Middle-Age Blood Pressure May Predict Alzheimer’s Disease

Pulse pressure is the systolic pressure, or the top number in a blood pressure reading, minus the diastolic, or the bottom number. Pulse pressure increases with age and is an index of the aging of the vascular system. Daniel A. Nation, from the VA San Diego Healthcare System (California, USA), and colleagues studied 177 men and women, ages 65 to 100 years, who did not show symptoms of Alzheimer's disease at the study’s start.  Participants had their pulse pressure taken and lumbar punctures to obtain spinal fluid.  The researchers found that people who have higher pulse pressure are more likely to have the Alzheimer's biomarkers amyloid beta, or plaques, and p-tau protein, or tangles, in their cerebral spinal fluid than those with lower pulse pressure. For every 10 point rise in pulse pressure, the average level of p-tau protein in the spinal fluid rose by 1.5 picograms per milliliter. The relationship was found in people age 55 to 70, but not in people age 70 to 100. Writing that: "[Pulse pressure] elevation is associated with increased [cerebrospinal fluid] P-tau and decreased A[beta]1-42 in cognitively normal older adults,” the study authors submit that: "pulsatile hemodynamics may be related to amyloidosis and tau-related neurodegeneration. “