This study has several strengths. It was conducted prospectively over three years, had a low
drop out rate, had a large number of functionally-intact older adults, included a large
proportion of older African Americans, and provided detailed data on medication use
including route of administration. It also has a number of potential limitations. The
incontinence measure we used was subjective self report rather than an objective
determination by a physician. However, self-report of incontinence correlates well with
objective determination and is consistent with the approach used by other epidemiological
studies. 7,11 Moreover, self report of urge incontinence, the most common type of
incontinence reported by older women in other studies, has been found to have positive
predictive values between 70 to 85% with urodynamically assessed urge urinary
incontinence.27 A second limitation is that we may have lacked power to examine the
multivariable impact of the use of various medications/classes (i.e., anticholinergics, alpha
blocker and estrogen use, CNS drugs, and various diuretics). Also due to small numbers we
were not able to conduct analyses stratified by race and type of urinary incontinence. A third
limitation is as always, unmeasured factors (e.g., other behavioral or surgical treatment of
urinary incontinence) may have confounded the findings. We did however control for
numerous potential confounders, including common indications for medications. Finally,
this is a study of well functioning community dwelling older women at baseline living in
two US states and may not be representative of older women elsewhere.