Higher fluctuation in blood pressure is linked to faster decline in brain function, a new study has found.
Specifically, changes in BP readings in a span of long-term periods were connected to the degradation in cognitive abilities among the elderly population. The researchers came up with this idea as blood pressure changes may indicate instability in blood flow, which could result in injuries of tiny blood vessels, with alterations in the form and operation of the brain.
"These blood pressure fluctuations may indicate pathological processes such as inflammation and impaired function in the blood vessels themselves," says lead study author Bo Qin from Rutgers Cancer Institute.
Investigating Effects Of Variable BP To Brain Function
For the study, the team looked into data from 976 Chinese adults, of which 50 percent were women and were aged 55 years old and above. The participants are all included in the China Health and Nutrition Survey for half a decade.
Changes in blood pressure were determined from three to four health consultations. The subjects also answered quizzes such as word recall test and counting backwards.
Findings show that higher fluctuation rates of systolic BP (the upper number in BP readings) visit-per-visit were linked to a more rapid drop in cognition and verbal memory.
Higher variability of diastolic BP (lower number in BP readings) was also linked to faster drop in cognition, but only among those aged 55 to 64 years old only.
Both average systolic or diastolic blood pressure did not establish a relationship with brain changes.
Fresh Perspective
Doctors have been looking at average BP readings when checking their patients. Qin says, maybe it is time for them to also consider high BP fluctuations as well. She adds that manipulating blood pressure variability may be a possible preventive measure in preserving cognition in older adults.
Although the research was based on observation and that there was no direct cause and effect relationship established, it still adds to the growing data that BP variability may signify a higher risk for other medical problems. More long-term and clinical trials are necessary to verify the study results.
The study was published (PDF) in the journal Hypertension of the American Heart Association on May 23.