Right hippocampal volume mediation of subjective memory complaints differs by hypertension status in healthy aging

Emily J Van Etten; Pradyumna K Bharadwaj; Lauren A Nguyen; Georg A Hishaw; Theodore P Trouard; Gene E Alexander

doi:10.1016/j.neurobiolaging.2020.06.012

Right hippocampal volume mediation of subjective memory complaints differs by hypertension status in healthy aging

Neurobiol Aging. 2020 Oct:94:271-280. doi: 10.1016/j.neurobiolaging.2020.06.012. Epub 2020 Jun 19.

Authors

Emily J Van Etten¹, Pradyumna K Bharadwaj¹, Lauren A Nguyen¹, Georg A Hishaw², Theodore P Trouard³, Gene E Alexander⁴

Affiliations

¹ Department of Psychology, University of Arizona, Tucson, AZ, USA; Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, USA.
² Department of Neurology, University of Arizona, Tucson, AZ, USA.
³ Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, USA; Department of Biomedical Engineering, University of Arizona, Tucson, AZ, USA; Arizona Alzheimer's Consortium, Phoenix, AZ, USA.
⁴ Department of Psychology, University of Arizona, Tucson, AZ, USA; Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, USA; Arizona Alzheimer's Consortium, Phoenix, AZ, USA; Department of Psychiatry, University of Arizona, Tucson, AZ, USA; Neuroscience Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA; Physiological Sciences Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA. Electronic address: gene.alexander@arizona.edu.

PMID: 32688134
PMCID: PMC9119497
DOI: 10.1016/j.neurobiolaging.2020.06.012

Abstract

Subjective memory complaints (SMCs) may be an important early indicator of cognitive aging and preclinical Alzheimer's disease risk. This study investigated whether age-related differences in right or left hippocampal volume underlie SMCs, if these relationships differ by hypertension status, and how they are related to objective memory performance in a group of 190 healthy older adults, 50-89 years of age. Analyses revealed a significant mediation of the relationship between age and mild SMCs by right hippocampal volume that was moderated by hypertension status. This moderated mediation effect was not observed with left hippocampal volume. Additionally, a moderated serial mediation model showed that age predicted right hippocampal volume, which predicted SMCs, and in turn predicted objective memory performance on several measures of verbal selective reminding in individuals with hypertension, but not in non-hypertensives. Together, these findings suggest that even mild SMCs, in the context of hypertension, provide an early indicator of cognitive aging, reflecting a potential link among vascular risk, SMCs, and the preclinical risk for Alzheimer's disease.

Keywords: Cognitive aging; Hippocampal volume; Hypertension; Memory; Preclinical Alzheimer’s disease risk; Subjective memory decline.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Age Factors
Aged
Aged, 80 and over
Alzheimer Disease / etiology
Cognitive Aging / psychology*
Female
Healthy Aging / pathology*
Healthy Aging / psychology*
Hippocampus / pathology*
Humans
Hypertension / pathology*
Hypertension / psychology*
Male
Memory Disorders / etiology*
Memory Disorders / psychology
Memory*
Middle Aged
Organ Size
Risk

Abstract

Publication types

MeSH terms

Grants and funding