JMIR Publications

ABSTRACT

Background:

Cognitive impairment in older adults reduces independence and raises healthcare costs but can be mitigated through stimulating activities. Based on network theory, intricate relationships within and between clusters of Instrumental Activities of Daily Living (IADLs) and cognitive domains suggest the existence of central IADLs and cognitive domains, as well as bridge IADLs. Modifying these can significantly enhance daily living activities and cognitive functions holistically.

Objective:

This study aims to identify central IADLs (key activities within the IADL network), central cognitive domains (key domains within the cognitive network), and bridge IADLs (linking IADL and cognitive networks). These insights will inform targeted interventions to effectively improve IADL and cognitive well-being in older adults.

Methods:

A cross-sectional analysis of adults aged 65 and older in the United States focused on five IADLs and six cognitive domains from the National Health and Aging Trends Study (NHATS). Network analysis identified central and bridge variables. Non-parametric and case-dropping bootstrap methods checked network stability. Network comparison tests assessed sex differences with Benjamini-Hochberg adjustments.

Results:

Of the 2,239 participants, 56.4% were female. We computed and tested three networks: IADL, cognition, and bridge. The Correlation Stability Coefficients for these were 0.67, 0.75, and 0.44 respectively, all exceeding the threshold of 0.25. Meal preparation (centrality: 3.87), visual attention (0.86), and shopping (0.41) were identified as central IADL, central cognition, and bridge IADL respectively, as they had the highest centrality indices and were significantly higher than others in their networks (p < 0.05). Notably, gender differences emerged in the IADL network, with stronger associations between laundry and meal preparation in females (1.69 vs. males: 0.74, p = 0.001) and higher centrality in meal preparation among females (difference = 1.99, p = 0.007).

Conclusions:

While broad enhancements in all IADL and cognitive domains are beneficial, targeting meal preparation, visual attention, and shopping optimizes cost-effectiveness in improving holistic IADL, holistic cognition, and holistic cognition function via IADL interventions among older adults. Notably, meal preparation interventions may be less effective in males, requiring tailored approaches.