Age- and Time-Varying Associations Between Subjective Health and Episodic Memory in Older Adults

Abstract

Objectives: There are positive correlations between subjective health reports and episodic memory performance in older adults. However, previous studies have not evaluated the scope of such complex relationships, nor the potentially nonlinear magnitude of these correlations across age and time. We employed multiple subjective heath indices to evaluate the scope and nonlinearity of such relationships with memory performance.

Methods: We utilized a cross-sectional (N = 2,783 at baseline) and longitudinal sample (N = 311) of healthy older adults aged 65 and older from the Advanced Cognitive Training for Independent and Vital Elderly study. We used time-varying effects modeling (TVEM) to assess potential differences in relationship magnitudes between memory and 3 subjective health subscales (general health, role physical function, and physical function, from the Short Form Health Survey) across 5 years.

Results: Episodic memory positively predicted all subjective health measures cross-sectionally and longitudinally in our sample. TVEM revealed the relationships between all subjective health measures and episodic memory were stable across age. While role physical function and physical function maintained stable relationships with episodic memory across time, general health became increasingly coupled with memory 5 years following baseline.

Discussion: Together, our findings highlight stable and varying relationships between episodic memory and multiple subjective health indicators across metrics of time in older adults. Clinical Trials Registration Number: NCT00298558.

Keywords: Episodic memory; Subjective health; Subjective physical function; TVEM.

© The Author(s) 2021. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Figures

Figure 1.

Coefficient curve of episodic memory composite on (A) general health, (B) role physical function, and (C) physical function across age. Models are adjusted for race, sex, and education. The solid line represents the coefficient estimate and the light gray band represents the 95% confidence interval. Dashed lines represent the 95% confidence interval for older adults aged 85+ years old. Areas where the dashed lines intersect the gray band indicate the magnitude for that age group is not significantly different from the 85+-year-olds (p > .05). Areas where the coefficient band intersects x = 0 indicate a nonsignificant relationship (p > .05). Larger estimate scores indicate greater coefficient magnitude.

Figure 2.

Coefficient curve of episodic memory composite on (A) general health, (B) role physical function, and (C) physical function across time following baseline assessment. Models are adjusted for race, sex, and education. The solid line represents the coefficient estimate and the light gray band represents the 95% confidence interval. Dashed lines represent the 95% confidence interval for 6 years following baseline. Areas where the dashed lines intersect the gray band indicate the magnitude for that time is not significantly different from 6 years following baseline (p > .05). Areas where the coefficient band intersects x = 0 indicate a nonsignificant relationship (p > .05). Larger estimate scores indicate greater coefficient magnitude.