Relationship between blood pressure level and mortality rate: an 18-year study conducted in two rural communities in Japan.
BACKGROUND
There have been very few studies on life prognosis of cardiovascular disease according to blood pressure stratification in the Japanese. Therefore, in Japan, although treatment of hypertension is possible, albeit at times difficult, due to the availability of various antihypertensive medications, the appropriate time at which treatment should be started remains a problem.


OBJECTIVE
To investigate the long-term prognosis of cardiovascular disease in the Japanese general population according to blood pressure stratification in the Japanese.


METHODS
A community-based prospective cohort study of 1996 men and women between the ages of 40 and 64 years at the baseline examination was conducted over an 18-year period. Information on death was obtained from local public health nurses and death certificates. The causes of death were clarified by questionnaires sent to doctors in the hospital in which the deceased was hospitalized, and the causes of death were analysed in each blood pressure category at baseline examination.


RESULTS
Mortality from cardiovascular disease increased with increases in the level of blood pressure and was significantly higher in > or = 140 mmHg group in systolic blood pressure and > or = 90 mmHg group in diastolic blood pressure, adjusted for age, sex and other cardiovascular risk factors in the Japanese general population. However, mortality risk from cardiovascular disease did not have a J-shaped relationship with systolic and diastolic blood pressure.


CONCLUSIONS
We conclude that the optimum time for starting treatment in Japanese people is when blood pressure is 140/90 mmHg or less.
Takagi
S
S
Second Department of Internal Medicine, Sapporo Medical University School of Medicine, Japan. takagis@sapmed.ac.jp
Saitoh
S
S
Nakano
M
M
Hayashi
Y
Y
Obara
F
F
Onishi
H
H
Shimamoto
K
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000401:mortality / Q000503:physiopathology / Q000517:prevention & control; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000401:mortality* / Q000503:physiopathology; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D012424:Rural Population
D000959:Antihypertensive Agents