There are no racial, age, sex, or weight differences in the effect of salt on blood pressure in salt-sensitive hypertensive patients.
BACKGROUND
This report is part of a larger, multicenter, placebo-controlled study designed to test the effects of low and high salt intake on the antihypertensive action of enalapril maleate or isradipine in salt-sensitive, hypertensive patients.


OBJECTIVE
To present our findings with respect to the effects of race, age, sex, and weight on the blood pressure response to low and high salt intake in salt-sensitive hypertensive patients before randomization into the larger study.


METHODS
After 3 week (weeks -9 to -6) of ad lib salt intake (100-200 mmol/d of sodium), 1916 patients whose sitting diastolic blood pressure was between 95 and 115 mm Hg entered a 3-week period (week -6 to -3) of low salt intake (50-80 mmol/d of sodium) and then a 3-week period (week -3 to 0) of high salt intake (200-250 mmol/d of sodium). Of the 1916 patients, 624 were identified as being sensitive to salt by demonstrating an increase in sitting diastolic blood pressure of equal to or more than 5 mm Hg from the low to high salt intake. Of these patients, 367 were white, 156 were black, 92 were Hispanic, 8 were Asian, and 1 was American Indian. Also, 315 were men and 309, women; 351 were 55 years or younger and 273 were older than 55 years; and 195 had a body mass index of 27 or less and 429 had a body mass index higher than 27.


RESULTS
The sitting blood pressure decreased with salt restriction and increased with salt load in all groups of patients (P < .001). There were no statistically significant differences in the blood pressure changes to salt changes by race, age, sex, and weight.


CONCLUSIONS
This large, multicenter study did not demonstrate any statistically significant effect of race, age, sex, and weight on blood pressure response to salt changes in salt-sensitive hypertensive patients.
Chrysant
S G
SG
Oklahoma Cardiovascular and Hypertension Center, Oklahoma City, USA.
Weir
M R
MR
Weder
A B
AB
McCarron
D A
DA
Canossa-Terris
M
M
Cohen
J D
JD
Mennella
R F
RF
Kirkegaard
L W
LW
Lewin
A J
AJ
Weinberger
M H
MH
D000375:Aging / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects*; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D006801:Humans; D006973:Hypertension / Q000209:etiology* / Q000503:physiopathology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D044469:Racial Groups; D012737:Sex Factors; D012982:Sodium, Dietary / Q000008:administration & dosage / Q000009:adverse effects*
D012982:Sodium, Dietary