Impact of Cognitive Frailty on Daily Activities in Older Persons

Abstract

Objectives: To identify the relationships between physical and/or cognitive frailty and instrumental activities of daily living (IADL) functioning in community living older persons.

Design: Cross sectional observation study.

Setting: Data extracted from the 2011-2013 of the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes (NCGG-SGS) database.

Participants: A total of 8,864 older adults aged ≥ 65 years who were enrolled in the NCGG-SGS.

Measurements: We characterized physical frailty as limitations in three or more of the following five domains: slow walking speed, muscle weakness, exhaustion, low activity and weight loss. To screen for cognitive impairment, we used the National Center for Geriatrics and Gerontology-Functional Assessment Tool (NCGG-FAT) which included tests of word list memory, attention and executive function (tablet version of the Trail Making Test, part A and B), and processing speed (tablet version of the Digit Symbol Substitution Test). Two or more cognitive impairments indicated by an age-adjusted score of at least 1.5 standard deviations below the reference threshold was characterized as cognitive impairment. Each participant reported on their IADL status (use of public transportation, shopping, management of finances, and housekeeping) and several potential confounders such as demographic characteristics.

Results: The overall prevalence of physical frailty, cognitive impairment, and cognitive frailty, i.e. co-occurrence of frailty and cognitive impairment, was 7.2%, 5.2%, and 1.2%, respectively. We found significant relationships between IADL limitations and physical frailty (Odds Ratio (OR) 1.24, 95% confidence interval (95% CI) 1.01 to 1.52), cognitive impairment (OR 1.71, 95% CI 1.39 to 2.11), and cognitive frailty (OR 2.63, 95% CI 1.74 to 3.97).

Conclusion: Using the NCGG-SGS frailty criteria, we found more participants with physical frailty than with cognitive frailty. The individuals with cognitive frailty had the highest risks of IADL limitations. Future investigation is necessary to determine whether this population is at increased risk for incidence of disability or mortality.