Bladder problems, such as urinary frequency, can be a frustrating and embarrassing effect of PD-related symptoms. The bladder is a smooth muscle, called the detrusor, which is shaped like a hollow pyramid with its apex pointed down. The bladder does not contract voluntarily like your arm and leg muscles. Rather it contracts and relaxes in response to how much urine it holds. Normally, your bladder holds approximately 650 ml of urine.
As you age, your bladder becomes less elastic and only holds half as much urine. Contraction of the bladder is regulated by the chemical messengers, norepinephrine and acetylcholine. For your bladder to empty, contraction of the detrusor must be accompanied by relaxation or opening of two sphincters or “locks.”
The contraction of your internal sphincter is involuntary, while the contraction of your external sphincter is voluntary; this is what allows you to hold your urine until you reach a bathroom. The contraction of both sphincters is under the control of acetylcholine. If the time and place for urination is appropriate, your conscious brain, your urination center, and your autonomic nervous system (ANS) all work together to contract your bladder and at the same time relax your internal and external sphincters and the voluntary muscles of your pelvic floor to allow you to urinate.
If your urination center or ANS malfunctions, as either might in PD, you may have symptoms of an overactive bladder, depending on the degree to which the different parts of your nervous system are affected. Less commonly, you might experience symptoms of an underactive (hypoactive or hypotonic) bladder or both an overactive and underactive bladder. In men, an enlarged prostate gland may block the flow of urine. In women, lax pelvic muscles (from child-bearing) may cause incontinence (involuntary loss of urine). The following are the more common symptoms of bladder malfunction in PD:
Frequency, a symptom of an overactive bladder, is a need to void many times, eight or more times a day.
Hesitancy, a symptom of an overactive bladder, is defined as a lag period, several seconds to minutes, between the time you want to void and are at the toilet, but are unable to do so.
Incontinence, an accidental or involuntary loss or leakage of urine. Incontinence may be a symptom of an overactive bladder: you have the urge to void, but can’t get to the toilet in time. Or it may be a symptom of a hypotonic bladder, called overflow incontinence: urine escaping from a full bladder through a lax sphincter.
Stress incontinence is loss of urine that occurs with coughing, crying, laughing, or sneezing. These activities increase pressure in the abdomen, forcing urine through a lax sphincter.
Nocturia, two or more trips to the bathroom at night is usually a symptom of an overactive bladder or an enlarged prostate or both. At night, when you lie down, your bladder assumes a recumbent position. Instead of concentrating at the bladder-neck, urine spreads out over a larger surface which “fools” your ANS into believing your bladder is fuller than it is. In many people, nocturia causes difficulty sleeping. To minimize nocturia do not drink anything at night and try to avoid alcohol, which is a diuretic. You may also want to try sleeping in an upright position, as this concentrates urine in your bladder neck.
Retention, an inability to void, is a symptom of an underactive or hypotonic bladder. Total inability to void is an emergency and requires catheterization, the insertion of a thin walled tube into the bladder through the urethra.
If you have symptoms of an overactive or hypotonic bladder, you should consult a doctor, preferably a urologist. He or she will give you an examination that includes a urine analysis to rule out an infection. Exams also include blood tests to screen for kidney disease and diabetes. In men, it will include a rectal examination to assess the prostate gland. In women, it will consist of a pelvic examination to assess the bladder, uterus, the relationship of the uterus to the bladder, and firmness of the pelvic muscles. Treatment for bladder concerns varies depending on the nature of the problem.
A urologist can prescribe drugs to relax the bladder and sphincters of an overactive bladder. Acetylcholine blockers such as darifenacin (Enablex), oxybuynin (Ditropan), solifenacin (Vesi-care), tolterodine (Detrol), and trospium (Sanctura) work to relax the bladder muscles, but may cause side effects such as dry mouth, blurred vision, constipation, a rapid heartbeat, and flushing, due to blocking the actions of acetylcholine at other sites. In older patients, and some patients with PD, side effects may include confusion, disorientation, delusions, hallucinations, and memory loss. These particular side effects can mimic dementia, but are reversible upon stopping the drugs.
However, Enablex and Sanctura do not cross into the brain and do not cause side effects that mimic dementia. Norepinephrine blockers, such as tamsulosin (Flomax), doxazosin (Cardura), terazosin (Hytrin), and alfuzosin (UroXatral) also relax the bladder. Side effects from blocking the actions of norepinephrine at other sites can include low blood pressure, which results in dizziness and fainting. Kegel exercises (tightening the muscles of the pelvic floor) work to improve urinary and rectal continence and are beneficial to both men and women. The exercises take time to work—it may be 4–8 weeks before you feel the effects.
The usual way of identifying the relevant muscles to focus on is to start urinating, then stop mid-stream. The tightening you feel when doing this are the muscles of the pelvic floor. When you restart the flow of urine, you release these pelvic floor muscles. Once identified, you can practice contracting and releasing these muscles independently of urination. One technique to practice is to contract the muscles of your pelvic floor slowly and hold for five seconds, then slowly release. Do this 25 times a day and you will notice a difference.