The relationship of longitudinal cognitive change to self-reported IADL in a general population

ABSTRACT

This study examined the relationship between cognitive change and instrumental activities of daily living (IADL) in a large, national, population-based sample. Cognitive change was assessed via verbal fluency, word list learning (WLL), and word list delayed recall (WLD). Incident cognitive impairment was defined by change in Six-Item Screener (SIS) status over a period of 10 years. Impaired IADL was defined as self-reported difficulty or needing assistance performing any IADL at Year 10. A one-word decrease in WLL over a 10-year span increased the odds of impaired IADL by 16% (95% CI 1.08–1.24) and incident cognitive impairment increased the odds of impaired IADL by 59% (95% CI 1.36–1.85) when adjusting for demographic factors, health-related behaviors, vascular risk factors and disease, and depressive symptoms. Cognitive change most strongly predicted impairment in managing finances (OR 2.47, 95% CI 2.04–3.00) and driving (OR 2.06, 95% CI 1.73–2.44).

KEYWORDS:

• Cognitive aging
• depression
• instrumental activities of daily living
• longitudinal studies
• stroke

Acknowledgments

The REGARDS research project is supported by a cooperative agreement U01 NS041588 from the National Institute of Neurological Disorders and Stroke, National Institutes of Health, Department of Health and Human Service. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Neurological Disorders and Stroke or the National Institutes of Health. Representatives of the funding agency have been involved in the review of the manuscript but not directly involved in the collection, management, analysis or interpretation of the data. The authors thank the other investigators, the staff, and the participants of the REGARDS study for their valuable contributions. A full list of participating REGARDS investigators and institutions can be found at http://www.regardsstudy.org.

Author’s contributions

Study concept and design (Passler, Kennedy, Clay, Crowe, Howard, Cushman, Unverzagt, Wadley); Acquisition of subjects and/or data (Passler, Howard, Wadley); Analysis/interpretation of data (Passler, Kennedy, Wadley); Preparation of manuscript (Passler, Kennedy, Clay, Crowe, Howard, Cushman, Unverzagt, Wadley).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported in part by National Institute on Aging [P30AG022838]; National Center for Advancing Translational Sciences [UL1TR00165]; National Institute of Neurological Disorders and Stroke [U01 NS041588].