People who feel faint, dizzy or lightheaded when standing up may be experiencing a sudden drop in blood pressure called orthostatic hypotension. Now a new study says middle-aged people who experience such a drop may have a greater risk of developing dementia or stroke decades later. The study is published in the July 25 online issue of Neurology, the medical journal of the American Academy of Neurology.
“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 Dr. Andreea Rawlings, of Johns Hopkins Bloomberg School of Public Health.
For this study, low blood pressure upon standing was defined as a drop of at least 20 millimeters of mercury (mmHg) in systolic blood pressure, which is the pressure in the blood vessels when the heart beats, or at least 10 mmHg in diastolic blood pressure, the pressure when the heart is at rest. Normal blood pressure is less than 120/80 mmHg.
Researchers found those 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.