Relationship of blood pressure to sodium and potassium excretion in Japanese women.

Abstract

The cross-sectional association of blood pressure with urinary sodium and potassium excretion was investigated with a stepwise regression analysis. Spot urine of 7441 females between 40 and 69 years was collected from 169 municipalities (88 urban and 81 rural) covering all prefectures in Japan. The filter paper sampling technique for urine was used to collect samples of subjects from March to December in 1985. Spot urine samples were analyzed for sodium, potassium and creatinine. In addition, 24-hr sodium and potassium excretions were estimated by predictive equations. Blood pressure, sodium excretion and sodium/potassium ratios were higher in rural areas than in urban areas. Consistent positive correlations between urinary sodium and blood pressure, and negative correlations between urinary potassium and blood pressure were observed in the whole country of Japan, in both urban and rural areas, and also in separate observations of twelve regions in Japan with some exceptions. When compared in standardized partial regression coefficients, relative effects of potassium on systolic blood pressure were higher than those of sodium in the whole of Japan, in urban and rural areas, and in five among the twelve regions. The present Japanese study confirmed a positive within-population relationship between sodium excretion and blood pressure and a negative relationship between potassium excretion and blood pressure.

Relationship of Urinary Sodium and Potassium and of Urinary Sodium/Creatinine, Potassium/Creatinine and Sodium/Potassium Ratios to Stomach Cancer and Cerebrovascular Disease Mortalities in Japanese Women.

“…In the present study, the data on Na, K, Na/Cr, K/Cr and Na/K in urine are cited from previous studies (Takemori et al 1988(Takemori et al , 1989. Subjects and the method of collecting urine sample and the relevant particulars including the season of urine collection and the reasons of limiting the subjects to female were discussed in the previous studies.…”

“…The mean sodium intake and blood pressure levels have been found to be correlated in the general population (Gleibermann 1973;Simpson 1985). Some within-population studies on Oriental populations (Kesteloot et al 1980(Kesteloot et al , 1987Takemori et al 1989) ) have indicated that a high intake of salt, pickled vegetables, dried/salted fish, and a low intake of raw vegetables, fresh fruits and citrus fruits are associated with the development of SC. In the study on the taste for salt (Tuyns 1988), among people who systematically added salt to their food, high relative risks for SC, colon cancer and rectal cancer were observed.…”

“…The data on the Na, K, and Na/creatinine (Cr), K/Cr, and Na/K ratios in urine are cited from previous publications (Takemori et al 1988(Takemori et al , 1989. Briefly, a prefectural seat, and a city and two towns or villages were randomly selected from each prefecture in Japan.…”

“…The filter paper sampling technique for urine (Takemori 1980) was used to collect urine samples from March to December in 1985. The details of collection and analyses have been described previously (Takemori 1981;Takemori et al 1989). The Na/Cr (mmol/g), K/Cr (mmol/g), and Na/K(mmol/mmol) ratios were calculated on the basis of the concentration of Na, K and Cr in the spot urine.…”

Relationship between Dietary Cations and Blood Pressure

“…In general, Oriental populations have lower levels of in take of about 40 mmol/day in men com pared to around 70 mmol/day in Western populations. Referring to the same popula tion in which the independent relationships between sodium and blood pressure have been measured, and including the Intersalt study, the following statements can be made: (1) an independent significant relationship between potassium and blood pressure oc curred less frequently compared to sodium; (2) whenever significant the slope of the re gression relating potassium to blood pres sure was 2-4 times more important than that for sodium [2,3,9]. As potassium lowers blood pressure and sodium increases it, the Na/K ratio often shows the best correlations with blood pressure.…”