title: Does decreased diastolic blood pressure associate with increased mortality in 80-year-old Japanese?
abstract: 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.
authors.affiliation: Division of General Internal Medicine, Department of Health Promotion, Science of Health Improvement, Kyushu Dental College, Kitakyushu, Japan. kagishu@hotmail.com
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Kagiyama
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Takata
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Ansai
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Matsumura
authors.forename: Inho
authors.initials: I
authors.lastname: Soh
authors.forename: Shuji
authors.initials: S
authors.lastname: Awano
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sonoki
authors.forename: Akihiro
authors.initials: A
authors.lastname: Yoshida
authors.forename: Takehiro
authors.initials: T
authors.lastname: Torisu
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hamasaki
authors.forename: Ikuo
authors.initials: I
authors.lastname: Nakamichi
authors.forename: Tadamichi
authors.initials: T
authors.lastname: Takehara
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Iida
mesh_terms: 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