Introduction
Alcohol has complex effects on the cardiovascular system. The relationship between alcohol and hypertension is well known, and a restriction of alcohol intake is widely recommended as a part of lifestyle modifications in the management of hypertension.1, 2, 3, 4, 5, 6 Alcohol has both pressor and depressor actions, however, and the genetic susceptibility regarding alcohol metabolism influences the cardiovascular effect of alcohol.3, 7 The effect of alcohol on blood pressure [BP] is also modified by several factors, such as the level of consumption, time period after the last drink and overall drinking behavior.
Alcohol consumption is associated with several cardiovascular diseases, such as brain hemorrhage, heart failure and arrhythmia, as well as with other disorders.3, 8, 9, 10, 11 Heavy drinking and alcoholism not only lead to medical problems but are also serious social concerns. However, alcohol also seems to have beneficial effects, including the prevention of ischemic heart disease. It has been shown that cardiovascular and all-cause mortality is lower in light drinkers compared with nondrinkers.3, 8, 9, 10, 11, 12
The purpose of this article is to review physio-pathological effects of alcohol on cardiovascular and related systems and to describe its role in hypertension and cardiovascular disease. I will outline the cardiovascular actions of alcohol, the effects of alcohol on BP and hypertension, including changes in 24-h BP, and the relationship between alcohol and cardiovascular diseases.
Cardiovascular actions of alcohol
Acute effect on BP
The effect of a single intake of alcohol on BP in normal subjects is not consistent among studies. Some studies have shown an increase in BP,13, 14 whereas it decreased15, 16 or remained unchanged17, 18 in others. In hypertensive patients, the BP also became elevated19 or fell20 after a single ingestion of alcohol.
In studies showing the pressor effect of alcohol, a BP increase was observed within 1 h after drinking; however, the increase was not sustained.3 On the other hand, BP usually fell or remained unchanged after alcohol consumption in studies with prolonged observation periods. Stott et al.21 reported that BP levels increased at 1 h after drinking but tended to decrease over the next 7 h in normotensive subjects.
We examined the effect of a single intake of alcohol [1 ml kg−1] on BP using ambulatory BP monitoring [ABPM] in hypertensive Japanese men.7 As shown in Figure 1, the BP decreased and the heart rate increased for several hours after drinking alcohol. This alcohol-induced hypotension was marked in subjects showing facial flush identified by visual inspection after drinking, and was mild in those who did not show such flush. A transient pressor response to alcohol consumption was not observed in our study, and BP values the day after drinking were comparable to those on the control day.
Figure 1
Ambulatory blood pressure [BP] and heart rate during the alcohol intake day [•] and the control day [○]. *: P