Overactive bladder (OAB) is a clinical syndrome comprising multiple urinary symptoms. It is defined by the International Continence Society (ICS) as ‘urinary urgency, usually accompanied by increased daytime frequency, and/or nocturia with or without urinary incontinence, in the absence of urinary tract infection or other detectable disease’. (Haylen et al, 2010).
Lower urinary tract symptoms including urgency, frequency, nocturia and incontinence are estimated to affect half of all adults at least weekly (Przydacz et al, 2020). Despite this statistic and a growing openness for discussion, urinary incontinence, defined as the involuntary passage of urine (Abrams et al, 2003) remains a taboo topic for many. The EPIC study, the largest international study to date, found the prevalence of OAB to be 11.8% with similar rates for men and women (Irwin et al, 2006).
Although prevalence of OAB increases with age in both sexes (Eapen and Radomski, 2016), it should not be seen as a consequence of normal ageing. It is associated with both physical and mental health problems including an increased risk of falls and fractures, skin and urinary tract infections, sleep disturbance, social isolation and depression (Brown et al, 2000).
OAB is often poorly recognised and under-diagnosed. Nurses are well placed to identify symptoms through observation of toileting habits and increasing care needs. They should discuss concerns with patients, their carers and other health professionals. This review will provide an overview of the diagnosis and management of OAB, to raise awareness of this important condition and strengthen discussions between healthcare staff and patients.
Diagnosis
OAB is a clinical diagnosis based on the symptoms of urinary urgency, urge incontinence, frequency and nocturia. Bladder diaries are helpful for quantifying these symptoms and can be used to set achievable goals for treatment and to assess improvement with treatment over time. A 3-day bladder diary is recommended and should ideally include a range of usual activities such as work, leisure days and exercise (Clement et al, 2013). An example of this is the International Consultation on Incontinence Questionnaire (ICIQ) Bladder Diary available online (Corcos et al, 2002). It should be noted that bladder diaries reveal a wide range of ‘normal’ voiding patterns making it difficult to define standardised ‘normal’ parameters for comparison (Amundsen et al, 2007).
A diagnosis of OAB can usually be made based on symptoms without the need for additional investigations. Urodynamic studies are generally reserved for cases of diagnostic uncertainty, or when surgical treatments are being considered (National Institute for Health and Care Excellence (NICE), 2019). Urodynamic studies, which involve the insertion of pressure-monitoring bladder and vaginal/rectal catheters, can be used to confirm detrusor overactivity, which is the hallmark finding in OAB. An urge to void despite low bladder volumes and observed urinary incontinence are also suggestive of OAB.
Conservative treatment options for OAB
Treatment of OAB is not curative, though many treatment options exist to reduce symptoms and improve quality of life. It is important to establish realistic goals and expectations with each patient. Treatment options are best approached in a stepwise manner, starting with conservative measures, which are recommended by all existing guidelines. Further investigations are often required before progressing to more invasive options, which typically have more associated side effects (Table 1).
Table 1. Treatment options for overactive bladder
| Conservative |
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| Medical |
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| Minimally invasive |
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| Major reconstructive surgery |
|
Many people find incontinence embarrassing and isolating but find reassurance from support groups in person or online. Printed or digital ‘Just Can't Wait’ cards (now available as a mobile phone download) are discreet and convenient tools that patients can use to request the use of a toilet urgently; applications can be made online through the Bladder and Bowel Community website (Bladder and Bowel Community, 2022a). Patient information leaflets are also helpful and can be found locally or online on the British Association of Urological Surgeons' website (https://www.baus.org.uk/patients/information_leaflets).
For some, OAB causes significant psychological morbidity in addition to the direct physical symptoms, resulting in reduced quality of life, reduced work productivity and increased anxiety and depression (Coyne et al, 2011a). Research has also shown OAB to be associated with a reduction in sexual health including the enjoyment of sex (Coyne et al, 2011b). It is very important that these often highly distressing symptoms are explored with patients and psychological support offered alongside direct treatment of OAB.
Containment devices can provide reassurance to those with incontinence, thereby improving quality of life. They include absorbent products, protective garments and toileting aids. However, due to the expense of long-term use and the potential loss of dignity perceived with these products, NICE (2019) recommends them only in three situations: as a coping strategy pending definitive treatment, in addition to active treatments or where other treatment options have been deemed unsuitable. Bladder and bowel care teams can provide advice and support regarding these products if required.
Modifying fluid intake can be helpful in some patients for improving OAB symptoms. Use of a bladder diary helps to provide some more objective evidence to accurately access daily fluid intake, as volumes appear to correlate with urinary frequency, leakage and urgency (Wyman et al, 1991; Hashim and Abrams, 2008), and fluid restriction may improve these symptoms in some people (Swithinbank et al, 2005). However, fluid restriction should be undertaken cautiously, as dehydration may also exacerbate OAB symptoms; smaller volumes of concentrated urine can be irritating to the bladder and increase the risk of urinary tract infections (UTIs). It is also well recognised that daily fluid intake in the elderly is often low (Frangeskou et al, 2015) and so additional care to avoid dehydration in this group is important. NICE (2019) recommends patients with a high or low fluid intake should be counselled to modify their fluid intake and this advice should be individualised to promote compliance.
Research suggests caffeine may also contribute to OAB symptoms although evidence for the benefit of caffeine reduction is weak. Caffeine can be found in drinks such as coffee, tea and hot chocolate. It is excreted in urine and may promote bladder irritability, urgency and frequency. Two randomised controlled trials have shown symptomatic benefit from reducing caffeine consumption (Bryant et al, 2002; Wells et al, 2014) but a meta-analysis of observational studies failed to demonstrate an association between level of caffeine consumption and symptoms (Sun et al, 2016). Despite conflicting evidence, clinical guidelines generally recommend a trial of caffeine reduction (Nambiar et al, 2018; NICE, 2019).
Alcohol and carbonated drinks have also been hypothesised to contribute to OAB, but strong evidence for a causal link is lacking. Observational data on the association between alcohol and urinary incontinence has been contradictory (Hannestad et al, 2003; Maserejian et al, 2012; Przydacz et al, 2020). Carbonated drink consumption has been independently associated with development of OAB in women in one observational study (Dallosso et al, 2003). However, in the absence of high-quality clinical trials evaluating the efficacy of alcohol and carbonated drink reduction, it is not possible to make firm recommendations. Instead, patients could be counselled that these substances might exacerbate symptoms in some people.
Obesity and an increased body fat percentage is recognised to worsen urinary incontinence (Whitcomb and Subak, 2011; Hagovska et al, 2020) due to increased intra-abdominal pressure exerted on the pelvic floor. NICE (2019) recommends weight loss for those with a body mass index (BMI) over 30 kg/m2.
Pelvic floor muscle training improves incontinence by strengthening the muscles surrounding the urethra enabling a stronger ‘squeeze’ and ability to hold on to urine for longer. Kegel exercises of at least eight pelvic floor muscle contractions at least three times a day are recommended (NICE, 2019). Trained professionals such as GPs and bladder and bowel care specialist nurses are able to assess muscle tone on contraction; for those who experience difficulties with isolating these muscles, supervised pelvic floor training should be considered over a duration of at least 3 months (NICE, 2019).
Many people with OAB toilet frequently due to the repeated sensation of needing to urinate and the hope of reducing incontinence. Bladder retraining focuses on teaching individuals to hold onto their urine for longer by progressively delaying bladder emptying over a number of weeks (British Association of Urological Surgeons, 2020). This increases the bladder volume while changing behaviours around toileting. Holding a pelvic floor squeeze and distraction techniques are both recommended methods for bladder retraining. The aim is to extend urination to intervals of 3-4 hours intervals where possible. Bladder and bowel care teams can support patients with this.
Medical therapies for the treatment of OAB
It is recognised that during the menopause, oestrogen production declines with resultant thinning and atrophy of the vaginal and urethral mucosa. This may cause symptoms such as vaginal dryness and irritation, dyspareunia (pain during sex) and increased infections (Ostle, 2015). External signs of vaginal atrophy include a narrow vaginal opening, sparse pubic hair, flattened or fused labia, fissuring and erythema (Ostle, 2015) and these may be observed by healthcare staff during personal care. NICE (2019) recommends intravaginal oestrogen therapies to treat symptoms of OAB in post-menopausal women with vaginal atrophy; these include vaginal tablets, creams and pessaries. Those with additional symptoms of the menopause should be referred to their GP for consideration of hormone replacement therapy.
Antimuscarinics, a subtype of anticholinergic medications, work by binding to the M2 and M3 muscarinic receptors on smooth muscle fibres in the detrusor muscle, blocking the neurotransmitter acetylcholine and preventing detrusor contraction. It may take 4-6 weeks to see any improvement in symptoms, and common side effects that should be discussed with patients include dry mouth, constipation, urinary retention and cognitive impairment. Much research has focused on anticholinergics and their association with cognitive impairment (Gray et al, 2015). Although they should be avoided in the over 65s for this reason, an individualised assessment including current quality of life and total anticholinergic burden in the context of polypharmacy should always be considered; the Anticholinergic Burden calculator (www.acbcalc.com) can be helpful when assessing this. Oxybutynin and tolterodine should be avoided in older adults due to their stronger association with cognitive impairment; trospium is favoured as theoretically it does not cross the blood-brain barrier (Duong et al, 2021).
NICE (2019) states that mirabegron should be considered when antimuscarinics are contraindicated, not tolerated or ineffective. It is a beta-3-adrenergic-receptor agonist that works by relaxing detrusor smooth muscle during the storage phase, which increases the bladder's storage capacity thereby alleviating urgency and frequency. Side effects include a dose-dependent tachycardia and hypertension therefore it is contraindicated if the blood pressure exceeds 180/110 mmHg (Joint Formulary Committee, 2022a). In practice it is commonly prescribed in combination with an anticholinergic following the findings of the BESIDE study; this showed a reduction in urinary incontinence secondary to OAB in those prescribed solifenacin and mirabegron in combination when solifenacin alone did not stop incontinence (Drake et al, 2016).
Nocturia, defined by the ICS as ‘the number of times urine is passed during the main sleep period, with each urination followed by sleep or the intention to sleep’ (D'Ancona et al, 2019) is an under-reported symptom often mistaken for a normal part of ageing. The EPIC study reported the prevalence in adults to be 48.6% in men and 54.5% in women (Przydacz et al, 2020). The sensation of a full bladder can lead to awakening and a disruption of sleep understood to lead to reduced quality of life and difficulties in health, relationships and work lives (Weiss et al, 2013). Although high-quality evidence for its benefit is lacking, fluid restriction in the 4 hours before bed is widely advocated by experts to reduce nocturia. It should be noted that certain foods such as fruits, salads and soups also contain a high water concentration and should also be restricted in the evenings.
In those with peripheral oedema, elevation of the legs at night may cause increased venous return with fluid draining from the legs into the circulation, which is then filtered by the kidneys, increasing urine production and subsequent nocturia. A loop diuretic such as furosemide taken in the late afternoon is off-licence use but widely recognised to increase diuresis in the evening thus reducing the more troublesome nocturia. There is a lack of trial-based evidence surrounding this use of diuretics; however, the NICE guideline development group came to the consensus that a trial of late afternoon loop diuretics to improve quality of life for men with lower urinary tract symptoms (LUTS) is appropriate (NICE, 2015). Interestingly, there is no similar suggestion for women, although the medication may be trialled with the agreement of the patient.
Desmopressin is a synthetic antidiuretic hormone that increases water reabsorption in the kidneys and causes urine to concentrate, therefore reducing urine volumes and frequency. It is recommended for the treatment of nocturia with caution in those over 65 years and with cardiovascular disease due to the risk of hyponatraemia (low sodium), particularly in the elderly (Joint Formulary Committee, 2022b). More recently the ICS consensus listed contraindications of hyponatraemia (Na <130 mmol/litre), heart failure, polydipsia and concomitant medications with a high risk of hyponatraemia. When prescribing, the delicate balance of potential adverse effects versus the positive impact on quality of life must be considered.
Minimally invasive treatments for OAB
Where conservative and medical therapies have failed to significantly improve symptoms of OAB, NICE (2019) recommends referral to a specialised multidisciplinary team (MDT) for consideration of surgical treatments. In practice it is at this stage that further specialist investigations, such as urodynamic studies, are indicated if clinically appropriate.
Botulinum toxin (Botox) blocks the release of acetylcholine at the neuromuscular junction preventing detrusor muscle contraction (Nigam and Nigam, 2010). Intravesical Botox is performed by urologists during cystoscopy using local anaesthetic. Symptom improvement is usually noted after 3-21 days with positive effects lasting up to 6-9 months (Granese et al, 2012) although there is wide variation in patient response with symptomatic benefit in some lasting up to 18 months. By temporarily paralysing the detrusor muscle, there is a high chance of incomplete bladder emptying and urinary retention that may be temporary or last the duration of the Botox. Approximately 5-7% of patients require either self-catheterisation or an indwelling catheter until the effects of Botox wear off (Cox and Cameron, 2014; Sievert et al, 2014). NICE (2015; 2019) recommends Botox for men and women with detrusor overactivity who have not responded to conservative and medical treatments.
Sacral nerve stimulation, also known as sacral neuromodulation, involves an electrode being inserted into the lower back that sends impulses to the sacral nerves preventing bladder contraction. The electronic device is approximately the size of a £2 coin and inserted under the skin in the upper buttock (Bladder and Bowel Community, 2022b). Sacral nerve stimulation can interfere with radiological imaging and diathermy so should always be listed in the past medical history. Sacral nerve stimulation could be considered in refractory OAB patients with recurrent UTIs or those who also suffer with faecal symptoms including incontinence.
Posterior tibial nerve stimulation involves neuromodulation of the S3 nerve and is another alternative treatment option in refractory OAB, although there is a lack of long-term data.
Major reconstructive surgery
Surgical treatment options are generally reserved for the most symptomatic individuals and should be determined by an MDT. Augmentation enterocystoplasty entails cutting the bladder open and grafting the bowel to it to increase the bladder volume thereby reducing the symptoms of detrusor contraction. Urinary diversion involves creation of an ileal conduit or surgical removal of the bladder and replacement with a new bladder formed from a section of bowel (‘neo-bladder’). These treatment options carry anaesthetic and surgical risks as well as lifestyle changes such as the need to be competent in self-catheterisation. Careful consideration should therefore be given to patient selection using frailty assessment tools such as the Clinical Frailty Score (Rockwood et al, 2005) as well as the expertise of the MDT including the clinical nurse specialist.
Conclusion
OAB carries significant morbidity and can have a devastating effect on quality of life. There are many treatment options available including conservative, medical and surgical options and even small changes can make an enormous difference to someone's life. All patients should be encouraged to discuss their bladder health and its impact on their quality of life, and not to consider it a part of normal ageing. Discussions around continence must become normalised.
KEY POINTS
- Overactive bladder is a clinical diagnosis based on the symptoms of urinary urgency with or without urinary incontinence, frequency and nocturia
- It is common with a prevalence of around 12% but is often under-reported due to embarrassment or the perception of it being a normal part of ageing
- Conservative treatment options include modifying fluid intake, a reduction in caffeine, alcohol and carbonated drinks, weight loss, pelvic floor muscle exercises and bladder retraining
- Anticholinergic medications (antimuscarinics) can improve symptoms but are associated with side effects that include a dry mouth, constipation, urinary retention and cognitive impairment
- More invasive treatment options include intravesical Botulinum toxin, sacral neuromodulation, augmentation enterocystoplasty and ileal conduit urinary diversion; these should only be considered following recommendation from a specialist multidisciplinary team
CPD reflective questions
- How might you introduce a discussion on incontinence with someone in your care?
- If you suspect a diagnosis of overactive bladder, who could you refer a patient to for further support?
- Which treatment options would you consider for a young person in good health, in comparison with an older person with frailty?