High or low blood pressure can be bad news for health, but mounting evidence suggests blood pressure variation could also be a problem. New research has linked variation in blood pressure readings with worse mental function in older adults.
The study comes from Bo Qin, Ph.D. of Rutgers Cancer Institute in New Brunswick, New Jersey, and other researchers, who posted their results in the American Heart Association journal Hypertension. The researchers studied 976 Chinese men and women, aged 55 and older, enrolled in the China Health and Nutrition Survey. The study lasted five years, with three or four doctors visits, and involved measuring blood pressure and performing cognitive quizzes, such as recalling words or counting backwards.
Doctors usually note a patient’s average systolic or diastolic blood pressure readings to determine whether they have high or low blood pressure, then treat the patient accordingly. The researchers discovered these average readings did not seem to be associated with changes in brain function in the study participants.
However, the researchers did find a link between variability in systolic blood pressure from visit to visit and a faster cognitive function decline and decline in verbal memory, such as remembering words. For diastolic blood pressure, study participants between ages 55 and 64 experienced a faster cognitive decline when there was higher variability from visit to visit. It seems that, in general, more variability in blood pressure is linked to worse mental function.
The researchers thought that the blood pressure variation could be because of blood flow instability which could then damage blood vessels. This could cause problems with blood vessels in the brain, leading to cognitive difficulties. However, the study did not discover why there was a link or even that variation in blood pressure causes cognitive decline. The research does, however, add to other evidence that blood pressure variation, not average blood pressure readings, could mean an increased risk for various health problems. A 2015 study had already linked blood pressure fluctuation with an increased risk of heart disease and death.
The researchers believe their results could be important for physicians. Instead of focusing on average blood pressure readings, doctors who note variation in blood pressure may discover some older patients who are more at risk for cognitive decline. They could then focus on treatments and lifestyle interventions that help stabilize blood pressure for these at-risk patients.
Blood pressure readings include two numbers, the systolic blood pressure and diastolic blood pressure. A normal blood pressure reading could be 120/80 mm Hg, for example, indicating 120 systolic and 80 diastolic blood pressure. Systolic blood pressure is the pressure at which the heart pumps blood out and diastolic blood pressure is the pressure from the heart filling with blood. 140/90 mm Hg or higher is classed as high blood pressure, with an increased risk of heart disease, heart attack, and stroke, along with other health problems. Although high blood pressure is a concern, more research is discovering blood pressure that fluctuates could lead to health problems as well. Fluctuating blood pressure can be harder for doctors to detect than high blood pressure because it requires multiple readings to see the pattern.
Although doctors may prescribe drugs to help regulate blood pressure, some lifestyle interventions can help as well. Like many health conditions, achieving a healthier weight and exercising regularly can help improve blood pressure. Eating healthier, including eating the right amount of sodium, not too much and not too little, can help regulate blood pressure as well. Quitting smoking, reducing alcohol consumption, and reducing caffeine intake can help lower blood pressure. Trying to reduce stress and keeping calm can also help maintain more even blood pressure levels throughout the day.