Physical disability reflects the cumulative burden of chronic conditions. Although generally progressive, episodes of disability can be followed by periods of recovery; therefore, there is a need to identify modifiable risk factors that contribute to the dynamic development of disability. This study investigated air pollution as a modifiable risk factor of transitions between states of no physical function limitation, physical function limitations, and activities of daily living disability.

The study included respondents older than 50 years. Physical disability states were assessed using self-reported mobility and activities of daily living. To examine associations of exposure to air pollution with transitioning between states of physical disability, multistate models, adjusted for individual- and area-level covariates, were used. Findings suggest that air pollution may affect the progression of physical disability and hinder recovery in later life.