Association between High Blood Pressure and Intakes of Sodium and Potassium among Korean Adults: Korean National Health and Nutrition Examination Survey, 2007-2012

J Acad Nutr Diet. 2015 Dec;115(12):1950-7. doi: 10.1016/j.jand.2015.04.021. Epub 2015 Jun 27.

Abstract

Background: The association between dietary sodium and potassium, the ratio of sodium to potassium, and blood pressure remains unclear.

Objective: We evaluated the associations between blood pressure and dietary sodium and potassium intake in terms of the amount and ratio in Korean adults.

Design: This cross-sectional study was based on data from the fourth and fifth Korean National Health and Nutrition Examination Survey, 2007-2012.

Participants/setting: A total of 24,096 adults (aged ≥19 years) without history of antihypertensive medication use were selected. The 24-hour recall method was used for dietary assessment. We categorized the subjects into four groups using median intakes of sodium and potassium, and defined the low sodium/high potassium intake group as the reference group.

Main outcome measures: High blood pressure (HBP) was defined as mean systolic or diastolic blood pressures of ≥140 or ≥90 mm Hg, respectively.

Statistical analyses performed: Multivariate logistic regression was performed to estimate the odds ratio and 95% CI to investigate the association between the four groups of sodium and potassium intakes and HBP.

Results: Sodium intake was positively associated with diastolic blood pressure, with an increase of 0.21 mm Hg per 1 mg/kcal increase in sodium (P<0.001). In contrast, potassium intake was negatively associated with systolic blood pressure, with a decrease of 1.01 mm Hg per 1 mg/kcal increase in potassium (P<0.001). After adjusting for confounders, the high sodium/low potassium (odds ratio 1.21, 95% CI 1.02 to 1.44) and low sodium/low potassium intake groups (odds ratio 1.19, 95% CI 1.01 to 1.40) were at higher risk of HBP than the reference group. The risk of HBP in the high sodium/high potassium group did not differ from that in the reference group.

Conclusions: Low potassium intake was associated with an increased risk of hypertension. These results suggest that increasing potassium intake might be beneficial for hypertension control among populations with low-potassium diets.

Keywords: Blood pressure; Hypertension; Potassium; Sodium.

MeSH terms

  • Adult
  • Blood Pressure
  • Cross-Sectional Studies
  • Diastole
  • Diet Records
  • Female
  • Humans
  • Hypertension / etiology*
  • Hypertension / prevention & control
  • Logistic Models
  • Male
  • Middle Aged
  • Nutrition Surveys*
  • Odds Ratio
  • Potassium, Dietary / administration & dosage*
  • Republic of Korea
  • Risk Factors
  • Sodium, Dietary / administration & dosage*
  • Systole

Substances

  • Potassium, Dietary
  • Sodium, Dietary