Abstract P335: Salt Sensitivity and Incidence of Hypertension: The GenSalt Study

Abstract

It is well known that blood pressure (BP) responses to dietary sodium and potassium intakes vary among individuals (salt- and potassium-sensitivity). However, it is unknown whether salt- and/or potassium-sensitivity predict the risk of hypertension. We conducted a dietary sodium and potassium intervention study among 1,906 Han Chinese in 2003-05 and followed the study participants in 2008-09 and 2011-12. The dietary intervention included a 7-day low sodium-feeding (51.3 mmol/day), a 7-day high sodium-feeding (307.8 mmol/day), and a 7-day high sodium-feeding with an oral potassium supplementation (60 mmol/day). Three BP measurements were obtained on each of the last 3 days of each intervention period at the baseline and each of the 3 days of follow-up examinations. Systolic BP responses (mean ± SD) to dietary intervention were -5.5±7.0 for low-sodium, 4.9±6.0 for high-sodium, and -3.5±5.5 for potassium-supplementation. Over an average of 7.4 years of follow-up, we identified 455 incidence hypertension cases (systolic BP≥140 mmHg and/or diastolic BP ≥90 mmHg and/or use of antihypertensive medication). The age-adjusted cumulative incidences of hypertension by the quartiles of systolic BP responses to dietary intervention were showed in the following table. These associations remained after adjustment for multiple covariates. These data indicate that BP responses to dietary sodium and potassium intervention are related to the subsequent risk of hypertension. Furthermore, our study suggests that individuals who are more sensitive to dietary sodium and potassium intake are at an increased risk for hypertension and should be target for dietary intervention.