Overactive Bladder Syndrome

What is an Overactive Bladder?

Overactive bladder (OAB) syndrome is a bladder-storage disorder characterized by the following bladder symptoms:

1. Urgency – complaint of a sudden desire to pass urine which is difficult to defer. Sometimes, an involuntary leakage of urine may occur (urge urinary incontinence).
2. Daytime urinary frequency – complaint of voiding (during waking hours) more than previously considered normal (usually > 7 times)
3. Nocturia – complaint of waking up (at night) at least once because of the need to void

What are the causes and risk factors of an Overactive Bladder?

There are several conditions that may cause the signs and symptoms of OAB, such as:

1. Aging - OAB can affect women of any age, but it occurs more often in older adults. Still, OAB should not be considered a normal part of aging.
2. Urinary Tract Infection
3. Atrophic vaginitis – inflammation of the vagina secondary to estrogen deficiency
4. Bladder stones or tumors
5. Excessive consumption of caffeine or alcohol
6. Diabetes mellitus
7. Medications (diuretics, psychotropics)
8. Restricted mobility
9. Neurological disorders (Parkinson’s disease, Alzheimer’s, Multiple sclerosis) 

Oftentimes, the exact cause of OAB is not known. 

What happens when you have an Overactive Bladder?

Normally, the bladder can store a significant volume of urine (400-600ml) before it signals the need to empty itself. As the bladder muscles gradually stretch during filling, it sends intermittent signals to the brain, and you get the feeling of wanting to pass out urine. If it is not a convenient time to void, the brain signals back, and the bladder muscles remain relaxed, the urethral and pelvic floor muscles keep contracting, and you are able to hold your urine. When you decide that you already want to urinate, your brain sends nerve signals that coordinate the relaxation of the pelvic floor and urethral muscles, and the contraction of the bladder muscles which forces urine out.

In OAB, there is a problem with the nerves and muscles of the bladder resulting in inappropriate or untimely bladder contractions even when the volume of urine in the bladder is low. These spasms cause the sudden urge to rush to the bathroom, which may even lead to leakage.

How is OAB diagnosed?

A detailed medical history is first obtained to identify potential risk factors. Your doctor may also need to perform a focused neurological examination to identify other possible conditions.

Other tests may include:

1. Urinalysis – to assess for any infection of the urinary tract
2. Residual urine – a bladder scan or a catheter may be used to assess the volume of urine left inside your bladder after you urinate. A high residual may cause symptoms of OAB.
3. Urodynamic tests – measures the bladder capacity and pressure, and can evaluate how effectively your bladder can empty itself.

You may also be asked to keep a voiding or bladder diary to assess your baseline urinary habits. This is a record of the amount of fluid you drink, the number of voids you make, and the amount of leakage (if any) that happens in a day.

What are the available treatment options?

Behavioral treatment is initially advised. This includes:

1. Lifestyle change – Certain food and drinks may cause you to urinate more often. Avoiding caffeinated drinks like coffee, tea and cola may help control frequency. The same holds true for alcoholic beverages. If you have nocturia, avoiding too much fluid a few hours before you sleep may also help. Weight loss may be beneficial in relieving the extra pressure placed on the bladder. Smoking has also been considered a bladder irritant so cutting out on smoking may alleviate some symptoms.
2. Bladder training – The first step is by completing a bladder diary. This helps you study your pattern of voiding and leaking, as well as assess how much fluid intake you have and if it affects your urine frequency. With this information, you can time when you have to go the bathroom, as well as adjust your intake in order to avoid frequent voiding or accidental leakage.
3. Pelvic floor muscle exercises – this is called the Kegel exercise, and the most essential part of the exercise is making sure that the right muscles are being used. Your doctor may help to make sure you are squeezing the right muscles. Strengthening these muscles and knowing the right time to squeeze them help in controlling the leaks that occur due to urgency. Some symptoms of OAB may improve after 3 to 6 months of regular pelvic floor muscle exercises.

In cases where behavioral treatment is only partially effective, additional pharmacologic treatment may be given. These include:

1. Anticholinergic medications – these are drugs which help relieve symptoms of OAB by relaxing the muscles of the bladder
2. Hormonal therapy - some of the symptoms of OAB may be caused by estrogen deficiency so these may be relieved by hormone replacement therapy
3. Botulinum Toxin A – also known as Botox. It is injected in small doses into the bladder muscles, partially paralyzing it, thereby increasing bladder capacity and decreasing involuntary contractions. 

At The Medical City, what are the related services available for OAB?

At The Medical City, we have a complete roster of competent urogynecologists who can assess and treat patients with overactive bladder. A comprehensive urodynamic evaluation is offered for patients with OAB at the Pelvic Floor Center with the following services:

1. simple office cystometrogram
2. uroflowmetry
3. multi-channel cystometry
4. urethral function test (urethral pressure profilometry)
5. electromyography (EMG)
6. pelvic floor ultrasound
7. bladder scan
8. cystourethroscopy

References:

• Bump Richard C. et al. The standardization of terminology of female pelvic organ prolapse and pelvic floor dysfunction. Am J Obstet Gynecol 1996; 175: 10-7.
• Walters, Mark D and Mickey M. Karram. Urogynecology and Reconstructive Pelvic Surgery Fourth Edition. Philadelphia: Saunders, 2015.
• International Urogynecological Association (IUGA) website.
• Department of Obstetrics and Gynecology – Section of Urogynecology
• Center for Patient Partnership