Individuals who feel faint, dizzy or lightheaded just after standing up may be experiencing a sudden drop in blood pressure, a condition known as orthostatic hypotension.
Now a new study published in the journal Neurology suggests that middle-aged people who experience such a drop may have a 54 percent increased risk of developing dementia or stroke in later life.
“Orthostatic hypotension has been linked to heart disease, fainting and falls, so we wanted to conduct a large study to determine if this form of low blood pressure was also linked to problems in the brain, specifically dementia,” said study author Andreea Rawlings, Ph.D., M.S., of Johns Hopkins Bloomberg School of Public Health in Baltimore, Md.
The study involved 11,709 people (average age of 54) who were tracked for an average of 25 years. Participants met with researchers up to five times over the course of the study. None had a history of heart disease or stroke at the onset of the study.
At the first exam, participants were screened for orthostatic hypotension. They were asked to lie down for 20 minutes and then stand up in a smooth, swift motion. Blood pressure was taken five times upon standing.
Researchers calculated the average of the readings and then subtracted the difference from the participant’s average resting blood pressure. The results show that 552 participants, or 4.7 percent, had orthostatic hypotension at the beginning of the study.
Researchers monitored the subjects for dementia and stroke with study visits and by reviewing medical records. During the study, 1,068 people developed dementia and 842 people had an ischemic stroke, which is a stroke where blood flow is blocked to part of the brain.
The findings show that participants who had orthostatic hypotension at the beginning of the study had a 54 percent higher risk of developing dementia than those who did not have orthostatic hypotension at the beginning of the study.
A total of 999 of the 11,156 without orthostatic hypotension, or 9 percent, developed dementia, compared to 69 of the 552 people with orthostatic hypotension, or 12.5 percent.
Furthermore, those with orthostatic hypotension had double the risk of ischemic stroke. A total of 15.2 percent, or 84 of 552 people, with orthostatic hypotension had an ischemic stroke, compared to 6.8 percent, or 758 of 11,157 people without orthostatic hypotension. There was no link found with bleeding strokes.
“Measuring orthostatic hypotension in middle-age may be a new way to identify people who need to be carefully monitored for dementia or stroke,” said Rawlings. “More studies are needed to clarify what may be causing these links as well as to investigate possible prevention strategies.”
Source: American Academy of Neurology