Disability Measurement in the Health and Retirement Study

A functional approach to model intrinsic capacity in ageing trajectories

The ageing process is a multifaceted phenomenon that affects individuals' physical, cognitive, and psychological well-being over time. To promote healthy ageing, in the mid-2010s, the World Health Organisation introduced the concept of intrinsic capacity (IC) as the set of physical and mental capacities of an individual. These capacities, categorised into five domains, namely cognition, vitality, locomotion, psychological well-being, and sensory, are assessed by healthcare practitioners using the ICOPE guidelines, a laborious and time-consuming task. This study leverages existing data from longitudinal studies, such as the well-known Health and Retirement Study, to align their dimensions with the ICOPE framework and understand how existing ageing trajectories fit within the new IC paradigm. Moreover, a novel IC scoring system has been validated statistically using linear mixed models, and a simple yet comprehensive data visualisation strategy has been designed to illustrate IC trajectories. Results show the significant negative impact of time on all IC domains, except psychological well-being, showing a gradual IC decline over the years. Additionally, significant associations between lifestyle factors, such as physical activity, alcohol and tobacco consumption, and body mass index, with IC trajectories have been identified. This work suggests the feasibility of using existing longitudinal studies to quantitatively model IC ageing trajectories following the ICOPE framework.

Capturing multiple assistive technology use and its impact in later life: lessons learned from distinct measurement approaches

PURPOSE

Assistive technology (AT) use is prevalent in older adulthood and can accommodate activity difficulties to support well-being. However, within the context of multiple activity difficulties and multiple technology use, it is unclear how to best assess their combined effects on older adults' health outcomes. This study proposed four distinct approaches to quantify multiple AT use and examined their respective impact in later life.

MATERIAL AND METHODS

Using data from the 2015 round of the National Health and Aging Trends Study (n = 6,936), we compared four indices to summarize the state of multiple AT use among the U.S. older population: binary, item-specific, cumulative, and accommodative. Separate regression analyses tested the impact of each index on older adults' well-being and restricted participation in meaningful activities.

RESULTS

In 2015, 59.9% of the respondents were identified as AT users. Among these users, 53.8% reported using two or more technologies when performing daily self-care and mobility activities. The implications of multiple AT use for health outcomes varied across the four indices. Approaches that captured elements of person-technology fit provided the most nuanced and actionable insights on the benefits of using AT to support well-being.

CONCLUSIONS

ATs were commonly adopted by older adults in everyday activities. Overall, findings suggest that there are multiple approaches to conceptualize the independent, cumulative, or balanced effects of multiple AT use. Each measurement approach has unique implications for understanding the impacts of using ATs on older adults' health outcomes.

Revisiting the caregiver stress process: Does family caregiving really lead to worse mental health outcomes?

While the act of caregiving is often characterized as a stressful experience detrimental to mental health, recent studies are challenging this view by reporting robust health and well-being benefits linked to family caregiving. The current study attempted to provide an explanation of this apparent paradox by focusing on the role played by family health problems in the association between being a caregiver and mental health. Framed within the life course perspective and focusing on caregiving provided to aging mothers, the current study aimed 1) to demonstrate how the linkage between caregiving and depression reported in earlier studies may be misleading and 2) to further investigate whether caregiving to an aging mother may lead to any mental health benefits. Using longitudinal data drawn from the nationally representative US Health and Retirement Study, I follow adult children 50 and older who had a living mother during the observation period (N = 4812; 18,442 person-wave observations). A series of within-between random effects models were estimated to explicate how health conditions of aging mothers (i.e., disability and dementia) and caregiving transitions of adult children were associated with changes in depressive symptoms of adult children. Findings demonstrated that caregiving transitions were unrelated to depressive symptoms among adult children once the model controlled for the confounding effects of having their mother experience disability and dementia. Further, caregiving behavior was found to buffer the direct detrimental effect of maternal disability on adult children's depressive symptoms. This study adds to the growing body of research that cautions against characterizing caregiving as a chronic stressor detrimental to mental health and further echoes earlier calls for a more balanced portrayal of caregiving in policy reports and research literature.