Oxford Handbook of Geriatric Medicine (2 edn)
Annotate
Cite
Urinary incontinence: causes
▸Incontinence has a major adverse impact on quality of life and has significant associated morbidity (it may be the last straw leading to institutionalization). Even longstanding cases may be reversible so always explore continence issues even if everyone else is complacent.
It is very common (around 30% of elderly at home, 50% in care homes) but is not a natural consequence of ageing. Most incontinence in older people is multifactorial, so think of all the possible contributing factors and address each in turn. They can be divided as follows:
Age-related changes
Diminished total bladder capacity but increased residual volume
Diminished bladder contractile function
Increased frequency of uninhibited bladder contractions
Reduced ability to postpone voiding
Excretion of fluid later in the day with less concentrated night-time urine
Atrophy of vagina and urethra in females
Loss of pelvic floor and urethral sphincter musculature
Hypertrophy of the prostate in males
Comorbidity
Diminished mobility—may have an urge to urinate then not be able to get to the toilet in time
Prescribed medications affect lower urinary tract, conscious state (eg sedatives) or ability to get promptly to the toilet (eg antihypertensives causing postural drop)
Increased constipation
Impaired cognition— a continent person needs to be able to recognize that they need to urinate, locate and reach a toilet, then undress in time to pass urine in the right place. Confusion can cause inappropriate micturition (initially failure to find an appropriate receptacle, then in later dementia they may be unaware altogether of urination). There may also be interference with UMN input into continence pathways
Reversible factors
UTI (see 
‘Urinary tract infection’, p.621)
Delirium
Drugs eg diuretics cause polyuria, anticholinergics such as tricyclics cause retention, sedatives can reduce awareness or mobility
Constipation—may cause voiding difficulty and increased residual volumes in both sexes
Polyuria (eg poorly controlled diabetes, hypercalcaemia, oedema resorption at night can cause nocturnal polyuria, psychogenic polydipsia)
Urethral irritability (eg atrophic vaginitis, candida infection)
Prolapse (women)
Bladder stones and tumours
Irreversible (but treatable) factors
In males, prostatic hypertrophy or carcinoma causes outflow obstruction, an unstable bladder or ‘overflow’ incontinence
Overactive bladder syndrome (symptom diagnosis)/detrusor overactivity (urodynamic diagnosis)—spontaneous contractions of the bladder muscle causes urgency and frequency ± incontinence
In females, outlet incompetence (stress incontinence)—usually due to pelvic muscle and ligament laxity (which supports the urethra) following childbirth—any rise in intra-abdominal pressure causes small leaks eg with cough, hoisting
Mixed symptoms—suggesting the presence of both overactivity and stress incontinence
Fistula (connection between the bladder and vagina) can occur after pelvic malignancy and irradiation, causing constant wetness
Environmental factors
Being bed bound and reliant on assistance with toileting makes continence a challenge. Whilst nurses will endeavour to promptly attend to a request for toileting, there is an inevitable delay
In males with reduced mobility, a lack of manual dexterity and/or small penile size can make the use of bottles a challenge
In hospitals, the toilet may be further away than at home, or difficult to find. In addition, the acute illness may mean that mobilizing is difficult
At home, access to a toilet may become harder with reducing mobility (eg if there is only an upstairs toilet)
Urinary incontinence: assessment
Much is made in the literature of the different symptoms in different diagnostic groups.
Urgency symptoms Frequent (>8 times per day) and/or precipitant voiding— strong urge, and decreased time to reach the toilet. If incontinence occurs this is termed wet overactive bladder (OAB). Urge alone whilst maintaining continence is dry OAB and may be a precursor to the wet form. Nocturnal incontinence common. Urge symptoms are commonly due to detrusor muscle overactivity where the residual volume small, but can also occur in obstruction
Stress symptoms Small volume leaks during coughing, laughing, lifting, walking and other exercise. Often coexist with urge symptoms in women
Obstructive symptoms in men include decreased force of urinary stream, hesitancy, and intermittent flow
Older patients are often unable to give precise descriptions and the different symptom complexes can overlap. Even where a ‘pure’ symptom complex exists you may get the diagnosis wrong, eg prostatic outflow symptoms where incontinence is actually detrusor overactivity or symptoms of urgency as a presentation for retention with overflow. Additional factors such as reduced mobility, dexterity, and cognition also interact to produce the syndrome of incontinence.
A more pragmatic approach is often required.
Take a history—a bladder or voiding diary can help, especially if you are relying on carers for information. Ask questions such as:
‘Do you know when you need to go to pass urine?’
‘Do you get much time between getting the urge and when the urine comes?’
‘Do you sometimes leak urine when you cough or run?’
Examination—include vaginal, rectal, and neurological examination
Exclude a significant residual volume See Box 20.1
Investigations—urinalysis and midstream urine (MSU), general screening blood tests, cytology and cystoscopy if haematuria. Urodynamics can be helpful if patient's incontinence cannot be explained or they are not responding to treatment and essential if surgical intervention is contemplated
Normal young people have only a few mL of urine post-micturition but normal elderly can have up to 100mL.
Causes of raised residual volume include:
Prostatic hypertrophy, carcinoma
Urethral stricture
Bladder diverticulum
Large urinary cystocele and other pelvic organ prolapsed (females)
Hypocontractile detrusor
Neurological disease eg Multiple sclerosis, Parkinson's disease, spinal cord disease, disc herniation
Bladder tumour
Drugs eg tricyclic antidepressants, anticholinergics
Acute retention is usually painful but can present atypically with delirium, renal failure etc.
Chronic bladder distention is usually painless, presenting with infection, abdominal distension/mass or incontinence (continuous dribbling due to overflow or urge incontinence due to detrusor instability).
Persistently elevated residual volume increases the risk of infection.
If pressure is elevated this can cause dilation of the urinary tract and eventually hydronephrosis and renal failure.
Residual volume can easily be estimated using a simple ultrasound bladder scan or a diagnostic (in/out) catheterization.
Bladder diaries
It is helpful to ask patients and/or carers to complete a bladder diary to aid assessment. This should include the timing and volume of all urine voided along with details of any symptoms and episodes of incontinence. An example is shown in Table 20.1.
| Date | Time | Voided volume | Symptoms | Incontinence episodes and cause |
|---|---|---|---|---|
| Date | Time | Voided volume | Symptoms | Incontinence episodes and cause |
|---|---|---|---|---|
Analysis of this will allow correct assessment of:
24-hr urine volume
Number and severity of incontinence episodes
Maximum and minimum voided volume
Diurnal variation
Urinary incontinence: management
Depends on cause so try to make a diagnosis first.
Incontinence is multifactorial in most elderly so combining treatments may be necessary eg a man with obstructive prostatic symptoms and detrusor hyperactivity may benefit from an α-blocker and an anti-muscarinic (eg tolterodine) (Table 20.2).
| Treatment | Indication | Notes |
|---|---|---|
Bladder retraining (gradually increasing time between voiding) | Overactive bladder syndrome/detrusor over activity | |
Regular toileting (taking to toilet every 2–4hr) | Dementia Overactive bladder syndrome | Decreases likelihood of incontinence episodes |
Pelvic floor exercises | Stress incontinence | Effect wears off when exercises stop |
Bladder stabilizing drugs Tolterodine 2mg bd–4mg od Solifenacin 5–10mg od Trospium chloride 20mg bd Oxybutynin 2.5mg bd–5mg tds | Overactive bladder syndrome/detrusor overactivity | May precipitate urinary retention—monitor carefully Side effects of dry mouth, constipation, postural hypotension may limit effectiveness. Titrate dose up slowly. Use for 6 weeks before maximal effect. |
Surgery —female | For stress incontinence—tension-free vaginal tape (TVT) is promising new procedure Colposuspension—gold standard operation | Refer for urodynamics to prior to surgery |
—male | For outflow tract obstruction TURP | |
Anti-androgens Finasteride 5mg od | For prostatic hyperplasia Improves flow and obstructive symptoms | Slow onset of action Decreased libido/impotence |
α-blockers Doxazosin 1mg–4mg od Tamsulosin 400micrograms od | Smooth muscle relaxant for BPH—improves flow and obstructive symptoms | Titrate dose slowly—watch for hypotension (especially postural) and syncope/falls Useful for co-treatment of hypertension |
Double micturition (ask patient to repeat voiding) | Sometimes helps reduce large residual volumes and decrease UTI | |
Intermittent catheterization | Atonic/hypotonic bladder—removing residual volumes daily can aid continence and reduce renal damage and infection. Also used to dilate stenotic urethras | Surprisingly well tolerated in ‘flexible’ elderly |
Synthetic vasopressin either oral or intranasal | Useful for nocturnal frequency | Main troublesome side effect is dilutional hyponatraemia—unlicensed for >65s in the UK Caution in patients with comorbid conditions, likely to be exacerbated |
| Treatment | Indication | Notes |
|---|---|---|
Bladder retraining (gradually increasing time between voiding) | Overactive bladder syndrome/detrusor over activity | |
Regular toileting (taking to toilet every 2–4hr) | Dementia Overactive bladder syndrome | Decreases likelihood of incontinence episodes |
Pelvic floor exercises | Stress incontinence | Effect wears off when exercises stop |
Bladder stabilizing drugs Tolterodine 2mg bd–4mg od Solifenacin 5–10mg od Trospium chloride 20mg bd Oxybutynin 2.5mg bd–5mg tds | Overactive bladder syndrome/detrusor overactivity | May precipitate urinary retention—monitor carefully Side effects of dry mouth, constipation, postural hypotension may limit effectiveness. Titrate dose up slowly. Use for 6 weeks before maximal effect. |
Surgery —female | For stress incontinence—tension-free vaginal tape (TVT) is promising new procedure Colposuspension—gold standard operation | Refer for urodynamics to prior to surgery |
—male | For outflow tract obstruction TURP | |
Anti-androgens Finasteride 5mg od | For prostatic hyperplasia Improves flow and obstructive symptoms | Slow onset of action Decreased libido/impotence |
α-blockers Doxazosin 1mg–4mg od Tamsulosin 400micrograms od | Smooth muscle relaxant for BPH—improves flow and obstructive symptoms | Titrate dose slowly—watch for hypotension (especially postural) and syncope/falls Useful for co-treatment of hypertension |
Double micturition (ask patient to repeat voiding) | Sometimes helps reduce large residual volumes and decrease UTI | |
Intermittent catheterization | Atonic/hypotonic bladder—removing residual volumes daily can aid continence and reduce renal damage and infection. Also used to dilate stenotic urethras | Surprisingly well tolerated in ‘flexible’ elderly |
Synthetic vasopressin either oral or intranasal | Useful for nocturnal frequency | Main troublesome side effect is dilutional hyponatraemia—unlicensed for >65s in the UK Caution in patients with comorbid conditions, likely to be exacerbated |
Catheters
A catheter is indicated for:
Symptomatic urinary retention
Obstructed outflow associated with deteriorating renal function or hydronephrosis
Acute renal failure for accurate urine output monitoring
Intensive care settings
Sacral pressure sores with incontinence
Where other methods of bladder management cause undue distress to a frail older person
Occasionally to facilitate discharge home by reducing care needs (especially overnight) where non-catheter options have failed
▸A catheter is NOT usually indicated for:
Immobility—even from stroke
Heart failure—just because you are giving furosemide
Monitoring fluid balance in a continent patient
Convenience of nursing—at home or in hospital
Asymptomatic chronic retention—refer to urology for assessment
Catheter selection
Long-term catheters should be either silicone, Silastic, or silver-impregnated (expensive but reportedly fewer blockages and infections)
Catheter size should be as small as practical
Catheters should be changed at least every 3 months
Consider the use of a catheter valve (like a beer keg tap) rather than a drainage bag
If duration is likely to be more than a year, consider suprapubic placement to preserve urethral sphincter function
In spite of correct diagnosis, investigation and treatment of reversible causes there will still be patients who will be permanently or intermittently incontinent of urine.
▸An indwelling catheter is not always the best solution. They have been shown to increase morbidity (infection, stones, urethral erosion) and even mortality.
Suggesting that catheters are removed is one of a geriatrician's most important jobs in post-acute care. If in doubt involve a specialist continence nurse/team.
Other options for continence management include:
Environmental modifications: urinals/commodes by the bed, easy access clothing, etc. can minimize or prevent accidents
Regular or individualized toileting programmes: this can be very successful in patients with dementia but is labour intensive
Pad and pants: can be very effective but is quite labour intensive for very immobile patients
A drainage sheath or condom catheter (Conveen® is a manufacturer) for men: like a catheter but held onto the penis with a plastic sheath like a condom. Particularly useful for isolated nocturnal incontinence as it can be removed by day. Main problem is displacement and leakage which can be a problem with small or unusually shaped penises
Intermittent catheterization: for those with obstruction or atonic bladders. Consider in agile, cognitively intact patients. Can be supported by district nursing services
Consider possibility of stones, infection, sediment, encrustation, constipation or bladder tumour
Renew catheter and change if necessary
Maintain good fluid intake
Catheter maintenance solution can be used for short periods
Blockage due to sediment can be prevented with regular saline bladder washouts
Catheter encrustation occurs with Proteus infection; acidic irrigations instilled into the bladder may dissolve these (eg Suby G®)
Catheters can irritate bladder causing contractions—resulting leak of urine past catheter can render them useless and occasionally causes very painful spasms
This is particularly common where detrusor overactivity was cause of incontinence
Can be induced or aggravated by infection
Exclude catheter blockage (presents with identical spasms and leaks)
If no residual volume, reduce catheter diameter/balloon size
Antimuscarinic drugs can sometimes help
Longer-term catheters can cause urethral sphincter incompetence, so urine will leak continuously. This may be temporarily helped by passing a larger gauge catheter but is a difficult problem to manage—avoid by using suprapubic catheters earlier
All catheters become colonized after a few days, all catheter urine will dipstick positive, and most catheter specimens of urine will grow bacteria
▸This alone is not an indication for antibiotics
Bad smelling, dark coloured, and cloudy urine is more commonly due to dehydration and is not an indication for antibiotics per se
There are now some trials of cranberry juice/capsules that suggest there is a minor effect on reducing recurrent infections
Only treat clinically significant infections (fever, malaise, delirium, pain, abnormal inflammatory markers, etc.) or you will just promote resistant organisms
If you believe a catheter is a source of significant infection:
Send a catheter specimen of urine to guide antibiotic choice
Remove the catheter where possible (even if only for 48hr). If not possible change catheter with a single shot of im gentamicin 80–120mg
Ensure adequate hydration
Choose a narrow spectrum antibiotic if sensitivities allow
For repeated significant infection consider if the catheter is really necessary. Low-dose continuous antibiotic prophylaxis are advocated by some but there is little evidence
Faecal incontinence: causes
Defined as the involuntary passage of faeces in inappropriate circumstances. The importance of situational factors mean there is potential for anyone to be incontinent in some circumstances.
Incontinence of faeces is always abnormal, and often curable
It is much less common than urinary incontinence, but more distressing
There is gross under-referral for diagnosis and treatment
Prevalence—10% of care home residents incontinent at least once per week
Continence mechanisms
The sigmo-rectal ‘sphincter’—the rectum is usually empty. Passage of faeces into the rectum initiates rectal contraction (and anal relaxation), normally temporarily inhibited. The acute angle in the pelvic loop of the sigmoid may be important in causing temporary holdup
The ano-rectal angle—the pubo-rectalis sling maintains an acute angle between rectum and anus, preventing passage of stool into the anal canal
The anal sphincters—the external sphincter (striated, voluntary muscle), the internal sphincter (smooth muscle), and the anal vascular cushions which complete the seal
Ano-rectal sensation—sensation in the anus and rectum is usually sufficiently accurate to distinguish gas from faeces, permitting the passage of flatus without incontinence. Good sensation may be particularly important when diarrhoea is present
Causes of faecal incontinence
Disorders of the anal sphincter and lower rectum: sphincter laxity (from many causes), severe haemorrhoids, rectal prolapse, tumours, constipation
Any cause of faecal urgency (occasionally associated with reduced mobility): constipation (with spurious diarrhoea), any cause of diarrhoea (inflammatory bowel disease, drugs, etc.)
Disorders of the neurological control of the ano-rectal muscle and sphincter: LMN lesions (neuropathic incontinence), spinal cord lesions, cognitive impairment (neurogenic incontinence)
The commonest cause (>50%) is faecal impaction. This is important because 95% are curable. The second commonest cause is neurogenic incontinence where the cure rate is still around 75%.
Faecal incontinence: assessment
Most patients can be helped by asking a few questions and performing a rectal examination.
Effective treatment is directed at the underlying cause so adequate assessment is vital.
History
The duration of symptoms is not helpful: impaction is just as common in those who have been incontinent for more than 3 months as in those in whom the incontinence is recent
Having the bowels open regularly (eg every day) is usual in elderly patients with impaction
Complete constipation (not having the bowels open at all) is unusual in impaction
A feeling of rectal fullness with constant seepage of semi-liquid faeces is almost diagnostic of impaction, but rectal carcinoma may also present in this way
The combination of urinary and faecal incontinence strongly suggests impaction as the cause of both
Soiling without the patient being aware of it suggests neuropathy
Examination
Inspect the anus—and ask the patient to strain as if at stool. Look for inflammation, deformities, large haemorrhoids (internal or external), and prolapse
Rectal examination—assess anal tone by the pressure on the finger after asking the patient ‘tighten’, feel for faeces and tumour, it is easy to miss even large internal haemorrhoids unless proctoscopy is performed
Abdominal examination—feel for the descending colon. Work proximally to assess colonic faecal loading (this may be misleading)
Neurological examination—look for signs of a peripheral neuropathy, and other neurological damage. Check perianal sensation (sacral dermatomes). Include a mental status assessment if you think neurogenic incontinence is likely
Investigation
A plain abdominal radiograph may be necessary to detect proximal faecal loading of the colon (see ‘Faecal incontinence: management’, p.544). Investigation of the anal sphincter tone and neurological control of rectum and anus is in the province of the proctologist and may occasionally be needed for neuropathic incontinence.
Faecal incontinence: management
The two common treatments in old age are for constipation and neurogenic incontinence. In addition specialist proctology clinics can perform ano-rectal physiology assessment prior to the use of biofeedback techniques and surgery (even colostomy).
Treatment of constipation
Faecal impaction, faecal retention, faecal loading.
▸In hospitalized older people, constipation is by far the commonest cause of incontinence; assume that any incontinent patient is constipated until proved otherwise and do not exclude it until after an adequate therapeutic trial of enemas for high faecal impaction.
Mechanism
Passage of faeces from the sigmoid into the rectum (often soon after a meal—the gastro-colic reflex) produces a sensation of rectal fullness, and a desire to defecate. If this is ignored, the sensation gradually habituates, and the rectum fills up with progressively harder faeces. At this stage, some leakage past the anal sphincter (incontinence) is almost inevitable. Impaction of hard faecal material produces partial obstruction, stasis, irritation of the mucosa with excessive mucus production, and spurious diarrhoea. Emptying the colon of faeces has two main effects: it prevents spurious diarrhoea and therefore urgency and it permits normal colonic motility and habit to be restored.
Treatment of neurogenic faecal incontinence
Loss of control of the intrinsic rectal contraction caused by passage of normal faecal material from the sigmoid into the rectum results in the involuntary passage of a normal, formed stool at infrequent intervals, and usually at a timing characteristic of that patient (typically after breakfast).
It is a syndrome analogous with the uninhibited neurogenic bladder, and usually only occurs in the context of severe dementia. However, note that incontinence in demented patients is commonly due to constipation. The diagnosis is therefore usually made in a severely demented patient with a characteristic history after excluding the other common causes.
Since the diagnosis is usually one of exclusion, it is reasonable to treat most patients as though they have impaction, particularly if you cannot exclude high impaction by radiology. Once impaction has been excluded, there are three strategies:
In patients with a regular habit, toileting at the appropriate time (perhaps with the aid of a suppository) may be successful. This requires an attendant who knows the patient well
Arrange for a planned evacuation to suit the carers, by administering a constipating agent (eg loperamide 2mg od) combined with a phosphate enema two or three times weekly
If the patient has no regular habit and refuses enemas, the situation may have to be accepted and suitable protective clothing provided
General—rehydration (possibly iv), regular meals, and help with toileting are important
Enemas—eg phosphate enema given once or (occasionally) twice daily. Continue until there is no result, the rectum is found to be empty on DRE and the colon is impalpable abdominally. This may take a week or more
Complete colonic washout—eg using bowel prep such as Picolax®. This is rather an extreme method but is sometimes required. Ensure the patient is well hydrated before you start
Manual evacuation of faeces—can cause further damage to the anal sphincters and is almost never necessary
Laxatives—generally less effective than enemas but can be used in addition, for milder cases and in the very frail. If the stool is hard use a stool softening laxative such as lactulose (20mL/day)—stimulant laxatives (eg senna) may produce severe pain. Stimulant laxatives or suppositories may be appropriate for those with soft faecal overloading. A combination of stool softener and stimulant are sometimes used. While extra fibre is useful in prophylaxis, stool bulking agents such as methylcellulose are of limited value in treating constipation as they increase the volume of stool being passed and may increase your problems
▸After treatment, think prevention (see b ‘Constipation’, p.370).
If, despite these measures, a patient has impaction for a second time (without an obvious and removable cause) then regular (say once or twice weekly) enemas should be prescribed. Progress can only be satisfactorily monitored by examining the patient abdominally and rectally.
