Blood pressure and 40 month mortality in elderly Chinese subjects aged 70 years and over.

The association between blood pressure and 4 year mortality was examined in a cohort of 970 Chinese subjects aged 70 years and above. After adjusting for age, sex, body mass index, smoking habit, place of residence, and the presence of heart or chronic lung diseases, a U-shaped association between blood pressure and mortality was observed, the risks of mortality among subjects in the extreme quartiles being twice as high as those in the middle quartiles. Subjects with the lowest systolic blood pressure quartile also had a higher risk of developing functional limitations.