Re: Revisiting the association of blood pressure with mortality in oldest old people in China: community based, longitudinal prospective study
The research article by Lv et al is a key addition to the growing literature on blood pressure outcomes in later life. This confirms the U shaped association of systolic blood pressure with all-cause mortality reported in an English cohort of 79,376 adults aged over 80 published in the Journal of the American Geriatric Society last year.(1) Lv and colleagues report that in cause specific analysis cardiovascular mortality was higher in those with systolic blood pressure >154 mmHg and systolic blood pressure of <107 mmHg was associated with a higher risk of non-cardiovascular mortality, with the lowest all-cause mortality between 120 and 140 mmHg. However, these findings ignore the dynamic nature of blood pressure with advancing age and proximity to death, and the potential for reverse causation. Blood pressure peaks 14 to 18 years prior to death and declines steadily with diminishing time to death (2,3). These dynamic changes should be accounted for in studies investigating associations between blood pressure and mortality. We agree that further work is required to consider the relevance of blood pressure guidelines, and blood pressure within specific subgroups, to the oldest adults.
1. Delgado J, Masoli JAH, Bowman K, Strain WD, Kuchel GA, Walters K, et al. Outcomes of Treated Hypertension at Age 80 and Older: Cohort Analysis of 79,376 Individuals. J Am Geriatr Soc. 2017 May;65(5):995-1003
2. Delgado J, Bowman K, Ble A, Masoli J, Han Y, Henley W, et al. Blood Pressure Trajectories in the 20 Years Before Death. JAMA Intern Med. 2018 Jan 1;178(1):93-99
3. Ravindrarajah R, Hazra NC, Hamada S, Charlton J, Jackson SH, Dregan A, et al. Systolic blood pressure trajectory, frailty and all-cause mortality over 80 years of age. Cohort study using electronic health records. Circulation. 2017 Jun 13;135(24):2357-2368
Competing interests: No competing interests