Associations between sodium, potassium, and blood pressure: results from the Hispanic Community Health Study/Study of Latinos, a prospective cohort study

Abstract

Background: Although the subject of numerous studies, the associations between dietary sodium, potassium, and the ratio of dietary sodium to potassium with blood pressure are not clear-cut. In addition, there is a paucity of research on these relationships in prospective cohort studies with representation from diverse Hispanic/Latino adults.

Objectives: To evaluate the associations between dietary intake of sodium, potassium, and the ratio of dietary sodium to potassium and blood pressure in a diverse sample of Hispanics living in the United States.

Methods: This analysis included 11,429 Hispanic/Latino participants of the prospective cohort Hispanic Community Health Study/Study of Latinos recruited between 2008 and 2011 in visit 1 who participated in a follow-up visit in 2014-2017. Dietary sodium and potassium intakes were averaged from 2 interviewer-administered 24-h diet recalls collected at visit 1. At both visits, blood pressure was measured 3 times in a seated position and averaged. We assessed the relationship between dietary sodium, potassium, and the sodium-to-potassium ratio with changes in systolic and diastolic blood pressure using survey-weighted multivariable-adjusted regression models.

Results: At visit 1, the mean age was 41 y, and the mean sodium intake was 3203 mg/d. Each 500 mg/d sodium increment in intake was associated with an increase in systolic blood pressure (β: 0.35 [mmHg]; 95% confidence interval: 0.06, 0.63) and diastolic blood pressure (β: 0.45 [mmHg]; 95% confidence interval: 0.08, 0.82). Dietary potassium and the molar ratio of dietary sodium to potassium were not associated with changes in systolic or diastolic blood pressure.

Conclusions: Among a large sample of diverse United States Hispanic/Latino adults, higher sodium intake was associated with small increases in systolic blood pressure over 6 y. This research underscores the importance of dietary sodium reduction in maintaining lower blood pressure.

Keywords: healthy eating; heart health; nutrition; nutritional epidemiology; salt.

FIGURE 1

Kernel density plots of intake of dietary sodium, potassium, and sodium-to-potassium ratio (24-h recall) at visit 1 among the Hispanic Community Health Study/Study of Latinos, 2008–2011.

FIGURE 2

Associations between self-reported sodium, potassium, sodium-to-potassium ratio, and 6-y change in systolic blood pressure (A), diastolic blood pressure (B), and incident hypertension (C) by Hispanic/Latino background, Hispanic Community Health Study/Study of Latinos 2008–2017.