Section 1: Epidemiology and aetiology
Urinary incontinence (UI) is a symptom-based condition described as the 'complaint of involuntary loss of urine' as set out by the International Continence Society and the International Urogynecological Association. This article focuses on UI in women.
The number of patients experiencing UI is likely to be under-reported and varies with sex, age group, parity and medication (see box).
UI is more common in women, with a prevalence of 17-40% in the UK.1,2 UI is more common in the elderly population and can have a significant impact on the psychological and social wellbeing of the person.3 Its aetiology is usually multifactorial and can include transient causes (see box).
- Stress UI: involuntary loss of urine occurs on effort or physical exertion, related to an increase in intra-abdominal pressure. It can be associated with bladder-neck weakness, obesity, poor pelvic floor muscle strength or nerve damage
- Urgency UI or overactive bladder (OAB): involuntary loss of urine occurs in association with urgency. This is typically caused by overactivity of the detrusor muscle and may be secondary to lesions affecting the motor or sensory pathways to the muscle. Causes include MS, neurological injury, diabetes, stroke, Alzheimer's disease, Parkinson'sdisease and idiopathic causes
- Mixed UI: a combination of stress UI and urgency UI.
- Overflow incontinence: this can occur with bladder detrusor atony or bladder outlet obstruction secondary to a prolapsed uterus, previous surgery or incontinence procedure.
- Functional incontinence: this occurs when the patient has difficulty reaching the toilet in time, such as with restricted mobility or altered mental capacity.
- Nocturnal enuresis: involuntary loss of urine occurs during sleep and is more common in children. It can be due to a delay in development of bladder control, but can also be due to inadequate toilet training, urinary infections or emotional distress. There is a strong genetic association.
- Continuous UI: an involuntary continuous loss of urine. This can be due to a fistula or distorted anatomy.
Several newer classifications have also been devised:
- Postural UI: an involuntary loss of urine that occurs in association with a change in body position.
- Insensible UI: the patient is unaware of the occurrence and origin of the loss of urine.
- Coital incontinence: an involuntary loss of urine with coitus that can occur during penetration or with orgasm.
Important! UI is more common in women, with a prevalence of 17-40% in the UK.
Section 2: Making the diagnosis
On average, a woman will have experienced UI for six to nine years before seeking medical help.5 Diagnosis of UI is based on history, basic investigations and examination. Guidelines issued by NICE highlight the importance of a good history, including bladder diaries and routine digital pelvic floor assessment, as well as being guided by the patient's symptoms and the effect on their quality of life.6
The emphasis is on treating the predominant symptom and the vast majority of patients will fall into three categories; stress incontinence, urgency incontinence or mixed incontinence.
The points to elicit are the main urinary symptoms affecting the patient. This will include UI associated with an increase in abdominal pressure (coughing, sneezing, physical activity), or incontinence with urgency, frequency and nocturia.
The duration of symptoms and the impact on the patient's quality of life and wellbeing should also be recorded. Enquiries should also be made regarding intake of caffeinated drinks, red wine and acidic or spicy food.
If an acute onset of UI has occurred, a review of any new medications and a full neurological examination should be performed. Restricted mobility, cognitive impairment and depression should also be excluded as causes for UI.
If symptoms of pain, poor urinary stream or hesitancy are present, a referral for specialist urogynaecology review should be considered.
According to the NICE guideline,6 in women with UI or OAB, a urine dipstick assessment should be performed to exclude a UTI and a specimen sent for microscopy and culture (MSSU) if abnormal.
The guidance suggests, in patients symptomatic of a UTI with a positive dipstick for leucocytes and/or nitrites, antibiotics may be commenced while waiting for the MSSU result. If the dipstick is negative, consideration may be given for antibiotics while awaiting the MSSU results.
In those asymptomatic of a UTI with a positive dipstick, the MSSU result should be awaited before starting antibiotics.6
If possible, it is optimal to examine the patient with a comfortably full bladder. This may aid confirmation of leakage of urine with a cough test during examination. It is important to exclude any large pelvic or abdominal masses on abdominal examination.
Speculum and bimanual examination will be used to assess for atrophic vaginitis, prolapse and pelvic floor muscle contraction using the Oxford scale (1-5/5). Should a pelvic mass be found, a two-week referral should be organised. Ultrasound will be needed but should not delay the referral.
A bladder diary should be completed for duration of at least three days, including a normal working day and a normal resting day. This will allow a good assessment of functional bladder capacity.
Important! In women with UI/OAB perform a urine dipstick assessment to exclude UTI.
When to refer
Urgent referral should be considered (possibly via a fast-track pathway) in the following situations:
- Microscopic haematuria in the absence of a UTI
- Macroscopic haematuria
- Pelvic pain
- Pelvic or vaginal mass
- Complex neurological symptoms
- Women >40 years old with haematuria and recurrent UTIs
Routine referral should be considered in the following cases:
- History of previous pelvic surgery or radiation therapy
- Suspected urogenital fistulae
- Severe prolapse (grade 3 utero-vaginal prolapse)
- Patients refractory to conservative treatment
- Sensory symptoms consistent with a change in normal sensation or function during bladder filling
- Voiding and post-micturition symptoms such as hesitancy, slow stream, intermittency, straining to void, spraying of urinary stream, feeling of incomplete bladder emptying, double voiding, post-micturition leakage, urinary retention and position-dependent micturition
Section 3: Managing the condition
Management should involve the GP, community continence adviser, specialist physiotherapist and/or specialist nurse.
Fluid intake should be approximately 1.5-2 litres per day.6 Weight reduction is advisable for patients who have a BMI greater than 30.
Educational leaflets on pelvic floor muscle training (PFMT) should be provided and supervised programmes should comprise at least eight contractions performed three times per day. Supervised PFMT should be undertaken for at least three months for women with stress or mixed UI.
Caffeinated beverages should be restricted or stopped as caffeine is an irritant to the detrusor muscle, as well as a diuretic. In urgency or mixed UI, bladder retraining for a minimum of six weeks and avoidance of drink four hours before sleep will help towards managing OAB symptoms.6
Management of other exacerbating conditions such as constipation and smoking cessation (aiming to reduce cough) will also help. In certain cases and in those with cognitive impairment, timed voiding can be employed to reduce the number of episodes of UI.6
Important! Fluid intake should be 1.5-2 litres per day.
In cases with stress UI symptoms, where women can not contract their pelvic floor or standard PFMT has not given a satisfactory result, options to maximise pelvic floor contractility are:
- Biofeedback PFMT: a device is used to convert the pelvic floor contraction into an auditory or visual response, thereby allowing objective observation of improvement
- Electrical stimulation
- Weighted vaginal cones
These therapies are generally undertaken with the supervision of the community continence adviser, specialist nurse or physiotherapist.
When conservative measures for OAB are unsuccessful, the next step is pharmacological treatment. Any co-existing medical conditions should be reviewed, along with the concurrent use of other medications that could potentially affect the total antimuscarinic load, and the risk of adverse effects considered.
Antimuscarinics are commonly used, with similar side-effects reported and variable tolerability between patients. Before commencing medication, the likelihood of success and associated side-effects should be discussed. The patient should also be made aware that some side-effects may indicate the treatment is starting to take effect, and that they may not see the full benefit until four weeks of medication.
Two different antimuscarinics should be tried before referral to secondary care.
According to the NICE guideline, first-line drugs are oxybutynin (immediate-release), tolterodine (immediate-release) or darifenacin, and should be commenced at the lowest recommended dose.6 Oxybutynin immediate-release should not be offered to frail older women.
Four weeks after commencing a new drug, a telephone or face-to-face review should be offered to assess patient satisfaction, effectiveness and tolerability, the need for a dosage increase if suboptimal effect, or the need for a change to a second antimuscarinic if intolerable side-effects or no effect.
The patient should be reviewed again after a further four weeks. Selection of a second antimuscarinic should be based on the lowest acquisition cost and transdermal medication should be offered if women are unable to tolerate oral medication.
Mirabegron, a beta-3 agonist, has a different safety profile and potential side-effects. It can be used when antimuscarinics are either contraindicated, have failed to achieve satisfactory symptom relief or intolerable side-effects are reported. It is contraindicated in patients with severe hypertension and blood pressure should be monitored before and during treatment.
Yearly review should be undertaken in patients on continued long term pharmacological treatment or six monthly in patients over 75. See box below for a summary of common pharmacological treatments used.
With mixed UI, management should aim to treat the predominant symptoms. In cases where stress UI is the predominant symptom, benefits of conservative management including the use of OAB drugs should be discussed prior to offering surgery.
Patients should be referred if conservative measures have failed. Urodynamic studies (UDS) may aid management but should not be undertaken prior to commencing conservative measures. UDS may not be required in patients who have pure stress UI based on history and examination, but the vast majority will have UDS performed prior to surgery. UDS should be undertaken in patients with OAB, symptoms suggestive of voiding dysfunction or patients who have had previous surgery for stress UI.
For cases of stress UI where conservative measures have failed, patients should be offered synthetic mid-urethral slings (MUS), autologous rectus fascial slings or open colposuspension, and the risks and benefits of each option should be discussed.The majority of procedures currently performed are synthetic MUS due to the lower complication rates in comparison to colposuspension.
Intramural bulking agents can also be considered but patients should be made aware that the effectiveness is greatly reduced compared to synthetic or autologous rectus fascial MUS, repeated injections may be required and efficacy diminishes with time.
In cases where the patient is unfit to undergo surgery or would prefer a non-surgical treatment for stress UI, an alternative is duloxetine. This has a high risk of adverse effects and is therefore not generally tolerated or prescribed.
For OAB, referral to secondary care should be offered when the response to two anticholinergics or mirabegron has not been satisfactory, or the patient wishes to discuss further options.
UDS should be performed to confirm detrusor overactivity is present and responsible for her OAB symptoms. Invasive treatment with intravesical injection of botulinum toxin A should then be offered.
Patients should be advised regards the likelihood of symptom reduction or resolution, the risk of adverse effects (e.g. potential need for clean self-catheterisation and increased risk of urinary tract infections), the paucity of evidence on long-term risks and the likelihood that repeated injections will be required.
Patients should be willing, trained and able to self-catheterise in order to have the procedure. They should also be made aware that this treatment does not currently have regulatory approval for idiopathic OAB.
An alternative for patients unresponsive to medical treatment, unwilling to try botulinum toxin A, or unable to self-catheterise is percutaneous sacral nerve stimulation.
This requires a multidisciplinary team review (MDT) and discussion with the patient regarding the long-term implications, including probability of success (55-65% symptom improvement and improvements in bladder capacity), risk of failure and adverse effects, potential need for surgical revision and the long-term commitment required.Availability of this treatment is limited as there are few centres in the UK that offer it.
Transcutaneous sacral nerve stimulation and posterior tibial nerve stimulation are not currently offered due to limited evidence. Percutaneous posterior tibial nerve stimulation should not be offered unless there has been a MDT review, conservative measures have not been successful, and the patient does not want botulinum toxin A or percutaneous sacral nerve stimulation.
Uncommon procedures for severe OAB refractory to medication and neuromodulation are augmentation cystoplasty or ureteric diversion and defunctioning of the bladder.
Important! Patients should be referred if conservative measures have failed.
Section 4: Prognosis
Prognosis depends on cause, patient expectations and desired outcome. Multiple outcomes are used to classify success – subjective, such as patient perception of improvement; or objective, such as urodynamic confirmation of resolution.
PFMT alone can improve symptoms of stress incontinence by 56-75%, but appears to be less effective in the long term and is dependent on compliance.7
Transurethral bulking agents can provide short-term improvement of 70-81%.8 They can be inserted under local anaesthetic, have few complications and are a suitable alternative for patients medically unfit for more complex surgery.
Burch colposuspension is known to have 53-94% continence rate during the first year and 70-86% in the long-term,9 and is still considered first line for surgical treatment of stress incontinence. However, MUS has a comparable improvement in symptoms of 85-96% and has overtaken colposuspension due to lower morbidity and shorter hospital stays.10
Single-incision mini-slings have come into use, but short term efficacy is reduced compared to standard MUS and long term data is awaited.11
The effect of surgical treatment for stress incontinence on OAB symptoms is conflicting. Studies have shown a decrease in prevalence of OAB symptoms postoperatively, but also a persistence of symptoms in more than one third of patients. Development of de novo OAB symptoms appears to be low.12,13
PFMT can improve OAB symptoms by up to 55%.14 Antimuscarinics have long-term symptom improvement of 60-70%,15 but side-effects are common and can affect compliance. Intravesical botulinum toxin A has 66-96% symptom improvement,16 but injections need to be repeated as the effect is reversible. Urinary retention secondary to detrusor hypotonia can also occur necessitating intermittent self-catheterisation until the effect wears off.
Neuromodulation techniques, such as sacral nerve stimulation, have shown short to medium term symptom improvement of 65-70%.17-19 OAB is generally a lifelong condition, but symptoms can be controlled with a combination of lifestyle changes, medication and/or neuromodulation.
Sextion 5: Case study
A 45-year-old woman presented with a five-year history of stress incontinence. Her symptoms had worsened recently, especially with coughing, sneezing and lifting. She experienced up to two episodes of incontinence per day and required the use of sanitary pads. The patient reported occasional coital incontinence that restricted the frequency of coitus.
Symptoms of urgency and frequency up to eight times per day were also reported.
The patient had a history of two vaginal deliveries (forceps) and no other significant medical problems or current medications. She had a BMI of 35 and smoked 10 cigarettes per day.
Examination by her GP revealed a negative urine dipstick test and first-degree uterine descent with a moderate anterior vaginal wall prolapse. Cough test was negative, and a pelvic floor tone of 2/5 in the Oxford scale.
After initial management involving lifestyle advice and referral to the continence adviser for PFMT and bladder retraining, the patient reported improvement of her stress incontinence symptoms and reduction in incontinent episodes to twice per week.
She still required the daily use of pads and had become more aware of urgency, despite completely abstaining from caffeinated beverages. An initial trial of oxybutynin immediate release (2.5mg twice a day) was abandoned after two months due to intolerable side-effects of dry mouth and constipation.
A second-generation antimuscarinic was prescribed in combination with a laxative, giving a satisfactory reduction in frequency with tolerable side-effects. The patient continued to have small volume episodes of incontinence twice per week but felt this was manageable. She had managed to reduce her BMI to 33 but continued to smoke.
Twelve months after initial referral, the patient reported the urgency to be well controlled, but the stress incontinence had worsened.
The patient was reviewed and referred for urodynamic assessment of the bladder. This confirmed both stress incontinence and detrusor overactivity. A day-case retropubic MUS procedure was accepted by the patient for further management of her stress incontinence.
At the six-week postoperative review by the GP, the patient was very happy with the results. She continued on her antimuscarinic for treatment of her OAB symptoms.
Section 6: Evidence base
- Ogah J, Cody JD, Rogerson L. Minimally invasive synthetic suburethral sling operations for stress urinary incontinence in women. Cochrane Database Syst Rev 2009 Oct 7; (4): CD006375. This supported the suggestion that MUSs were as effective as traditional methods in the short term, with fewer complications.
- Novara G, Artibani W, Barber MD et al. Updated systematic review and meta-analysis of the comparative data on colposuspensions, pubovaginal slings and midurethral tapes in the surgical treatment of female stress urinary incontinence. Eur Urol 2010; 58(2): 218-38.
- Anger JT, Weinburg A, Suttorp MJ et al. Outcomes of intravesical botulinum toxin for idiopathic overactive bladder symptoms: a systematic review of the literature. J Urol 2010; 183(6): 2258-64. This showed an improvement in idiopathic OAB refractory to medication, but a significant increase in post-void residuals and urinary retention.
- NHS Choices. Urinary incontinence
This article was reviewed and updated by Dr Julian Spinks a GP in Kent. The original article was first published in May 2014 and the authors are:
- Dr Alvaro Bedoya-Ronga, ST7, John Radcliffe Hospital, Oxford, UK
- Miss Wing Han Cheung, Locum consultant, John Radcliffe Hospital, Oxford, UK
- Mr Ian Currie, Consultant in obstetrics and gynaecology, Stoke Mandeville Hospital, Buckinghamshire, UK
- Irwin DE, Milsom I, Hunskaar S et al. Population-based survey of urinary incontinence, overactive bladder and other lower urinary tract symptoms. Eur Urol 2006; 50(6): 1306-14.
- Hunskaar S, Lose G, Sykes D et al.The prevalence of urinary incontinence in women in four European countries.BJU Int 2004; 93(3): 324-30.
- Sinclair AJ, Ramsay IN. The psychosocial impact of urinary incontinence in women. Obstet Gynaecol 2011; 13: 143-8.
- Resnick NM. Medical Grand Rounds 1984; 3: 281-90.
- Vasavada SP, Carmel ME, Rackley R. Medscape 2012 Apr(updated 2012 April 5).
- NICE. Urinary incontinence in women (CG171). September 2013.
- Felicissimo MF, Carneiro MM, Saleme CS et al.Intensive supervised versus unsupervised pelvic floor muscle training for the treatment of stress urinary incontinence: a randomized comparative trial. Int Urogynaecol J 2010; 21(7): 835-40.
- Chapple CR, Wein AJ, Brubaker L et al. Stress incontinence injection therapy: what is best for our patients? Eur Urol 2005; 48(4): 552-65.
- Lapitan MC, Cody DJ, Grant A. Cochrane Database Syst Rev 2009 Oct 7; (4): CD002912.
- Latthe PM, Foon R, Toozs-Hobson P.Transobturator and retropubic tape procedures in stress urinary incontinence: a systematic review and meta-analysis of effectiveness and complications. BJOG 2007; 114(5): 522-31.
- Abdel-Fattah M, Ford JA, Lim CP et al. Single-incision mini-slings versus standard midurethral slings in surgical management of female stress urinary incontinence: a meta-analysis of effectiveness and complications. Eur Urol 2011; 60(3): 468-80.
- Palva K, Nilsson CG. Prevalence of urinary urgency symptoms decreases by mid-urethral sling procedures for treatment of stress incontinence. Int Urogynecol J 2011; 22(10): 1241-7.
- Lee JK, Dwyer PL, Rosamilia A et al. Persistence of urgency and urge urinary incontinence in women with mixed urinary symptoms after midurethral slings: a multivariate analysis. BJOG 2011; 118(7): 798-805.
- Castro RA, Arruda RM, Zanetti MR et al. Single-blind, randomized, controlled trial of pelvic floor muscle training, electrical stimulation, vaginal cones, and no active treatment in the management of stress urinary incontinence.Clinics (Sao Paulo) 2008; 63(4): 465-72.
- Alhasso AA, McKinlay J, Patrick K et al. Anticholinergic drugs versus non-drug active therapies for overactive bladder syndrome in adults. Cochrane Database Syst Rev2006; 18(4): CD003193.
- Mangera A, Andersson KE, Apostolidis A et al. Contemporary management of lower urinary tract disease with botulinum toxin A: a systematic review of botox (onabotulinumtoxinA) and dysport (abobotulinumtoxinA). Eur Urol 2011; 60(4): 784-95.
- NICE. IPG64. Sacral nerve stimulation for urge incontinence and urgency-frequency. Issue date: June 2004.
- Peters KM, Carrico DJ, Perez-Marrero RA et al. Randomized trial of percutaneous tibial nerve stimulation versus Sham efficacy in the treatment of overactive bladder syndrome: results from the SUmiT trial. J Urol 2010; 183(4): 1438-43.
- NICE. IPG362. Percutaneous posterior tibial nerve stimulation for overactive bladder syndrome. Issue date: Oct 2010.