What can it be and what was it really? About bathing and urinary incontinence leading to nursing home admission.

To the Editor: We very much enjoyed reading the Editorial by Robert L. Kane ‘‘Ptolemaic Bathing’’ (1) and the original article by Gill and colleagues entitled ‘‘Bathing Disability and the Risk of Long-Term Admission to a Nursing Home’’(2). We would like to point out that, actually, Holroyd-Leduc and colleagues (3) did not find any independent relationship between urinary incontinence and Activities of Daily Living (ADL) decline; nor was incontinence related to nursing home admission overall after adjusting for confounders. Thus, the secondary analysis of the AHEAD (Assets and Health Dynamics Among the Oldest Old) cohort contradicted the prior findings of Thom and colleagues (4) based on medical records of a large health maintenance organization, bringing into question the previously established idea. Nevertheless, urinary incontinence was a significant predictor of nursing home admission in certain subgroups: in persons in the highest tertile for body mass index (BMI), in those with visual impairment, and in former smokers. This is explained by the author through an increased caregiver burden. The researchers only found a trend among those who were dependent in at least one ADL at baseline. But which ADL? It remains unclear, as usual, when defining ADL disability as ‘‘disability at least in one ADL’’ without taking into consideration the differential role of each ADL. Whether the interaction would become significant considering bathing disability independently is uncertain. Therefore, do the findings of Holroyd-Leduc and colleagues allow us to leave urinary incontinence out of the possible confounders of the relationship between bathing and nursing home admission? Apparently, Gill and colleagues (2) did not consider urinary incontinence as a possible confounder, although bathing disability, as a basic ADL, is known to be related to urinary incontinence (5). Kane proposes the appealing idea of searching for some other factors related to bathing that are also associated more causally with admission to a nursing home. Can urinary incontinence be one of those?