An early warning sign of developing Alzheimer's disease is a drop in blood pressure, say researchers, according to new research.
Results from previous research on the association between blood pressure and Alzheimer's disease have been conflicting. In a recent study, researchers focused on blood pressure variations before and after a diagnosis of dementia.
The research included 947 patients who were 75 or older. The participants had no signs of dementia when they started the study. They had their blood pressure taken and physical examinations at the start of the study and again three and six years later.
Results showed that 147 of the patients were diagnosed with Alzheimer's disease and 39 with dementia at the three-year follow up. At six years, another 91 people were diagnosed with Alzheimer's disease and 27 with dementia. When looking at blood pressure, researchers say those who had a drop of 15 millimeters of mercury in systolic blood pressure (the higher number in a blood pressure reading) were at an increased risk for getting Alzheimer's disease or dementia. This was true in patients who had a systolic pressure of less than 160 millimeters of mercury at the start of the study or who had other vascular disorders.
Thus researchers say that their findings imply that poor blood flow in the brain, resulting from an extensive decline in blood pressure, may promote the dementia process .