Researchers at the University of California, San Diego and Veterans Affairs San Diego Healthcare System have shown that elevated pulse pressure may increase the risk of cerebrovascular disease (CVD) in older adults with Alzheimer's disease (AD). Their study has been published in the early online edition of Journal of Alzheimer's Disease in advance of the June 5 print publication.
The findings may have treatment implications, since some antihypertensive medications specifically address the pulsatile component of blood pressure. Pulse pressure (PP) - the difference between systolic and diastolic pressure - is one measure of the pulsatile component of blood pressure. PP increases substantially with age, partially due to hardening of the arteries.
Hypertension is a common risk factor for AD, but the use of antihypertensive medications to prevent dementia has had mixed results. Most studies examining the effects of blood pressure on the risk of AD have focused on standard measures of blood pressure, the systole and diastole readings. However, scientists theorized that PP elevation may impair the clearance of beta amyloid - a hallmark of AD - from the brain. Other studies have suggested that PP elevation may contribute to AD risk indirectly by increasing the risk of CVD.
The researchers, led by Mark W. Bondi, PhD, of VA San Diego Healthcare System and UC San Diego Department of Psychiatry, looked at 65 patients who later met the criteria for AD at autopsy. These patients were examined before death for relationships among blood pressure and neuropathologic markers. More than half of them were found, at autopsy, to have CVD.