Commentary

The study by Brown et al is part of the larger SOF, a US cohort study of community dwelling elderly women. In this report, data collected at the time of the fifth follow up visit were examined to determine whether urinary urge and stress incontinence were independent risk factors for falls and fractures. The results show a small but statistically significant increase in risk for falls and fractures from urge but not stress incontinence. From a methodological standpoint, the study is strong: it included a defined, representative sample of patients; follow up was sufficiently long; and outcome criteria (fractures) were objective. Multivariate analyses were done, adjusting for several known prognostic factors, including age, use of sedative medication, frailty, relevant medical problems, and gait and balance abnormalities.¹ Missing from the multivariate analysis was adjustment for cognitive impairment, and because urge incontinence is often present in patients with subcortical dementia, this omission may be relevant. It is also possible that medication used to treat incontinence (eg, anticholinergic agents) contributed to the falls. The fact that a dose response curve existed with patients who noted more frequent (ie, daily) urge incontinence having a higher risk for falls (35%) than patients with weekly incontinence (21%) supports an aetiological association.

It is premature to speculate about the clinical significance of the findings of this study, other than as another, perhaps unexpected, risk factor for falls. Tinetti et al showed that falls have many causes and that treating some of these contributing factors decreases the risk for falling.^{1, 2} If incontinence is validated as a risk factor for falls and fractures in an independent group (test set) of patients, then treatment of urge incontinence could be evaluated for the possible added benefit of preventing falls.