Arterial effects of salt restriction in hypertensive patients. A 9-week, randomized, double-blind, crossover study.
OBJECTIVE
To investigate the hemodynamic effects of a moderately low-salt diet in a 9-week, randomized, double-blind, crossover study in 20 hypertensive, ambulatory patients.


METHODS
All subjects followed a 9-week, low-salt diet. During this period, they received capsules containing either lactose or salt in 4-week treatment periods, separated by a 1-week washout period. Hemodynamic and biological parameters were evaluated on the day of randomization and at the end of weeks 4 and 9. We defined a low-sodium diet (LSD) as a salt-restriction period with lactose capsules, and a normal-sodium diet (NSD) as a salt-restriction period with capsular salt supplementation.


RESULTS
Blood pressure was significantly lower during LSD compared with NSD. This fall in blood pressure was associated with a decrease in peripheral resistance in carotid and forearm circulation. Brachial artery diameter was larger during LSD whereas carotid artery diameter remained unchanged. The changes in brachial artery were: (1) not related to blood pressure changes; (2) positively related to age, and (3) negatively correlated with baseline intracellular sodium content.


CONCLUSIONS
These results suggest that moderate low-salt restriction is capable of decreasing blood pressure and peripheral resistance in carotid and forearm circulation. The increase in brachial, but not carotid, artery diameter following salt restriction suggests a difference in salt dependence among different arteries.
Benetos
A
A
Department of Internal Medicine, Broussais Hospital, Paris, France.
Xiao
Y Y
YY
Cuche
J L
JL
Hannaert
P
P
Safar
M
M
D000328:Adult; D001916:Brachial Artery / Q000502:physiology; D002339:Carotid Arteries / Q000502:physiology; D004039:Diet, Sodium-Restricted; D004311:Double-Blind Method; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D006973:Hypertension / Q000178:diet therapy* / Q000503:physiopathology; D008297:Male; D013997:Time Factors; D014655:Vascular Resistance / Q000502:physiology