Understanding Urinary Incontinence
Dr. Grandinetti is a senior clinical research pharmacist at the National Cancer Institute, National Institutes of Health, Rockville, Maryland. The views expressed are those of the author and not those of any government agency.
Urinary incontinence (UI) is the lack of ability to control when you urinate. Anyone can get UI, but it occurs more often as people age and is more common in women. UI can lead to physical and social problems. The condition is uncomfortable and can cause embarrassment, isolation, and depression. It may also cause falls in older patients rushing to the bathroom. How the Bladder Works The body stores urine in the bladder. Three sets of muscles control urine: the bladder or detrusor, the sphincters, and the pelvic floor muscles. Normally, the bladder fills when the detrusor muscle relaxes and sphincters at the exit of the bladder are closed. When the bladder reaches a certain volume (about 6-12 ounces), chemical signals move from the spinal cord to the brain and cause an urge to go. When an individual urinates, the nervous system releases a chemical known as acetylcholine. Acetylcholine acts on the detrusor muscle, causing it to narrow. The sphincters open, and the bladder releases urine into a tube called the urethra that carries urine out of the body.
UI results from the following:
- An overactive bladder or lack of resistance in the urethra
- Not being able to empty the bladder because of something blocking it, like an enlarged prostate
- The bladder being unable to tighten
- A combination of these factors
Types of UI
The 3 common types of UI are:
- Stress urinary incontinence (SUI) is the accidental leakage of urine when doing things like coughing, sneez- ing, or standing, and is the most common type of UI in younger and middle-aged women. It can happen during pregnancy, at childbirth, and around the time of menopause.
- Overactive bladder (OAB), or urge incontinence, is being unable to delay urination; patients feel a strong need to go right before, or as, urine starts to leak. It happens when the detrusor muscle narrows even though the bladder is not full. This is more common in men.
- Mixed urinary incontinence (MUI) is a strong need to urinate and acci- dental leakage of urine with effort, sneezing, or coughing. This type is more common in men and elderly women.
Causes and Risk Factors
Many things cause UI, and they can be reversible or permanent (Table 1). Table 2 lists medications that can affect the muscles in the bladder or cause UI. Even though people are more likely to have UI when they are older, aging itself does not cause it. As people grow older, their bladders are not as elastic as they once were; they lose strength in their detrusor muscles; it becomes harder to delay urination; the urethra does not stay closed as easily; and the detrusor muscles narrow more often on their own. Other risk factors include having other medical problems, the brain not working normally, being unable to do everyday self-care activities without help, problems walking, being on diuretic therapy, having multiple childbirths, trauma, and obesity.
Treatment plans not involving drugs depend on the type of UI. Changed be - havior, such as bladder training, is useful for SUI, OAB, and MUI. Bladder training teaches patients to empty the bladder just before outings or when they per- form specific activities, such as eating or drinking. Eventually, it becomes a habit, and they can stop urine from leaking. Pelvic floor muscle exercises, called Kegels, can help patients with SUI and MUI. Kegels strengthen the muscles that control the bladder. Pessaries, small tampon-like plugs placed in the urethra, are also used to treat SUI in women.
For some patients with SUI, surgery may be the only helpful option. There are several types of surgery, which help some patients, but not others. A common surgery includes pulling up the blad- der and securing it in place. This holds up the bladder and makes the urethra narrower, so it will not leak. This does not work for everyone. Problems like being unable to release urine, injury to the bladder, bleeding, infection, chronic pain, and OAB can come from the surgery.
It is important for a doctor to know the correct type of UI that a patient has, because medicine for one type of UI could make things worse for anoth- er type of UI. Pseudoephedrine, phenylephrine, imipramine, and duloxetine are sometimes used, but they are not approved by the FDA for the treatment of SUI. They have not been proven to work, and these drugs could have unwanted effects. Pseudoephedrine and phenylephrine can cause people to not be able to sleep, feel worried or uneasy, have high blood pressure, experience a heartbeat that is not normal, and even have a stroke. Low doses of imipramine are used to treat both SUI and MUI. Elderly patients may have more side effects of imipramine, which include dry mouth, blurred vision, difficulty urinating, feeling dizzy, and feeling sleepy. Duloxetine can be toxic to the liver.
Anticholinergics are a class of drugs that can be used to treat OAB. They block acetylcholine's effect on the detrusor muscle. They include tolterodine (Detrol; Detrol LA), oxybutynin (Ditropan; Ditropan XL), oxybutynin transdermal system (Oxytrol), oxybutynin chloride 10% gel (Gelnique), fesoterodine fumarate (Toviaz), trospium (Sanctura), solifenacin (Vesicare), and darifenacin (Enablex). All of these drugs decrease the strong need to urinate and incontinence overall. Your prescriber will only recommend these drugs if you keep having symptoms even after changing your lifestyle and doing bladder training exercises.
The most common side effects of anticholinergics are blurred vision, dry mouth, difficulty urinating, headache, constipation, sleepiness, and confusion. These side effects, especially confusion and sleepiness, are of particular concern in the elderly. Caution is also needed in patients with untreated glaucoma, con- stipation, difficulty urinating, and gastro- intestinal disease. The extended-release (Detrol LA, Ditropan XL) and patch types (Oxytrol) may not cause as many side effects. Doses should be started low, especially in the elderly, and increased very slowly.
UI is difficult and can be embarrassing. Treatment methods without drugs often work well. If not, medication may help. No one has to live with this problem. Incontinence can be treated and often cured, and careful management can help you feel more relaxed and comfortable.