Dizziness when standing may indicate heightened dementia risk

Orthostatic hypotension — which can cause dizziness when standing — may indicate an increased risk for developing dementia, according to research published in Neurology, the medical journal of the American Academy of Neurology.

“Orthostatic hypotension (OHYPO) has been associated with an increased risk of cardiovascular events and all-cause mortality but the relationship with cognitive outcomes is less clear,” Laure Rouch, PharmD, PhD, of the department of psychiatry at the University of California, San Francisco, and colleagues wrote.

They noted that their study found that “systolic OHYPO and visit-to-visit variability over time of postural changes in [seated systolic BP] were associated with an increased risk of dementia of almost 40%.”

Rouch and colleagues evaluated 2,131 older adults who participated in the Health, Aging, Body Composition cohort study. Participants had their orthostatic BP assessed multiple times over a 5-year baseline period.

The researchers defined OHYPO as a drop of 15 mmHg or more in systolic BP or 7 mmHg or more in diastolic BP after standing up from a seated position in at least a third of visits.

They determined incident dementia over 12 years of follow up based on patients’ use of dementia medication, a decline in scores on the Modified Mini-Mental State Examination or through hospitalization records.

Rouch and colleagues found that 14.5% of participants had OHYPO, 9% of whom had systolic OHYPO and 6.2% had diastolic OHYPO. Among the participants, 21.7% developed dementia during the study period.

After adjusting for a variety of factors — including demographic information, seated systolic BP (SBP), antihypertensive medications, cerebrovascular disease, BMI, diabetes and smoking — the researchers determined that systolic OHYPO was associated with a nearly 40% increased risk for dementia (adjusted HR = 1.37; 95% CI 1.01-1.88).

According to the researchers, diastolic OHYPO and OHYPO were not significantly associated with risk for incident dementia.

Compared with those with the lowest visit-to-visit variability in SBP postural changes, participants with the highest variability had an increased risk for dementia (adjusted HR = 1.35; 95% CI 1.06-1.71).

“People’s blood pressure when they move from sitting to standing should be monitored,” Rouch said in a press release. “It’s possible that controlling these blood pressure drops could be a promising way to help preserve people’s thinking and memory skills as they age.”

Although the study identified an association between BP readings and developing dementia, it did not determine causation, the researchers noted.