Alcohol raises blood pressure in hypertensive patients

The acute effect of drinking beer on blood pressure was studied in 18 hypertensive patients who were either regular, moderate (MI) or low intake (LI) drinkers. Patients in the MI group showed a significant rise in systolic blood pressure (SBP; average 12 mmHg) and pulse rate with alcohol, but no change after alcohol-free drink. No such changes with alcohol were seen in LI patients. There was a small transient rise in diastolic pressure (DBP) in response to alcohol in both the MI and LI patients. Resting plasma catecholamine levels were similar in both groups but only the MI group showed a significant rise in plasma noradrenaline (P less than 0.05) with alcohol, paralleling the rise in SBP and pulse rate. Plasma renin activity (PRA) and cortisol were unaffected by alcohol. In both groups significant falls in plasma calcium levels occurred with alcohol. The greater haemodynamic changes with alcohol in the MI group were associated with increased sympathetic activity. Chronic moderate alcohol intake, however, does not alter resting plasma catecholamine levels, at least, after hypertension is established.