THERE ARE NO RACIAL, AGE, SEX, OR WEIGHT DIFFERENCES IN THE EFFECT OFSALT ON BLOOD-PRESSURE IN SALT-SENSITIVE HYPERTENSIVE PATIENTS

Background: This report is part of a larger, multicenter, placebo-cont rolled study designed to test the effects of low and high salt intake on the antihypertensive action of enalapril maleate or isradipine in s alt-sensitive, hypertensive patients. Objective: To present our findin gs with respect to the effects of race, age, sex, and weight on the bl ood pressure response to low and high salt intake in salt-sensitive hy pertensive patients before randomization into the larger study. Patien ts and Methods: After 3 weeks (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 eq ual 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 As ian, 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 ha d 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 rest riction and increased with salt load in all groups of patients (P<.001 ). There were no statistically significant differences in the blood pr essure changes to salt changes by race, age, sex, and weight. Conclusi ons: This large, multicenter study did not demonstrate any statistical ly significant effect of race, age, sex, and weight on blood pressure response to salt changes in salt-sensitive hypertensive patients.