"Blood pressure variability might signal blood flow instability, which could lead to the damage of the finer vessels of the body with changes in brain structure and function," said Bo Qin from Rutgers Cancer Institute in the US.

"These blood pressure fluctuations may indicate pathological processes such as inflammation and impaired function in the blood vessels themselves," said Qin.

Researchers analysed results from 976 Chinese adults (half women, age 55 and or older) who participated in the China Health and Nutrition Survey over a period of five years.

Blood pressure variability was calculated from three or four visits to a health professional. Participants also underwent a series of cognitive quizzes such as performing word recall and counting backwards, researchers said.

They found that higher visit-to-visit variability in the top number in a blood pressure reading (systolic blood pressure) was associated with a faster decline of cognitive function and verbal memory.

Researchers also found that higher visit-to-visit variability in the bottom number (diastolic  blood pressure) was associated with faster decline of cognitive function among adults aged 55 to 64, but not among those aged 65 and older.

Neither average systolic or diastolic blood pressure readings were associated with brain function changes, researchers said.

Physicians tend to focus on average blood pressure readings, but high variability may be something for them to watch for in their patients, they said.

"Controlling blood pressure instability could possibly be a potential strategy in preserving cognitive function among older adults," said Qin.

The findings add to a growing body of evidence that variation in blood pressure readings - perhaps more so than averages - may indicate increased risk for some additional health problems, researchers said.

The findings were published in the journal Hypertension.

Latest News from Lifestyle News Desk