High blood pressure, alcohol and cardiovascular risk.

More than 50 prospective population or cross-sectional studies have established a close association between regular alcohol consumption and high blood pressure (BP), consistently showing a linear dose-response relationship starting with a consumption threshold of 3 drinks per day (30 g of ethanol) (1-2). However, men who consume 1-2 drinks per day and women who drink half of this amount do not show significant changes in BP (3) or even significant reductions in BP compared to abstainers (4), suggesting that the pressor effects of alcohol may follow a " J " shape curve (5). Several aspects of the data obtained from different studies suggest a causal relationship between high ethanol intake and an increase in BP. Thus, reduction of alcohol intake lowers BP, whereas continued intake impairs response to antihyper-tensive treatments. Intervention studies carried out in human subjects in order to confirm epidemiological data have shown inconsistent results with either an increase or a decrease in BP with alcohol administration, even when ambulatory BP monitoring (ABPM) was used for accurate measurement (6-7). These conflicting results may be due to differences in rate, dose, route of ethanol administration, time interval to BP pressure measurement, and, probably, psychic factors in the reported studies. However, a meta-analysis of randomized controlled trials, in which alcohol reduction was the only intervention difference between active and control treatment groups, showed a significant reduction in mean (95% confidence interval) systolic and diastolic BP of – 3.31 mm Hg (-2.52 to-4.10 mmHg) and-2.04 mmHg (-1.49 to 2.58 mmHg), respectively. These reductions in BP would be expected to result in a 6 % reduction in the risk of coronary heart disease, and a 15% reduction in the risk of stroke and transient ischemic attacks (8).