Aging and the underactive detrusor: a failure of activity or activation?

To examine the known and potential contributions of motor, sensory, and biomechanical dysfunctions to the clinical problems of detrusor underactivity and detrusor hyperactivity/impaired contractility.

A review of the current literature on non-obstructive voiding dysfunction associated with aging was conducted. The functional impact of age-induced biomechanical tissue change via alterations in sensory transduction is considered.

Impaired contractility has been regarded as etiologic of detrusor underactivity. However, an age-related degradation in detrusor contractility as the primary contributor to impaired bladder emptying has not been conclusively demonstrated. To the extent that detrusor contraction force and duration are dependent upon efferent nerve activity and thus reflex responses to sensory activity, there is a potential impact of impaired sensory function on voiding efficiency. Structural and functional tissue changes accompanying aging may result in altered bladder afferent function, with subsequent reflex impairment of detrusor voiding function.

The relative contributions of motor, sensory, and biomechanical dysfunctions to impaired voiding performance independent of outlet obstruction associated with aging remain to be elucidated.