Cumulative pulse pressure load tied to all-cause death in older adults

Long-term exposure to elevated cumulative pulse pressure (cPP) potentially increases the risk of all-cause deaths, while prolonged exposure to elevated cumulative systolic blood pressure (cSBP) contributes to a higher risk of cardiovascular death, suggests a study.

Of note, neither cSBP nor cumulative diastolic BP (cDBP) load are associated with dementia.

"Preventive efforts to improve vascular health and reduce aortic stiffness throughout the life-course may attenuate long-term PP to reduce mortality in late life,” the researchers said.

This study was conducted in Sydney, Australia, involving 1,037 community-dwelling adults aged 70–90 years. The research team obtained baseline data in 2005–2007 and followed the participants until 2021.

To calculate the cSBP load, the area under the curve (AUC) for SBP ≥140 mm Hg was divided by the AUC for all SBP values. The cumulative diastolic BP (cDBP) and cPP load were calculated with 90 and 60 mm Hg as thresholds, respectively. Associations were explored using Cox and mixed linear models.

Cognitive decline

A total of 527 participants had both seated and standing BP data (median age 77 years, 47.7 percent men), of whom 152 (28.8 percent) developed dementia over a mean follow-up of 10.5 years. [J Hypertens 2024;42:1922-1931]

In multivariate analysis, higher cPP load significantly correlated with an increased risk of all-cause mortality, while cSBP load contributed to an increase in the risk of cardiovascular deaths (p<0.05 for trend). However, after adjusting for age, the association of cPP load with dementia and cognitive decline lost statistical significance.

In addition, the differences between sitting and standing BP load did not show any significant association with the outcomes.

“Our study highlights the importance of long-term exposure to high PP in people aged 70 plus,” the researchers said. “Higher cPP, particularly cPP load, [was] associated with a higher risk of dementia and cognitive decline, but upon adjustment for age our results lost significance.”

In an earlier study of 7,207 women aged 65–79 years, elevated PP was found to contribute to an increased risk of cognitive impairment. [Lancet Healthy Longev 2022;3:e42-e53]

“Further studies are needed to gain a better understanding of the relationships between cumulative PP exposure, age, and dementia or cognition,” according to the researchers.

BP control in midlife

“The intricate relationship between BP and dementia, as well as cognitive function, has been studied extensively in recent years, often yielding conflicting results,” the researchers said. “In our study, no associations were found between mean BP and dementia and cognition.” [Nat Rev Cardiol 2010;7:686-698; Lancet Healthy Longev 2022;3:e42-e53; Alzheimers Res Ther 2017;9:1-12]

Notably, the study population had a mean age of 77 years. Several studies suggested that increased BP during midlife, rather than late life, was associated with late-life cognitive impairment. Therefore, effectively BP management in midlife could prevent cognitive impairment or dementia in later life. [Lancet 2020;396:413-446]

“This modifiable lifestyle intervention has been incorporated into certain trials, such as the SPRINT trial,” the researchers said. “In contrast, some evidence suggest that low BP in midlife predicts dementia in later life, potentially due to reduced blood flow to the brain which may contribute to the development of dementia.” [Alzheimers Res Ther 2017;9:1-12; JAMA 2019;321:553-561]