Benign Prostatic Hyperplasia
Benign prostatic hyperplasia (BPH) is a noncancerous enlargement of the prostate gland. As the prostate becomes larger, it can compress the urethra and obstruct the ﬂow and release of urine. It is difﬁcult to start urinating, and the stream of urine is weak. With such blockage, the bladder muscles enlarge and the bladder nerves become irritable, causing contractions of the bladder that result in a frequent urge to urinate. Eventually the muscles can no longer push urine past the blockage and urine backs up, leading to bladder problems, frequent urinary tract infections, and possible urinary retention (the inability to empty the blad- der). Urinary retention requires immediate treatment. BPH usually does not affect sexual function.
By age 50, more than half of all American men show some signs of prostate enlargement, and by age 70, more than 40 percent have enlargement that can be felt on physical examination. No one is sure what causes BPH, but researchers know that it requires the presence of testosterone. BPH does not occur in men who have had their testicles surgically removed or in men who are unable to metabolize testosterone.
Recent studies point to a high-fat and high-cholesterol diet as a risk factor for BPH. Obesity also may be a risk factor. Men with a waist size of more than 43 inches are twice as likely to develop BPH as are men with a waist size of 35 inches or smaller. However, there is no conclusive evidence of a link between obesity and BPH.
Symptoms of BPH are generally described as irritative or obstructive. Irrita- tive symptoms, which are related to bladder muscle failure, include the frequent need to urinate, numerous trips to the bathroom at night, and urgency (the fre- quent or constant urge to urinate). These are generally the ﬁrst signs of a prostate problem, even though they might not be noticeable until years after the prostate has begun to enlarge.
Bladder outlet obstruction is a term used to describe a cluster of obstructive symptoms associated with BPH and related to problems with urine ﬂow. They
include decreased force and diameter of the urinary stream, the inability to uri- nate, trouble starting the ﬂow of urine, a weak ﬂow, double voiding (after uri- nating, a man is able to urinate again in 5 to 10 minutes), dribbling after urination, and overﬂow urinary incontinence. Other symptoms associated with BPH may include frequent urinary infections marked by a burning feeling dur- ing urination and strong-smelling urine. There may also be some blood in the urine, which occurs when blood vessels are stretched and broken by enlarging prostate tissue.
Men who have these symptoms should see their doctor. Other diseases, includ- ing cancer, can cause these symptoms. Although BPH is not cancerous, advanced stages can lead to complications related to kidney damage or kidney failure.
To diagnose BPH, a doctor takes a medical history and performs a physical examination, including a urinalysis, to rule out infection. The doctor examines the bladder by pressing down on the abdomen. He or she will perform a digital rectal examination by inserting a gloved, lubricated ﬁnger into the rectum to feel the prostate and determine whether it is enlarged.
Since the part of the prostate that usually obstructs urine ﬂow is the tissue immediately surrounding the urethra, which cannot be felt during a rectal examination, a digital rectal examination is somewhat limited in diagnosing obstruction due to BPH. Therefore, the doctor may perform a test known as a urodynamic evaluation to measure urine ﬂow. The amount of urine left in the bladder after urination also will be measured.
Blood tests may be done to rule out kidney dysfunction or to screen for prostate cancer. Ultrasound tests may be used to create an image of the prostate. Cystoscopy (examination with a viewing tube) also may be done to allow visual examination of the urinary tract. While none of these tests alone can diagnose BPH with certainty, as a group they can support a diagnosis.
BPH cannot be cured, but its symptoms can be relieved by various medica- tions and surgical techniques. Initially, before symptoms become overly bother- some, a physician may suggest a “watchful waiting” approach that does not include any treatment. This involves asking the patient to keep track of symp- toms to see if they lessen or stabilize on their own, or whether there are certain external factors that bring on the symptoms, such as intake of caffeine or alco- hol, exercise, or stress.
As the problems associated with bladder outlet obstruction due to BPH become less tolerable or intolerable, more aggressive treatments may be used. There are two types of medication used to treat an enlarged prostate: alpha- blockers (which are medications to reduce high blood pressure) and drugs that shrink the prostate. Because symptoms return if medication is stopped, medica- tion must be taken indeﬁnitely.
Alpha-blockers work in about 75 percent of men who try them. These med- ications, such as terazosin, work by relaxing the muscular component of the
prostate, which often allows urine to ﬂow more freely. The problem with alpha- blockers is their side effects, which initially include low blood pressure and dizziness on standing. These symptoms typically lessen or disappear with con- tinued use of the drugs. A newer alpha-blocker used to treat BPH, called tamsu- losin, may be less likely to cause these side effects.
Finasteride is a drug that relieves symptoms by reducing the size of the prostate. Finasteride takes about 3 to 6 months before it starts to work, but it has been shown to reduce the size of the prostate by 30 percent. Up to 60 percent of men who use ﬁnasteride reported some relief of their symptoms. However, the relief comes with some serious possible side effects. In some cases, ﬁnasteride has been associated with a decreased sex drive and erection problems. There is also evidence that ﬁnasteride reduces the level of PSA (prostate-speciﬁc anti- gen; see page 174) in the bloodstream by approximately half. For this reason, doctors take this into account when measuring PSA levels for detecting prostate cancer in men who are taking ﬁnasteride.
A variety of surgical procedures are used to treat BPH by removing or reduc- ing prostate tissue. A prostatectomy is the removal of part of the prostate gland. A prostatectomy can be either open or closed. In an open prostatectomy, the gland or excess tissue that is causing the obstruction is removed through an abdominal incision. In a closed prostatectomy, surgery is done through a cys- toscope (viewing tube) that is inserted up the urethra. Although closed prosta- tectomies have largely replaced open prostatectomies, open procedures are still performed if the prostate gland is very large or if other procedures are per- formed at the same time.
Transurethral resection of the prostate (TURP) is a closed procedure. TURP involves passing a special cystoscope called a resectoscope into the urethra and inserting a tiny wire loop or cutting edge up through the scope to remove excess prostate tissue from around the urethra. TURP is one of the most commonly per- formed surgical procedures, with 300,000 to 400,000 done each year. One major beneﬁt of this procedure is reduction of urinary problems associated with BPH. Approximately 90 percent of men who undergo this procedure show improve- ment in their urinary symptoms. However, approximately 1 percent of men who have this procedure experience subsequent problems with urinary incontinence. The procedure may need to be repeated if the tissue that was removed grows back.
Another closed procedure is known as transurethral incision of the prostate (TUIP). This procedure differs from TURP in that the surgeon makes tiny cuts in the prostate to lessen its grip on the urethra. TUIP reduces the chances of expe- riencing certain problems after surgery, such as retrograde ejaculation, which is ejaculation backward into the bladder during sexual intercourse. In some cases, repeated procedures may be necessary.
Other treatments for benign prostatic hyperplasia are currently being devel-oped. Among them are microwave thermotherapy, intraurethral stents, laser ther- apy, and transurethral needle ablation (TUNA). Microwave thermotherapy uses heat generated by microwaves to eliminate excess prostate tissue. Intraurethral stents are small, tubelike structures that are inserted into the urethra to enlarge it and provide relief from urinary symptoms. Laser therapy uses laser energy to vaporize excess prostate tissue. TUNA uses microwave technology to cut away obstructing tissue. The long-term effectiveness of these techniques has not yet been determined. No matter which treatment you are considering, be sure to dis- cuss the risks and the beneﬁts with your doctor so that you can make an informed decision.
A man with an enlarged prostate may ﬁnd that certain foods and medications may increase the intensity of BPH symptoms. Try the following lifestyle changes and keep track of your symptoms:
• Stick to a low-fat, low-cholesterol diet. Men who follow such a diet have a lower risk of BPH.
• Eat more vegetables. Men who do so have a lower rate of BPH than those who do not.
• Limit your ﬂuid intake, particularly at bedtime. It may help reduce the number of times you have to get up to urinate in the middle of the night.
• Avoid caffeine and alcohol. They may irritate the prostate and increase the need for nighttime urination.
• Monitor your medications. Certain drugs—including oral bronchodilators, diuretics, tranquilizers, and antidepressants, as well as over-the-counter reme- dies such as antihistamines and decongestants—aggravate urinary problems. Check with your pharmacist.