TY - JOUR TI - Blood pressure, dietary sodium intake, and kidney function in U.S. adults DO - https://doi.org/doi:10.7282/t3-nyhe-zc75 PY - 2019 AB - High blood pressure is an independent predictor of cardiovascular disease and is associated with a higher risk of end-stage kidney disease. Whereas healthy kidneys can handle a high dietary sodium load before reaching a blood pressure (BP) threshold, a salt-sensitive increase in BP occurs when kidney function is reduced. However, the presence of confounders may influence the ability to demonstrate the BP response. The purpose of this research was to compare dietary sodium exposure and systolic BP (SBP) and diastolic BP (DBP) of U.S. adults according to kidney function level while accounting for potential confounders using NHANES data from 2003-2014. A causal framework approach was used to choose potential confounders of the dietary sodium-to-BP relationship. The mean (standard error [SE]) age was 47.3 (0.2) years, 49.4% (n=14,094) were male, 69.9 (n=13,199) were non-Hispanic White. Body mass index was ≥ 25 kg/m2 in 68.4% (n=19,442) and 13.6% (n=5,001) had evidence of diabetes. Hypertension (BP >140/90 mmHg or taking antihypertensive agents) was evident in 35.3% (n=11,373) yet only 26.7% (n=8,786) reported taking antihypertensive agents. The mean (SE) estimated glomerular filtration rate (eGFR) was 85.1 (0.4) ml/min/1.73m2. The mean (SE) dietary sodium was 3,526 (16) mg/day or 8.8 (0.1) grams of salt/day. The mean (SE) SBP was 122.4 (0.2) mmHg and DBP was 70.9 (0.2) mmHg. BP was <120/80mmHg in 46.6% (n=12,180). After conditioning on demographic and clinical variables, the dietary sodium exposure-to-BP relationship was negligible: -0.04mmHg decrease in SBP for every 200mg increase in dietary sodium (p=.018) and 0.02mmHg increase in DBP for every 200mg increase in dietary sodium, p=.200). Stated differently, a 1mmHg decrease in SBP for every 5g increase in dietary sodium or 12.7g increase in NaCl and a 1mmHg increase in DBP for every 10g increase in dietary sodium or 25.4 g NaCl. This study demonstrated that a clinically relevant relationship between dietary sodium intake on the day prior to blood pressure measurements and systolic and diastolic blood pressure was not apparent. Several demographic and clinical characteristics (kidney function, gender, race, income but not education, BMI, evidence of diabetes) influence the dietary sodium-to-blood pressure relationship. KW - Health Sciences KW - Blood pressure KW - Sodium KW - Renal circulation LA - eng ER -