Changing prediction of mortality by systolic blood pressure with increasing age: the Rotterdam study

Abstract

There are indications that in persons of older age, systolic blood pressure (SBP) is no longer associated with mortality. This raises the question whether the predictive value of SBP changes from younger to older age groups. Analysis in the Rotterdam Study, a population-based prospective cohort study among 4,612 participants aged ≥55 years without previous cardiovascular disease and with a median follow-up of 14.9 (interquartile range, 11.1-15.8) years. Within four age groups (55-64, 65-74, 75-84, ≥85 years), the predictive value of baseline SBP for mortality was studied. From age 55 to ≥85 years, risk of all-cause mortality associated with SBP ≥160 mmHg decreased from HR 1.7 (95%CI 1.2-2.2) to HR 0.7 (95%CI 0.4-1.1), p for trend <0.001. For participants with SBP 140-159 mmHg, the risk decreased from HR 1.2 (95%CI 0.9-1.5) to HR 0.7 (95%CI 0.5-1.1), p for trend <0.001. Analyses in the 5-year age groups showed an increased risk with higher SBPs up to age 75 years. After 75 years, a trend towards SBP no longer being associated with an increased mortality risk was seen in our study. These findings need to be considered with recently reported beneficial effects of antihypertensive treatment in this age group.

Fig. 1

Absolute risk of mortality by age group, depending on the level of systolic blood pressure (SBP). Left axis number of deaths per 1,000 person-years. Bottom axis age group (years)