Urinary incontinence (UI), the involuntary leakage of urine, is a frequent and problematic chronic condition for many patients. An estimated 10 to 30% of men and women are affected nationally, though this may be underestimated due to underdiagnoses and undertreatment.1-3
Often, patients who suffer with UI symptoms will develop poor self-rated health, depression, and mobility disability.4,5 This comorbid disease state also presents a substantial financial burden; data from 2014 found that in the United States alone, an estimated $65.9 billion in direct and indirect costs were spent for UI treatment.3
UI can present as transient and reversible, or it can be established and chronic. There are four main types of UI–stress, urge, overflow, and functional incontinence.6 These incontinence subtypes differ based on the symptom presentation as shown in Table 1. Based on definitions from the Abrams et al. report (2002), stress incontinence is defined as the “involuntary loss of urine on effort or physical exertion or on sneezing or cough.” Urge incontinence is the “complaint of involuntary leakage accompanied by or immediately preceded by urgency.”6 Overactive bladder (OAB) is a disorder associated with a feeling of urgency and frequency and can lead to urge incontinence if a patient has associated urinary leakage; therefore all patients with urge incontinence will have OAB, but not all patients with OAB will have urge incontinence.7
Overflow incontinence is related to an obstructed urine flow and/or bladder underactivity where an individual has a full bladder, but is unable to completely void at time of urination, which later leads to leakage (i.e., benign prostate hyperplasia).8 Functional incontinence, unlike the other forms of incontinence, occurs when an individual has issues getting to the restroom due to an external factor (i.e. dementia, immobility, etc.), but is not associated with urinary tract dysfunction.8 This article will highlight the diagnosis and treatment of urge urinary incontinence (UUI) and OAB.
Risks Factors, Cause, and Diagnosis of UUI/OAB
While the UUI/OAB is primarily associated with advanced age, other risk factors identified include educational status, neurologic diseases like prior stroke, elevated body mass index (BMI), recurrent urinary tract infections (UTIs), and positive metabolic screening, which factors in hypertension and diabetes diagnosis, waist-to-hip ratio, and elevated triglycerides.10-12 The specific mechanism which causes UUI/OAB is unknown, however in patients with this condition, urodynamic control is not well regulated.7 The main muscle of the bladder, the detrusor muscle, will involuntary contract—regardless of the bladder volume—which leads to the urge to urinate. These involuntary contractions are caused by increased smooth muscle excitability and stimulation and/or changes in bladder innervation.7