The Impact of Dynamic Income Disparities on Disability Progression in Older Adults: A Joint Group-Based Trajectory Modeling Study.

Understanding the relationship between income disparities and disability progression is crucial for developing effective aging strategies. Using data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), this study aims to assess the dynamic interplay between income and disability among the older adults in China. We used joint group-based trajectory modeling to identify distinct income and disability trajectories, and multinomial logistic regression was employed to explore the association between these trajectories. Our findings showed that participants aged 60-69 with low but stable income trajectories exhibited a higher likelihood of rapid disability recovery. In contrast, more than 30% of the participants aged 70-79 and 80+ experienced rapid disability deterioration, while higher income trajectories in these older cohorts were associated with accelerated disability. The findings highlight the importance of targeted financial support and preventive healthcare interventions for older adults, particularly those aged 60-69 with low but stable incomes.