Urinary incontinence in senile dementia of the Alzheimer type (SDAT).

Twenty patients (1 male and 19 females) with senile dementia of the Alzheimer type were studied using cystometry in combination with sphincter electromyography, brain computed tomography (CT) and evaluating the activities of daily life (ADL), with special reference to urinary incontinence. Seven of the patients were continent and the remainder were incontinent. Cystometry revealed uninhibited detrusor contraction in 8 out of the 13 incontinent patients, while no uninhibited contraction was found in 7 continent patients. There was a significant correlation between uninhibited detrusor contraction and urinary incontinence (p < 0.05). Brain CT showed that the degree of brain atrophy was more severe in those with uninhibited contraction than those without (p < 0.05). There was no clear relationship between sphincter coordination and the occurrence of incontinence. The ADL score tended to be lower in incontinent patients, although no significant difference was apparent (0.05 < p < 0.1). Uninhibited detrusor contraction and poor ADL functioning caused by brain atrophy are thought to be major causes of urinary incontinence in patients with senile dementia of Alzheimer type.