Diagnosis and Management of Overactive Bladder – Introduction

(Published March 2011)

Introduction to Overactive Bladder

Overview

• 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.

Definitions

• 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

Pathophysiology

• 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

Prevalence

• 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

Comorbid conditions

• 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
    • Embarrassment
    • Failure to see symptoms as abnormal
    • Belief that symptoms are self-limited
    • Perception of lack of treatment efficacy
    • Fear of procedure
• 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:
    • Depression
    • Skin infections
    • Falls and fractures

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
    • Polyuria/polydipsia
    • Diabetes
    • Congestive heart failure
    • Medications

• 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

References

1. 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.
2. Chapple C. Classification of mixed incontinence. Eur Urol. 2006;5(16)837-41.
3. Fitzgerald MP, Brubaker L. Variability of 24-hour voiding diary variables among asymptomatic women. J Urol. 2003;169(1):207-9.
4. Fitzgerald MP, Stablein U, Brubaker L. Urinary habits among asymptomatic women. Am J Obstet Gynecol. 2002;187(5):1384-8.
5. 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.
6. 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.
7. 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.
8. 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.
9. 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.
10. 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.
11. Darkow T, Fontes CL, Williamson TE. Costs associated with the management of overactive bladder and related comorbidities. Pharmacotherapy. 2005;25(4):511-9.
12. 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.
13. 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.
14. 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).
15. 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.
16. Milsom I, Stewart W, Thüroff J.  The prevalence of overactive bladder. Am J Manag Care. 2000;6(11 Suppl):S565-73.
17. 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.
18. 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.
19. Abrams P, Wein AJ. The Overactive Bladder: A Widespread and Treatable Condition. Stockholm, Sweden: Erik Sparre Medical AB; 1998.