New research has suggested that middle-aged people who have high pulse pressure - a measure of high blood pressure - are more likely to have biomarkers of Alzheimer's disease in their spinal fluid, compared with people who have lower pulse pressure.
According to the Mayo Clinic, a high pulse pressure could be a strong indicator of heart problems, particularly for older adults.
Researchers from the VA San Diego Healthcare System analyzed 177 people aged between 55 and 100 who had no symptoms of Alzheimer's disease.
All participants had their blood pressure recorded and underwent lumbar punctures in order for the researchers to obtain spinal fluid.
The study findings, published in the journal Neurology, revealed that patients aged between 55 and 70 who had a higher pulse pressure were more likely to have biomarkers of Alzheimer's disease in their cerebral spinal fluid, compared with those who had lower pulse pressure.
The Alzheimer's biomarkers discovered were:
- Beta amyloid plaques - clusters of protein fragments that build up between nerve cells.
- P-tau protein - defected protein that can no longer stabilize microtubules.
- Tangles - twisted strands of protein in dead and dying nerve cells.
The investigators found that for every 10 point increase in pulse pressure, the average level of P-tau protein in the spinal fluid rose by 1.5 picograms per millimeter (1 picogram is the equivalent to 1 trillionth of a gram).
Explaining the findings, Daniel A. Nation, of the VA San Diego Healthcare System and study author, says:
"These results suggest that the forces involved in blood circulation may be related to the development of the hallmark Alzheimer's disease signs that cause loss of brain cells."
Interestingly, he notes the relationship between high pulse pressure and Alzheimer's disease was only found in people aged between 55 and 70.
"This is consistent with findings indicating that high blood pressure in middle age is a better predictor of later problems with memory and thinking skills and loss of brain cells than high blood pressure in old age," he says.
Medical News Today recently reported on a study detailing the discovery of biological mechanisms that may link Alzheimer's and Parkinson's disease, while other research detailed the creation of a new cognitive model that could detect early stage dementia.