Cerebral aetiology of urinary urge incontinence in elderly people

We have examined 73 elderly incontinent patients (mean age 79 years) and 27 continent subjects (mean age 78 years) of similar cognitive status. Among the incontinent patients, 20 were shown objectively to have urge incontinence with normal bladder filling sensation, 14 had objectively demonstrated urge incontinence with reduced bladder sensation, and 39 had other types of incontinence. We compared cognitive function (by Mini-mental State Examination: MMSE) and regional brain perfusion (by SPECT scanning) in these four groups. Patients with objectively demonstrated urge incontinence and reduced bladder sensation stood out as being different from the rest: their mean MMSE score was significantly lower than that of any of the other three groups; perfusion of the frontal cortex was significantly poorer than that in the continent and other incontinent groups; global cortical perfusion was significantly poorer than in the other incontinence groups. This was not found in patients with urge incontinence and normal bladder sensation. The observations support the hypothesis that in elderly people urge incontinence with reduced bladder sensation can be a consequence of cortical neuropathy, especially in the frontal lobes.