American Medical Association Family Medical Guide - American Medical Association [555]
By age 50, more than half of all American men have signs of prostate enlargement. Although doctors are not sure what causes BPH, they know that it is linked to the male sex hormone testosterone and aging. (BPH does not occur in men whose testicles were surgically removed before puberty or in men whose testicles cannot produce testosterone.)
A diet high in fat and cholesterol may be a risk factor for BPH. Obesity is also a risk factor—men who have a waist size larger than 43 inches are twice as likely to develop BPH than are men who have a waist size of 35 inches or smaller. The risk increases with age.
Symptoms
The symptoms of BPH can result from either irritation or obstruction in the urinary tract. Symptoms of irritation are related to the bladder muscle and include a frequent need to urinate, numerous trips to the bathroom at night, and urgency (a strong urge to urinate). These symptoms are usually the first signs of a prostate problem, although they are often not noticeable until years after the prostate has begun to enlarge; they can also be a sign of other urinary tract disorders.
Enlarged prostate gland
An enlarged prostate can obstruct the urethra (the tube that carries urine from the bladder out of the body), reducing the flow of urine and causing the muscular wall of the bladder to thicken as it works harder to force urine out of the body.
Bladder outlet obstruction is a group of symptoms associated with BPH and related to problems with urine flow. These symptoms include decreased force and diameter of the urinary stream, inability to urinate, trouble starting the flow of urine, a weak flow of urine, double voiding (a person urinates and is able to urinate again in 5 to 10 minutes), dribbling after urination, and overflow urinary incontinence (leaking of urine from an overfull bladder). Frequent urinary tract infections, characterized by a burning sensation during urination, strong-smelling urine, and some blood in the urine, may also result from BPH. Bladder outlet obstruction tends to come and go.
Diagnosis
To diagnose BPH, a doctor takes a health history and performs a physical examination, including a urinalysis, to rule out infection. He or she may try to feel the bladder (which normally cannot be felt) by pressing down on the abdomen above the pelvic bone. The doctor also performs a digital rectal examination (by inserting a gloved, lubricated finger in the rectum) to feel the prostate and determine if and how much it is enlarged. He or she may recommend a test that uses a device called a uroflometer that measures the rate at which urine flows, to determine if the flow of urine from the bladder is obstructed. He or she may also perform an ultrasonic postvoid residual (PVR) urine test, a noninvasive test that measures the amount of urine left in the bladder after urination.
Blood tests may be recommended to rule out kidney disease or to screen for prostate cancer (see page 835). A procedure called cystoscopy (examination of the urinary tract with a viewing tube) may be done to evaluate the urinary tract and determine the extent of obstruction.
Treatment
BPH is a normal effect of aging, and therefore cannot be cured. However, the symptoms can be relieved with medication or surgery. If your symptoms are mild, your doctor may recommend a period of watchful waiting. During this time, he or she will carefully monitor your symptoms and try to determine whether external factors—such as consumption of alcohol or caffeine, exercise, or stress—are triggering your symptoms. The doctor will also perform tests regularly to check for signs of damage to your kidneys or bladder.
If your symptoms begin to worsen, your doctor