Sodium sensitivity as a main determinant of blood pressure changes during early withdrawal in heavy alcoholics.

Abstract

Stimulated sympathetic nervous system, renin-angiotensin-aldosterone system, vasopressin, and cortisol are thought to affect blood pressure in early withdrawal of alcoholics. Hyperactivity of sodium-retaining systems with consequent volume expansion also could interact with sodium sensitivity as previously found in long-term withdrawing alcoholics. To investigate this hypothesis, blood pressure and sodium balance were measured during the first 8 days of withdrawal in 18 chronic alcoholics on a 150 mM Na diet. Results were related to the Salt Sensitivity Index of blood pressure as measured in the same alcoholics after 1 year of abstinence. Early withdrawal study: there was a positive sodium balance (+288.6 +/- 45.6 mM; p < 0.0001) and rise in mean arterial pressure (+11.8 +/- 2.9 mm Hg; p = 0.001) during early withdrawal on 150 mM Na diet. Salt Sensitivity Study after long-term detoxification: the shift from low (55 mM) to high sodium (260 mM) intake produced a larger (p = 0.04) increase in mean arterial pressure in alcoholics (+9.3 +/- 2.0 mm Hg) than in 30 teetotal controls (+5.1 +/- 1.1) (Salt Sensitivity Index, 0.047 +/- 0.008 vs. 0.023 +/- 0.0053; p < 0.05). Changes in mean blood pressure during withdrawal were highly related to sodium sensitivity index (r = 0.8; p < 0.001). Early withdrawing alcoholics exposed to a normal sodium intake experience positive Na balance and increase in blood pressure that is related to sodium sensitivity measured after long-term detoxification. This suggests that salt sensitivity plays a key role in blood pressure regulation in early withdrawing alcoholics.