A 66-year-old woman complains of urinary urgency, frequency, and incontinence, and estimates that she voids 15 or more times within a typical 24-hour period. So far, she has lost only small amounts of urine—because she hurries to void at the first sense of urgency—but she is distressed and worried that she will have a major accident.
Sound familiar? Overactive bladder affects 17 to 33 million US women.1 Thanks to greater awareness and openness, more women today are seeking medical help for their troubling symptoms, although only a fraction have done so up to now.2 Ob/Gyns who are prepared to quickly evaluate the problem and initiate effective management can help restore the quality of life these patients enjoyed before onset of symptoms. This article:
- reviews the pathophysiology of “overactive bladder”
- describes a 4-step evaluation and management routine that should be feasible for any gynecology office setting;
- discusses the action and the efficacy of available and forthcoming drugs;
- uses newly revised terminology that reflects greater sensitivity to the patient.
4-STEP EVALUATION AND MANAGEMENT
- Ask the right questions, get voiding diary, assess quality of life.
- Perform ‘eyeball’ cystometry.
- Conduct a thorough physical assessment.
- Begin bladder retraining, pelvic floor muscle rehabilitation, and appropriate medical therapy.
Revised terminology
One of the most notable changes in the terms used to describe lower urinary tract dysfunction, proposed by the International Continence Society,3 is organization of the terminology into 3 categories: symptoms, signs, and urodynamic observations.
Symptoms are now defined to more closely reflect the way the patient perceives her problem, and are set forth without specifying the volume of urine required for a diagnosis of “abnormal” sensation or urgency.
Signs can be observed by the physician, such as leakage of urine when the patient coughs.
Urodynamic observations are made during urodynamic studies.
Overall, the new and revised terms are relatively vague to allow for patient-to-patient variability. Here are a few examples:
- Overactive bladder is a syndrome of symptoms that suggest dysfunction of the lower urinary tract. It is characterized by urgency with or without urge incontinence, usually involving frequency and nocturia.
- Urinary incontinence is any involuntary leakage of urine.
- Daytime frequency. The patient feels she voids more frequently than she should during the day.
- Nocturia. The patient wakes 1 or more times at night to void.
- Urgency. The patient feels a sudden, compelling desire to pass urine.
- Urge urinary incontinence is involuntary leakage accompanied by or immediately preceded by urgency.
- Bladder sensation is identified during history taking: normal, increased, reduced, absent, and nonspecific.
- Detrusor overactivity replaces the term “detrusor instability” or “hyperreflexia.” It is a urodynamic observation characterized by involuntary detrusor contractions during the filling phase, and may be spontaneous or provoked. It may be further qualified as neurogenic (if a neurologic condition underlies the problem) or as idiopathic.
What is abnormal bladder function?
Any actual incontinence should be considered abnormal, whether diurnal or nocturnal.
Frequency: More than 8 voids in 24 hours. Although an ordinary voiding pattern is not fully defined, most experts agree that a frequency of 8 or fewer voids in 24 hours is “normal.”
Urgency: Patient’s opinion determines. The sensation of urgency is more difficult to objectively define; hence, the need to rely on the patient’s perceptions. If a patient is voiding more frequently than normal because she has an uncomfortable, sudden desire to pass urine, she is considered to have urgency. In contrast, a woman who voids frequently because she has stress incontinence and wants to keep her bladder as empty as possible to avoid leakage has frequency without urgency. Urgency is best classified as being sensory or motor in nature.
- Sensory urgency is a strong, uncomfortable need to void without fear of impending leakage; for whatever reason, the bladder has become hypersensitive. Delaying voiding may result in pain but rarely leads to incontinence.
- Patients with motor urgency urinate frequently because they are afraid of experiencing a complete or partial involuntary void as a result of an involuntary bladder contraction.
How the normal bladder functions
The process of bladder storage and evacuation can be visualized as a complex of neurocircuits in the brain and spinal cord that coordinate the activity of smooth muscle in the bladder and urethra (FIGURE). These circuits act as “on/off” switches in the lower urinary tract, alternating between the 2 modes of operation: storage and elimination.
As the bladder gradually fills with urine, a woman initially perceives a first sensation of filling between 75 and 125 cc of urine, feels the first need to void at approximately 300 cc, and reaches maximum capacity and a strong urge to void at 400 to 700 cc.