The risk of cognitive loss and mild cognitive impairment in women is significantly associated with uncontrolled high blood pressure, according to research published in January 2022 in the journal The Lancet Health Longevity.
These risks were found to be tied to elevated levels of systolic blood pressure (SBP), the top number in a pressure screening, and with high levels of pulse pressure (PP). PP is the difference between an individual’s systolic and diastolic (bottom) pressure readings.
“Overall, an increase in every 10 mm Hg of SBP was associated with a 5% increased risk of cognitive loss, and a 4% increased risk of mild cognitive impairment. An increase in every 10 mm Hg of PP was associated with a 7% increased risk of cognitive loss and of mild cognitive impairment,” said the Lancet paper.
Researcher Longjian Liu and his co-authors analyzed a sample of 7,207 community-dwelling women aged 65–79 years who participated in the Women’s Health Initiative Memory Study (WHIMS).
Older women whose high blood pressure was being treated and controlled — to SBP lower than 120 mg HG or to PP less than 50 MB HG — did not have elevated risk of cognitive loss and mild cognitive impairment. “These results add new evidence that decreased SBP and PP levels might have a pivotal role in preserving cognitive health in older women,” wrote Liu and his co-authors.
In the meantime, “Evidence on whether controlled SBP at less than 120 mm HG or PP at less than 50 mm HG are associated with risk reduction of probably dementia remains uncertain,” wrote the authors. However, they added, “This lack of evidence is probably due to a small sample size of those with diagnosed probably dementia.”
According to the researchers, high blood pressure and elevated SBP and PP could lead to cognitive impairment in a number of ways, including heart attack, heart failure, stroke, peripheral arterial disease and atrial fibrillation.
They also noted, “studies have shown a significant association between increased BP and white matter abnormalities, suggesting that elevated BP might play a role in the pathogenesis of cognitive impairment by affecting the development of neuropathological lesions or brain atrophy.”
The study had several limitations, noted the researchers. First, blood pressure data was limited to older women (age 65-plus), and second, most of the study participants were White. So, the results may not apply to younger women and other racial and ethnic groups, said the researchers. They did note that other studies have shown a link between higher systolic blood pressure in one’s 50s and increased risk of dementia later in life.
Lancet Health Longevity, a multi-disciplinary journal, publishes clinically-focused longevity and healthy-aging research and reviews.