[Changes in 24-hour urinary excretion of sodium and potassium in a community-based heath education program on salt reduction].
OBJECTIVE
To examine changes in urinary excretion of sodium, potassium and sodium/potassium ratio in a community-based health education program on salt reduction.


METHODS
The surveyed community was Kyowa town (census population in 1985 = 16,792) where we have conducted a community-based blood pressure control program since 1981 and health education on reduction of salt intake since 1983 for primary prevention of hypertension. A 24-hour urine collection was conducted for systematically selected samples of the participants aged 40-69 in cardiovascular risk surveys in 1982-86 (early period) and in 1990-94 (later period) to estimate changes in urine excretion of sodium, potassium, and sodium/potassium ratio.


RESULTS
A 24-hour urine collection was available for 565 persons (410 men and 155 women) in 1982-86 and 1,461 persons (571 men and 890 women) in 1990-94. A decline in mean sodium excretion was larger in ages 40-49 than in other age groups, and for ages 40-69 combined, the decline was 0.9-1.1 g per day for men and women. Mean sodium excretion declined to 10 g or less per day for men and women aged 60-69. Mean potassium excretion did not change except for men aged 60-69 with an increase in potassium. Sodium/potassium ratio tended to decline for women aged 40-49, and declined significantly for other sex-age groups. A larger reduction in sodium excretion was seen among persons with a history of hypertension compared to those without it.


CONCLUSIONS
A significant reduction in urinary excretion of sodium and sodium/potassium ratio was observed in a community-based health education program. Men and women aged 60-69 reached a recommended level of 10 g or less in sodium intake.
Iso
H
H
Institute of Community Medicine, University of Tsukuba.
Shimamoto
T
T
Yokota
K
K
Ohki
M
M
Sankai
T
T
Kudo
M
M
Harada
M
M
Wakabayashi
Y
Y
Inagawa
M
M
Kitamura
A
A
Sato
S
S
Imano
H
H
Iida
M
M
Komachi
Y
Y
D000328:Adult; D000368:Aged; D002940:Circadian Rhythm; D004039:Diet, Sodium-Restricted; D005260:Female; D006266:Health Education; D006801:Humans; D006973:Hypertension / Q000652:urine; D008297:Male; D008875:Middle Aged; D009318:Natriuresis / Q000502:physiology*; D011188:Potassium / Q000652:urine*; D012965:Sodium Chloride / Q000008:administration & dosage
D012965:Sodium Chloride; D011188:Potassium