Examining racial and ethnic differences in disability among older adults: A polysocial score approach

Abstract

ObjectivesRacial and ethnic disparities in disability in activities of daily living (ADL) continue to be a public concern. We evaluated whether the polysocial score approach could provide a more comprehensive method for modifying racial and ethnic differences in such disability. Study designCohort study. Main outcome measuresWe included 5833 participants from the Health and Retirement Study, who were aged 65 years or more and were initially free of ADL disability. We considered six ADLs: bathing, eating, using the toilet, dressing, walking across a room, and getting in/out of bed. We included 20 social factors spanning economic stability, neighborhood and physical environment, education, community and social context, and health system. We used forward stepwise logistic regression to derive a polysocial score for ADL disability. We created a polysocial score using 12 social factors and categorized the score as low (0–19), intermediate (20–30), and high (31+). We used multivariable logistic regression to estimate the incident risk of ADL disability and examine additive interactions between race/ethnicity and polysocial score. ResultsA higher polysocial score is associated with a lower incidence of ADL disability among older adults in the United States. We found additive interactions between race/ethnicity and polysocial score categories. In the low polysocial score category, White and Black/Hispanic participants had a 18.5 % and 24.4 % risk of ADL disability, respectively. Among White participants, the risk of ADL disability decreased to 14.1 % and 12.1 % in the intermediate and high polysocial score categories, respectively; among Black/Hispanic participants, those in the intermediate and high categories had a 11.9 % and 8.7 % risk of ADL disability, respectively. ConclusionsThe polysocial score approach provides a new opportunity for explaining racial/ethnic disparities in functional capacity among older adults.