diastolic blood pressure values among women. However, only diastolic blood pressure values increase enough to be clinically significant. Moderately elevated diastolic blood pressure, combined with normal systolic blood pressure, might thus be a possible sign of alcohol abuse among women. Abstinence should be emphasized as an inexpensive and rapidly effective treatment for mild hypertension among female alcohol abusers.

Alcohol, hypertension, coronary disease and stroke

1. The association between alcohol and hypertension has been recognized for several years. 2. However, it remains a paradox that if alcohol does cause hypertension there is little convincing evidence that alcohol is related to the cardiovascular complications of hypertension such as strokes and heart attacks. The relationship between alcohol and strokes remains inconclusive and there is evidence that moderate alcohol consumption may be protective against heart attacks. 3. It is possible, therefore, that alcohol does not so much cause hypertension, but rather a rapidly reversible rise in blood pressure which does not cause cardiovascular damage. When managing hypertensive patients, however, relevant counselling can bring about a useful fall in blood pressure.

Alcohol and coronary artery disease

Alcohol affects the heart and circulation in several ways. Chronic alcohol consumption can be associated with a variety of cardiovascular disorders, ranging from hypertension and stroke to heart failure and sudden death. At the same time an inverse correlation has been found between moderate drinking and incidence of coronary artery disease, perhaps due to its favourable effects on lipoprotein levels. Reports on acute effects of alcohol on coronary circulation, which may be of great significance in patients with pre-existing heart disease, have been contradictory. However, clinical studies have demonstrated an adverse effect of acute alcohol intake in low to moderate doses on coronary supply-demand relation in patients with angina pectoris. Considering the overall health hazard of alcohol consumption, a recommendation that patients increase their alcohol intake or that they start to drink if they do not already would probably be unjustifiable.

Ethanol affects sympathetic cotransmission and endothelium-dependent relaxation in the rat

The influence of ethanol on sympathetic nerve-mediated contractions of rat tail arteries and on endothelium-dependent relaxation of rat mesenteric arteries by acetylcholine was examined using the method of in vitro pharmacology. Ethanol potentiated sympathetic nerve-mediated contractions. Ethanol had no effect on the neurogenic contractions that remained after alpha-adrenoceptor blockade by prazosin. However, after P2x-purinoceptor desensitisation, the residual nerve-mediated contractions were significantly enhanced by ethanol. Contractions to exogenous noradrenaline and alpha,beta-methylene ATP were unaffected by ethanol. It is concluded that ethanol selectively potentiates the noradrenergic component of sympathetic neurotransmission. Ethanol depressed the relaxation by acetylcholine but not that induced by sodium nitroprusside. These results indicate that ethanol can affect both the neural and endothelial control of vascular tone. The potentiated noradrenergic vasoconstrictor response to sympathetic nerve stimulation and the compromised capacity of the endothelium to cause relaxation after ethanol treatment may contribute to the development of vascular diseases associated with alcohol consumption.

Alcohol consumption and ultrasonographically assessed carotid artery wall thickness and distensibility. The Atherosclerosis Risk in Communities (ARIC) Study Investigators

BACKGROUND

Although much has been written in recent years about the relation between alcohol and atherosclerotic disease, controversy exists as to whether and how alcohol exerts an effect on atherosclerosis in different sites.

METHODS AND RESULTS

We tested the hypothesis that alcohol consumption is associated inversely with carotid atherosclerosis in a population sample of 45- to 64-year-old men and women who participated in the Atherosclerosis Risk in Communities (ARIC) Study and were free of cardiovascular disease at a baseline examination in 1987 to 1989. B-mode ultrasonography was used to determine carotid artery intimal-medial wall thickness and distensibility as indices of the degree of atherosclerosis. The level of alcohol consumption in the ARIC sample was generally low. Age-adjusted mean values of alcohol consumed (grams per week) were 72.0 for white and 74.3 for nonwhite men and 24.8 for white and 11.2 for nonwhite women. After adjustments for age, artery depth, education, body mass index, sport index, cigarette-years of smoking, low-density lipoprotein cholesterol, and diabetes mellitus, there was no significant cross-sectional association of reported current alcohol intake with either carotid artery wall thickness (among white and nonwhite men and nonwhite women) or distensibility (in any of the four sex-race groups). Among white women, the adjusted mean value of carotid artery wall thickness tended to be higher in light to moderate drinkers than in never or rare drinkers, but the difference across drinking status categories was of borderline statistical significance (P = .04) and may be of little biological importance.

CONCLUSIONS

The ARIC Study found no material cross-sectional association between current alcohol intake and carotid atherosclerosis but provides an opportunity in the future to study atherosclerosis progression and incident events in relation to alcohol consumption in a large population sample of men and women.

Predictors of carotid stenosis in older adults with and without isolated systolic hypertension

BACKGROUND AND PURPOSE

This study was designed to determine the prevalence of carotid stenosis and atherosclerosis in older adults with and without isolated systolic hypertension and to determine risk factors for carotid artery disease in these two groups.

METHODS

Duplex scans were performed on 187 participants of the Systolic Hypertension in the Elderly Program and on 187 normotensive control subjects. Doppler measures of blood flow velocity were used to determine the prevalence of internal carotid artery stenosis.

RESULTS

Carotid stenosis was found in 25% of hypertensive participants but in only 7% of normotensive participants (p < 0.001). Among hypertensive participants, carotid stenosis was correlated with lower diastolic blood pressure (p = 0.022). In multivariate analysis, systolic blood pressure of > or = 160 mm Hg was the strongest predictor of carotid stenosis. Other variables independently related to stenosis were diastolic blood pressure of < 75 mm Hg (p = 0.001), alcohol use (p = 0.005), heart rate of > or = 80 beats per minute (p = 0.013), smoking (p = 0.034), high concentration of apoprotein B (p = 0.001), and low concentration of high density lipoprotein cholesterol (borderline significant, p = 0.069). Among hypertensive participants, the strongest predictor of carotid stenosis was low diastolic blood pressure. This relation persisted even after taking into account differences in pulse pressure.

CONCLUSIONS

Isolated systolic hypertension is strongly correlated with carotid stenosis, and among those with isolated systolic hypertension low diastolic blood pressure is a marker for carotid stenosis.

Lipoproteins and blood pressure as biological pathways for effect of moderate alcohol consumption on coronary heart disease

BACKGROUND

Several epidemiological studies have shown light-to-moderate alcohol consumption to have a net protective effect on the incidence of coronary heart disease (CHD).

METHODS AND RESULTS

Major components of this effect, both positive and negative, may be explored using models that include both alcohol and variables expected to mediate the observed alcohol effect. Such modeling in a cohort of men of Japanese descent followed in the Honolulu Heart Program indicates that about half of the observed protection against CHD afforded by moderate alcohol consumption is mediated by an increase in high density lipoprotein cholesterol. An additional 18% of this protection is attributable to a decrease in low density lipoprotein cholesterol, but it is counterbalanced by a 17% increase in risk due to increased systolic blood pressure. The explanation for the residual 50% benefit attributable to alcohol is unknown but may include interference with thrombosis. The results in this population replicate those in the Lipid Research Clinics cohort studied earlier with the same analytic technique.

CONCLUSIONS

The consistency of these findings across populations, along with the demonstration of reasonable biological pathways for this effect of alcohol, provides strong support for the hypothesis that light-to-moderate alcohol intake is protective against heart disease in men.

Alcohol effects on the morphometric development of the subfornical organ and area postrema of the albino mouse

We have studied the development of the nuclear sizes of ependymocytes and neurons of two circumventricular organs of the male alcoholic mouse: the Subfornical Organ (SFO) and the Area Postrema (AP), comparing the results with a control group. The global volume of both centers was also studied. The results show that the SFO, a structure related to the control of fluid balance, responds to alcoholism with an increase of the global volume. This increase could be related to the variations of salt-water balance and/or blood pressure in chronic alcoholism. However, the size of cell nuclei in the SFO is not affected. In contrast, the AP responds to chronic alcoholism like other nervous centres, with a decrease of the nuclear size of its cells. The global volume of AP does not change.

Dietary alcohol, calcium, and potassium. Independent and combined effects on blood pressure

To determine whether or not the previously reported association between alcohol intake and high blood pressure is influenced by differential intake of calcium and potassium in drinkers compared with nondrinkers and to assess the magnitude of the independent contributions of alcohol, calcium, and potassium to blood pressure, these associations were evaluated in 7,011 men of Japanese descent. Categorical analyses and multiple linear regression techniques were used to test the hypotheses that alcohol, calcium, and potassium were independent predictors of blood pressure. Alcohol consumption above a threshold of approximately 20 ml/day was found to be positively, strongly, and independently correlated with systolic and diastolic pressures, and this effect was completely independent of the effects of calcium and potassium. Calcium and potassium intake were highly correlated (r = 0.59) and were inversely related to blood pressure, and their combined effect was greater than the effect of either alone. However, in the subgroup of moderate and heavier drinkers, only potassium was inversely related to blood pressure. This finding is compatible with previous reports of malabsorption and increased excretion of calcium at higher levels of alcohol intake, and it indicates that a small portion of the alcohol-induced blood pressure elevation may be mediated through calcium depletion. In the range of dietary intake in this cohort, the effect of alcohol on blood pressure was stronger than was either the separate or combined effects of calcium and potassium.

Pharmacokinetic interaction between indoramin and ethanol

1. The effect of ethanol consumption (0.5 g/kg) on the pharmacokinetics of the alpha adrenoceptor antagonist indoramin, administered orally (50 mg) or intravenously (0.175 mg/kg) has been investigated in young volunteers. Sedation was also assessed using a visual analogue scale. 2. After oral indoramin administration, ethanol caused increases of 58% (P less than 0.01) in Cpmax, and 25% (P less than 0.05) in AUC. There was no effect of alcohol on elimination half-life. The combination of ethanol and indoramin was more sedative than indoramin alone. 3. Ethanol did not alter the pharmacokinetics of an intravenous dose of indoramin. However indoramin caused a small but statistically significant increase (26%) in blood ethanol concentrations during the first 1.25 h after dosing. Both indoramin and ethanol caused sedation. 4. The increased bioavailability of oral indoramin in the presence of ethanol may reflect some enhanced absorption, but it is also consistent with inhibition of first-pass metabolism of a flow-limited drug. The clinical implications are discussed.

Relationship of dietary sodium, potassium, calcium, and magnesium with blood pressure. Belgian Interuniversity Research on Nutrition and Health

From 1979 through 1984, a randomized epidemiological survey in Belgium assessed the dietary intake of sodium, potassium, calcium, and magnesium using 24-hour food records checked by trained dietitians. Dietary cation intake levels were correlated with blood pressure both in the total group (4167 men and 3891 women) and in the group not taking antihypertensive medication (3814 men and 3329 women). Serum sodium, potassium, calcium, and phosphorus were also measured. Multiple regression analysis adjusting for age, body mass index, heart rate, alcohol intake, and total caloric intake revealed a significant positive correlation between sodium intake and blood pressure in the group not treated for hypertension except for diastolic blood pressure in women. A significant negative correlation was found between dietary calcium intake and diastolic blood pressure in men and between dietary magnesium intake and systolic blood pressure in women. No independent effect of dietary potassium intake on blood pressure could be established. Significant but weak correlations were found between the dietary intake of sodium, potassium and calcium and their serum values. The study confirms the hypothesis that at the population level dietary cations are related to the regulation of blood pressure.

Peripheral and cerebrovascular actions of ethanol, acetaldehyde, and acetate: relationship to divalent cations

Inasmuch as ethanol is thought to exert its major effects in the autonomic and central nervous systems, it is important to determine whether acute versus chronic ingestion of this abused substance exerts any direct actions on peripheral and cerebral blood vessels. Since the chronic effects of ethanol on the cardiovascular system appear to be pivotal in the etiology of hypertension, coronary heart disease, and strokelike events, it is important to elucidate and understand the effects of chronic ethanol abuse and its mechanism(s) of action on the peripheral and cerebral blood vessels. Data are reviewed which suggest that the peripheral vasodilation and hypotension which result from acute ingestion (or administration) of ethanol may, in large part, be a consequence of its direct actions on vascular smooth muscle cells, both at the macro- and microcirculatory levels. At least two mechanisms appear to contribute to this vasodilator effect: inhibition of the normal rhythm or vasomotion (spontaneous mechanical activity) of vascular smooth muscle, and depression of the contractile responses to endogenous neurohumoral substances that play a role in maintaining vascular tone and regulation of blood flow. The data acquired so far suggest that the dilator actions are related causally to interference with movement and/or translocation of Ca2+ across the vascular membranes. In addition, these actions appear to resemble the peripheral vascular effects of general anesthetics. Evidence is also reviewed which indicate that ethanol, in contrast to acting as a vasodilator in the splanchnic vasculature, is often a potent and concentration-dependent constrictor of arterioles and venules in the skeletal muscle vasculature. Direct in situ observations on the rat brain, using high resolution, quantitative TV image-intensification microscopy, indicates that administration of ethanol, irrespective of the route of administration (e.g., perivascularly, intraarterially, or systemically), produces graded concentration-dependent spasms of arterioles and venules. Concentrations of ethanol approximately equal to greater than 250 mg/dl produce intense spasms resulting in rupture of these vessels. Recent in situ studies in conscious dogs, using radiolabeled microspheres, also indicate that ethanol can produce deficits in regional brain blood flow. Studies with isolated canine middle cerebral and basilar arteries clearly demonstrate that low concentrations of ethanol (e.g., less than 10 mM) can produce concentration-dependent spasms by a direct vascular action.(ABSTRACT TRUNCATED AT 400 WORDS)

On the potential health effects of consuming "non-alcoholic" or "de-alcoholized" beverages

This paper reviews the potential health risks for persons who consume the newly available "non-alcoholic" or "de-alcoholized" beverages which may contain trace amounts of ethanol (less than 0.5% by volume). The discussion includes relative risk rates for chemical dependency, fetal alcohol syndrome, chemical and natural hypersensitivity, cancer, cardiomyopathy, hypertension and cirrhosis for those who drink standard alcoholic drinks and "non-alcoholic" drinks. It is concluded that non-alcoholic drinks pose little risk for developing alcohol related problems based on our current physiological and psychocultural knowledge.

Alcohol consumption, blood pressure, lipids, and cardiovascular mortality

Interest in the effects of alcohol on cardiovascular risk factors and disease has increased sharply with reports of complex and previously unsuspected associations. The present report focuses on the associations of alcohol with blood pressure, lipids, and cardiovascular disease mortality. The epidemiological evidence to date appears to support the idea that moderate alcohol consumption, defined as two drinks a day or less, may offer some protection for coronary heart disease, but that higher levels of alcohol promote hypertension and are directly toxic to the heart, leading to stroke, arrhythmias, cardiomyopathy, and perhaps even coronary heart disease.

The pressor and metabolic effects of alcohol in normotensive subjects

Changes in blood pressure, pulse rate, and plasma catecholamines, renin activity, cortisol, and calcium were studied in 16 normotensive subjects (eight with a family history of hypertension) for 5 hours following ingestion of alcohol-free and alcohol-loaded beer. Both systolic and diastolic blood pressure rose after alcohol consumption; maximum responses occurred at peak blood alcohol concentrations and were significantly higher than those seen after placebo. Pulse rate was also significantly higher after alcohol ingestion and continued to rise throughout the study. There was no difference in the pressor response to alcohol between the groups with and without a family history of hypertension. No difference was found in plasma norepinephrine or epinephrine levels between alcohol and placebo phases. However, subjects with no family history of hypertension had significantly higher plasma norepinephrine levels (p less than 0.01) than did those with a family history during both the alcohol and placebo phases, although baseline blood pressures were not significantly different. Plasma epinephrine level was similar in both groups. Plasma renin activity was unchanged throughout, but plasma cortisol fell during both phases. Plasma calcium showed a small but significant fall with alcohol consumption in both groups (p less than 0.001). These results indicate that in normotensive subjects alcohol ingestion causes a rise in systolic and diastolic blood pressure that is not influenced by a family history of hypertension. This effect does not appear to be sympathetically mediated but may be due to a direct vasoconstrictor effect of alcohol, possibly with an alcohol-induced shift in intracellular calcium.

Role of alcohol in clinical nephrology

Different nephrological derangements are observed in severe alcoholics. Until now the direct toxicity of ethanol is only shown in the fetal alcohol syndrome with various malformations of the genitourinary tract. In the adult the kidney is often involved in the development, maintenance and counterregulation of complex electrolyte disturbances like phosphate and potassium hypoglycemia etc. The alcohol associated retention of urate, induced by hyperlactatemia and/or increased beta-hydroxybutyrate concentration is only rarely complicated by urate nephropathy. Alcohol intoxication (acute and chronic) predisposes to rhabdomyolysis with the risk of acute renal failure. There are some hints that chronic alcoholism with myopathy increases the vulnerability of the kidney for further toxic agents. In rats glycerol induced renal failure is enhanced by alcohol pretreatment. Finally, regular alcohol consumption raises the blood pressure, which per se is a risk factor for renal damage.

Pressor effects of alcohol in normotensive and hypertensive subjects

The effects of acute alcohol consumption and abstinence on blood pressure were studied in normal healthy subjects and in non-drinking and regularly drinking hypertensive patients. All subjects drank alcohol (1 g/kg body weight daily) for 5 days then abstained for 5 days. There was no significant difference in blood pressure in normal subjects during and after alcohol ingestion. However, in hypertensive non-drinkers both systolic and diastolic pressures when standing were significantly higher during the period of alcohol intake; supine blood pressure was not significantly higher. In hypertensive patients who drank regularly, standing and supine systolic and diastolic blood pressures were significantly higher during the period of drinking.

Geographical and socioeconomic distribution of high blood pressure and borderline high blood pressure in a Swedish rural county

This report on "high" blood pressure (HBP) and "borderline high" blood pressure (BHBP) is based on a cross-sectional study in a rural Swedish county. The study was initiated in the Spring of 1977, selecting 7986 individuals aged 25-75 years, in 5-year intervals, in the 16 municipalities of Skaraborg County. A combination of health examination and a survey using polling of the population by interview was used. The blood pressure values that are presented are based on a casual measurement taken after a 5-minute rest period. The limits of HBP and BHBP correspond to the Swedish standard limits. Only a few researchers in Sweden have focused on the correlation between socioeconomic factors and hypertension. Moreover, few examinations have been made internationally concerning the correlation between socioeconomic factors and borderline hypertension. There was a significant variation in mean values of high blood pressure when comparing socioeconomic groups and comparing occupations. These differences associated with educational level were more pronounced for women than for men. Workers, especially men and persons with less formal education, had the highest mean blood pressure. Significant differences between socioeconomic groups existed even after adjustment for age, sex, weight index, smoking and treatment of hypertension. The socioeconomic differences constitute the most plausible explanation of differences seen between municipalities. "Borderline high" blood pressure was more prevalent than "high" blood pressure. Socioeconomic differences were greater within the borderline high blood pressure group than in the high blood pressure group. i.e., the differences between workers and civil servants were somewhat greater in the borderline high blood pressure group. Since there are socioeconomic differences, it might be possible to concentrate preventive activities in local communities on risk groups.

Alcohol consumption and cardiovascular risk factors

This chapter reviews epidemiologic evidence relating alcohol consumption to the cardiovascular risk factors of high-density lipoprotein (HDL)-cholesterol and blood pressure. Alcohol consumption shows a linear dose-response relationship with HDL-cholesterol that is independent of other known determinants of HDL-cholesterol. The effect of alcohol on HDL-cholesterol appears to be reversible. The relationship of alcohol consumption to HDL-cholesterol subfractions and to the HDL apoproteins is not clear. Alcohol consumption also shows a linear dose-response relationship with blood pressure. Although the association is consistent, the estimated effect of alcohol consumption on blood pressure is small. This effect of alcohol may also be reversible. No biological mechanisms have been established for these associations. Some of the effect of alcohol on the risk of coronary heart disease may be explained by the effects of alcohol on these risk factors. It remains to be determined if alcohol also exerts an effect that is independent of these risk factors.

Rat blood pressure during ethanol withdrawal

Hypertension appears to be a clinical sign of ethanol withdrawal. In an effort to see if hypertension is a general consequence of ethanol withdrawal, we have monitored blood pressure and heart rate in conscious rats during ethanol withdrawal. Sprague-Dawley rats were placed in Plexiglas chambers and exposed for 3 weeks to either ethanol vapor in air or to air alone. Blood ethanol levels in the ethanol treated group averaged 178 +/- 9 mg/dl during the last 2 weeks of ethanol exposure. Four to 18 hours prior to blood pressure measurement, rats were removed from the ethanol chambers, briefly anesthetized with halothane and implanted with an indwelling abdominal aortic cannula. Rats were either returned to the Plexiglas chambers and re-exposed to ethanol or air overnight or withdrawn from ethanol. Blood pressure and heart rate were then monitored at various periods from 5 hours to 4 days following the cessation of ethanol exposure. Analysis of variance revealed a significant decrease in blood pressure and heart rate in rats exposed to ethanol vapor as compared to controls. There was a significant negative correlation between the average blood ethanol levels, taken during ethanol exposure, and systolic blood pressure at 5 hours, 2 days and 3 days following cessation of ethanol exposure. These signs of hypotension and bradycardia indicate that hypertension is not a consequence of ethanol withdrawal in all animals.

Alcohol, the cerebral circulation and strokes

Inasmuch as ethanol is thought to exert its major effects on the CNS, it is important to determine whether this abused substance can exert any direct action on cerebral blood vessels. Since chronic ingestion of alcohol: (1) can produce a loss (and degeneration) of neurons and glial cells in the brain, and (2) is associated, often, with hallucinations in human subjects particularly those undergoing withdrawal, it is possible that ethanol could produce hypoxia in select regions of the brain. The available indirect evidence in man and animals, albeit equivocal, does indicate that ethanol in certain concentrations might produce deficits in cerebral blood flow in select regions of the brain. Direct in-situ observations on the rat brain, using high-resolution, quantitative TV image-intensification microscopy, indicates that administration of ethanol, irrespective of the route of administration (e.g., perivascularly, intraarterially or systemically), produces graded concentration-dependent spasms of arterioles and venules. Concentrations of ethanol approximately greater than 250 mg/dl produce intense spasms resulting in rupture of these vessels. Recent in-situ studies in conscious dogs, using radiolabelled microspheres, also indicate that ethanol can produce deficits in regional brain blood flow. Studies with isolated canine middle cerebral and basilar arteries clearly demonstrate that low concentrations of ethanol (e.g., (less than 10 mM) can produce concentration-dependent spasms by a direct vascular action. Collectively, these new findings could be used to support the concept that heavy use of alcohol or binge-drinking can produce stroke-like effects. Specific calcium antagonists prevented or reversed the alcohol-induced cerebrovasospasms in rats and may prove valuable in treating the hypertension and strokes observed in heavy users of alcohol.

Alcohol, hypertension, and stroke

The authors compared the drinking habits of stroke patients and controls who were matched for the variables of age, sex, race, and day of the week admitted to the hospital. Rates of alcoholism were similar in the two groups. However, stroke patients were more likely to be current drinkers than controls, and were more likely to have been drinking within 24 hr of admission to the hospital, most of them rather heavily. Among the stroke patients, alcoholism was associated with hypertension, with being a current drinker, and with drinking at index, i.e., within 24 hr of the first symptoms of stroke. Of those stroke patients who were drinking at index, there were significant associations with being black, alcoholic, and hypertensive. The implications of these findings are discussed.

The effects of alcohol on blood pressure and electrolytes

The interaction between alcohol abuse, changes in blood pressure, and electrolyte abnormalities is complex. Some effects of alcohol are seen only with acute ingestion, some during withdrawal, and some only in chronic drinkers. Careful attention to the interactions between the metabolism of various electrolytes can prevent unnecessary morbidity and mortality in alcoholic patients.

Elevated catecholamine levels in hypertension. Basis for misdiagnosis of pheochromocytoma in three patients

These three cases show that the laboratory diagnosis of pheochromocytoma, like that of other endocrine disorders, may be in error if the physiologic state of the patient is not taken into consideration. Each of these patients had a condition that enhanced catecholamine production--hypothyroidism in one case, volume depletion induced by use of diuretics in another, and alcoholism in the third. When these conditions were controlled, catecholamine values returned to normal.

Changes in the blood platelets of alcoholics during alcohol withdrawal

The effects of alcohol withdrawal on platelet count and platelet function was studied sequentially in a group of alcoholics. Baseline values for platelet count, platelet adenine nucleotides and plasma beta-thromboglobulin (beta TG) level were within the normal range but platelet aggregability (especially with ADP and adrenaline) and circulating platelet aggregates were decreased for the group as a whole. After alcohol withdrawal there was a pronounced increase in all parameters measured which reached statistical significance in many cases and persisted for two to four weeks. The potential implications and possible mechanisms for these changes are discussed.

Alcohol, tobacco, and hypertension

In many studies of diverse populations it has been found that persons drinking relatively large amounts of alcohol tend to have higher blood pressures. In the Kaiser-Permanente study of about 87,000 persons, this alcohol-blood pressure association was not attributable to demographic characteristics, adiposity, reported salt use, smoking, or coffee consumption, nor could it be explained by underreporting of alcohol consumption. If the relationship is a causal one, the pathogenesis is not yet established; direct mechanisms or the effects of withdrawal from alcohol are possible explanations. The Kaiser-Permanente data suggest that about 5% of hypertension in the general population may be due to the consumption of three or more alcoholic drinks per day. Alcohol use shows a positive relation to some sequelae of hypertension but not others; the outstanding exception is coronary heart disease which is negatively related to alcohol intake, probably through different mechanisms. In most studies, cigarette smokers have shown similar or slightly lower blood pressures than non smokers. The degree to which this is due to the thinner body build of smokers, on the average, is not well established; nor is the degree to which a stronger negative relation of smoking to blood pressure might be masked by concomitant alcohol use.

Blood pressure and alcohol intake in heart patients

The association between alcohol consumption and blood pressure has been studied in 2025 male and 282 female patients undergoing diagnostic coronary angiography. The increase in amount of alcohol consumed correlated with higher systolic and diastolic blood pressure; this effect was especially pronounced in men over 50 years of age. The association was less marked in male patients under 50 years old, in women, and in patients on antihypertensive medication. Readings in the range of definitive hypertension were more prevalent among older patients consuming six or more drinks daily than in abstainers of the same age group.

Alcohol-induced hypertension

Blood pressures of 132 alcoholic patients whose mean daily alcohol consumption exceeded 80 g where measured while drinking, during detoxification from alcohol, and after a period of abstinence. At the time of presentation blood pressure exceeded 140/90 in 51.5% of patients. There was a significant correlation between blood pressure and mean daily alcohol intake over the previous three months and also between the level of blood pressure and the severity of alcohol-withdrawal symptoms. There was no relation between blood pressure and degree of histological liver damage, but a correlation was found with serum gamma-glutamyl-transferase activity and with mean corpuscular volume. In most patients blood pressure fell to normal after detoxification, and remained so for at least a year in those who continued to abstain. However, blood pressure rose in those who started drinking again. Excessive alcohol consumption is an important and insufficiently recognised cause of hypertension and, although the exact mechanism is unknown, treatment is simple and effective if patients can be persuaded to abstain.U

Alcohol consumption and blood pressure. The lipid research clinics prevalence study

The relationship between alcohol consumption and systolic and diastolic blood pressure (BP) was examined in 2482 men and 2301 women 20 years of age or older in nine North American populations. Men at the highest level of alcohol consumption (greater than or equal to 30 ml alcohol per day) had the highest BP, while women either at the highest level of alcohol consumption or consuming no alcohol had the highest BP. Men aged greater than or equal to 35 years of age consuming greater than or equal to 30 ml alcohol per day were 1.5 to 2 times more likely to be hypertensive than non-drinkers. Multivariate analysis showed systolic and diastolic BP in both men and women to be positively and significantly (p less than 0.05) related to alcohol consumption, and this relationship was independent of the potential confounding effects of age, obesity, cigarette smoking, regular exercise, education, and gonadal hormone use in women. The regression coefficients indicated that an average of 30 ml of alcohol per day would produce a 2 to 6 mm Hg increase in systolic BP. Analyses suggested the univariate U-shaped alcohol-BP association in women was confounded by differences in obesity and cigarette smoking in nondrinking women, and by very low alcohol consumption in hypertensive women using medication. Additional analyses indicated that alcohol consumed in the 24 hours prior to the study was much more strongly associated with elevated BP than alcohol consumed in the week prior to the study excluding the previous 24 hours. We conclude that alcohol appears to have a modest but consistent and independent effect on systolic and diastolic BP.

Plasma noradrenaline concentration in hypertensive and normotensive forty-year-old individuals: relationship to plasma renin concentration

Forty-year-old individuals with labile and with mild sustained essential hypertension, identified during a survey of a population born in 1936, were investigated. None had ever received antihypertensive treatment. In thirty-three individuals (26 M, 7F) with diastolic blood pressure (DBP) greater than or equal to 95 mmHg at the very first examination and in thirty-one (14 M, 17 F) randomly selected normotensive controls plasma noradrenaline concentration (PNAC) was measured at rest supine. In twenty-two patients (16 M, 6 F), with sustained diastolic hypertension (diastolic blood pressure greater than or equal to 95 mmHg on at least three different occasions) and in twenty-four (14 M, 10 F) normotensive controls PNAC and plasma renin concentration (PRC) were measured supine at rest and again 2 h after furosemide and ambulation. Basal and acutely stimulated values for PNAC and PRC were identical in hypertensive and normotensive individuals. A close correlation between PNAC and PRC after acute stimulation (r = 0.77, P < 0.001) as well as between the absolute changes from resting to acutely stimulated values (r = 0.72, P < 0.001) were found in the hypertensive individuals. It is concluded that sympathetic nerve activity, as defined from measurements of plasma noradrenaline concentration, is similar in young patients with mild hypertension and in normotensive controls. We propose that the discrepancies found in the literature might be related to a lack of comparability between hypertensive and normotensive individuals studied, as far as the source of study populations is concerned.

Serum gamma-glutamyl transferase and a somatic health score in middle-aged men

In an ongoing population investigation of middle-aged men in Malmö, Sweden, several health screening variables showed strong but crude individual covariations with the level of the hepatic enzyme, serum gamma-glutamyl transferase (GGT). These variables were combined, according to an analysis of their normal distributions, into a score index which exhibited a much smoother correlation with low, normal, and elevated levels of GGT when tested in a random population subsample. It is concluded that this scoring system may find further utilisation as a general descriptive method of recording statistical covariations between health screening tests and sum them up.

Alcohol and mortality: the Honolulu Heart Study

It has been shown previously that coronary heart disease was less likely to develop in Japanese men in Honolulu who drank alcoholic beverages than in those who abstained, and that the more they drank (up to about 60 ml/day of ethanol) the lower the risk. In this report on the same men, it is shown that the same sort of relation holds for mortality from coronary heart disease but that the reverse is true for death from cancer and from stroke. Men who drank were more likely to die from these causes than those who abstained, and the more they drank the greater the risk of death. Men who drank relatively large amounts were more likely to die from cirrhosis of the liver than other men. The resultant curve for total mortality is u-shaped, the lowest risk being for men who consumed from 1 to 10 ml/day of ethanol. Even at that low level of consumption, however, the risk of death from cancer or stroke was greater than it was for nondrinkers. In short, for this population of Japanese men, alcohol consumption appears to have some benefits and some hazards with regard to mortality, and the benefit or hazard depends on which cause of death is being considered.