Underactive bladder, detrusor underactivity, definition, symptoms, epidemiology, etiopathogenesis, and risk factors.

PURPOSE OF REVIEW: Lower urinary tract symptoms are bothersome and significantly impair patient's quality of life. Incomplete bladder emptying affects both men and women, and has shown to increase in incidence with aging. Incomplete bladder emptying is consequent upon an inability of the detrusor muscle to adequately contract to completely empty the bladder, with or without an increased bladder outlet resistance; this can be defined urodynamically as detrusor underactivity (DUA). The symptom complex consequent upon DUA is referred to as underactive bladder (UAB). Although the occurrence of DUA increases with age, and is commonly encountered in clinical practice, it is a largely unrecognized and consequently under researched condition.

RECENT FINDINGS: In this article, we will highlight the importance of DUA. We will review UAB as currently defined, the symptoms of DUA, its epidemiology, and etiopathogenesis, risk factors for developing DUA, and methods of diagnosis with an up-to-date review of the contemporary literature.

SUMMARY: DUA and its associated symptoms and signs are still poorly recognized entities. Difficulty and confusion arise in properly diagnosing DUA, as at present it can only be accurately defined on the basis of pressure flow urodynamics. Current attention is focused on validating a satisfactory definition for the syndrome complex of UAB.