The age-related blood pressure trajectories from young-old adults to centenarians: A cohort study

Highlights

• This study depicts the age-related BP trajectories among people aged 60-105 years.

• Higher BP levels are related to a short survival in older adults until ∼80 years of age.

• SBP and PP exhibit steeper declines over 2 years prior to death in people aged ≥80 years.

• The age-related BP trajectories vary by birth cohorts and antihypertensive therapy.

• After ∼80 years, a history of heart disease relates to steeper declines in SBP and PP.

Abstract

Background

Blood pressure (BP) trajectories among older adults, especially among the oldest-old, are still poorly characterized.

Objective

To investigate the longitudinal trajectories of four BP components with age and their potential influential factors.

Methods

This population-based prospective cohort study included 3315 participants (age 60–105 years, 64.6% women) who were regularly examined from 2001 to 2004 through 2013–2016. The longitudinal trajectories of systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP), and mean arterial pressure (MAP) with age were estimated using linear mixed-effects models.

Results

Overall, SBP and PP increased with age until ∼80 years and then declined, whereas DBP and MAP decreased constantly after 60 years of age. The age-related BP trajectories varied by survival time, birth cohort, use of antihypertensive drugs, and heart disease. Specifically, people who survived <2 years after the last visit showed higher levels of BP components before ∼80 years, followed by steeper declines in SBP and PP. At the same age, people who were born earlier showed higher BP than those who were born later. People who used antihypertensive drugs had higher BP than those who did not until ∼80–90 years old, thereafter BP showed no significant difference. After ∼80 years old, people with heart disease showed steeper declines in SBP and PP than those without.

Conclusions

The late-life longitudinal BP trajectories with age vary with demographics, clinical conditions, and contextual factors. These findings may help better understand the age-dependent relationship of BP with health outcomes as well as help achieve optimal BP control in older people.

Perspectives

Competency in medical knowledge: Understanding the age-related blood pressure trajectories and potential influential factors may help improve blood pressure management in older people.

Translational outlook 1: Blood pressure trajectories with age in older adults vary by birth cohort, survival time, antihypertensive therapy, and heart disease. The age-related blood pressure trajectories by birth cohorts are featured with lower blood pressure levels at the same age in more recent birth cohorts, which may partially reflect the improvement of blood pressure control over time.

Translational outlook 2: The age-related blood pressure trajectories in the oldest old (e.g., age ≥ 85 years) are characterized by steeper and faster blood pressure declines associated with heart disease and short survival (e.g., <2 years). This may have implications for the optimal management of blood pressure as well as for the interpretation of the relationships between blood pressure and health outcomes (e.g., death) among the oldest old.

Introduction

High blood pressure (BP) is a major risk factor for cardiovascular disease, cognitive decline, and poor survival, but its deleterious effect may decrease with advancing age [[1], [2], [3], [4]], and among the oldest old low BP may anticipate an increased risk of all-cause mortality [[5], [6], [7]]. Thus, capturing the longitudinal patterns of BP trajectories with age in older adults, and detecting their influential factors may help better understand the potential pathways linking BP levels with adverse health outcomes.

Beyond systolic BP (SBP) and diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP), the two hemodynamic parameters derived from SBP and DBP, can be extremely informative in predicting the risk of cardiovascular events and mortality. MAP measures vascular resistance and cardiac output, and PP reflects artery stiffness and wave reflections. It has been suggested that models combining various BP components are superior to those of single components in predicting the risk of cardiovascular disease [8]. However, population-based cohort studies investigating the longitudinal BP trajectories in older people have either missed the oldest old people (e.g., ≥85 years) [2,[9], [10], [11]], or only focused on SBP and DBP [12,13]. Studying the age-related BP trajectories that involve all 4 BP components among the oldest old is important because the relationship between various BP components and health outcomes is much more complex in the oldest old than in middle-aged and young-older adults.

Furthermore, data from the USA (age 18–74 years), the UK (age 35–80 years), and Norway (age 20–89 years) showed that distribution of both SBP and DBP shifted downward from earlier to more recent birth cohorts [[14], [15], [16]]. This suggests the potential birth cohort effects on BP trajectories with age in young and older adults. Whether a birth cohort effect could prejudice patterns of age-related BP trajectories in a population that includes also the oldest old remains to be clarified.

In addition, a population-based study of older adults in northern Sweden suggested that improvement in antihypertensive therapy might partly explain a downward trend in SBP and DBP over time [17]. Moreover, increased variability in SBP from midlife to old age is associated with a higher risk of heart disease and mortality [18]. Conversely, heart disease may also cause fluctuations in BP with age in late life. Finally, age might modify the relationship between BP and mortality in older adults [6,19], suggesting that the age-related trajectories of late-life BP may vary with the length of survival time. However, whether these factors can affect age-related BP changes later in life remains uncertain.

Therefore, in this population-based prospective cohort study of people aged 60–105 years in central Stockholm, Sweden, we aim to investigate the age-related longitudinal trajectories of SBP, DBP, PP, and MAP by sex, birth cohort, and survival status, and further to explore whether and to what extent heart disease and use of antihypertensive drugs can modify the age-related trajectories of late-life BP.