(Published March 2011)
Introduction to Overactive Bladder
- Overactive bladder (OAB) is a term first used in the 1990s to describe a constellation of lower urinary tract symptoms (LUTS).
- OAB is prevalent and significantly affects patients’ quality of life.
- OAB is urinary urgency (with or without urinary incontinence), urinary frequency, and nocturia, in the absence of proven infection or other obvious pathology.1
- Urinary urgency is a compelling urge to urinate that is difficult to defer.2
- Urinary frequency is defined as voiding more than eight times in 24 hours.3,4
- Nocturia is defined as awakening more than one time per night to void.5
- The symptoms of OAB are suggestive of urodynamically demonstrable detrusor overactivity, although they can be due to other forms of urethro-vesical dysfunction.1
- OAB is also thought to result from changes in the afferent nerve endings in the bladder that increase bladder sensation.6
- Approximately 17 percent of adults more than 18 years old have OAB.7-9
- The prevalence of OAB increases with age among both men and women.
- One third of patients with OAB have incontinence.8
- As many as 45 percent of women will have urinary incontinence in their lifetime.10
Types of urinary incontinence
- Urge urinary incontinence (UUI) is incontinence characterized by a compelling need to urinate
- Stress urinary incontinence (SUI) is incontinence during sudden increases in intra-abdominal pressure (cough, sneeze)
- Mixed urinary incontinence is a combination of stress and urge incontinence
- Several conditions are significantly more frequent among patients with OAB than among control subjects; the most prevalent comorbidities are urinary tract infections (UTIs), falls, and fractures.11
- In one study:12
- Of women more than 65 years old who had urge incontinence at least once per week, 19 to 42 percent sustained falls.
- Fractures occurred in 4 to 9 percent of these falls.
- Frequent urge incontinence was an independent risk factor for falling (OR = 1.26).
Impact of incontinence
- Impact on patients:
- Psychological—People with OAB may become depressed because of their symptoms, and some feel guilty. The embarrassment of leaking or smelling of urine can lead to a loss of self-respect and dignity.
- Social—OAB sufferers might restrict social activity outside the home for fear of leaking urine or because of the frequent need to use a toilet.
- Domestic—Some individuals with OAB use specialized undergarments and bedding materials for incontinence. These items can be costly and are not always covered by medical insurance.
- Occupational—Overactive bladder may lead to decreased productivity in the workplace. Some patients may avoid going to work for fear of leaking urine.
- Sexual—Women with OAB have reported avoiding dating and sexual intimacy because of overactive bladder symptoms and fear of leaking urine.
- Physical—Some physical activities like exercising might be limited because of the frequent need to urinate or fear of leaking urine.
- Impact on society:
- Cost—$12.6 billion was spent on therapy for OAB in 2000 ($9.1 billion spent for community residents and $3.5 billion for institutional residents).13
- Missed opportunities for treatment
- More than 50 percent of patients who seek treatment for OAB wait more than a year before seeing a health care provider.14,15
- Despite the widespread prevalence of OAB, its impact on quality of life, and its overall morbidity, this condition remains undiagnosed and undertreated for many patients.
- Patient-related causes:7,16,17
- Failure to see symptoms as abnormal
- Belief that symptoms are self-limited
- Perception of lack of treatment efficacy
- Fear of procedure
- Patient-related causes:7,16,17
- Fear of cost of treatment
- Clinician-related causes: 7,16,17
- Misperception that symptoms are not important to the patient (perhaps because the patient does not volunteer information or complaints)
- Misperception that OAB is a natural part of aging
- Misperception that treatment is ineffective
- Lack of awareness of the differential diagnosis
- Lack of appreciation for the impact on quality of life
- Failure to consider potential complications, including:
- Skin infections
- Falls and fractures
- Clinician-related causes: 7,16,17
Differential diagnosis in women
- There are a limited number of ways the bladder can express its pathology.
- Thus, the symptoms seen with OAB can have a number of different underlying causes, including:18
- Uro-gynecologic conditions
- Bladder cancer
- Neurogenic bladder
- Interstitial cystitis
- Pelvic organ prolapse
- Postsurgical complication
- Stress incontinence
- Urethral diverticulum
- Urinary tract infection
- General medical conditions
- Congestive heart failure
|Leaking duringphysical activity||Sometimes||Yes||No|
|Amount of leakage||Variable||Variable||Small|
|Urinalysis & culture||Normal||Normal||Abnormal|
- A simple symptom assessment can help differentiate among OAB, stress incontinence, and urinary tract infection.
- Both OAB and UTI are accompanied by urinary urgency, frequency, and urge incontinence, but most patients with UTI also have dysuria, and all have pyuria or hematuria and a positive urine culture.
- Stress incontinence is not a symptom of OAB, but about one third of patients with SUI also have urge incontinence.19
- Abrams P, Cardozo L, Fall M, et al. The standardisation of terminology of lower urinary tract function: report from the Standardisation Sub-committee of the International Continence Society. Neurourol Urodyn. 2002;21(2):167-78.
- Chapple C. Classification of mixed incontinence. Eur Urol. 2006;5(16)837-41.
- Fitzgerald MP, Brubaker L. Variability of 24-hour voiding diary variables among asymptomatic women. J Urol. 2003;169(1):207-9.
- Fitzgerald MP, Stablein U, Brubaker L. Urinary habits among asymptomatic women. Am J Obstet Gynecol. 2002;187(5):1384-8.
- van Kerrebroeck P, Abrams P, Chaikin D, et al. The standardisation of terminology in nocturia: report from the standardisation Sub-committee of the International Continence Society. Neurourol Urodyn. 2002;21:179–83.
- Yoshida M, Masunaga K, Nagata T, et al. The forefront for novel therapeutic agents based on the pathophysiology of lower urinary tract dysfunction: pathophysiology and pharmacotherapy of overactive bladder. J Pharmacol Sci. 2010;112(2):128-34.
- Milsom I, Abrams P, Cardozo L, et al. How widespread are the symptoms of an overactive bladder and how are they managed? A population-based prevalence study. BJU Int. 2001;87(9):760–6.
- Stewart W, Herzog R, Wein A. The prevalence and impact of overactive bladder in the U.S.: results from the NOBLE program. Neurourol Urodyn. 2001;20:406-8.
- Stewart WF, Van Rooyen JB, Cundiff GW, et al. Prevalence and burden of overactive bladder in the United States. World J Urol. 2003;20(6):327-36.
- Buckley BS, Lapitan MC; Epidemiology Committee of the Fourth International Consultation on Incontinence, Paris, 2008. Prevalence of urinary incontinence in men, women, and children—current evidence: findings of the Fourth International Consultation on Incontinence. Urology. 2010;76(2):265-70.
- Darkow T, Fontes CL, Williamson TE. Costs associated with the management of overactive bladder and related comorbidities. Pharmacotherapy. 2005;25(4):511-9.
- Brown JS, Vittinghoff E, Wyman JF, et al. Urinary incontinence: does it increase risk for falls and fractures? Study of Osteoporotic Fractures Research Group. J Am Geriatr Soc. 2000;48(7):721-5.
- Hu TW, Wagner TH, Bentkover JD, et al. Costs of urinary incontinence and overactive bladder in the United States: a comparative study. Urology. 2004;63(3):461-5.
- Harris Interactive. Harris Interactive survey examines a not-so-talked-about health issue affecting intimacy for many. Health Care News. June 7, 2001; 1(18).
- Dmochowski RR, Newman DK. Impact of overactive bladder on women in the United States: results of a national survey. Curr Med Res Opin. 2007;23(1):65-76.
- Milsom I, Stewart W, Thüroff J. The prevalence of overactive bladder. Am J Manag Care. 2000;6(11 Suppl):S565-73.
- Ricci JA, Baggish JS, Hunt TL, et al. Coping strategies and health care-seeking behavior in a US national sample of adults with symptoms suggestive of overactive bladder. Clin Ther. 2001;23(8):1245-59.
- Rosenberg MT, Newman DK, Tallman CT, Page SA. Overactive bladder: recognition requires vigilance for symptoms. Cleve Clin J Med. 2007;74(Suppl 3):S21-9.
- Abrams P, Wein AJ. The Overactive Bladder: A Widespread and Treatable Condition. Stockholm, Sweden: Erik Sparre Medical AB; 1998.
About Audrey Kelly, PharmD