Blood pressure variability and plasma Alzheimer’s disease biomarkers in older adults

Blood pressure variability is an emerging risk factor for Alzheimer’s disease in older adults, independent of average blood pressure levels. Growing evidence suggests increased blood pressure variability is linked to Alzheimer’s disease pathophysiology indexed by cerebrospinal fluid and positron emission tomography markers, but relationships with plasma Alzheimer’s disease markers have not been investigated. In this cross-sectional study of 54 community-dwelling older adults (aged 55–88, mean age 69.9 [8.2 SD]), elevated blood pressure variability over 5 min was associated with lower levels of plasma Aβ 1–42 (standardized ß = − 0.36 [95% CI − 0.61, − 0.12]; p = 0.005; adjusted R 2 = 0.28) and Aβ 1–42 : Aβ 1–40 ratio (ß = − 0.49 [95% CI − 0.71, − 0.22]; p < 0.001; adjusted R 2 = 0.28), and higher levels of total tau (ß = 0.27 [95% CI 0.01, 0.54]; p = 0.04; adjusted R 2 = 0.19) and Ptau 181 :Aβ 1–42 ratio (ß = 0.26 [95% CI 0.02, 0.51]; p = 0.04; adjusted R 2 = 0.22). Findings suggest higher blood pressure variability is linked to plasma biomarkers of increased Alzheimer’s disease pathophysiology.