Comparisons between older men and women in the trajectory and burden of disability over the course of nearly 14 years.

OBJECTIVES: Across the life span, women live longer than men but experience higher rates of disability. To more completely evaluate these gender differences, the current study set out to compare the trajectories and burden of disability over an extended period between older men and women.
DESIGN: Prospective, longitudinal study with 13.5 years of follow-up.
SETTING: Greater New Haven, Connecticut. PARTICIPANTS: Participants were 754 persons, aged 70 years or older, who were initially community-living and nondisabled in their basic activities of daily living. MEASUREMENTS: Disability in 13 basic, instrumental, and mobility activities was assessed during monthly interviews, whereas demographic and clinical covariates were measured during comprehensive assessments every 18 months.
RESULTS: Five distinct trajectories were identified over successive 18-month intervals: independent, mild disability, mild to moderate disability, moderate disability, and severe disability. Women were more likely than men to experience the moderate and severe disability trajectories, but were less likely to transition from the independent trajectory to a worse disability trajectory during the subsequent 18-month interval. Women were also less likely to die after each of the five trajectories, and these differences were at least marginally significant for all but the independent trajectory. Over the entire duration of follow-up, women suffered from a greater burden of disability than men, but these differences were greatly attenuated after adjustment for the baseline levels of disability.
CONCLUSIONS: Gender differences in disability over an extended period can be explained, at least in part, by the higher mortality experienced by older men and the higher initial levels of disability among older women. These results suggest the need to take a life-course approach to better understand gender differences in disability.