Urinary Incontinence

percent of women with UI over 65 years will be

these theories. In summary, there is damage to

hospitalized within 1 year. Older men with UI

afferent or efferent pathways, leading to

are twice as likely to be hospitalized over a

decreased capacity for increased afferent infor-

12-month period. There is a strong association

mation, decreased suprapontine inhibition, and

between UI, acute hospitalization, institutional-

increased sensitivity to contraction-mediated

ization, and death. UI is most alarmingly associ-

transmitters.33,34

ated with increased mortality.12,26

The micturition reflexes involve several neu-

Daily costs associated with UI are not insig-

rotransmitters and transmitter systems which

nificant. Protective garments and bedding are

may be targets for drugs aimed at micturition

expensive and often not covered by private

control. Glutamate likely acts as an excitatory

insurance or Medicare. The productivity of the

transmitter in the supraspinal control circuitry

individual and relative caregiver may be com-

and in the efferent limb of the pontine micturi-

promised in coping with the unpredictability of

tion center and the preganglionic neuron. Other

UI. UI is the most common cause of institution-

substances, such as GABA, serotonin, dopamine,

alization of elderly with relatives unable to meet

and norepinephrine, can exert modulatory

their needs. In long-term care facilities, there is

effects on the glutamatergic mechanisms con-

an additional $5,000 burden to total health care

trolling micturition, and the receptors for these

cost per resident with UI. In 2000, the estimated

substances may be potential sites for drug inter-

direct cost of UI in the United States was $19.5

vention. GABA may act as an inhibitory neu-

billion.12,22,27

rotransmitter in the brain and depress excitatory

(diencephalon) or inhibitory (mesencephalon

Pathophysiology

and telencephalon) mechanisms for micturition

control. The serotonergic input from the raphe

nucleus and multiple serotonin 5-HT receptors

Classically, the pathophysiology of UI is

at afferent and efferent impulse processing sites

described as either an overactive detrusor (OAB)

causes inhibition of bladder contractions. Thus,

or an incompetent urethral sphincter. The

drugs interfering with serotonin reuptake (i.e.,

underlying pathophysiology of OAB can relate

serotonin reuptake inhibitors) may have the

to alterations in any of the reflex cycles in nor-

opposite effect. Central dopaminergic and nora-

mal micturition or morphological changes in

drenergic pathways may have excitatory and

the smooth muscle, nerves, or urothelium. The

inhibitory effects on bladder function, yet drugs

three main theories for the cause of OAB are: the

selectively acting at the dopaminergic and

myogenic or muscle-related theory, neurogenic

adrenoreceptors have not been established.35

or nerve-related theory, and the autonomous

SUI results from bladder neck/urethral

bladder theory. In the myogenic theory, partial

hypermobility and/or neuromuscular defects,

denervation of the detrusor, regardless of etiol-

i.e., intrinsic sphincter deficiency. This occurs

ogy, can alter the smooth muscle leading to

when the intra-abdominal pressure exceeds

increased excitability and electrical coupling

urethral resistance. Among women, these

between cells.28-30 The neurogenic theory sug-

changes occur due to weak collagen, advanced

gests that damage to central inhibitory pathways

age, pregnancy, obesity, advanced pelvic pro-

in the brain or spinal cord or sensitization of

lapse,and chronic obstructive airway disease.4,36

peripheral afferent terminals in the bladder can

In men, SUI is due to an iatrogenic cause. A rad-

unmask primitive voiding reflexes that trigger

ical prostatectomy can injure the sphincteric

detrusor overactivity (DO).31 The newest of the

mechanism (rhabdosphincter) or cause bladder

three theories, autonomous bladder theory,

dysfunction. Suggested mechanisms for sphinc-

notes that the detrusor is modular (i.e., circum-

teric injury following a radical prostatectomy

scribed areas of muscle). During normal filling,

include: ischemia and immobilization by scar,

the autonomous activity with nonmicturition

atrophy, direct pudendal nerve injury, or short-

contractions and phasic sensory discharge can

ening of urethra below a critical functional

become modified. This may lead to excessive

length.37

excitatory inputs or failure of inhibiting inputs.32

Controversy surrounds urethral length as a

Either way, the etiology is variable in different

cause of incontinence. Technical modifications

individuals and may include one or more of

have been made to preserve as much external

440

PRaCtiCal URology: ESSEntial PRinCiPlES and PRaCtiCE

sphincter as possible following a radical pros-

assessment should include a urinalysis (urine

tatectomy.38 During a TURP, the verumontanum

culture as needed) to exclude infection, hematu-

marks the proximal part of the rhabdosphincter.

ria or glucosuria, measurement of postvoid

Resection distal to the verumontanum can lead

residual to identify possible bladder dysfunction

to sphincteric incompetence. Sphincteric dener-

or obstruction, and a quality of life (QoL) ques-

vation can also occur following other radical

tionnaire34 for assessment of patient-reported

pelvic procedures, i.e., abdominoperineal resec-

outcomes (PRO).

tion, pelvic radiation.

PROs are the best measure of patient health

Among postprostatectomy incontinence (PPI)

status as directly reported by the patient. They

patients, 60% experience detrusor overactivity.

assess outcomes of health-related quality of life

The bladder dysfunction leading to UUI must

(HRQL), symptoms, patient satisfaction, and

be addressed prior to discussing surgical treat-

social, emotional, and physical functioning. The

ment of SUI.39 Groutz et al. used urodynamic

value of these outcomes relies on the validity

and clinical evidence to report on 83 men with

and reliability of the survey tools being used.

PPI. Intrinsic sphincter dysfunction was the

PROs require linguistic validation and psycho-

most common videourodynamic finding and

metric evaluation of multiple language versions

cause of incontinence in 73 (88%) men. Bladder

of a questionnaire. Psychometric characteristics

overactivity was the main cause of incontinence

include: internal consistency, reliability, con-

among 6 (7.2%) men. Overflow incontinence

struct validity, and responsiveness. There are

secondary to a bladder neck contracture was a

multiple

International Continence Society

significant cause of intrinsic sphincter defi-

(ICS)–validated assessments which are actively

ciency in 25 (30.1%) patients.40

utilized for incontinence in men and women,

such as the ICS Male Questionnaire, Urogenital

Clinical Assessment

Distress

Index

(UDI-6), or

International

Consultation on

Incontinence

Questionnaire

of Incontinent Patient

(ICIQ). For example, the overactive bladder

questionnaire (OAB-q) is a 33-item, self-admin-

istered, disease-specific questionnaire to assess

Incontinence can cause tremendous suffering.

symptom bother and HRQL in patients with

Hence, it should be assessed thoroughly and

OAB. This questionnaire was recently validated

treated appropriately. A full and thorough his-

and shown to have acceptable psychometric

tory and physical exam is an important first step

characteristics in multiple languages (Danish,

in directing appropriate investigations.Providers

German, Polish, Sweden, and Turkish).41

should examine fluid intake, assess volume of

Patient-completed voiding diaries are an inte-

urine lost, number and type of pads used,

gral measurement tool for those presenting with

strength of urinary stream, stress maneuvers or

complaints of incontinence associated with

changes in posture associated with urine loss,

urgency. Patients are given standard instruc-

and if urgency is associated with leakage. Add-

tions to record micturition events (± voided vol-

itional information should be collected regard-

umes) and incontinence episodes, while also

ing risk factors and predisposing factors.

recording whether the void or leakage episode is

Medication history,including diuretics or hyper-

associated with a sense of urgency. Brown et al.

osmolar infusions, anticholinergics, narcotics,

examined the test-retest reliability and validity

sedatives, and hypnotics, is important to docu-

of 7-day voiding diaries in the assessment of

ment. These may be associated with functional

OAB symptoms. The diary demonstrated excel-

incontinence, especially among the elderly.12

lent reliability with respect to the symptoms of

Physical examination should include a complete

“strong urge,” diurnal and nocturnal micturi-

neurologic, abdominal, urogenital, pelvic, and

tions, total incontinence, and urgency inconti-

rectal examination. Female pelvic exam should

nence episodes.42 Short voiding diaries have

make note of urethral pathology, urethral hyper-

been shown to be just as reliable and valid as

mobility, prolapse, and apical support. Anal bul-

traditional 7-day diaries and are less burden-

bocavernosus reflexes should be assessed.

some to patients.43,44

Urethral sphincteric response to cough or

Urodynamic studies are not mandatory, but

Valsalva should be documented. The basic

are crucial when

a diagnosis

is unclear, in