Predisposing Factors and Precipitants for Bathing Disability in Older Persons

OBJECTIVES: To identify potential predisposing factors and precipitants for bathing disability. DESIGN: Prospective cohort study. SETTING: Greater New Haven, Connecticut. PARTICIPANTS: Seven hundred fifty-four community-living residents aged 70 and older. MEASUREMENTS: Potential predisposing factors were measured every 18 months for 6 years during comprehensive home-based assessments. Participants were followed with monthly telephone interviews for a median of 61 months to ascertain exposure to potential precipitants, which included illnesses and injuries leading to hospitalization or restricted activity, and to determine the occurrence of persistent disability in bathing. RESULTS: Over the course of nearly 8 years, 333 (44.2%) participants developed persistent disability in bathing. After accounting for age, sex, and race, nine predisposing factors were independently associated with persistent bathing disability. The strongest associations were found for inability to rise from a chair, low bathing self-efficacy, and low physical activity, each of which more than doubled the risk of persistent bathing disability. After the potential precipitants were added to the final model, the associations between the predisposing factors and persistent bathing disability were only modestly diminished. The effects of the precipitants on persistent bathing disability were large, with multivariable hazard ratios of 24.6 for hospitalization and 3.01 for restricted activity only. The relative contributions of the predisposing factors and precipitants to the development of persistent bathing disability were 47.7% and 27.1%, respectively. CONCLUSION: Disability in bathing is attributable to a combination of predisposing factors that make community-living older persons vulnerable and intervening illnesses or injuries that act as precipitants. These factors and precipitants may be suitable targets for the prevention of bathing disability.