Geriatrics - Continence

Question 1

In which group of patients is urinary incontinence most common?

Answer 1

Urinary incontinence is extremely common. It affects 1 in 30 people!

Women are more affected than men, with 2 out of 5 women over the age of 60 having continence problems. A general rule is that urinary incontinence in men is less than half that of women.

Question 2

How does the prevalence of urinary incontinence change with age?

Answer 2

Generally, urinary incontinence increases with age. Trends within prevalence data show that the median level of prevalence shows an:

• increase in young adult life
• a plateau in middle age
• a steady increase in later life

Question 3

How does the prevalence of urinary incontinence vary between acute hospital beds, HCE beds, RHs and NHs?

Answer 3

Urinary incontinence (+/- faecal incontinence) affects just under 1/3 of patients in acute hospital beds. This figure is roughly the same for residential homes. Nursing homes and HCE beds have higher and roughly equal prevalences of urinary incontinence.

The presence of faecal incontinence is roughly the same regardless of the location.

The presence of catheters is roughly the same on HCE as acute medical beds despite the prevalence of urinary incontinence being much higher in older patients. This is probably due to the fact that catheterisation is required in the acute setting to monitor urine output, and the fact that Geriatricians are keen to avoid catheters if possible.

Question 4

What is a useful approach to asking a patient about incontinence?

Answer 4

Many older people do not want to discuss the issue of incontinence or feel embarrassed by it. A sensitive approach is therefore very helpful.

This could simply be asking “Do you have any problems with your bladder or bowels?” or “Do you pass urine or faeces involuntarily?”

Question 5

What are lower urinary tract symptoms?

Answer 5

LUTS is the name given to symptoms associated with bladder and urethral problems that the International Continence Society has standardised.

Question 6

What is urgency?

Answer 6

This is a sudden, compelling desire to pass urine.

Question 7

Define hesitancy?

Answer 7

This is an involuntary delay or inability to initiate the urinary stream.

Question 8

Nocturia is…

Answer 8

…the need to pass urine during the night which awakens one from sleep.

Question 9

Urinary incontinence is

Answer 9

…the involuntary loss of urine.

Question 10

The bladder contracts spontaneously during filling as the patient attempts to prevent micturition. This is…

Answer 10

…detrusor overactivity.

Question 11

Nocturnal polyuria is…

Answer 11

…passing > 1/3 of your urine volume during the night.

Question 12

What is urge incontinence?

Answer 12

This is involuntary leakage of urine accompanied or preceded by urgency.

Question 13

Define overactive bladder?

Answer 13

This is a syndrome including urinary urgency +/- urge incontinence.

Question 14

Stress incontinence is…

Answer 14

…the involuntary leakage of urine caused by failure of the bladder outlet to remain closed when intra-abdominal pressure rises.

Question 15

What is the pathophysiology of incontinence?

Answer 15

Incontinence can result from:

1) weakness of the urinary outlet (stress incontinence)
2) failure of the bladder to store urine because of high bladder pressure (urge incontinence)
3) a combination of 1 and 2
4) a bladder that is overfull and overflows (bladder outlet obstruction)
5) abnormal communication of the urinary tract (fistula)
6) incontinence due to more general impairment (e.g. cognitive, functional, affective) (functional incontinence)

Question 16

Describe the phases of bladder filling and emptying?

Answer 16

Continence is maintained by the co-ordinated interaction of the bladder, urethra, pelvic floor muscles and the nervous system.

The bladder is a low pressure - high volume system: the bladder pressure increases slowly as the bladder fills.

Continence is maintained as long as the urethral pressure exceeds bladder pressure:

1) Storage phase:
- bladder fills and the urethra and pelvic floor contract
- first urge to void occurs at about 250ml, at this point the urethra and pelvic floor contract more

2) Emptying phase:
- when the bladder volume reaches the normal urge to void there is voluntary relaxation of the urethral smooth muscle that reduces urethral pressure
- pelvic floor relaxes
- bladder pressure increases as a result of detrusor contraction

3) Storage phase

Question 17

What is the detrusor muscle?

Answer 17

The detrusor muscle is a layer of the urinary bladder wall made of smooth muscle fibres arranged in spiral, longitudinal and circular bundles.

Stretching of the bladder wall signals the parasympathetic nervous system to contract the detrusor muscle.

Question 18

The trigone is….

Answer 18

…a smooth triangular area on the inner surface of the bladder. The triangle is formed by 2 ureteral orifices and the internal urethral orifice.

Question 19

Where is the external urethral sphincter located?

Answer 19

The external urethral sphincter is located at the bladders distal inferior end in females and inferior to the prostate in males.

It is made up of striated muscle and is therefore under voluntary control.

Question 20

What is the internal urethral sphincter?

Answer 20

The internal urethral sphincter is found at the junction between the bladder and the urethra. It is a continuation of the detrusor muscle and hence made of smooth muscle. It is only present in males.

Question 21

What is the periurethral striated muscle?

Answer 21

This is striated muscle that forms part of the pelvic diaphragm.

Question 22

What is the micturition cycle? What parts of the nervous system are involved?

Answer 22

The micturition cycle involves both somatic (voluntary) and autonomic nervous systems.

Voluntary control comes from the frontal cortex. The pontine micturition centre (midbrain) co-ordinates detrusor contraction with urethral relaxation.

Question 23

What controls bladder contraction?

Answer 23

Bladder contraction is mediated by the parasympathetic system. These parasympathetic fibres, along with those responsible for somatic control, originate from the sacral plexus (S2 to S4).

Excitation of the parasympathetic nerves in response to bladder filling stimulates acetylcholine release which acts at M3 muscarinic receptors causing detrusor muscle contraction.

Question 24

What mediates bladder relaxation/ filling?

Answer 24

Bladder filling is mediated by the sympathetic system. Sympathetic nerves arise from T11 to L2 and innervate the smooth muscle of the bladder neck and proximal urethra causing contraction allowing the bladder to fill.

Excitation of the pudendal nerve causes contraction of the external urethral sphincter, allowing voluntary control.

Question 25

Describe the micturition cycle from bladder filling?

Answer 25

During the storage phase, the bladder fills with only small increases in pressure. Sympathetic nerves from T11-L2 travel within the hypogastric nerves and synapse in the inferior mesenteric ganglion whence they innervate the bladder neck and proximal urethra causing contraction, allowing the bladder to fill.

Stretching the urinary bladder increases the frequency of action potentials travelling in sensory neurons to the spinal micturition centre (S2-S4) in the sacral region of the spinal cord. This increases parasympathetic outflow to the detrusor muscle and bladder neck via pelvic parasympathetic nerves (S2-S4) which causes contraction. This is INVOLUNTARY.

Sensory signals also ascend to the pontine micturition centre causing a conscious desire to urinate. If urination is convenient, then descending fibres activate sacral somatic motor neurons which cause relaxation of the external urethral sphincter, allowing micturition to take place.

Question 26

What type of incontinence do alpha blockers cause?

Answer 26

Alpha blockers such as doxazosin block adrenergic stimulation of the external urethral sphincter, bladder neck and proximal urethra, resulting in decreased tone and consequent stress incontinence.

Question 27

A patient presents with symptoms of urgency associated with occasional incontinence. Their bladder function is normal between times. What is the most likely diagnosis?

Answer 27

This is classic of overactive bladder. Remember this is a syndrome including urinary urgency +/- urge incontinence (which is the involuntary leakage of urine accompanied or preceded by urgency).

Question 28

A patient is started on amitriptylline for depression. They develop incontinence following this. What is the most likely cause of their incontinence?

Answer 28

Amitriptylline is a TCA and has anti-muscarinic side effects. Detrusor contraction is maintained by parasympathetic muscarinic fibres, which are inhibited by anti-muscarinic agents. As a result, patients tend to retain urine and develop overflow incontinence.

Question 29

What screening tools can be used to assess incontinence issues in older people?

Answer 29

All elderly patients should be asked about bladder and bowel problems. If they report a problem then a more objective assessment is required. The B-SAQ (Bladder Control Self Assessment Questionnaire) is a useful questionnaire that patients can fill out. It gives both a “symptom score” which confirms the presence of a urinary problem and a “bother score” which assesses how much their symptoms affect the patient.

Question 30

What a storage symptoms?

Answer 30

Nocturia
Continual urine loss
Frequency of micturition
Urgency
Urge incontinence
Stress incontinence

Question 31

Name some voiding symptoms?

Answer 31

Incomplete emptying
Hesitancy
Intermittent stream
Post micturition dribble 
Terminal dribbling

Question 32

What are some co-morbid conditions that can lead to incontinence?

Answer 32

Dementia
PD
Stroke
MS
CCF
Musculoskeletal disease

Question 33

What are some important consequences of incontinence?

Answer 33

Isolation
Depression
Falls
Skin infection
Admission to care homes
Reduced quality of life

Question 34

Examination in a patient with incontinence?

Answer 34

1) Cognition:
- AMT if concerns regarding cognitive impairment

2) Neurological:
- look for clues and assess gait
- check dorsiflexion of the toes (S3) and perineal sensation (L1-2) and sensation over the posterior aspect of the thigh (S3)

3) Abdomen:
- palpate for enlarged kidneys
- palpate abdomen for distended bladder
- DRE for anal tone

4) Pelvis:
- inspect for vaginal atrophy or prolapse
- assess pelvic floor muscle strength (e.g. Oxford classification)

5) Cardiorespiratory:
- signs of chronic lung disease or CCF

Question 35

What simple investigations should be performed on a patient presenting with incontinence?

Answer 35

Investigations for incontinence can be divided into simple and specialist. Simple investigations include:

1) Frequency/ volume charts:
- ask a patient to keep a diary over 3 days recording fluid intake, volume of urine passed and episodes of incontinence

2) Urinalysis:
- check for glucose (diabetes), protein (renal pathology), leucocytes and nitrates (infection), haematuria (stones or malignancy)
- MC&S

3) Bloods:
- FBC, leucocytosis may indicate infection
- U&Es, determine renal function
- Glucose, rule out diabetes
- Calcium, rule out hypercalcaemia which can cause constipation and confusion

4) Imaging

Question 36

What imaging modalities can be used to help investigate incontinence?

Answer 36

A post void bladder scan is an essential first line investigation and should be performed to rule out chronic retention of urine.

Other imaging modalities are not routinely indicated unless there are specific indications:

• USS abdo: requested if renal failure to evaluate kidney size and look for signs of obstructive uropathy
• CT urography: requested if considering renal stones
• CT abdo: to exclude abdominal or pelvic masses if these are suspected
• Intravenous urogram: useful if renal stones are suspected, but most centres use CT urography now

Question 37

What should be ruled out prior to referral for more complex investigations in incontinence?

Answer 37

It is essential to rule out UTI before referring for complex investigations.

Question 38

What trends are useful to look out for in frequency volume charts?

Answer 38

1) Frequent small volumes of urine - suggests OVERACTIVE BLADDER
2) >1/3 of total urine volume voided at night - suggests NOCTURNAL POLYURIA
3) >2500ml urine/day - indicates POLYURIA
4) Excessive intake of fluid or increased fluid intake in the evening - could lead to increased frequency

Question 39

What is uroflowmetry?

Answer 39

Of the specialist investigations that patients with incontinence can be referred for, this is perhaps one of the more simple ones. It basically measures urine flow rate.

It is a non invasive and useful technique for diagnosing bladder outlet obstruction. A commode, rotating disc flowmeter, computer and bladder scanner are required.

Question 40

In reference to uroflowmetry, define the following terms:

1) Flow time
2) Maximum flow rate
3) Time to maximum flow
4) Volume voided

Answer 40

1) Flow time = time during which measurable flow occurs, whereas the voiding time is the total duration of voiding including any interruptions
2) Maximum flow rate = maximum measured flow rate, Qmax, varies with age (decreases) and sex
3) Time to maximum flow
4) Volume voided = total volume voided through the urethra. A voided volume of >150ml is required for accurate interpretation

Normal results are indicated by a smooth parabolic curve on the uroflowmetry trace.

Question 41

What is a “fast bladder”?

Answer 41

This is a trace seen on uroflowmetry (remember this is a plot of flow rate vs time).

Fast bladder traces show an exaggerated flow rate and a decreased time to Qmax which can be found in patients with stress incontinence or problematic detrusor overactivity.

Question 42

What type of uroflowmetry trace is consistent with bladder outflow obstruction?

Answer 42

A prolonged flow trace is consistent with bladder outflow obstruction. There is a prolonged flow time and a low Qmax.

Question 43

What is an ultrasound cystodynamogram?

Answer 43

This test basically combines uroflometry with pre and post void bladder scans. These combined tests give information about functional bladder capacity, flow rate and post void bladder volume.

If after uroflometry +/- pre and post void bladder scans the diagnosis is still uncertain, more specialised tests should be considered - e.g. cystometry

Question 44

What is cystometry?

Answer 44

This refers to measurement of bladder pressure, sensation, capacity and compliance during filling and voiding.

The bladder is filled with saline at room temperature via a small bore urethral catheter which is passed along with a bladder transducer. A further pressure transducer is placed in the rectum. Pressure is recorded as the bladder is filled.

Question 45

In pressure urodynamics, how is true intravesical pressure calculated?

Answer 45

Intravesical pressure - rectal pressure

Transient rises in intra-abdominal pressure causes transient rises in intra-vesical pressure which can distort pressure urodynamic recordings. A way around this is to record rectal pressures using a rectal transducer as a proxy for intra-abdominal pressure and subtract it from the intra-vesical pressure.

Question 46

Name some transient, reversible causes of incontinence?

Answer 46

These can be remembered by the mnemonic “DIAPPERS”:

• Delirium: patients with acute confusional state often develop urinary incontinence
• Infection: urinary tract infection can cause bladder irritation
• Atrophy: vaginal atrophy is associated with urinary incontinence
• Pharmacological
• Psychological: several psychiatric diagnoses can lead to incontinence including depression and dementia
• Excess urine output: e.g. diabetes or excess fluid intake
• Restricted mobility
• Stool impaction: essential to rule out constipation as a cause of urinary incontinence, don’t forget a DRE

Question 47

Why are women more at risk of stress incontinence?

Answer 47

Women are more likely to develop stress incontinence for several reasons:

• bladder outlet is weaker due to short urethra and lack of prostate
• childbirth increases the risk of developing urinary incontinence
• obesity can contribute by