Affiliations: [a] Department of Psychology, University of Southern California, Los Angeles, CA, USA
| [b] Department of Psychological Science, University of California, Irvine, Irvine, CA, USA
| [c] Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, USA
Correspondence:
[*]
Correspondence to: Daniel A. Nation, PhD, Associate Professor, University of California Irvine, Department of Psychological Science, 4201 Social and Behavioral Sciences Gateway, Irvine, CA 92697-7085, USA. Tel.: +1 949 824 9339; E-mail: dnation@uci.edu.
Note: [1] Data used in preparation of this article were obtained from
the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database
(https://adni.loni.usc.edu). As such, the investigators within the
ADNI contributed to the design and implementation of ADNI
and/or provided data but did not participate in analysis or writing
of this report. A complete listing of ADNI investigators can
be found at: https://adni.loni.usc.edu/wp-content/uploads/how_to_apply/ADNI_Acknowledgement_List.pdf.
Abstract: Background:Elevated blood pressure is linked to cognitive impairment and Alzheimer’s disease (AD) biomarker abnormality. However, blood pressure levels vary over time. Less is known about the role of long-term blood pressure variability in cognitive impairment and AD pathophysiology. Objective:Determine whether long-term blood pressure variability is elevated across the clinical and biomarker spectrum of AD. Methods:Alzheimer’s Disease Neuroimaging Initiative participants (cognitively normal, mild cognitive impairment, AD [n = 1,421]) underwent baseline exam, including blood pressure measurement at 0, 6, and 12 months. A subset (n = 318) underwent baseline lumbar puncture to determine cerebrospinal fluid amyloid-β and phosphorylated tau levels. Clinical groups and biomarker-confirmed AD groups were compared on blood pressure variability over 12 months. Results:Systolic blood pressure variability was elevated in clinically diagnosed AD dementia (VIM: F2,1195 = 6.657, p = 0.001, η2 = 0.01) compared to cognitively normal participants (p = 0.001), and in mild cognitive impairment relative to cognitively normal participants (p = 0.01). Findings were maintained in biomarker-confirmed AD (VIM: F2,850 = 5.216, p = 0.006, η2 = 0.01), such that systolic blood pressure variability was elevated in biomarker-confirmed dementia due to AD relative to cognitively normal participants (p = 0.005) and in biomarker-confirmed mild cognitive impairment due to AD compared to cognitively normal participants (p = 0.04). Conclusion:Long-term systolic blood pressure variability is elevated in cognitive impairment due to AD. Blood pressure variability may represent an understudied aspect of vascular dysfunction in AD with potential clinical implications.
Keywords: Alzheimer’s disease, amyloid, blood pressure, cognitive dysfunction, tau
proteins
