These cross-sectional results show a strong dose-response association between urinary sodium excretion and blood pressure, and an inverse association between urinary potassium excretion and blood pressure, in a nationally representative sample of US adults.

This report explains the creation of the 2017–March 2020 Pre-Pandemic Data Files, provides recommendations for and limitations of the files’ use, and presents prevalence estimates for select health outcomes based on the files.

Estimates of UIC, I/Cr, and estimated 24-hour UIE (I/Cr × predicted 24-hour Cr) from spot urine samples should not be used interchangeably. Estimated 24-hour UIE, where predicted 24-hour Cr varies by age, sex, ethnicity, and anthropometric measures and was calculated with prediction equations using data from the sample, was more comparable to observed 24-hour UIE than when predicted 24-hour Cr was from published estimates from a different population. However, currently no cutoffs exist to interpret population estimated 24-hour UIE values.

This report describes the creation of the NHANES 2017–March 2020 prepandemic data files.