A condition called orthostatic hypotension occurs when people experience dizziness when standing up due to a sudden drop in blood pressure. New research shows that adults who experience dizziness or lightheadedness in such cases are at increased risk of developing dementia years later. However, the study found that theAssociation with dementiaonly exists in people who have a drop in their systolic blood pressure.
Why does dizziness occur when standing up?
The highest number in a blood pressure measurement is systolic orthostatic hypotension. This occurs as a drop of at least 15 mmHg after rising from a sitting position. People's blood pressure as they transition from sitting to standing can provide clues to this condition. Additionally, controlling these drops in blood pressure could be a promising way to preserve thinking and memory skills as we age. 2,131 people, who were on average 73 years old, took part in the study. At enrollment, the subjects did not have dementia. Researchers measured their blood pressure levels at the start of the study and then one, three and five years later. A total of 15% had orthostatic hypotension, 9% had systolic orthostatic hypotension, and 6% had diastolic orthostatic hypotension. Over the next 12 years, participants were screened to determine whether anyone had dementia. A total of 462 people, or 22%, then developed the disease.
People with systolic orthostatic hypotension were 40% more likely to develop dementia than the rest of the subjects. Fifty of the 192 patients with systolic orthostatic hypotension, or 26%, developed dementia. The researchers compared this with 412 of the 1,939 people or 21% of healthy people. Then they adjusted for other factors that might influence the risk of dementia. These were, for example, diabetes, smoking and alcohol consumption. The likelihood of dementia in patients with systolic orthostatic hypotension then increased by 37%. The researchers also found that people whose systolic blood pressure changed the most from sitting to standing from visit to visit were more likely to develop dementia years later than people whose readings were more stable.
More results
Whileof the studyThe research team divided participants into three groups based on how much their measurements changed over time. A total of 24% of people in the group with the greatest variation in systolic values later developed dementia. The team compared this with 19% of the people in the group with the lowest fluctuation. When researchers took into account other factors that influence dementia risk, those in the highest group were 35% more likely to develop dementia than those in the lowest group. However, they also noted that the study is observational and does not show cause and effect. The results therefore only show a connection between dizziness when standing up with the resulting blood pressure values and the development of dementia. Another limitation of the study was that the diagnosis of dementia was made without distinguishing between Alzheimer's disease andvascular dementiawas provided.
