Patient information: Benign prostatic hyperplasia (BPH)

BPH OVERVIEW

Benign prostatic hyperplasia is a condition that occurs when the prostate enlarges, potentially slowing or blocking the urine stream. Other names for benign prostatic hyperplasia include benign prostatic hypertrophy, an enlarged prostate, and BPH. BPH occurs only in men; approximately 8 percent of men aged 31 to 40 have BPH. This increases to 40 to 50 percent of men by age 51 to 60, and to over 80 percent of men older than age 80.

The symptoms caused by BPH include frequent daytime and nighttime urination, a hesitant, interrupted, or weak stream of urine, and leaking or dribbling of urine. These symptoms are called lower urinary tract symptoms (LUTS). Many men with BPH have no symptoms; even among men with symptoms, the degree to which a man is bothered by his symptoms varies. For men with bothersome symptoms, treatment with one or more medications or surgery is available and is generally effective.

THE PROSTATE GLAND

The prostate is a small gland that is part of the male reproductive system. It sits just below the bladder and in front of the rectum (figure 1). The prostate is normally about the size of a walnut and weighs about 20 grams.

The prostate is composed of two lobes, covered by an outer layer of tissue. The prostate surrounds the urethra, the tube that carries urine from the bladder through the penis and outside the body. One role of the prostate gland is to secrete a fluid that helps to protect sperm from acid in the male urethra and the female vagina.

BENIGN PROSTATIC HYPERPLASIA CAUSES

It is not clear why some men develop symptoms of BPH or lower urinary tract symptoms (LUTS) and others do not. The prostate normally enlarges to some degree in all men with advancing age, although not all men require treatment. Several hormones, including testosterone, dihydrotestosterone, and estrogen, are required for BPH to develop, but these hormones alone do not cause the condition.

Some experts believe that a family history of the condition increases a man's risk of developing BPH. Sexual activity and having a vasectomy do not increase a man's chances of developing BPH.

BENIGN PROSTATIC HYPERPLASIA SYMPTOMS

The symptoms of BPH usually begin after age 50. The most common symptoms of BPH include:

• Frequent urination, especially at night
• A hesitant, interrupted, or weak stream of urine
• The need to urinate frequently
• Leaking or dribbling of urine

These symptoms tend to appear over time and may gradually worsen over the years. However, some men have an enlarged prostate that causes few or no symptoms while other men have symptoms of BPH that later improve or do not worsen. Some men are not bothered by their symptoms while others are bothered a great deal.

In a small percentage of men, untreated BPH can cause urinary retention, meaning that the man is unable to empty the bladder. Risks of urinary retention include recurrent urinary tract infections, a bodywide infection that begins in the bladder (called urosepsis), long-term damage to the kidneys (chronic kidney disease), or even kidney failure. The risk of urinary retention increases as age, symptoms, and prostate size increase.

Symptoms similar to those of BPH can also be caused by other conditions, including prostate or bladder cancer, kidney stones, and overactive bladder. Overactive bladder causes a strong, frequent, uncomfortable need to urinate immediately.

BENIGN PROSTATIC HYPERPLASIA DIAGNOSIS

To determine if other problems could be the cause of symptoms, a healthcare provider usually performs a medical history, physical examination, and laboratory tests.

History and physical examination — A number of issues must be considered in the medical history, including the man's age, family history, and use of medications.

The clinician may ask the patient questions to determine the severity and frequency of urinary symptoms. The American Urologic Association has developed a questionnaire to determine a symptom score (table 1). Symptoms are classified as mild (total score 0 to 7), moderate (total score 8 to 19), or severe (total score 20 to 35).

The International Prostate Symptom Score (IPSS) uses the same questions and scale as the AUA symptom score and adds a quality of life question: "If you were to spend the rest of your life with your urinary condition the way it is now, how would you feel about that?". The questionnaire is available online at www.usrf.org/questionnaires/AUA_SymptomScore.html.

Rectal examination — A clinician will need to perform a rectal examination to feel the size and shape of the prostate gland. A rectal exam can help to determine if a prostate nodule or hardened area on the prostate is present, which could be signs of prostate cancer.

The examination is performed while the man is bending over or lying on his side with his knees to his chest. The clinician inserts a gloved, lubricated finger into the rectum to determine if the prostate is enlarged or if the shape is abnormal. The only part of the prostate that is felt during the exam is the part nearest the rectum (figure 2).

Laboratory studies and diagnostic tests

Urinalysis — A urine sample may be requested to confirm that a man's symptoms are caused by BPH, rather than another problem such as a bladder infection. Signs of a bladder infection include the presence of blood or white blood cells in the urine. (See "Patient information: Bladder infections in adolescents and adults".)

Blood tests

• Prostate Specific Antigen Test — A blood test to check the prostate specific antigen (PSA) level is recommended. PSA is a protein produced by prostate cells; the PSA level should not be increased in men with BPH. Men who have prostate cancer often have an elevated PSA level, although prostate cancer is also found in men who do not have an elevated PSA.

Having BPH does not increase a man's risk for prostate cancer. However, it is possible for a man to have both BPH and prostate cancer at the same time. If a man's PSA test is elevated, further testing may be recommended to ensure that prostate cancer is not present. (See "Patient information: Prostate cancer diagnosis and staging".)

• Creatinine — Testing the blood level of creatinine is often recommended for men with signs of BPH. This test measures kidney function. Creatinine levels may be elevated in men as a result of an enlarged prostate that blocks urine flow or from kidney disease.

Urodynamic study — A urodynamic study may be recommended for some men who have signs or symptoms of BPH. Urodynamic testing is performed by measuring the rate and pattern of urine flow. In men with symptoms of BPH, urine flow is often slow and interrupted, and an increased amount of urine may be left in the bladder after urinating. The amount of urine left in the bladder after urination can be measured using an office ultrasound test called a bladder scan.

BENIGN PROSTATIC HYPERPLASIA TREATMENT

Treatments for BPH are intended to reduce urinary symptoms and improve urine flow rates. Treatment options include medications and surgery.

Men with mild BPH may not require treatment. In this case, most clinicians recommend a "wait and watch" approach, meaning that symptoms are monitored over time to determine if there is worsening. In some cases, BPH symptoms improve without treatment. However, men with moderate to severe symptoms usually require treatment.

Medications — There are two classes of medications that are often used to treat BPH: alpha-adrenergic antagonists and alpha-reductase inhibitors.

Alpha-adrenergic antagonists — These medications relax the smooth muscle of the prostate and bladder neck, which allows urine to flow more easily. There are at least four medications in this category: terazosin (Hytrin®), doxazosin (Cardura®), tamsulosin (Flomax®), and alfuzosin (Uroxatral®). Terazosin and doxazosin were initially developed to treat high blood pressure, but were later found to be useful for men with BPH.

Alpha-adrenergic antagonists begin to work quickly and are usually recommended as a first-line treatment for men with mild to moderate symptoms.

• Side effects — The most important side effects of alpha-adrenergic antagonists are low blood pressure after sitting or standing up and dizziness. Terazosin and doxazosin are usually taken at bedtime (to reduce lightheadedness). The dose can be increased over time if needed.

The effect of terazosin and doxazosin on blood pressure can be made worse if taken with a medication for erectile dysfunction (ED), such as sildenafil (Viagra®), vardenafil (Levitra®), and tadalafil (Cialis®). These medications should not be used by men who take terazosin or doxazosin. Tamsulosin and alfuzosin do not usually interact with ED medications.

Alpha-reductase inhibitors — 5-alpha-reductase inhibitors inhibit the production of dihydrotestosterone (DHT) from testosterone; DHT is a hormone involved in prostate enlargement. The medication may stop the prostate from growing further or, in some cases, cause it to shrink. The two medications in this category are finasteride (Proscar®) and dutasteride (Avodart®).

The 5-alpha-reductase inhibitors are more effective in men with larger prostates. The benefits of 5-alpha-reductase inhibitors, including reduced risks of urinary retention (inability to empty the bladder completely) and need for surgery, are generally seen within six months of treatment.

For men with severe symptoms, those with a large prostate (>40 g), and those who do not get an adequate response with the highest dose of an alpha-adrenergic antagonist, a combination treatment with an alpha-adrenergic antagonist and a 5-alpha-reductase inhibitor is often recommended.

• Side effects — A small percentage of men who take alpha-reductase inhibitors have decreased sex drive or ejaculatory or erectile dysfunction. This occurred in 4 to 6 percent of men in one study of finasteride [1]. Rarely, this problem causes men to stop BPH treatment. This side effect is reversed when the drug is stopped.

Levels of prostate-specific antigen (PSA) decrease by about 50 percent in men who take finasteride or dutasteride. This is important to consider when interpreting the results of a prostate specific antigen (PSA) test, used to screen for prostate cancer. (See "Patient information: Prostate cancer screening".)

Herbal medications — Herbal therapies for BPH, such as saw palmetto, are commonly used in Europe for treatment of BPH. However, the best trials of saw palmetto have shown no benefit in reducing the symptoms of BPH. For this reason, we do not recommend the use of saw palmetto or other herbal medications for the treatment of BPH.

Behavioral treatments — All men with BPH should avoid medications that can worsen symptoms or cause urinary retention. These include sedating antihistamines (eg, diphenhydramine [Benadryl®]) and decongestants (eg, pseudoephedrine [Sudafed®]).

Behavior changes may be helpful for men with bothersome urinary frequency. Suggested behavior changes include avoiding fluids prior to bedtime or before going out, consuming a reduced amount of fluids that worsen urinary frequency (eg, caffeine and alcohol), and double voiding. To double void, a man should empty his bladder, wait a few moments, and try to void again. Straining or pushing to empty is not recommended.

Surgical treatments — If drug therapy is not effective in relieving the symptoms of BPH, a surgical treatment may be recommended. Surgery is used to reduce to reduce the amount of prostate tissue around the urethra (figure 1). This may be done by removing prostate tissue or by shrinking the tissue with heat. Each treatment has advantages and disadvantages, and the best surgical treatment depends upon the size and location of the excess prostate tissue.

Transurethral resection of the prostate (TURP) — Transurethral resection of the prostate (TURP) is the most common surgical procedure for treating BPH. The surgery is done while a man is under anesthesia. A physician inserts a device through the patient's urethra to remove strips of the enlarged prostate. The procedure takes 60 to 90 minutes and generally requires a 24 hour observation period in the hospital.

In one study, about 9 percent of men who underwent TURP had a procedure-related complication, including a need for a catheter to empty the bladder temporarily (4 percent), injury of the prostate (2 percent), severe bleeding requiring transfusion (1 percent), urinary tract infection (1 percent) and a blood clot (0.4 percent) [2].

In this study, sexual function was similar in men who had TURP or watchful waiting [3]. Most men have a lower volume of semen with ejaculation after TURP because most of the semen is directed into the bladder. However, erectile function and pain with ejaculation may be improved after surgery.

Transurethral needle ablation (TUNA) — In this procedure, low-level radiofrequency energy is used to burn away specific areas of the enlarged prostate. This procedure improves urinary flow and helps BPH symptoms. TUNA can usually be performed using only local anesthesia (usually lidocaine gel, which is inserted into the urethra), and the man is usually able to go home after the procedure.

In one study that compared TUNA to TURP, men who underwent TUNA had fewer problems after the procedure, including reduced semen volume (0 versus 41 percent), erectile dysfunction (3 versus 21 percent), urinary incontinence (3 versus 21 percent), and narrowing of the urethra (2 versus 7 percent) [3]. However, more men treated with TUNA required retreatment for an enlarged prostate within five years compared to men who had TURP (14 versus 2 percent).

TUNA is often preferred for men with significant underlying medical problems, particularly men who must take blood-thinning medications such as warfarin (Coumadin®).

Other procedures — A number of other surgical procedures are available for men with BPH, including microwave thermotherapy, transurethral incision of the prostate (TIP), surgical removal of the prostate (called open prostatectomy), and laser treatment.

• Microwave thermotherapy — This procedure uses microwave heat to destroy excess prostate tissue. Microwave thermotherapy can be delivered through the urethra or through the rectum (figure 1). The procedure is performed in a day surgery treatment using local anesthesia (usually lidocaine gel, which is inserted into the urethra) and a pain medication taken by mouth. The man is usually able to go home after the procedure.

Thermotherapy does not cure BPH nor does it treat urinary retention. However, it does improve urinary urgency, the need to strain, urinary hesitancy and intermittent urine flow, and it can reduce urinary frequency.

• Transurethral incision of the prostate (TIP) — In this procedure, a surgeon widens the urethra by making a few incisions in the bladder neck and in the prostate gland (figure 1). Prostate tissue is not removed. TIP is performed with local, general, or epidural anesthesia, and generally requires a 24 hour observation period in the hospital.

Transurethral incision of the prostate (TIP) may be recommended for men who cannot empty their bladder but have relatively mild prostate enlargement, especially those with underlying medical problems. Retreatment for BPH with another surgical procedure is sometimes needed a few years after TIP.

• Open Prostatectomy — During open prostatectomy, a surgeon removes the enlarged portion of the prostate through an incision in the skin (figure 1). Open prostatectomy may be recommended for men with a very enlarged prostate.
• Laser Surgery — With laser surgery, a physician inserts a laser fiber through the patient's urethra and into the prostate (figure 1). Laser energy is used to destroy prostate tissue and cause the prostate to shrink. Laser surgery is similar to a TURP but it is associated with less bleeding. This procedure is gaining popularity as a possible alternative to a TURP.

WHERE TO GET MORE INFORMATION

Your healthcare provider is the best source of information for questions and concerns related to your medical problem. Because no two people are exactly alike and recommendations can vary from one person to another, it is important to seek guidance from a provider who is familiar with your individual situation.

This discussion will be updated as needed every four months on our web site (www.uptodate.com/patients). Additional topics as well as selected discussions written for healthcare professionals are also available for those who would like more detailed information.

Some of the most pertinent include:

Patient Level Information:
Patient information: Bladder infections in adolescents and adults
Patient information: Prostate cancer diagnosis and staging
Patient information: Prostate cancer screening

Professional Level Information:
Clinical manifestations and diagnosis of benign prostatic hyperplasia
Clinical use of saw palmetto
Epidemiology and pathogenesis of benign prostatic hyperplasia
Medical treatment of benign prostatic hyperplasia
Surgical and other invasive therapies of benign prostatic hyperplasia

A number of web sites have information about medical problems and treatments, although it can be difficult to know which sites are reputable. Information provided by the National Institutes of Health, national medical societies and some other well-established organizations are often reliable sources of information, although the frequency with which they are updated is variable.

• National Library of Medicine

      (www.nlm.nih.gov/medlineplus/prostatediseases.html)

• American Urological Association

      (www.urologyhealth.org/adult/index.cfm?cat=09)

• National Institute of Diabetes and Digestive and Kidney Diseases

      (http://kidney.niddk.nih.gov/kudiseases/pubs/prostateenlargement/index.htm)

• National Library of Medicine

     (www.nlm.nih.gov/medlineplus/prostatediseases.html)

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