Gender difference in blood pressure responses to dietary sodium intervention in the GenSalt study.
OBJECTIVE
To examine factors related to blood pressure (BP) responses to dietary sodium and potassium interventions.


METHODS
We conducted a dietary feeding study that included a 7-day low-salt intervention (51.3 mmol sodium/day), a 7-day high-salt intervention (307.8 mmol sodium/day), and a 7-day high-salt and potassium-supplementation (60 mmol potassium/day) intervention among 1906 study participants in rural China. The BP was measured nine times during the 3-day baseline observation and during the last 3 days of each intervention phase using a random-zero sphygmomanometer.


RESULTS
The BP responses to low-sodium intervention were significantly greater in women than in men: -8.1 [95% confidence interval (-8.6 to -7.6)] versus -7.0 (-7.5 to -6.6) mmHg for systolic and -4.5 (-4.9 to -4.1) versus -3.4 (-3.8 to -3.0) mmHg for diastolic. Likewise, BP responses to high-sodium interventions were significantly greater in women than in men: 6.4 (5.9-6.8) versus 5.2 (4.8-5.7) mmHg for systolic and 3.1 (2.7-3.5) versus 1.7 (1.4-2.1) mmHg for diastolic (all P < 0.001). In addition, systolic BP responses to sodium interventions increased with age, and both systolic and diastolic BP responses to sodium interventions increased with baseline BP levels. BP responses to potassium supplementation also increased with baseline BP levels.


CONCLUSIONS
These results suggest that female gender, older age, and hypertension increase the sensitivity to dietary sodium intervention. Furthermore, low dietary sodium intake may be more effective in reducing BP among these subgroups.
He
Jiang
J
Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana 70112, USA. jhe@tulane.edu
Gu
Dongfeng
D
Chen
Jing
J
Jaquish
Cashell E
CE
Rao
Dabeeru C
DC
Hixson
James E
JE
Chen
Ji-chun
JC
Duan
Xiufang
X
Huang
Jian-feng
JF
Chen
Chung-Shiuan
CS
Kelly
Tanika N
TN
Bazzano
Lydia A
LA
Whelton
Paul K
PK
D000328:Adult; D001794:Blood Pressure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000652:urine; D017419:Potassium, Dietary / Q000008:administration & dosage*; D012727:Sex Characteristics; D012964:Sodium / Q000652:urine; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage*
D017419:Potassium, Dietary; D017673:Sodium Chloride, Dietary; D012964:Sodium; D011188:Potassium