Purpose: This research combined cross-sectional and longitudinal data to characterize age-related trajectories in physical disability for adults with and without diabetes in the United States and to investigate if those patterns differ by age, gender, race or ethnicity, and education.
Design and methods: Data were examined on 20,433 adults aged 51 and older from the 1998 to 2006 Health and Retirement Study. Multilevel models and a cohort-sequential design were applied to quantitatively depict the age norm of physical disability after age 50.
Results: Adults with diabetes not only experience greater levels of physical disability but also faster rates of deterioration over time. This pattern is net of attrition, time-invariant sociodemographic factors, and time-varying chronic disease conditions. Differences in physical disability between adults with and without diabetes were more pronounced in women, non-White, and those of lower education. The moderating effects of gender and education remained robust even after controlling for selected covariates in the model.
Implications: This study highlighted the consistently greater development of disability over time in adults with diabetes and particularly in those who are women, non-White, or adults of lower education. Future studies are recommended to examine the mechanisms underlying the differential effects of diabetes on physical disability by gender and education.