Does decreased diastolic blood pressure associate with increased mortality in 80-year-old Japanese?
Hypertension is one of the greatest risk factors for cardiovascular disease, but its contribution to cardiovascular mortality weakens with aging. We have previously demonstrated that at the age of 80, higher systolic blood pressure (SBP) is not correlated with increased mortality in Japan. However, we did not examine in detail whether diastolic blood pressure (DBP) independently affects mortality. In the present study, 639 participants, who were 80 years old in 1997, were enrolled. The subjects were divided by their DBP [below 70 mmHg (group 1, n = 136), from 70 mmHg to 80 mmHg (group 2, n = 200), from 80 mmHg to 90 mmHg (group 3, n = 194), over 90 mmHg (group 4, n = 109)]. During the 4-year follow-up period, 90 individuals died. Cox multivariate regression analysis revealed that group 1 showed a significantly higher mortality rate than group 4 [relative risk (RR) 2.47, confidence interval (CI) 1.07-5.70, p = 0.03)]. The relative risks of deaths from cardiovascular diseases, pneumonia, and cancer tended to be higher in group 1 than in group 4, but the difference did not reach statistical significance. These results suggest that decreased DBP is associated with higher mortality in the Japanese elderly.
Kagiyama
Shuntaro
S
Division of General Internal Medicine, Department of Health Promotion, Science of Health Improvement, Kyushu Dental College, Kitakyushu, Japan. kagishu@hotmail.com
Takata
Yutaka
Y
Ansai
Toshihiro
T
Matsumura
Kiyoshi
K
Soh
Inho
I
Awano
Shuji
S
Sonoki
Kazuo
K
Yoshida
Akihiro
A
Torisu
Takehiro
T
Hamasaki
Tomoko
T
Nakamichi
Ikuo
I
Takehara
Tadamichi
T
Iida
Mitsuo
M
D000369:Aged, 80 and over; D000375:Aging; D044466:Asian People / Q000706:statistics & numerical data*; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000401:mortality / Q000503:physiopathology; D003430:Cross-Sectional Studies; D003971:Diastole; D005260:Female; D006801:Humans; D006973:Hypertension / Q000401:mortality* / Q000503:physiopathology*; D007564:Japan / Q000453:epidemiology; D008297:Male; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D015996:Survival Rate