Journal of the American Heart Association reports that a significant drop in systolic blood pressure may indicate imminent likelihood of Alzheimer’s disease or dementia in some elderly people.
A research team from Karolinska Institutet in Stockholm led by professor Laura Fratiglioni, M.D., Ph. D., found that a substantial drop in systolic blood pressure (the higher number in a blood pressure reading) predicted the onset of dementia in people with a systolic pressure of less than 160 millimeters of mercury (mm Hg). A drop in systolic pressure of 15 mm Hg or more was linked to a three-fold increase in the risk of getting Alzheimer’s disease or other dementia.
The same 15 mm Hg or more decrease in patients who already had vascular disorders such as stroke and diabetes mellitus increased their risk of Alzheimer’s 2.4 times, and 2.5 times for all types of dementia.
“Our findings imply that poor blood flow in the brain, resulting from an extensive decline in blood pressure, may promote the dementia process,” said lead author Chengxuan Qiu, M.D., a postdoctoral epidemiologist at the Karolinska Institutet.
However, because so few studies have addressed the connection between blood pressure decline and dementia, these findings need further verification. “Indeed, we have to consider that patients with dementia experience a decline in blood pressure some years before diagnosis, which continues to decline after the onset of dementia,” Fratiglioni said.
Alzheimer’s disease is the most common cause of dementia in Western countries. Other causes include repeated strokes and secondary dementia resulting from neurological disorders such as Parkinson’s disease.
This study aimed to verify blood pressure variations before and after dementia diagnosis, and to investigate whether blood pressure decline was predictive of Alzheimer’s disease and dementia.