Dietary risk factors of stroke and hypertension in Japan. I. Methodological assessment of urinalysis for dietary salt and protein intakes.

Relation of urinary urea to blood pressure: interaction with urinary sodium

“…20 [17][18][19][20] Previous studies show that urea in partial urine collections is a reliable index of 24-h urinary urea. [23][24][25][26][27][28] For urinary urea, special analyses were done on correlation with urinary total nitrogen and daily variability (see Appendix). Table 1 shows descriptive statistics for variables measured in overnight urine, age, anthropometry, physical activity, alcohol intake, smoking, and blood pressure status.…”

“…[30][31][32] For urea and other markers of protein intake, data in partial urine samples reflect data in 24-h urine. [23][24][25][26][27][28] Nevertheless, the use of overnight collection certainly implied some misclassification owing to lack of data on urea excretion after breakfast and/or lunch. The use of overnight instead of 24-h urine does not appear to have affected the data to a major degree since present findings are similar to data reported with use of 24-h urine.…”

Blood pressure, obesity and urine cation excretion in two populations of the Cook Islands.

“…The ratio of K/Cr in causal urine speciemen was also observed. Nevertheless, creatinine excretion is depended on age and lean body mass (Hallynck et al 1981), and, both Na/Cr and K/Cr tend to be higher in the afternoon than in the morning (Yamori et al 1982). Therefore, those ratios should be evaluated cautiously, especially when compared between age groups.…”

Evaluation of Nutritional Adaptation in the Field: An Application of Filter Paper Method for Urinalyis.

“…In their studies of a number of Japanese subjects, Yamori et al (1982) disclosed fairly good associations between the element concentrations in first-ofthe-morning urine and those in 24-hour urine, although the concentrations of Na, K, Cr, and UN in the former were slightly lower than those in the latter. …”

“…Physiologically, the ingested protein passes through a body nitrogen pool and is mostly excreted in urine, with small amounts of loss from feces and skin (Simmons, 1972). Main nitrogen compounds in the urine are in the form of urea nitrogen (UN), whose amount tends to fluctuate with the amount of protein intake (Yukawa, 1981;Yamori et al, 1982). In contrast, urinary creatinine (Cr) excretion reflects endogenous nitrogen loss, and its level is less affected by dietary intake than by the person's lean body mass (Heymsfield et al, 1983 Ohtsuka (1984) the six samples were selected for analysis, and each paper was put in a plastic tube to which distilled water was added for dillution.…”