2-WAY FACTORIAL STUDY OF ALCOHOL AND SALT RESTRICTION IN TREATED HYPERTENSIVE MEN

The aim of this study was to determine whether moderate restriction of dietary salt intake leads to an additional fall in blood pressure in treated hypertensive men who are asked to simultaneously reduce their usual alcohol intake. Sixty-three subjects entered an initial 2-week familiarization period during which they continued their usual alcohol intake and commenced a 'low sodium' diet (less than 60 mmol/day) supplemented with 100 mmol sodium chloride per day as enteric-coated tablets. Subjects were then randomly assigned to either drink a low alcohol beer alone for a 4-week period (reducing their self-reported alcohol consumption from 537 to 57 ml/week) or to continue their usual alcohol intake (543 versus 557 ml/week). Within the low and normal alcohol intake groups, subjects were assigned to either a low or normal sodium intake. The low sodium groups continued the sodiu-restricted diet but were switched to placebo sodium chloride tablets for the 4 weeks. This resulted in a fall in the 24-hour urinary sodium excretion from 144 to 69 mmol/day. The normal sodium groups continued the low sodium deit but kept taking 100 mmol/day of the sodium chloride tablets, and their urinary sodium excretion remained unchanged (125 versus 142 mmol/day). Regular antihypertensive therapy was continued throughout. Fifty-nine subjects completed the trial. In those who reduced their alcohol intake there was a fall in boht systolic blood pressure (-5.4 mm Hg supine, p< 0.01) and diastolic blood pressure (-3.2 mm Hg supine, p < 0.01). There was no effect of salt restriction on blood pressure and no evidence of an additive effect of alcohol and salt restriction. The results indicate that, in a selected sample of treated hypertensive drinkers, a short-term and moderate reduction in salt intake in addition to a substantial decrease in alcohol intake does not lead to a greater fall in blood pressure than that seen with alcohol restriction alone.