Prospective memory partially mediates the association between aging and everyday functioning

Abstract

Objective: Older adults commonly experience declines in everyday functioning, the reasons for which are multifactorial. Prospective memory (PM), or remembering to carry out intended actions, can be an executively demanding cognitive process that declines with older age and is independently associated with a variety of everyday functions (e.g. taking medication). This study examined the hypothesis that PM mediates the relationship between older age and poorer everyday functioning.

Method: A total of 468 community-dwelling adults (ages 18–75) with a range of medical comorbidities (e.g. viral infection) were classified as dependent on four well-validated measures of manifest everyday functioning: activities of daily living, employment status, the Karnofsky Scale of Performance Status, and self-reported cognitive symptoms. Participants completed the Memory for Intentions Test (MIsT) to measure PM, alongside clinical tests of executive functions and retrospective memory.

Results: Controlling for education and comorbidities, bootstrap analysis revealed a significant direct effect of age on everyday functioning and a significant mediated effect of age on everyday functioning through the indirect effect of time-based b = .006 [.003, .010] and event-based PM (b = .005, [.002, .009]), as well as slightly smaller effects for executive functions (b = .003, [.001, .005]) and retrospective memory (b = .002, [.001, .005]).

Conclusions: These cross-sectional data suggest that executively demanding aspects of declarative memory play an important partial mediating role between an individual factor (i.e. age) and daily life activities, and highlight the possible benefit of targeting PM for improving everyday functioning in older adults.

Keywords:

• Mediation
• older adults
• cognition
• executive functions
• activities of daily living

Acknowledgements

The authors are grateful to the UC San Diego HIV Neurobehavioral Research Program (HNRP) Group (I. Grant, PI) for their infrastructure support of the parent R01. In particular, we thank Donald Franklin, Dr. Erin Morgan, Clint Cushman, and Stephanie Corkran for their assistance with data processing, Marizela Verduzco for managing the studies, Drs. Scott Letendre and Ronald J. Ellis for their assistance with the neuromedical aspects of the parent project, and Dr. J. Hampton Atkinson and Jennifer Marquie Beck and their assistance with participant recruitment and retention. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of Defense, nor the United States Government. The authors thank the study volunteers for their participation. Aspects of these data have been included in other studies from our group (see Avci et al. (2018) for a review) and were presented at the Annual Meeting of the Houston Neuropsychological Society.

Disclosure statement

The authors have no financial conflicts of interest related to this work.

Funding

This study was supported by NIH grants R01-MH073419 and P30-MH62512.