Urinary sodium excretion and blood pressure in children: absence of a reproducible association.

A previous report by our group described a cross-sectional association between urinary sodium excretion and blood pressure (BP) in children. Attempts were made to reproduce these findings in two subsequent studies carried out with an identical protocol. Although descriptive results were similar and the correlations between measures of body size and blood pressure were reproduced, a clear-cut association between 7-day mean urinary sodium excretion and BP was observed only in the first of the three studies. These results could imply inadequate study methods, an inconsistent and weak relationship, or the absence of a relationship altogether. (Hypertension 5: 135-139, 1983)