Blood Pressure Variability May Be Linked To Dementia Risk Later In Life

A long-term cohort study of 820 older adults found that greater year-to-year systolic blood pressure variability was associated with a 35% higher dementia risk at age 90, but not at ages 60, 70 or 80. The observational findings suggest late-life blood pressure fluctuations may signal increased risk; they do not prove that variability causes dementia or establish a specific treatment.  

Blood Pressure Variability May Be Linked To Dementia Risk Later In Life
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Dr. Chrysoula I. Liakou MD, PhD Google Scholar LinkedIn

Internal Medicine Specialist
Cancer Immunology Researcher

What the Study Reveals About Blood Pressure Variability and Dementia Risk

  • Research suggests that individuals who have fluctuating blood pressure in their middle-age years may be more likely to develop dementia when they reach their 90s.

  • It is still being determined what the best approach is to managing fluctuations in blood pressure levels.

  • People in their sixties, seventies, and eighties should still be aware of the potential health risks of high blood pressure.

A research paper published in JAMA Neurology suggests that elderly individuals with higher rates of fluctuation in their blood pressure may be more likely to develop dementia.


Kaiser Permanente Washington collaborated with researchers from Radboud University in the Netherlands to investigate if an individual's blood pressure changing frequently during middle age could be associated with a heightened risk of developing dementia in later life.


The study focused on 820 elderly persons aged between 65 and 90. At the beginning of the experiment and every two years afterwards, the individuals underwent a medical evaluation - including a mental examination.


The trial included elderly individuals living in the community who did not have cognitive impairments when the study began. All participants were aged 65 or above.


The information used in this study was collected from participants of the Adult Changes in Thought (ACT) study, a long-term survey of individuals.


The study showed that people in their 90s were at a higher risk of developing dementia if their blood pressure variability rate was high. Those aged 60, 70 or 80 were not affected by this rate.


They noted that high blood pressure remains a health risk factor for individuals aged 60 to 90.


The study revealed that fluctuations in blood pressure, as assessed through annual check-ups over three decades, were linked to the risk of dementia in individuals aged 90 or older. Notably, the connection between high systolic blood pressure and dementia varied between younger and older individuals, although it did not reach statistical significance.



Everyone Has Blood Pressure Fluctuations.


Blood pressure naturally fluctuates throughout the day for most individuals, a common occurrence outlined by Harvard Health. These fluctuations can happen rapidly, even within minutes.


A 2020 report published in the Hypertension Journal identified potential factors contributing to blood pressure variability. These include factors such as ageing, gender (being female), body weight, smoking habits, alcohol consumption, psychological stress, how blood vessels respond to changes like cold exposure, and the presence of certain conditions affecting organs like the heart, kidneys, and blood vessels, including left ventricular hypertrophy, chronic kidney disease, peripheral vascular disease, and subclinical atherosclerotic disease.



What Is Blood Pressure Variability


A report published in 2018 in the Journal of Clinical Hypertension noted that blood pressure variability can be a short-term occurrence. These variations can be categorised into irregular patterns without a consistent trend and those with well-defined patterns over time. It's important to note that aside from dementia, these periodic blood pressure readings can also serve as indicators of cardiovascular risk.


In a recent study, hypertension was found to be associated with a higher risk of dementia in individuals in their 60s, 70s, and 80s. However, for people in their 90s, it was explicitly blood pressure variability that posed a more significant risk factor.


This research suggests that rather than high blood pressure alone, it is the variability in blood pressure that may increase the risk of dementia. Notably, this correlation was primarily observed in individuals aged 90 and above, highlighting the importance of maintaining stable blood pressure for the health of the heart and brain in later years.


The study's findings indicate that blood pressure variability may signify an elevated risk of dementia in late life. Still, it may not be as relevant as a target for preventing dementia during midlife.



Strengths And Limitations Of Dementia Study


During the study period, 372 participants developed dementia, with scientists relying on autopsy details and medical records from Kaiser Permanente Washington for their research.


Some experts noted limitations in the study. They suggested that there were limited instances of blood pressure measurement, advocating for more consistent data collection, which could impact medication choices. Factors such as other health conditions and lifestyle elements were not fully considered, which could influence the study outcomes.


However, the study's notable strengths include the availability of more than 30 years of continuous blood pressure data for the same individuals and regular cognitive assessments and dementia confirmation by a specialised committee.


It's worth noting that the study's limitations included the use of autopsy data from consenting participants in the ACT study, a predominantly white participant group with access to high-quality healthcare, and potential variations in the assessors' methods that might have affected blood pressure variability estimates.



Treating Blood Pressure Variability


In 2022, an article explored the treatment of blood pressure variability.


The study found that calcium channel blockers reduced variability while ACE inhibitors, beta-blockers, and alpha-blockers increased it.


The authors suggested that medical professionals should focus on controlling blood pressure without further research.


However, the article considered blood pressure variability concerning cardiovascular disease and the existing research is limited, with no consensus on the treatment approach.


If you need assistance or have questions about your health, you can contact Mobi Doctor for support and guidance.



Blood Pressure Variability and Dementia Risk FAQs

Greater year-to-year systolic blood pressure variability over the preceding decade was associated with a 35% higher dementia risk at age 90. Researchers analysed 820 participants from the Adult Changes in Thought cohort, of whom 372 developed dementia. No significant association appeared at ages 60, 70 or 80, making the finding specific to very late life.

Blood pressure variability describes how much blood pressure changes across repeated measurements. It can refer to minute-to-minute, day-to-day or visit-to-visit fluctuations; this study examined year-by-year systolic readings over ten-year periods. Variability is different from average blood pressure and can be influenced by normal physiology, health conditions, medicines and measurement technique.

Some blood pressure fluctuation is normal because readings respond to movement, stress, sleep, pain, temperature, caffeine and time of day. A single unusual measurement does not establish harmful variability. Repeated readings taken under consistent conditions are more informative, as talking, incorrect posture, an unsuitable cuff or failing to rest beforehand can produce misleading differences.

No. High blood pressure means readings remain consistently above the recommended range, whereas blood pressure variability refers to the size of changes between readings. Someone can have high average pressure with limited variability, normal average pressure with large fluctuations, or both. The study found that mean systolic pressure and variability had different age-related associations with dementia.

The study cannot determine exactly why the association appeared only at age 90. Greater late-life variability could reflect accumulated vascular damage, reduced regulation of blood flow to the brain, medication or illness effects, or early neurodegenerative changes affecting autonomic control. It may therefore be a marker of vulnerability in very late life rather than a direct cause.

No causal relationship has been established between fluctuating blood pressure and dementia. This was an observational study, meaning it identified an association without proving that one factor caused the other. Participants also came from a selected autopsy cohort and were mostly White with relatively good healthcare access, which limits how widely the results can be applied.

Repeated pressure changes could potentially strain small blood vessels, interfere with stable cerebral blood flow or contribute to vascular brain damage. The reverse may also occur: developing neurodegenerative disease could disrupt the body systems that regulate blood pressure. These remain possible explanations, and the study did not directly establish which mechanism produced the observed association.

There is no established treatment aimed specifically at blood pressure variability for dementia prevention. The practical priority is accurate monitoring and good overall blood pressure control. Use a validated upper-arm device, rest quietly for five minutes, keep your feet flat and arm supported, and take two readings about one minute apart. Do not alter prescribed medication without clinical guidance.

Arrange a medical review when large fluctuations recur, readings remain outside your usual range, or changes occur with dizziness, fainting or medication side effects. If blood pressure exceeds 180/120 mm Hg alongside chest pain, breathlessness, weakness, numbness, vision changes or difficulty speaking, call 112 immediately because these symptoms can indicate a hypertensive emergency.


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